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Search for "diastereomeric complexes" in Full Text gives 12 result(s) in Beilstein Journal of Organic Chemistry.
Reductive opening of a cyclopropane ring in the Ni(II) coordination environment: a route to functionalized dehydroalanine and cysteine derivatives
- Oleg A. Levitskiy,
- Olga I. Aglamazova,
- Yuri K. Grishin and
- Tatiana V. Magdesieva
Beilstein J. Org. Chem. 2022, 18, 1166–1176, doi:10.3762/bjoc.18.121
- spectra of 6a and 6b and spin coupling constants in the 1H NMR spectrum of 8. Characteristic correlations in the NOESY spectra of diastereomeric complexes 10 and the corresponding characteristic fragments of the spectra (full spectra are given in Supporting Information File 1); (R,S)-isomer (left) and (R
Graphical Abstract
Figure 1: Cyclic voltammograms obtained for complexes 1 (black), 2 (blue), 3 (green), 4 (red) (MeCN, 0.05 M Bu...
Scheme 1: Synthesis of complex 4.
Figure 2: Key correlations in the NOESY spectrum of complex (S)-4 and the corresponding characteristic fragme...
Scheme 2: Reductive three-membered ring-opening and follow-up chemical steps.
Figure 3: Correlations in the HMBC spectra of 6a and 6b and spin coupling constants in the 1H NMR spectrum of ...
Scheme 3: Electrochemically induced ring-opening followed by intramolecular cyclization.
Scheme 4: One-pot multistep approach to the cysteine derivatives.
Figure 4: Characteristic correlations in the NOESY spectra of diastereomeric complexes 10 and the correspondi...
Molecular recognition of N-acetyltryptophan enantiomers by β-cyclodextrin
- Spyros D. Chatziefthimiou,
- Mario Inclán,
- Petros Giastas,
- Athanasios Papakyriakou,
- Konstantina Yannakopoulou and
- Irene M. Mavridis
Beilstein J. Org. Chem. 2017, 13, 1572–1582, doi:10.3762/bjoc.13.157
- cavity, taking into account that crystal lattice forces may introduce additional and more stringent parameters for the enantiodiscrimination [9][10]. However, the crystallographic structures of diastereomeric complexes of CDs with chiral guest molecules in the literature are scarce. For β-CD with
Graphical Abstract
Scheme 1: Numbering scheme of one glucopyranose residue (G) of β-CD and the NAcTrp molecule; specific atom la...
Figure 1: 3D maps of the observed dipolar, through-space host–guest interactions depicted so as to (a) reflec...
Figure 2: Two dimers of β-CD–L-NAcTrp, stacked along the a-axis, are shown. Each β-CD dimer (A, B) encloses a...
Figure 3: β-CD–L-NAcTrp complex at the interface between two β-CD dimers along the a-axis (major orientation ...
Figure 4: “β-CD–D-NAcTrp” structure. (a) The herring bone packing of β-CD along the c-axis; (b) The guest (cy...
Figure 5: L-NAcTrp and L-NAcPhe in β-CD dimers (the lines indicate the levels of the O2 and O3 secondary hydr...
New approaches to organocatalysis based on C–H and C–X bonding for electrophilic substrate activation
- Pavel Nagorny and
- Zhankui Sun
Beilstein J. Org. Chem. 2016, 12, 2834–2848, doi:10.3762/bjoc.12.283
- containing a halogen (I···N) bond [70]. When chiral organohalides form halogen bonds with chiral acceptors, diastereomeric complexes may be formed. Thus, in 1999, Resnati reported the resolution of racemic 1,2-dibromohexafluoropropane through halogen-bonded supramolecular helices (Scheme 13) [69]. When
Graphical Abstract
Figure 1: Electrophile Activation by Hydrogen Bond Donors [1-16].
Figure 2: Early examples of C–H hydrogen bonds and their recent use in supramolecular chemistry [18,19,32-34].
Scheme 1: Design of 1,2,3-triazole-based catalysts for trityl group transfer through chloride anion binding b...
Scheme 2: Examples of chiral triazole-based catalysts for anion activation designed by Mancheno and co-worker...
Scheme 3: Application of chiral triazole-based catalysts L3 and L4 for counterion activation of pyridinium, q...
Scheme 4: Ammonium salt anion binding via C–H hydrogen bonds in solid state [40-45,50,51].
Scheme 5: Early examples of ammonium salts being used for electrophilic activation of imines in aza-Diels–Ald...
Scheme 6: Ammonium salts as hydrogen bond-donor catalysts by Bibal and co-workers [53,54].
Scheme 7: Tetraalkylammonium catalyst (L6)-catalyzed dearomatization of isoquinolinium salts [50].
Scheme 8: Tetraalkylammonium catalyst L6 complexation to halogen-containing substrates [51].
