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Search for "viscosity" in Full Text gives 106 result(s) in Beilstein Journal of Organic Chemistry.
Application of olefin metathesis in the synthesis of functionalized polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials
- Patrycja Żak and
- Cezary Pietraszuk
Beilstein J. Org. Chem. 2019, 15, 310–332, doi:10.3762/bjoc.15.28
- can significantly improve such properties of the polymer as thermal and oxidative resistance, surface properties, improvement of mechanical properties as well as reduced flammability, heat release and viscosity during processing [29]. Synthesis, properties and applications of POSS-containing materials
Graphical Abstract
Figure 1: Cubic octasilsesquioxane.
Scheme 1: Reactivity of vinylsilanes in the presence of ruthenium alkylidene complexes; a) cross metathesis, ...
Figure 2: The scope and limitations of metathesis in transformations of vinyl-substituted siloxanes and silse...
Scheme 2: Application of olefin metathesis in the synthesis and modification of POSS-based materials: a) func...
Figure 3: Olefin metathesis catalysts used in transformations of silsesquioxanes.
Figure 4: Octavinyl-substituted cubic silsesquioxane (OVS) and spherosilicate.
Scheme 3: Cross metathesis of OVS with terminal olefins (stereoselectivity as discussed in the text).
Scheme 4: Cross metathesis of OVS with substituted styrenes.
Scheme 5: Modification of OVS via CM with styrenes.
Figure 5: Vinylbiphenyl chromophore-decorated cubic silsesquioxanes.
Scheme 6: Cross metathesis of OVS with carboranylstyrene.
Scheme 7: Synthesis of octakis[2-(p-carboxyphenyl)ethyl]silsesquioxane via CM and subsequent hydrogenation.
Scheme 8: Cross metathesis of monovinyl-POSS with olefins.
Scheme 9: Cross metathesis of monovinyl-POSS with highly π-conjugated substituted styrenes.
Scheme 10: Cross metathesis of monovinylgermasilsesquioxane with styrenes.
Scheme 11: Cross metathesis of DDSQ-2SiVi with olefins.
Scheme 12: Cross metathesis of DDSQ-2SiVi with substituted styrenes.
Scheme 13: Cross metathesis of (DDSQ-2GeVi) with olefins.
Scheme 14: CM of divinyl-substituted T10 and T12 with 4-bromostyrene (selected isomers are shown).
Scheme 15: Synthesis of vinylstilbene derivatives of T10 and T12 via a sequence of CM and Heck coupling.
Scheme 16: Cross metathesis of allyl-POSS with tert-butyl acrylate and (Z)-1,4-diacetoxy-but-2-ene.
Scheme 17: Cross metathesis of allyl-POSS with olefins.
Scheme 18: Acyclic diene metathesis copolymerization of DDSQ-2SiVi with diolefins.
Scheme 19: Acyclic diene metathesis copolymerization of DDSQ-2GeVi with diolefins.
Scheme 20: Ring-opening metathesis copolymerization of norbornenylethyl-POSS with norbornene.
Scheme 21: Synthesis of a polyethylene–POSS copolymer via ring-opening metathesis copolymerization of norborne...
Scheme 22: ROMP of norbornenylethyl-POSS with 1,5-cyclooctadiene.
Scheme 23: Copolymerization of POSS-functionalized norbornene with DCPD.
Scheme 24: Copolymerization of tris(norbornenylethyl)-POSS with DCPD.
Scheme 25: Copolymerization of N-(propyl-POSS)-7-oxanorbornene-5,6-dicarboximide with 3-(trifluoromethyl)pheny...
Figure 6: Homopolymers and copolymers having POSS groups attached to the main chain via flexible spacers of d...
Scheme 26: Ring-opening metathesis copolymerization of POSS-NBE with methyltetracyclododecene.
Scheme 27: Synthesis of block copolymer via ROMP by sequential monomer addition.
Scheme 28: Synthesis of a liquid crystalline polymer with POSS core in the side chain.
Scheme 29: Sequential synthesis of copolymers of polynorbornene containing POSS and PEO pendant groups.
Scheme 30: Synthesis of rodlike POSS−bottlebrush block copolymers [54].
Scheme 31: Surface-initiated ROMP producing copolymer layers on the surface of CdSe/ZnS quantum dots.
Olefin metathesis in multiblock copolymer synthesis
- Maria L. Gringolts,
- Yulia I. Denisova,
- Eugene Sh. Finkelshtein and
- Yaroslav V. Kudryavtsev
Beilstein J. Org. Chem. 2019, 15, 218–235, doi:10.3762/bjoc.15.21
- by light scattering [90]. Another possible concern is related to the high viscosity of the initial polymer mixture, especially in the case of high molecular mass components, like PNB. Fortunately, upon the catalyst addition such mixtures rapidly become more fluid because of polymer-chain scission
Graphical Abstract
Scheme 1: Multiblock copolymer synthesis by sequential ROMP, replotted from [51].
Figure 1: The most known commercially available catalysts for olefin metathesis.
Scheme 2: Multiblock copolymer synthesis by combining ROMP and NMP, replotted from [56].
Figure 2: A highly fluorescent multiblock copolymer for bioimaging and in vivo tumor targeting [60].
Scheme 3: Multiblock copolymer synthesis by combining ROMP and click reactions replotted from [61].
Scheme 4: Multiblock copolymer synthesis by combining ADMET and other reactions, replotted from [63,64].
Scheme 5: Synthesis of multiblock bottle-brush copolymers by ROMP, replotted from [68].
Scheme 6: Sacrificial synthesis of multiblock copolymers, replotted from [70].
Scheme 7: Synthesis of supramolecular multiblock copolymers, replotted from [74].
Figure 3: The multiblock copolymer capable of post-functionalization [76].
Figure 4: Multiblock copolymers synthesized by macromolecular cross metathesis.
Scheme 8: Macromolecular cross metathesis.
Figure 5: Changes in the DSC thermograms during MCM of PBD and polyesters (left) [84] and PNB–PCOE (right) mediat...
Figure 6: The 13C NMR spectrum recorded after 8 h of the reaction between PCOE, PNB, and Gr1; the homo- and h...
Scheme 9: Elementary reactions of MCM between PNB and PCOE, replotted from [90].
Figure 7: The 1H NMR spectrum recorded after 24 h of the reaction between PCOE, PNB, and Gr1 in CDCl3. The ca...
Scheme 10: Post-modification of multiblock copolymers by hydrogenation (A) [85] and epoxidation (B) [101] of C=C double...
Figure 8: Integral distribution functions for the lamella thickness of crystallites in thermally fractionated...
Adhesion, forces and the stability of interfaces
- Robin Guttmann,
- Johannes Hoja,
- Christoph Lechner,
- Reinhard J. Maurer and
- Alexander F. Sax
Beilstein J. Org. Chem. 2019, 15, 106–129, doi:10.3762/bjoc.15.12
- , and for many properties such as boiling point or viscosity of liquids. Basics of Weak Molecular Interaction Description of interaction through forces and potentials Interactions in a system consisting of two or more subsystems cause changes of the spatial positions of the subsystems relative to each
Graphical Abstract
Figure 1: Left: The graphs of an interaction potential Vint composed of an attractive component Vatt and a re...
Figure 2: From left to right: An external pulling force acting on the system in its equilibrium structure inc...
Figure 3: Potential functions (thin lines) and the first derivatives (thick lines). Left: For constant ΔV the...
Figure 4: Left: The disk covering the atoms of molecule B seen by an atom in molecule A expands with increasi...
Figure 5: Demonstration of the contact zone and the reduced contact zone of an adsorbate/adsorbent complex wi...
Figure 6: The contact zone of an (8.0)-CNT/tetracene complex. The bold black lines in the traverse section re...
Figure 7: The separation of tetracene from graphene. Top row: Mode S1 (left), mode S2 (right). Bottom row: mo...
Figure 8: The slope functions for the separation of tetracene from graphene for the four separation modes. Re...
Figure 9: Boiling points of straight-chain primary alcohols, straight-chain primary amines and straight-chain...
Fabrication of supramolecular cyclodextrin–fullerene nonwovens by electrospinning
- Hiroaki Yoshida,
- Ken Kikuta and
- Toshiyuki Kida
Beilstein J. Org. Chem. 2019, 15, 89–95, doi:10.3762/bjoc.15.10
- realizes easy handling of inclusion complexation with guest molecules as well as electrospinning due to the much lower viscosity of the CD/HFIP solution. The formation of a 2:1 inclusion complex should not affect the solution properties (e.g., viscosity and solubility), but should provide electrospinning
- is essential. Association is predicted from the relationship of the solution viscosity and concentration [6][9][11]. As reported previously, the increased rate of viscosity with the concentration in γ-CD/HFIP solution clearly becomes larger at 10–15 w/v %, indicating intermolecular associations of γ
- -CD molecules in HFIP [11]. Interestingly, no significant viscosity differences are observed after C60 addition into γ-CD/HFIP solution (Figure S4 in Supporting Information File 1). This is important from the viewpoint that the solution properties are governed by the intermolecular interactions
Graphical Abstract
Figure 1: Schematic illustration of the fabrication of host–guest supramolecular fibers with molecularly disp...
Figure 2: Formation of a γ-CD–C60 inclusion complex in HFIP under sonication for 60 h. (a) UV–vis absorption ...
Figure 3: Fabrication of γ-CD–C60 inclusion complex nonwovens by electrospinning. Photographs and SEM images ...
Figure 4: Extended variation of CD–fullerene inclusion complex to fabricate supramolecular solid functional f...
Dynamic light scattering studies of the effects of salts on the diffusivity of cationic and anionic cavitands
- Anthony Wishard and
- Bruce C. Gibb
Beilstein J. Org. Chem. 2018, 14, 2212–2219, doi:10.3762/bjoc.14.195
- Boltzmann constant, T is the temperature, η is the viscosity of the solution, and rH is the hydrodynamic radius. In all cases, at the initial 20 mM concentration of NaOH the light scattering induced by 1 was weak. This resulted in relatively flat autocorrelation functions generated from the measured
Graphical Abstract
Figure 1: Chemical structures of octaacid 1 and positand 2 showing the anionic binding sites of the two hosts...
Figure 2: Representative plots of the volume-weighted distribution obtained by DLS for salts titrated into 2....
Figure 3: Representative plots of the volume-weighted distribution obtained by DLS for salts titrated into 2....
Scheme 1: Visualization of the competitive equilibrium between iodide binding to host 2 or associating with i...
An overview of recent advances in duplex DNA recognition by small molecules
- Sayantan Bhaduri,
- Nihar Ranjan and
- Dev P. Arya
Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93
- absorption spectroscopy, viscosity measurement, cyclic voltammetry and molecular modeling (Figure 9) [93]. Docking results confirmed that these complexes have the ability to interact with the minor groove of the ct-DNA. In addition, the authors confirmed that in presence of ascorbic acid, these complexes
Graphical Abstract
Figure 1: A figure showing the hydrogen bonding patterns observed in (a) duplex (b) triplex and (c) quadruple...
Figure 2: (a) Portions of MATα1–MATα2 are shown contacting the minor groove of the DNA substrate. Key arginin...
Figure 3: Chemical structures of naturally occurring and synthetic hybrid minor groove binders.
Figure 4: Synthetic structural analogs of distamycin A by replacing one or more pyrrole rings with other hete...
Figure 5: Pictorial representation of the binding model of pyrrole–imidazole (Py/Im) polyamides based on the ...
Figure 6: Chemical structures of synthetic “hairpin” pyrrole–imidazole (Py/Im) conjugates.
Figure 7: (a) Minor groove complex formation between DNA duplex and 8-ring cyclic Py/Im polyamide (conjugate ...
Figure 8: Telomere-targeting tandem hairpin Py/Im polyamides 23 and 24 capable of recognizing >10 base pairs; ...
Figure 9: Representative examples of recently developed DNA minor groove binders.
Figure 10: Chemical structures of bisbenzamidazoles Hoechst 33258 and 33342 and their synthetic structural ana...
Figure 11: Chemical structures of bisamidines such as diminazene, DAPI, pentamidine and their synthetic struct...
Figure 12: Representative examples of recently developed bisamidine derivatives.
Figure 13: Chemical structures of chromomycin, mithramycin and their synthetic structural analogs 91 and 92.
Figure 14: Chemical structures of well-known naturally occurring DNA binding intercalators.
Figure 15: Naturally occurring indolocarbazole rebeccamycin and its synthetic analogs.
Figure 16: Representative examples of naturally occurring and synthetic derivatives of DNA intercalating agent...
Figure 17: Several recent synthetic varieties of DNA intercalators.
Figure 18: Aminoglycoside (neomycin)–Hoechst 33258/intercalator conjugates.
Figure 19: Chemical structures of triazole linked neomycin dimers and neomycin–bisbenzimidazole conjugates.
Figure 20: Representative examples of naturally occurring and synthetic analogs of DNA binding alkylating agen...
Figure 21: Chemical structures of naturally occurring and synthetic analogs of pyrrolobenzodiazepines.
Mechanochemistry of nucleosides, nucleotides and related materials
- Olga Eguaogie,
- Joseph S. Vyle,
- Patrick F. Conlon,
- Manuela A. Gîlea and
- Yipei Liang
Beilstein J. Org. Chem. 2018, 14, 955–970, doi:10.3762/bjoc.14.81
- POCl3 (e.g., Scheme 10), monoalkyl phosphorodichloridates or dialkyl phosphoromonochloridates in the absence of solvent has been reported [48]. Migaud and co-workers prepared highly water-sensitive phosphitylating agents directly from PCl3 in low viscosity ionic liquids derived from the tris
Graphical Abstract
Figure 1: Examples of equipment used to perform mechanochemistry on nucleoside and nucleotide substrates (not...
Figure 2: Ganciclovir.
Scheme 1: Nucleoside tritylation effected by hand grinding in a heated mortar and pestle.
Scheme 2: Persilylation of ribonucleoside hydroxy groups (and in situ acylation of cytidine) in a MBM.
Scheme 3: Nucleoside amine and carboxylic acid Boc protection using an improvised attritor-type mill.
Scheme 4: Nucleobase Boc protection via transient silylation using an improvised attritor-type mill.
Scheme 5: Chemoselective N-acylation of an aminonucleoside using LAG in a MBM.
Scheme 6: Azide–alkyne cycloaddition reactions performed in a copper vessel in a MBM.
Figure 3: a) Custom-machined copper vessel and zirconia balls used to perform CuAAC reactions (showing: upper...
Scheme 7: Thiolate displacement reactions of nucleoside derivatives in a MBM.
Scheme 8: Selenocyanate displacement reactions of nucleoside derivatives in a MBM.
Scheme 9: Nucleobase glycosidation reactions and subsequent deacetylation performed in a MBM.
Scheme 10: Regioselective phosphorylation of nicotinamide riboside in a MBM.
Scheme 11: Preparation of nucleoside phosphoramidites in a MBM using ionic liquid-stabilised chlorophosphorami...
Scheme 12: Preparation of a nucleoside phosphite triester using LAG in a MBM.
Scheme 13: Internucleoside phosphate coupling linkages in a MBM.
Scheme 14: Preparation of ADPR analogues using in a MBM.
Scheme 15: Synthesis of pyrophosphorothiolate-linked dinucleoside cap analogues in a MBM to effect hydrolytic ...
Figure 4: Early low temperature mechanised ball mill as described by Mudd et al. – adapted from reference [78].
Scheme 16: Co-crystal grinding of alkylated nucleobases in an amalgam mill (N.B. no frequency was recorded in ...
Figure 5: Materials used to prepare a smectic phase.
Figure 6: Structures of 5-fluorouracil (5FU) and nucleoside analogue prodrugs subject to mechanochemical co-c...
Scheme 17: Preparation of DNA-SWNT complex in a MBM.
Liquid-assisted grinding and ion pairing regulates percentage conversion and diastereoselectivity of the Wittig reaction under mechanochemical conditions
- Kendra Leahy Denlinger,
- Lianna Ortiz-Trankina,
- Preston Carr,
- Kingsley Benson,
- Daniel C. Waddell and
- James Mack
Beilstein J. Org. Chem. 2018, 14, 688–696, doi:10.3762/bjoc.14.57
- formation of this bond may have a large influence under mechanochemical conditions because there is not a solvent reservoir to accept the dispersion of these ions. Using Pearson’s hard and soft acid and base (HSAB) theory [29] and the Jones–Dole viscosity B coefficient [30] (Table 3), we can predict which
- alkali metal and halide pairs would be most favourable. For example, bromide is a borderline soft anion, so based on the proposed mechanism we would expect more product to form if the counter ion is Cs+(soft) than if it was Li+ (hard). Using the Jones–Dole viscosity B coefficient, we could also predict
- higher E selectivity was obtained. The high concentration of reactants under mechanochemical conditions allows for unique and potentially selective reactions that may not be achievable by traditional synthetic means. Further studies on the influence of HSAB theory and the Jones–Dole viscosity B
Graphical Abstract
Figure 1: Solution-based Wittig reaction mechanism.
Figure 2: 1H NMR spectra of stilbene mixture (a) and benzyl benzoate (b).
Scheme 1: Possible mechanism of benzyl benzoate formation.
Scheme 2: A possible mechanistic explanation for the E selectivity.
Scheme 3: Ball-milled Wittig reaction using excess benzaldehyde.
Figure 3: Comparison of solution based Wittig reaction (a) with polymer-supported mechanochemical Wittig reac...
Scheme 4: Stepwise ball-milled Wittig reaction with ethanol as the LAG solvent.
Scheme 5: Stepwise ball-milled Wittig reaction with ethanol evaporation between the steps.
5-Aminopyrazole as precursor in design and synthesis of fused pyrazoloazines
- Ranjana Aggarwal and
- Suresh Kumar
Beilstein J. Org. Chem. 2018, 14, 203–242, doi:10.3762/bjoc.14.15
- techniques like electronic spectra, viscosity measurement and thermal denaturation. Ahmetaj et al. [105] described a simple and efficient protocol for the synthesis of 7-heteroarylpyrazolo[1,5-a]pyrimidine-3-carboxamides 166 from the reaction of 5-aminopyrazole 161 with (E)-3-(dimethylamino)-1-(heteroaryl
Graphical Abstract
Figure 1: Selected examples of drugs with fused pyrazole rings.
Figure 2: Typical structures of some fused pyrazoloazines from 5-aminopyrazoles.
Scheme 1: Regiospecific synthesis of 4 and 6-trifluoromethyl-1H-pyrazolo[3,4-b]pyridines.
Scheme 2: Synthesis of pyrazolo[3,4-b]pyridine-6-carboxylates.
Scheme 3: Synthesis of 1,4,6-triaryl-1H-pyrazolo[3,4-b]pyridines with ionic liquid .
Scheme 4: Synthesis of coumarin-based isomeric tetracyclic pyrazolo[3,4-b]pyridines.