Scheme 9: Tetraalkylammonium-catalyzed aza-Diels–Alder reaction by Maruoka and co-workers [52].
Scheme 10: (A) Alkylpyridinium catalysts L13-catalyzed reaction of 1-isochroman and silyl ketene acetals by Be...
Scheme 11: Mixed N–H/C–H two hydrogen bond donors L14 and L15 as organocatalysts for ROP of lactide by Bibal a...
Scheme 12: Examples of stable complexes based on halogen bonding [68,69].
Scheme 13: Interaction between (−)-sparteine hydrobromide and (S)-1,2-dibromohexafluoropropane in the cocrysta...
Scheme 14: Iodine-catalyzed reactions that are computationally proposed to proceed through halogen bond to car...
Scheme 15: Transfer hydrogenation of phenylquinolines catalyzed by haloperfluoroalkanes by Bolm and co-workers ...
Scheme 16: Halogen bond activation of benzhydryl bromides by Huber and co-workers [82].
Scheme 17: Halogen bond-donor-catalyzed addition to oxocarbenium ions by Huber and co-workers [89].
Scheme 18: Halogen bond-donor activation of α,β-unsaturated carbonyl compounds in the [2 + 4] cycloaddition re...
Scheme 19: Halogen bond donor activation of imines in the [2 + 4] cycloaddition reaction of imine and Danishef...
Scheme 20: Transfer hydrogenation catalyzed by a chiral halogen bond donor by Tan and co-workers [91].
Scheme 21: Allylation of benzylic alcohols by Takemoto and co-workers [92].
Scheme 22: NIS induced semipinacol rearrangement via C–X bond cleavage [93].
Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization
- Barry M. Trost,
- Michael C. Ryan and
- Meera Rao
Beilstein J. Org. Chem. 2016, 12, 1136–1152, doi:10.3762/bjoc.12.110
- catalyst containing a tethered chiral sulfoxide. (c) Possible diastereomeric complexes formed from alcohol coordination. Failed sulfinate ester syntheses. Failed bicycloisomerization substrates. Reactions performed at 40 °C for 16 hours with 3 mol % of catalyst 1 in acetone at a 0.25 M concentration
Graphical Abstract
Scheme 1: Divergent behavior of the palladium and ruthenium-catalyzed Alder–ene reaction.
Scheme 2: Some asymmetric enyne cycloisomerization reactions.
Figure 1: (a) Mechanism for the redox biscycloisomerization reaction. (b) Ruthenium catalyst containing a tet...
Scheme 3: Synthesis of p-anisyl catalyst 1.
Figure 2: Failed sulfinate ester syntheses.
Scheme 4: Using norephedrine-based oxathiazolidine-2-oxide 7 for chiral sulfoxide synthesis.
Scheme 5: (a) General synthetic sequence to access enyne bicycloisomerization substrates (b) Synthesis of 2-c...
Figure 3: Failed bicycloisomerization substrates. Reactions performed at 40 °C for 16 hours with 3 mol % of c...
Scheme 6: Deprotection of [3.1.0] bicycles and X-ray crystal structure of 76.
Scheme 7: ProPhenol-catalyzed addition of zinc acetylide to acetaldehyde for the synthesis of a chiral 1,6-en...
Figure 4: Diastereomeric metal complexes formed after alcohol coordination.
Scheme 8: Curtin–Hammitt scenario of redox bicycloisomerization in acetone.
Self and directed assembly: people and molecules
- Tony D. James
Beilstein J. Org. Chem. 2016, 12, 391–405, doi:10.3762/bjoc.12.42
- diastereomeric complexes are clearly separated. The diastereomeric imine signals are particularly useful since they are in a region of the spectra clear of interference from signals due to the binol (diol) or amine. Integration of the pair of imine signals provides a diastereomeric ratio which can be related to
Graphical Abstract
Scheme 1: Reaction of trimethylsilyl cyanide with tricarbonyl (η5-cyclohexadienyl)iron(1+) salts. Reproduced ...
Figure 1: (a) Supramolecular pore formers. Reproduced with permission from [6]. Copyright 1990 Elsevier. (b) Uni...
Figure 2: An intelligent liquid crystal to read out saccharide structure as a color-change. Picture provided ...
Scheme 2: Polymeric boronic acid receptor units developed by Wulff. Reproduced from [16]. Copyright 1982 Internat...
Figure 3: Fluorescence photoinduced electron transfer (PET) pH sensor developed by A. P. De Silva.
Figure 4: Fluorescence PET sensor for saccharides.
Figure 5: (a) Glucose selective PET system. (b) Chiral discriminating PET system.
Figure 6: (a) Fluorescence photoinduced electron transfer (PET) cation sensors developed by A. P. De Silva. (...
Figure 7: (a) Pyrene diboronic acids (n = 3–8). (b) Pyrene monoboronic acid. (c) Block chart showing the rela...
Figure 8: Glysure Continuous