Scheme 5: Synthesis of 6-substituted pyrazolo[3,4-b]pyridines under Heck conditions.
Scheme 6: Microwave-assisted palladium-catalyzed synthesis of pyrazolo[3,4-b]pyridines.
Scheme 7: Acid-catalyzed synthesis of pyrazolo[3,4-b]pyridines via enaminones.
Scheme 8: Synthesis of pyrazolo[3,4-b]pyridines via aza-Diels–Alder reaction.
Scheme 9: Synthesis of macrocyclane fused pyrazolo[3,4-b]pyridine derivatives.
Scheme 10: Three-component synthesis of 4,7-dihydro-1H-pyrazolo[3,4-b]pyridine derivatives.
Scheme 11: Ultrasonicated synthesis of spiro[indoline-3,4'-pyrazolo[3,4-b]pyridine]-2,6'(1'H)-diones.
Scheme 12: Synthesis of spiro[indoline-3,4'-pyrazolo[3,4-b]pyridine] derivatives under conventional heating co...
Scheme 13: Nanoparticle-catalyzed synthesis of pyrazolo[3,4-b]pyridine-spiroindolinones.
Scheme 14: Microwave-assisted multicomponent synthesis of spiropyrazolo[3,4-b]pyridines.
Scheme 15: Unexpected synthesis of naphthoic acid-substituted pyrazolo[3,4-b]pyridines.
Scheme 16: Multicomponent synthesis of variously substituted pyrazolo[3,4-b]pyridine derivatives.
Scheme 17: Three-component synthesis of 4,7-dihydropyrazolo[3,4-b]pyridines and pyrazolo[3,4-b]pyridines.
Scheme 18: Synthesis of pyrazolo[3,4-b]pyridine-5-spirocycloalkanediones.
Scheme 19: Ultrasound-mediated three-component synthesis of pyrazolo[3,4-b]pyridines.
Scheme 20: Multicomponent synthesis of 4-aryl-3-methyl-1-phenyl-4,6,8,9-tetrahydropyrazolo [3,4-b]thiopyrano[4...
Scheme 21: Synthesis of 2,3-dihydrochromeno[4,3-d]pyrazolo[3,4-b]pyridine-1,6-diones.
Scheme 22: FeCl3-catalyzed synthesis of o-hydroxyphenylpyrazolo[3,4-b]pyridine derivatives.
Scheme 23: Ionic liquid-mediated synthesis of pyrazolo[3,4-b]pyridines.
Scheme 24: Microwave-assisted synthesis of pyrazolo[3,4-b]pyridines.
Scheme 25: Multicomponent synthesis of pyrazolo[3,4-b]pyridine-5-carbonitriles.
Scheme 26: Unusual domino synthesis of 4,7-dihydropyrazolo[3,4-b]pyridine-5-nitriles.
Scheme 27: Synthesis of 4,5,6,7-tetrahydro-4H-pyrazolo[3,4-b]pyridines under conventional heating and ultrasou...
Scheme 28: L-Proline-catalyzed synthesis of of pyrazolo[3,4-b]pyridine.
Scheme 29: Microwave-assisted synthesis of 5-aminoarylpyrazolo[3,4-b]pyridines.
Scheme 30: Microwave-assisted multi-component synthesis of pyrazolo[3,4-e]indolizines.
Scheme 31: Synthesis of fluoropropynyl and fluoroalkyl substituted pyrazolo[1,5-a]pyrimidine.
Scheme 32: Acid-catalyzed synthesis of pyrazolo[1,5-a]pyrimidine derivatives.
Scheme 33: Chemoselective and regiospecific synthesis of 2-(3-methylpyrazol-1’-yl)-5-methylpyrazolo[1,5-a]pyri...
Scheme 34: Regioselective synthesis of 7-trifluoromethylpyrazolo[1,5-a]pyrimidines.
Scheme 35: Microwave-assisted synthesis of 7-trifluoromethylpyrazolo[1,5-a]pyrimidine carboxylates.
Scheme 36: Microwave and ultrasound-assisted synthesis of 7-trifluoromethylpyrazolo[1,5-a]pyrimidines.
Scheme 37: Base-catalyzed unprecedented synthesis of pyrazolo[1,5-a]pyrimidines via C–C bond cleavage.
Scheme 38: Synthesis of aminobenzothiazole/piperazine linked pyrazolo[1,5-a]pyrimidines.
Scheme 39: Synthesis of aminoalkylpyrazolo[1,5-a]pyrimidine-7-amines.
Scheme 40: Synthesis of pyrazolo[1,5-a]pyrimidines from condensation of 5-aminopyrazole 126 and ethyl acetoace...
Scheme 41: Synthesis of 7-aminopyrazolo[1,5-a]pyrimidines.
Scheme 42: Unexpected synthesis of 7-aminopyrazolo[1,5-a]pyrimidines under solvent free and solvent-mediated c...
Scheme 43: Synthesis of N-(4-aminophenyl)-7-aryloxypyrazolo[1,5-a]pyrimidin-5-amines.
Scheme 44: Base-catalyzed synthesis of 5,7-diarylpyrazolo[1,5-a]pyrimidines.
Scheme 45: Synthesis of 6,7-dihydropyrazolo[1,5-a]pyrimidines in PEG-400.
Scheme 46: Synthesis of 7-heteroarylpyrazolo[1,5-a]pyrimidine-3-carboxamides.
Scheme 47: Synthesis of 7-heteroarylpyrazolo[1,5-a]pyrimidine derivatives under conventional heating and micro...
Scheme 48: Synthesis of N-aroylpyrazolo[1,5-a]pyrimidine-5-amines.
Scheme 49: Regioselective synthesis of ethyl pyrazolo[1,5-a]pyrimidine-7-carboxylate.
Scheme 50: Sodium methoxide-catalyzed synthesis of 3-cyano-6,7-diarylpyrazolo[1,5-a]pyrimidines.
Scheme 51: Synthesis of various pyrazolo[3,4-d]pyrimidine derivatives.
Scheme 52: Synthesis of hydrazinopyrazolo[3,4-d]pyrimidine derivatives.
Scheme 53: Synthesis of N-arylidinepyrazolo[3,4-d]pyrimidin-5-amines.
Scheme 54: Synthesis of pyrazolo[3,4-d]pyrimidinyl-4-amines.
Scheme 55: Iodine-catalyzed synthesis of pyrazolo[3,4-d]pyrimidinones.
Scheme 56: Synthesis of ethyl 6-amino-2H-pyrazolo[3,4-d]pyrimidine-4-carboxylate.
Scheme 57: Synthesis of 4-substituted-(3,6-dihydropyran-4-yl)-1H-pyrazolo[3,4-d]pyrimidines.
Scheme 58: Synthesis of 1-(2,4-dichlorophenyl)pyrazolo[3,4-d]pyrimidin-4-yl carboxamides.
Scheme 59: Synthesis of 5-(1,3,4-thidiazol-2-yl)pyrazolo[3,4-d]pyrimidine.
Scheme 60: One pot POCl3-catalyzed synthesis of 1-arylpyrazolo[3,4-d]pyrimidin-4-ones.
Scheme 61: Synthesis of 4-amino-N1,C3-dialkylpyrazolo[3,4-d]pyrimidines under Suzuki conditions.
Scheme 62: Microwave-assisted synthesis of pyrazolo[3,4-b]pyrazines.
Scheme 63: Synthesis and derivatization of pyrazolo[3,4-b]pyrazine-5-carbonitriles.
Scheme 64: Synthesis of 2-thioxo-pyrazolo[1,5-a][1,3,5]triazin-4-ones.
Scheme 65: Synthesis of 2,3-dihydropyrazolo[1,5-a][1,3,5]triazin-4(1H)-one.
Scheme 66: Synthesis of pyrazolo[1,5-a][1,3,5]triazine-8-carboxylic acid ethyl ester.
Scheme 67: Microwave-assisted synthesis of 4,7-dihetarylpyrazolo[1,5-a][1,3,5]triazines.
Scheme 68: Alternative synthetic route to 4,7-diheteroarylpyrazolo[1,5-a][1,3,5]triazines.
Scheme 69: Synthesis of 4-aryl-2-ethylthio-7-methylpyrazolo[1,5-a][1,3,5]triazines.
Scheme 70: Microwave-assisted synthesis of 4-aminopyrazolo[1,5-a][1,3,5]triazine.
Scheme 71: Synthesis of pyrazolo[3,4-d][1,2,3]triazines from pyrazol-5-yl diazonium salts.
Scheme 72: Synthesis of 2,5-dihydropyrazolo[3,4-e][1,2,4]triazines.
Scheme 73: Synthesis of pyrazolo[5,1-c][1,2,4]triazines via diazopyrazolylenaminones.
Scheme 74: Synthesis of pyrazolo[5,1-c][1,2,4]triazines in presence of sodium acetate.
Scheme 75: Synthesis of various 7-diazopyrazolo[5,1-c][1,2,4]triazine derivatives.
Scheme 76: One pot synthesis of pyrazolo[5,1-c][1,2,4]triazines.
Scheme 77: Synthesis of 4-amino-3,7,8-trinitropyrazolo-[5,1-c][1,2,4]triazines.
Scheme 78: Synthesis of tricyclic pyrazolo[5,1-c][1,2,4]triazines by azocoupling reaction.
Synthesis and supramolecular properties of regioisomers of mononaphthylallyl derivatives of γ-cyclodextrin
- Markéta Bláhová,
- Sergey K. Filippov,
- Lubomír Kováčik,
- Jiří Horský,
- Simona Hybelbauerová,
- Zdenka Syrová,
- Tomáš Křížek and
- Jindřich Jindřich
Beilstein J. Org. Chem. 2017, 13, 2509–2520, doi:10.3762/bjoc.13.248
- regioisomers in similar ways as González-Gaitano [21] and as we did for Cin-α-CD [20]. The temperature was raised from 5 °C to 65 °C (5 °C steps) across 2.5 h, which led to substantial changes in sizes of the aggregates (Figure 3). A shift of the correlation curve, caused by the change of viscosity, is
Graphical Abstract
Scheme 1: Preparation of 2I-O-, 3I-O- and 6I-O-naphthylallyl derivatives of γ-CD by cross-metathesis.
Scheme 2: Preparation of 2-O-, 3-O- and 6-O-NA derivatives of γ-CD by direct alkylation (see Table 1 for the yields ...
Figure 1: Volume-weighted distribution functions for water solutions of 2-O- (2a), 3-O- (2b), and 6-O- (2c) N...
Figure 2: Distribution functions for 2-O- (2a), 3-O- (2b), and 6-O- (2c) NA-γ-CD regioisomers in 50% MeOH (v/...
Figure 3: Volume-weighted distribution functions for the 3-O- (2b) and 6-O- (2c) NA-γ-CD regioisomer at diffe...
Figure 4: Effect of increasing concentration and sonication on the morphology of the 3-O-derivative 2b. A to ...
Figure 5: Effect of increasing concentration and sonication on the morphology of the 2-O-derivative 2a. A: 2 ...
Figure 6: Effect of increasing concentration and sonication on the morphology of the 6-O-derivative 2c. A: 0....
Figure 7: Heat change for injection per mole of NA-γ-CD added as a function of the total concentration of NA-...
Figure 8: 1H NMR spectra of 2-O-derivative 2a in D2O at concentrations of 100, 10, and 1 mM.
Figure 9: 1H NMR spectra of 3-O-derivative 2b in D2O at concentrations of 100, 10, and 1 mM.
Figure 10: Putative objects and interactions in naphthylallyl-γ-CD solution, depicted schematically for 6I-O-n...
One-pot three-component route for the synthesis of S-trifluoromethyl dithiocarbamates using Togni’s reagent
- Azim Ziyaei Halimehjani,
- Martin Dračínský and
- Petr Beier
Beilstein J. Org. Chem. 2017, 13, 2502–2508, doi:10.3762/bjoc.13.247
- fields of pharmaceuticals, agrochemicals, and materials sciences. The key properties such as metabolic and chemical stability, polarity, bioavailability, viscosity and lipophilicity can be altered in molecules containing the CF3 group in comparison with the nonfluorinated analogues. Numerous methods have
Graphical Abstract
Scheme 1: Synthetic routes for the preparation of trifluoromethyl dithiocarbamates.
Scheme 2: Synthesis of S-trifluoromethyl dithiocarbamates. Isolated yields are given in parentheses.
Scheme 3: Formation of benzyl isothiocyanate in a reaction with benzylamine.
Figure 1: Variable temperature 1H NMR spectra of compound 4c (CH2 region on the left and CH3 region on the ri...
Figure 2: The Eyring plot obtained for the rotation around the N–C bond in compound 4c.
Figure 3: The optimized structure of compound 4b (left) and the transition state structure for the rotation a...
Hydrolysis, polarity, and conformational impact of C-terminal partially fluorinated ethyl esters in peptide models
- Vladimir Kubyshkin and
- Nediljko Budisa
Beilstein J. Org. Chem. 2017, 13, 2442–2457, doi:10.3762/bjoc.13.241
- aqueous phosphate buffer (right, 50 mM buffer, pH 7.0) samples. Recorded at 298 K and 100 μM peptide. Conformational analysis of the peptides by 1H DOSY NMR (D2O, 298 K). The theoretical values were calculated according to Equation 5 assuming deuterium oxide viscosity and 298 K. Hydrolysis of the C
Graphical Abstract
Figure 1: A. Dependence of the lipophilicity (logP) on the number of fluorine atoms in a partially fluorinate...
Scheme 1: Synthesis of the model compounds.
Figure 2: Kinetics of the C-terminal ester hydrolysis.
Figure 3: Partitioning of the esters 1–5 between octan-1-ol and water. Insert: comparison with the other part...
Scheme 2: Amide isomerism in the N-acetylprolyl fragment.
Figure 4: Enhancement of the trans/cis thermodynamic preferences in the ester models as a function of the sol...
Scheme 3: A. Four-state conformational equilibrium model used by Siebler et al. [72] for explanations of the elev...
Scheme 4: Elevation of the trans/cis ratio in derivatives of N-acyl proline may result from the enhanced n→π*...
Scheme 5: Synthesis of the model peptides.
Figure 5: Mean residue molar circular dichroism (Δε) of peptides 8–10 in methanol (left) and aqueous phosphat...
Figure 6: Conformational analysis of the peptides by 1H DOSY NMR (D2O, 298 K). The theoretical values were ca...
Figure 7: Hydrolysis of the C-terminal 2,2-difluoroethyl esters of the oligopeptides in buffered deuterium ox...
β-Cyclodextrin- and adamantyl-substituted poly(acrylate) self-assembling aqueous networks designed for controlled complexation and release of small molecules
- Liang Yan,
- Duc-Truc Pham,
- Philip Clements,
- Stephen F. Lincoln,
- Jie Wang,
- Xuhong Guo and
- Christopher J. Easton
Beilstein J. Org. Chem. 2017, 13, 1879–1892, doi:10.3762/bjoc.13.183
- viscosity of the network as shown by ITC, 1H NMR and UV–vis spectroscopy, and rheological studies. Such networks potentially form a basis for the design of controlled drug release systems. Keywords: controlled release; cyclodextrin; network; poly(acrylate); self-assembly; Introduction The formation of
- substituent and network formation being outweighed by the entropy gain arising from displacement of water from the β-CDen annulus by the adamantyl group of ADddn and its dodecyl tether (under the titration conditions the solutions remain fluid whereas at higher concentrations the solution viscosity increases
- each dye was 2.00 × 10−3 mol dm−3 and the overall concentration of substituted poly(acrylate)s was 1.14–1.20 wt %. (These hydrogel compositions are identical to those used in the dye release studies discussed below, and are presented in Table S1, Supporting Information File 1.) The viscosity variation
Graphical Abstract
Figure 1: β-Cyclodextrin- and adamantyl-substituted poly(acrylate)s PAAβ-CDen, PAAADen, PAAADhn, and PAAADddn...
Figure 2: ITC data for the PAAβ-CDen/PAAADen, system obtained in aqueous Na2HPO4/KH2PO4 pH 7.0 buffer at I = ...
Figure 3: ITC data for the PAAβ-CDen/PAAADddn system obtained in aqueous Na2HPO4/KH2PO4 pH 7.0 buffer at I = ...
Figure 4: Representation of ditopic complexation of an ADddn substituent of PAAADddn, by two β-CDen substitue...
Figure 5: 2D NOESY 1H NMR spectrum of 0.44 wt % PAAβ-CDen ([β-CDen] = 2.0 × 10−3 mol dm−3) and 0.60 wt % PAAA...
Figure 6: (a) Molar absorbance variation of 1.5 cm3 of a EO solution ([EO] = 2.00 × 10−5 mol dm−3) with 20 se...
Figure 7: (a) Molar absorbance variation of 1.5 cm3 of a EO solution ([EO] = 2.00 × 10−5 mol dm−3) with 20 se...
Figure 8: Speciation plot with [β-CDen]total = 100% for the PAAβ-CDen/PAAADhn/EO system.
Figure 9: 2D NOESY 1H NMR spectrum of MR ([MR] = 2.0 × 10−3 mol dm−3) in solution with PAAβ-CDen (0.78 wt %, ...
Figure 10: Viscosity variations at a 0.03 s−1 shear rate of 1.14 wt % PAAβ-CDen/PAAADen, 1.18 wt % PAAβ-CDen/P...
Figure 11: Representation of dye complexation in the PAAβ-CDen/PAAADen and PAAβ-CDen/PAAADhn networks.
Figure 12: Release profiles for EO (i), MO (ii) and MR (iii) from aqueous (a) Na2HPO4/KH2PO4 buffer alone, (b)...
Automating multistep flow synthesis: approach and challenges in integrating chemistry, machines and logic
- Chinmay A. Shukla and
- Amol A. Kulkarni
Beilstein J. Org. Chem. 2017, 13, 960–987, doi:10.3762/bjoc.13.97
- variables are the most critical part of the process control. The process variables that are often measured are temperature, pressure, flow, liquid level, density, composition, pH and viscosity. Details of different sensors or transmitters for measuring these variables can be found in standard process
Graphical Abstract
Figure 1: A number of experiments for various optimization algorithms [46].
Figure 2: Symbols used for block and P&ID diagrams.
Scheme 1: Multistep synthesis of olanzapine (Hartwig et al. [10])
Figure 3: (A) Block diagram representation of the process shown in Scheme 1, (B) piping and instrumentation diagram o...
Scheme 2: Multistep flow synthesis for tamoxifen (Murray et al. [11]).
Figure 4: (A) Block diagram representation of the process shown in Scheme 2, (B) piping and instrumentation diagram o...
Figure 5: (A) Block diagram representation of the process shown in Scheme 3, (B) piping and instrumentation diagram o...
Scheme 3: Multistep flow synthesis of rufinamide (Zhang et al. [14]).
Figure 6: (A) Block diagram representation of the process shown in Scheme 4, (B) piping and instrumentation diagram o...
Scheme 4: Multistep synthesis for (±)-Oxomaritidine (Baxendale et al. [9]).
Figure 7: (A) Block diagram representation of the process shown in Scheme 5, (B) piping and instrumentation diagram o...
Scheme 5: Multistep synthesis for ibuprofen (Snead and Jamison [60]).
Scheme 6: Multistep synthesis for cinnarizine and buclizine derivatives (Borukhova et al. [23])
Figure 8: (A) Block diagram representation of the process shown in Scheme 6, (B) piping and instrumentation diagram o...
Scheme 7: Multistep synthesis for (S)-rolipram (Tsubogo et al. [4])
Figure 9: (A) Block diagram representation of the process shown in Scheme 7 (colours for each reactor shows different...
Figure 10: (A) Block diagram representation of the process shown in Scheme 8, (B) piping and instrumentation diagram o...
Scheme 8: Multistep synthesis for amitriptyline (Kupracz and Kirschning [7]).
Continuous-flow processes for the catalytic partial hydrogenation reaction of alkynes
- Carmen Moreno-Marrodan,
- Francesca Liguori and
- Pierluigi Barbaro
Beilstein J. Org. Chem. 2017, 13, 734–754, doi:10.3762/bjoc.13.73
- viscosity; v linear velocity), thanks to the high permeability coefficient k > 0.25 μm2, which is proportional to the macroporous size D2 [113]. The catalytic performance of these monoliths has been compared in continuous flow as a single piece or packed-bed (ground monolith 60–120 μm) and in batch
Graphical Abstract
Scheme 1: Common reaction pathways for alkyne hydrogenation reactions.
Figure 1: Schematic representation of most common reactor types for batch and continuous-flow partial hydroge...
Figure 2: Schematic representation of flow regimes in microchannels; (a) bubbly flow, (b) slug/Taylor or segm...
Figure 3: Sketch of typical continuous flow apparatus for liquid-phase catalytic alkynes hydrogenation reacti...
Scheme 2: Hydrogenation reactions of terminal alkynes with potential products and labelling scheme.
Figure 4: Structure of Pd@mpg-C3N4 (a), Pd(HHDMA)@C (b), Pd(Pb)@CaCO3 (c) and Pd@Al2O3 (d) catalysts. The str...
Figure 5: Sketch of composition (left) and optical image of Pd@MonoBor monolithic reactor (right). Adapted wi...
Figure 6: X-ray tomography 3D-reconstruction image of MonoBor [133]. Unpublished image from the authors.
Figure 7: Representative TEM image of titanate nanotubes with immobilized PdNP (arrows). Adapted with permiss...
Figure 8: Conversion and selectivity vs. time-on-stream for the continuous-flow hydrogenation of 6 over Pd@Mo...
Figure 9: Continuous-flow hydrogenation of 3, 6 and 7 over different catalytic reactor systems. Data from ref...
Scheme 3: Hydrogenation reactions of internal alkynes with potential products and labelling scheme.
Figure 10: Continuous-flow hydrogenation of 11 over Pd@MonoBor catalyst. a) Conversion and selectivity as a fu...
Figure 11: Conversion and selectivity vs time-on-stream for the continuous-flow hydrogenation of 11 over Pd@Mo...
Figure 12: Continuous-flow hydrogenation reaction of 11 over packed-bed catalysts. Adapted with permission fro...
Figure 13: Images of the bimodal TiO2 monolith with well-defined macroporosity: (a, b) optical; (c) X-ray tomo...
Figure 14: Selectivity of the continuous-flow partial hydrogenation reaction of 3 and 4 over packed-bed Pd cat...
Highly reactive, liquid diacrylamides via synergistic combination of spatially arranged curing moieties
- Maximilian Maier,
- Magnus S. Schmidt,
- Markus Ringwald and
- Christoph P. Fik
Beilstein J. Org. Chem. 2017, 13, 372–383, doi:10.3762/bjoc.13.40
- -acryl, N-allyl and/or N-alkyl groups were prepared via two-step syntheses and characterized by 1H/13C NMR-spectra, refractive index (RI) and viscosity measurements. Photo DSC measurements on activated samples provided reactivity parameters ∆Hp, Rp,max and tmax, while FTIR spectra before and after curing
- ; Introduction The selection of suitable monomers is a critical step for any free-radical polymerization approach. Particularly for (in situ) photo-induced polymerizations, monomers should comprise sufficient solubility in a given matrix, moderate viscosity, matching refractive indices as well as an optimized
- . RIs of 1 and 4 are thus close to that of aromatic crosslinkers such as ethoxylated bisphenol-A dimethacrylate, EBPADMA (2 ethoxy groups, nD20 1.525, η ≈ 900 mPa·s), but at a significantly lower viscosity and with the important difference, that all double bonds can take part in polymerization reactions
Graphical Abstract
Scheme 1: Top: Overview of the synthesized crosslinkers 1–6 and their correlation to each other via formal re...
Scheme 2: Synthetic pathways to structurally related compounds 1–6.
Scheme 3: Byproducts 8a and 9a.
Scheme 4: Synthetic pathways towards the planned cis-intermediate 19.
Scheme 5: Comparison of structural elements of 1–6 in the 1H NMR spectra (400 MHz).
Figure 1: Refractive indices (RI) and viscosities (η) of crosslinkers 1–6 (* solid at room temperature).
Figure 2: Exemplary photo-DSC plots for the curing of 1 and 3–6 at 37 °C.
Figure 3: tmax for the curing of 1 and 3–6 at 37 °C (* no polymerization heat detected).
Figure 4: Rp, max for the curing of 1–6 at 37 °C for a) top: ∆Hp of allyl groups = 87.5 kJ·mol−1 and b) botto...
Figure 5: Polymerization heat, ∆Hp for the curing of 1–6 at 37 °C (* no polymerization heat detected).
Figure 6: FTIR spectra of 1–6 before (top) and after (bottom) curing; the arrows indicate emerging, character...
Scheme 6: Proposed reaction pathways for the intramolecular propagation within 1.
Figure 7: Flexural strength (FS) and E-modulus of cured crosslinkers 1–6; letters refer to statistical groups...
Extrusion – back to the future: Using an established technique to reform automated chemical synthesis
- Deborah E. Crawford
Beilstein J. Org. Chem. 2017, 13, 65–75, doi:10.3762/bjoc.13.9
- turn alters the properties of the materials [6]. Initially, the polymer industry employed only batch mixers to synthesise polymers and carry out post synthetic modification (PSM), however, this proved difficult and inefficient. This was due to a dramatic increase or change in the viscosity and rheology
- of the material, a common feature of REX, and therefore as reactions proceed, they can become very difficult to mix efficiently, leading to low conversions. A second problem associated with the change in viscosity is the resultant poor heat transfer, meaning that longer heating times are required
- viscosity, rheology and the kinetics of formation also. The authors report that a reaction between 4,4’-diphenylmethane diisocyanate, polycaprolactonediol and 1,4-butanediol takes place in a twin screw extruder, employing a screw speed of 15 rpm and a temperature of 60 °C [25]. This transformation was
Graphical Abstract
Figure 1: Typical pilot scale single screw extruder (left) and a laboratory scale twin screw extruder (right)....
Figure 2: PTFE screw employed in single screw extrusion, with increasing root diameter (RD) from 45 mm to 95 ...
Figure 3: Modulated stainless steel intermeshing co-rotating screws employed typically in twin screw extrusio...
Scheme 1: Polymerisation of styrene using s-BuLi as an initiator.
Scheme 2: Telescoping process of the formation of polystyrene, followed by post polymerisation functionalisat...
Scheme 3: Proposed mechanism for the branching of polylactide. Adapted from [23].
Scheme 4: Chemical reaction between isocyanate and an alcohol to form polyurethane.
Figure 4: Representative diagram explaining the process involved in step growth polymerisation, which involve...
Scheme 5: Generic polycondensation reaction to produce polyamides.
Figure 5: Comparison of choline chloride/D-fructose DES prepared via twin screw extrusion (left) and conventi...
Scheme 6: Synthesis of HKUST-1, ZIF-8 and Al(fumarate)OH by twin screw extrusion. Adapted from [2].
Figure 6: Synthesis of Ni(NCS)2(PPh3)2 and [Ni(salen)] by twin screw extrusion. Adapted from [2].
Poly(ethylene glycol)s as grinding additives in the mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins
- Andrea Mascitti,
- Massimiliano Lupacchini,
- Ruben Guerra,
- Ilya Taydakov,
- Lucia Tonucci,
- Nicola d’Alessandro,
- Frederic Lamaty,
- Jean Martinez and
- Evelina Colacino
Beilstein J. Org. Chem. 2017, 13, 19–25, doi:10.3762/bjoc.13.3
- reaction time (3 h instead of 2 h), when ‘pre-treated’ PEGs were used instead of ‘unfiltered’ PEGs (Table 1, entries 3 and 8). This observation suggested that changes in the ‘physical state of the system could be induced by specific interactions with PEG polymers and influenced both by the viscosity and
- reactants. Decreased and comparable yields were also observed by reducing the PEG chain length (Table 1, entry 13) and by using glycerol. It is also worth noting here that not only viscosity, but any modification of the physical state of the system impacted the outcome of the reaction. Indeed, HO-PEG-600-OH
Graphical Abstract
Scheme 1: PEG-assisted grinding strategy for the preparation of 3,5-disubstituted hydantoins.
Towards the development of continuous, organocatalytic, and stereoselective reactions in deep eutectic solvents
- Davide Brenna,
- Elisabetta Massolo,
- Alessandra Puglisi,
- Sergio Rossi,
- Giuseppe Celentano,
- Maurizio Benaglia and
- Vito Capriati
Beilstein J. Org. Chem. 2016, 12, 2620–2626, doi:10.3762/bjoc.12.258
- back through DES due to the difference in the viscosity of the two phases, thereby generating a upper organic phase (blue in the picture) which finally ended into the organic phase of the larger tube, that was continuously pumped into the DES phase to realize a closed cycle. In set-up II, the mixture
Graphical Abstract
Scheme 1: L-Proline-promoted stereoselective aldol reaction in DES.
Figure 1: Experimental set-up I: test tube (d = 0.5 cm); flow 1 mL/min; DES (1.5 mL); L-proline/DES = 130 mg/...
Scheme 2: Aldol reaction under continuous flow conditions in DESs.
Protonated paramagnetic redox forms of di-o-quinone bridged with p-phenylene-extended TTF: A EPR spectroscopy study
- Nikolay O. Chalkov,
- Vladimir K. Cherkasov,
- Gleb A. Abakumov,
- Andrey G. Starikov and
- Viacheslav A. Kuropatov
Beilstein J. Org. Chem. 2016, 12, 2450–2456, doi:10.3762/bjoc.12.238
- increase in the viscosity of the solvent. According to these data, (1·−)H2 belongs to class III of Robin–Day classification [15] of mixed valence systems. Thus, the molecule does not have distinct catechol or semiquinone oxidation states for the dioxolene moieties on the termini, i.e., an additional
Graphical Abstract
Figure 1: The structural formula of acceptor–donor–acceptor triad 1.
Figure 2: The EPR spectrum of (1·)H in CHCl3, 293 K: a) experimental and b) experimental + D2O.
Scheme 1: Disproportionation of the protonated semiquinones in solution.
Scheme 2: Paramagnetic reduced protonated derivatives of the quinone 2.
Figure 3: The EPR spectrum of (1·)H3 in CHCl3, 293 K: a) experimental, b) simulated, c) experimental + D2O an...
Figure 4: The EPR spectrum of (1·−)H2 THF, 293 K: a) experimental and b) experimental + D2O). Magnified side ...
Figure 5: The well-resolved EPR spectrum of (1·−)H2 in dimethoxyethane (diluted solution), 273 K: a) experime...
A flow reactor setup for photochemistry of biphasic gas/liquid reactions
- Josef Schachtner,
- Patrick Bayer and
- Axel Jacobi von Wangelin
Beilstein J. Org. Chem. 2016, 12, 1798–1811, doi:10.3762/bjoc.12.170
- effects on reaction rates and selectivities. Furthermore, specific properties of the reagents and solvents (viscosity, surface tension, gas solubility) will be critical to the dispersion and slug flow formation. Light source The benefit of microreaction technologies applied to photochemical processes is
- transfer coefficients compared to traditional stirred tanks [39]. Depending on the flow rates of gas and liquid phases, their ratio, the solvent viscosity and the reactor dimensions, different flow pattern can be obtained. The so-called slug flow leads to very efficient irradiation but also other spatial
- capillary tubing is dependent on the length and gauge of the capillary and the flow rate of the solution. If the dynamic viscosity of the solution is known, the pressure gradient can be calculated from the Hagen–Poiseuille equation (Scheme 4). Temperature control The microreactor system is equipped with a
Graphical Abstract
Figure 1: The challenge of mixing the three dispersed entities gas, liquid, and light for photochemical appli...
Scheme 1: Mutual interdependencies of critical reaction and reactor parameters.
Scheme 2: Blueprint of the home-built microflow photoreactor; schematic illustration of the reactor setup wit...
Figure 2: Total absorbance of methylene blue solutions in acetonitrile according to the Beer-Lambert law: Eλ ...
Figure 3: Red (λmax = 633 nm), blue (λmax = 448 nm), green (λmax = 520 nm) and white (λmax = 620 nm) LEDs mou...
Figure 4: Overlap of absorption spectrum of methylene blue in acetonitrile and emission spectra of reasonably...
Figure 5: Emission spectra of different LEDs; red (λmax = 633 nm), blue (λmax = 448 nm), green (λmax = 520 nm...
Scheme 3: Slug flow conditions of two-phase gas-liquid mixtures. Photograph of a slug flow of a solution of m...
Figure 6: Photograph of the operating flow reactor, irradiated with white LEDs, filled with a solution of met...
Scheme 4: Schematic illustration of a reactor tube (length l, inner diameter d) and pressure gradient Δp acco...
Scheme 5: Reaction types of organic molecules with singlet oxygen.
Figure 7: Home-made flow reactor and peripheral devices for photochemical reactions at light/liquid/gas inter...
Scheme 6: Photooxygenation of N-methyl-1,2,3,6-tetrahydrophthalimide and reductive work-up to alcohol 3a.
Figure 8: Conversion vs methylene blue sensitizer concentration. Reactions at constant flow rates in acetonit...
Figure 9: Reaction progress at different residence times in flow and batch reactions. Flow: reactions at diff...
Scheme 7: Oxidation of N-methyl-1,2,3,6-tetrahydro-3-acetamidophthalimide and reductive work-up to alcohol 3b....
Rearrangements of organic peroxides and related processes
- Ivan A. Yaremenko,
- Vera A. Vil’,
- Dmitry V. Demchuk and
- Alexander O. Terent’ev
Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162
Graphical Abstract
Figure 1: The named transformations considered in this review.
Scheme 1: The Baeyer–Villiger oxidation.
Scheme 2: The general mechanism of the peracid-promoted Baeyer–Villiger oxidation.
Scheme 3: General mechanism of the Lewis acid-catalyzed Baeyer–Villiger rearrangement.
Scheme 4: The theoretically studied mechanism of the BV oxidation reaction promoted by H2O2 and the Lewis aci...
Scheme 5: Proton movements in the transition states of the Baeyer–Villiger oxidation.
Scheme 6: The dependence of the course of the Baeyer–Villiger oxidation on the type of O–O-bond cleavage in t...
Scheme 7: The acid-catalyzed Baeyer–Villiger oxidation of cyclic epoxy ketones 22.
Scheme 8: Oxidation of isophorone oxide 29.
Scheme 9: Synthesis of acyl phosphate 32 from acyl phosphonate 31.
Scheme 10: Synthesis of aflatoxin B2 (36).
Scheme 11: The Baeyer–Villiger rearrangement of ketones 37 to lactones 38.
Scheme 12: Synthesis of 3,4-dimethoxybenzoic acid (40) via Baeyer–Villiger oxidation.
Scheme 13: Oxone transforms α,β-unsaturated ketones 43 into vinyl acetates 44.
Scheme 14: The Baeyer–Villiger oxidation of ketones 45 using diaryl diselenide and hydrogen peroxide.
Scheme 15: Baeyer–Villiger oxidation of (E)-2-methylenecyclobutanones.
Scheme 16: Oxidation of β-ionone (56) by H2O2/(BnSe)2 with formation of (E)-2-(2,6,6-trimethylcyclohex-1-en-1-...
Scheme 17: The mechanism of oxidation of ketones 58a–f by hydrogen peroxide in the presence of arsonated polys...
Scheme 18: Oxidation of ketone (58b) by H2O2 to 6-methylcaprolactone (59b) catalyzed by Pt complex 66·BF4.
Scheme 19: Oxidation of ketones 67 with H2O2 in the presence of [(dppb}Pt(µ-OH)]22+.
Scheme 20: The mechanism of oxidation of ketones 67 in the presence of [(dppb}Pt(µ-OH)]22+ and H2O2.
Scheme 21: Oxidation of benzaldehydes 69 in the presence of the H2O2/MeReO3 system.
Scheme 22: Oxidation of acetophenones 72 in the presence of the H2O2/MeReO3 system.
Scheme 23: Baeyer–Villiger oxidation of 2-adamantanone (45c) in the presence of Sn-containing mesoporous silic...
Scheme 24: Aerobic Baeyer–Villiger oxidation of ketones 76 using metal-free carbon.
Scheme 25: A regioselective Baeyer-Villiger oxidation of functionalized cyclohexenones 78 into a dihydrooxepin...
Scheme 26: The oxidation of aldehydes and ketones 80 by H2O2 catalyzed by Co4HP2Mo15V3O62.
Scheme 27: The cleavage of ketones 82 with hydrogen peroxide in alkaline solution.
Scheme 28: Oxidation of ketones 85 to esters 86 with H2O2–urea in the presence of KHCO3.
Scheme 29: Mechanism of the asymmetric oxidation of cyclopentane-1,2-dione 87a with the Ti(OiPr)4/(+)DET/t-BuO...
Scheme 30: The oxidation of cis-4-tert-butyl-2-fluorocyclohexanone (93) with m-chloroperbenzoic acid.
Scheme 31: The mechanism of the asymmetric oxidation of 3-substituted cyclobutanone 96a in the presence of chi...
Scheme 32: Enantioselective Baeyer–Villiger oxidation of cyclic ketones 98.
Scheme 33: Regio- and enantioselective Baeyer–Villiger oxidation of cyclic ketones 101.
Scheme 34: The proposed mechanism of the Baeyer–Villiger oxidation of acetal 105f.
Scheme 35: Synthesis of hydroxy-10H-acridin-9-one 117 from tetramethoxyanthracene 114.
Scheme 36: The Baeyer–Villiger oxidation of the fully substituted pyrrole 120.
Scheme 37: The Criegee rearrangement.
Scheme 38: The mechanism of the Criegee reaction of a peracid with a tertiary alcohol 122.
Scheme 39: Criegee rearrangement of decaline ethylperoxoate 127 into ketal 128.
Scheme 40: The ionic cleavage of 2-methoxy-2-propyl perester 129.
Scheme 41: The Criegee rearrangement of α-methoxy hydroperoxide 136.
Scheme 42: Synthesis of enol esters and acetals via the Criegee rearrangement.
Scheme 43: Proposed mechanism of the transformation of 1-hydroperoxy-2-oxabicycloalkanones 147a–d.
Scheme 44: Transformation of 3-hydroxy-1,2-dioxolanes 151 into diketone derivatives 152.
Scheme 45: Criegee rearrangement of peroxide 153 with the mono-, di-, and tri-O-insertion.
Scheme 46: The sequential Criegee rearrangements of adamantanes 157a,b.
Scheme 47: Synthesis of diaryl carbonates 160a–d from triarylmethanols 159a–d through successive oxygen insert...
Scheme 48: The synthesis of sesquiterpenes 162 from ketone 161 with a Criegee rearrangement as one key step.
Scheme 49: Synthesis of trans-hydrindan derivatives 164, 165.
Scheme 50: The Hock rearrangement.
Scheme 51: The general scheme of the cumene process.
Scheme 52: The Hock rearrangement of aliphatic hydroperoxides.
Scheme 53: The mechanism of solvolysis of brosylates 174a–c and spiro cyclopropyl carbinols 175a–c in THF/H2O2....
Scheme 54: The fragmentation mechanism of hydroperoxy acetals 178 to esters 179.
Scheme 55: The acid-catalyzed rearrangement of phenylcyclopentyl hydroperoxide 181.
Scheme 56: The peroxidation of tertiary alcohols in the presence of a catalytic amount of acid.
Scheme 57: The acid-catalyzed reaction of bicyclic secondary alcohols 192 with hydrogen peroxide.
Scheme 58: The photooxidation of 5,6-disubstituted 3,4-dihydro-2H-pyrans 196.
Scheme 59: The oxidation of tertiary alcohols 200a–g, 203a,b, and 206.
Scheme 60: Transformation of functional peroxide 209 leading to 2,3-disubstitued furans 210 in one step.
Scheme 61: The synthesis of carbazoles 213 via peroxide rearrangement.
Scheme 62: The construction of C–N bonds using the Hock rearrangement.
Scheme 63: The synthesis of moiety 218 from 217 which is a structural motif in the antitumor–antibiotic of CC-...
Scheme 64: The in vivo oxidation steps of cholesterol (219) by singlet oxygen.
Scheme 65: The proposed mechanism of the rearrangement of cholesterol-5α-OOH 220.
Scheme 66: Photochemical route to artemisinin via Hock rearrangement of 223.
Scheme 67: The Kornblum–DeLaMare rearrangement.
Scheme 68: Kornblum–DeLaMare transformation of 1-phenylethyl tert-butyl peroxide (225).
Scheme 69: The synthesis 4-hydroxyenones 230 from peroxide 229.
Scheme 70: The Kornblum–DeLaMare rearrangement of peroxide 232.
Scheme 71: The reduction of peroxide 234.
Scheme 72: The Kornblum–DeLaMare rearrangement of endoperoxide 236.
Scheme 73: The rearrangement of peroxide 238 under Kornblum–DeLaMare conditions.
Scheme 74: The proposed mechanism of rearrangement of peroxide 238.
Scheme 75: The Kornblum–DeLaMare rearrangement of peroxides 242a,b.
Scheme 76: The base-catalyzed rearrangements of bicyclic endoperoxides having electron-withdrawing substituent...
Scheme 77: The base-catalyzed rearrangements of bicyclic endoperoxides 249a,b having electron-donating substit...
Scheme 78: The base-catalyzed rearrangements of bridge-head substituted bicyclic endoperoxides 251a,b.
Scheme 79: The Kornblum–DeLaMare rearrangement of hydroperoxide 253.
Scheme 80: Synthesis of β-hydroxy hydroperoxide 254 from endoperoxide 253.
Scheme 81: The amine-catalyzed rearrangement of bicyclic endoperoxide 263.
Scheme 82: The base-catalyzed rearrangement of meso-endoperoxide 268 into 269.
Scheme 83: The photooxidation of 271 and subsequent Kornblum–DeLaMare reaction.
Scheme 84: The Kornblum–DeLaMare rearrangement as one step in the oxidation reaction of enamines.
Scheme 85: The Kornblum–DeLaMare rearrangement of 3,5-dihydro-1,2-dioxenes 284, 1,2-dioxanes 286, and tert-but...
Scheme 86: The Kornblum–DeLaMare rearrangement of epoxy dioxanes 290a–d.
Scheme 87: Rearrangement of prostaglandin H2 292.
Scheme 88: The synthesis of epicoccin G (297).
Scheme 89: The Kornblum–DeLaMare rearrangement used in the synthesis of phomactin A.
Scheme 90: The Kornblum–DeLaMare rearrangement in the synthesis of 3H-quinazolin-4-one 303.
Scheme 91: The Kornblum–DeLaMare rearrangement in the synthesis of dolabriferol (308).
Scheme 92: Sequential transformation of 3-substituted 2-pyridones 309 into 3-hydroxypyridine-2,6-diones 311 in...
Scheme 93: The Kornblum–DeLaMare rearrangement of peroxide 312 into hydroxy enone 313.
Scheme 94: The Kornblum–DeLaMare rearrangement in the synthesis of polyfunctionalized carbonyl compounds 317.
Scheme 95: The Kornblum–DeLaMare rearrangement in the synthesis of (Z)-β-perfluoroalkylenaminones 320.
Scheme 96: The Kornblum–DeLaMare rearrangement in the synthesis of γ-ketoester 322.
Scheme 97: The Kornblum–DeLaMare rearrangement in the synthesis of diterpenoids 326 and 328.
Scheme 98: The synthesis of natural products hainanolidol (331) and harringtonolide (332) from peroxide 329.
Scheme 99: The synthesis of trans-fused butyrolactones 339 and 340.
Scheme 100: The synthesis of leucosceptroid C (343) and leucosceptroid P (344) via the Kornblum–DeLaMare rearra...
Scheme 101: The Dakin oxidation of arylaldehydes or acetophenones.
Scheme 102: The mechanism of the Dakin oxidation.
Scheme 103: A solvent-free Dakin reaction of aromatic aldehydes 356.
Scheme 104: The organocatalytic Dakin oxidation of electron-rich arylaldehydes 358.
Scheme 105: The Dakin oxidation of electron-rich arylaldehydes 361.
Scheme 106: The Dakin oxidation of arylaldehydes 358 in water extract of banana (WEB).
Scheme 107: A one-pot approach towards indolo[2,1-b]quinazolines 364 from indole-3-carbaldehydes 363 through th...
Scheme 108: The synthesis of phenols 367a–c from benzaldehydes 366a-c via acid-catalyzed Dakin oxidation.
Scheme 109: Possible transformation paths of the highly polarized boric acid coordinated H2O2–aldehyde adduct 3...
Scheme 110: The Elbs oxidation of phenols 375 to hydroquinones.
Scheme 111: The mechanism of the Elbs persulfate oxidation of phenols 375 affording p-hydroquinones 376.
Scheme 112: Oxidation of 2-pyridones 380 under Elbs persulfate oxidation conditions.
Scheme 113: Synthesis of 3-hydroxy-4-pyridone (384) via an Elbs oxidation of 4-pyridone (382).
Scheme 114: The Schenck rearrangement.
Scheme 115: The Smith rearrangement.
Scheme 116: Three main pathways of the Schenck rearrangement.
Scheme 117: The isomerization of hydroperoxides 388 and 389.
Scheme 118: Trapping of dioxacyclopentyl radical 392 by oxygen.
Scheme 119: The hypothetical mechanism of the Schenck rearrangement of peroxide 394.
Scheme 120: The autoxidation of oleic acid (397) with the use of labeled isotope 18O2.
Scheme 121: The rearrangement of 18O-labeled hydroperoxide 400 under an atmosphere of 16O2.
Scheme 122: The rearrangement of the oleate-derived allylic hydroperoxides (S)-421 and (R)-425.
Scheme 123: Mechanisms of Schenck and Smith rearrangements.
Scheme 124: The rearrangement and cyclization of 433.
Scheme 125: The Wieland rearrangement.
Scheme 126: The rearrangement of bis(triphenylsilyl) 439 or bis(triphenylgermyl) 441 peroxides.
Scheme 127: The oxidative transformation of cyclic ketones.
Scheme 128: The hydroxylation of cyclohexene (447) in the presence of tungstic acid.
Scheme 129: The oxidation of cyclohexene (447) under the action of hydrogen peroxide.
Scheme 130: The reaction of butenylacetylacetone 455 with hydrogen peroxide.
Scheme 131: The oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 132: The proposed mechanism for the oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 133: The rearrangement of ozonides.
Scheme 134: The acid-catalyzed oxidative rearrangement of malondialdehydes 462 under the action of H2O2.
Scheme 135: Pathways of the Lewis acid-catalyzed cleavage of dialkyl peroxides 465 and ozonides 466.
Scheme 136: The mechanism of the transformation of (tert-butyldioxy)cyclohexanedienones 472.
Scheme 137: The synthesis of Vitamin K3 from 472a.
Scheme 138: Proposed mechanism for the transformation of 478d into silylated endoperoxide 479d.
Scheme 139: The rearrangement of hydroperoxide 485 to form diketone 486.
Scheme 140: The base-catalyzed rearrangement of cyclic peroxides 488a–g.
Scheme 141: Synthesis of chiral epoxides and aldols from peroxy hemiketals 491.
Scheme 142: The multistep transformation of (R)-carvone (494) to endoperoxides 496a–e.
Scheme 143: The decomposition of anthracene endoperoxide 499.
Scheme 144: Synthesis of esters 503 from aldehydes 501 via rearrangement of peroxides 502.
Scheme 145: Two possible paths for the base-promoted decomposition of α-azidoperoxides 502.
Scheme 146: The Story decomposition of cyclic diperoxide 506a.
Scheme 147: The Story decomposition of cyclic triperoxide 506b.
Scheme 148: The thermal rearrangement of endoperoxides A into diepoxides B.
Scheme 149: The transformation of peroxide 510 in the synthesis of stemolide (511).
Scheme 150: The possible mechanism of the rearrangement of endoperoxide 261g.
Scheme 151: The photooxidation of indene 517.
Scheme 152: The isomerization of ascaridole (523).
Scheme 153: The isomerization of peroxide 525.
Scheme 154: The thermal transformation of endoperoxide 355.
Scheme 155: The photooxidation of cyclopentadiene (529) at a temperature higher than 0 °C.
Scheme 156: The thermal rearrangement of endoperoxides 538a,b.
Scheme 157: The transformation of peroxides 541.
Scheme 158: The thermal rearrangements of strained cyclic peroxides.
Scheme 159: The thermal rearrangement of diacyl peroxide 551 in the synthesis of C4-epi-lomaiviticin B core 553....
Scheme 160: The 1O2 oxidation of tryptophan (554) and rearrangement of dioxetane intermediate 555.
Scheme 161: The Fe(II)-promoted cleavage of aryl-substituted bicyclic peroxides.
Scheme 162: The proposed mechanism of the Fe(II)-promoted rearrangement of 557a–c.
Scheme 163: The reaction of dioxolane 563 with Fe(II) sulfate.
Scheme 164: Fe(II)-promoted rearrangement of 1,2-dioxane 565.
Scheme 165: Fe(II) cysteinate-promoted rearrangement of 1,2-dioxolane 568.
Scheme 166: The transformation of 1,2-dioxanes 572a–c under the action of FeCl2.
Scheme 167: Fe(II) cysteinate-promoted transformation of tetraoxane 574.
Scheme 168: The CoTPP-catalyzed transformation of bicyclic endoperoxides 600a–d.
Scheme 169: The CoTPP-catalyzed transformation of epoxy-1,2-dioxanes.
Scheme 170: The Ru(II)-catalyzed reactions of 1,4-endoperoxide 261g.
Scheme 171: The Ru(II)-catalyzed transformation as a key step in the synthesis of elyiapyrone A (610) from 1,4-...
Scheme 172: Peroxides with antimalarial activity.
Scheme 173: The interaction of iron ions with artemisinin (616).
Scheme 174: The interaction of FeCl2 with 1,2-dioxanes 623, 624.
Scheme 175: The mechanism of reaction 623 and 624 with Fe(II)Cl2.
Scheme 176: The reaction of bicyclic natural endoperoxides G3-factors 631–633 with FeSO4.
Scheme 177: The transformation of terpene cardamom peroxide 639.
Scheme 178: The different ways of the cleavage of tetraoxane 643.
Scheme 179: The LC–MS analysis of interaction of tetraoxane 646 with iron(II)heme 647.
Scheme 180: The rearrangement of 3,6-epidioxy-1,10-bisaboladiene (EDBD, 649).
Scheme 181: Easily oxidized substrates.
Scheme 182: Biopathway of synthesis of prostaglandins.
Scheme 183: The reduction and rearrangements of isoprostanes.
Scheme 184: The partial mechanism for linoleate 658 oxidation.
Scheme 185: The transformation of lipid hydroperoxide.
Scheme 186: The acid-catalyzed cleavage of the product from free-radical oxidation of cholesterol (667).
Scheme 187: Two pathways of catechols oxidation.
Scheme 188: Criegee-like or Hock-like rearrangement of the intermediate hydroperoxide 675 in dioxygenase enzyme...
Scheme 189: Carotinoides 679 cleavage by carotenoid cleavage dioxygenases.
Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules
- Yongsheng Chen,
- Li Wang,
- Haojie Yu,
- Zain-Ul-Abdin,
- Ruoli Sun,
- Guanghui Jing,
- Rongbai Tong and
- Zheng Deng
Beilstein J. Org. Chem. 2016, 12, 939–949, doi:10.3762/bjoc.12.92
- 400M spectrometer. The molecular weight of polymer was determined by gel permeation chromatography (GPC) (Waters-Wyatt) equipped with RI, UV, viscosity and LS detectors using tetrahydrofuran (THF) as eluent. The UV–vis spectra were recorded on a UV3802 (UNICO) ultraviolet spectrophotometer. The size
Graphical Abstract
Figure 1: (A) The synthetic routes to HBPS and HBPS-g-PDMAEMA; (B) 1H NMR spectra of HBPS and HBPS-g-PDMAEMA ...
Figure 2: (A) The transmittance of HBPS-g-PDMAEMA aqueous solution of 10 mg/mL (pH 7); (B) pictures of aqueou...
Figure 3: (A) The effect of HBPS-g-PDMAEMA concentration on the size of aggregates (pH 7); (B) photographs of...
Figure 4: The sizes of 1 mg/mL HBPE-g-PDMAEMA aggregates in aqueous solutions with different concentration of...
Figure 5: (A) Photographs of phase inversion of 1 mg/mL HBPS-g-PDMAEMA in aqueous solution with different pH ...
Figure 6: The effect of pH on: (A) the size of 1 mg/mL HBPS-g-PDMAEMA aggregates; (B) the DLS results of 1 mg...
Figure 7: (A) The UV–vis spectra of HBPS-g-PDMAEMA/pyrene solution with different polymer concentrations; (B)...
Figure 8: (A) Photographs of HBPS-g-PDMAEMA/NR in aqueous solution with different polymer concentrations; (B)...
Figure 9: (A) Plot of the concentration of NR as a function of the UV–vis absorbance at a wavelength of 520 n...
My maize and blue brick road to physical organic chemistry in materials
- Anne J. McNeil
Beilstein J. Org. Chem. 2016, 12, 229–238, doi:10.3762/bjoc.12.24
- rate in a single round-bottom flask I realized that the stir-rate effect was real. I eliminated obvious culprits, including heterogeneity and high viscosity. Puzzled, I talked about this oddity to whomever would listen and tried every experiment suggested. One day I let a reaction sit unstirred for an
Graphical Abstract
Figure 1: Summary of research experiences prior to independent career.
Figure 2: Sensing via analyte-triggered gelation.
Figure 3: Examples of structurally similar gelators and nongelators examined in our studies.
Figure 4: Relationship between dissolution enthalpies and intermolecular interactions. Gelators exhibit (on a...
Figure 5: Evolution of our design strategy for identifying new gelators.
Figure 6: New gelator scaffolds identified by predicting crystal morphologies.
Figure 7: Two complementary approaches for sensing protease activity using gel formation.
Scheme 1: Sensors based on modifying known gelator scaffolds.
Figure 8: Enjoying the outdoors with my family, especially when it involves mud! Photo credit: Donald A. McNe...
Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques
- Gabor Benkovics,
- Ondrej Hodek,
- Martina Havlikova,
- Zuzana Bosakova,
- Pavel Coufal,
- Milo Malanga,
- Eva Fenyvesi,
- Andras Darcsi,
- Szabolcs Beni and
- Jindrich Jindrich
Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11
- reached higher values due to lower viscosity of the BGE. Subsequently differences between electrophoretic mobilities with and without Cin-α-CDs in BGE decreased because of smaller size of Cin-α-CDs aggregates. The studied α-cyclodextrin derivatives offer a potential for employing them in capillary
Graphical Abstract
Figure 1: Example of elucidation of 2D NMR spectra of 2-O-Cin-α-CD.
Figure 2: 2D ROESY spectrum of 2-O-Cin-α-CD in D2O at 25 °C at 24 mM concentration.
Figure 3: Expansion of the 2D ROESY spectrum of 2-O-Cin-α-CD indicating the geometric arrangement.
Figure 4: 1H NMR spectra of 2-O-Cin-α-CD in D2O at 25 °C at different concentrations.
Figure 5: 1H NMR spectra of 3-O-Cin-α-CD in D2O at 25 °C recorded at various concentrations.
Figure 6: Diffusion coefficients of 2-O-Cin-α-CD (black) and, 3-O-Cin-α-CD (red) in D2O at various concentrat...
Figure 7: Effect of solvent on the size distribution of aggregates formed by 2-O-Cin-α-CD at 25 °C (the appli...
Figure 8: Effect of a solvent on the size distribution of aggregates formed by 3-O-Cin-α-CD at 25 °C (the app...
Figure 9: Aggregate sizes (diameter) of 2-O-Cin-α-CD (black) and 3-O-Cin-α-CD (red) in water at various tempe...
Figure 10: Schematic representation of the DLS experiment proving the host–guest nature of the aggregate forma...
Figure 11: The effect of competitive additives on the size distribution of aggregates formed by 3-O-Cin-α-CD a...
Figure 12: Expansion of the 2D ROESY spectrum of 2-O-Cin-α-CD in the presence of CioOK as competitive guest mo...
Figure 13: 1H NMR spectrum of 2-O-Cin-α-CD before (up) and after (down) the addition of CioOK in 5-fold molar ...
Figure 14: The influence of 5 mM 2-O-Cin-α-CD in BGE (right column) on the decrease of the effective electroph...
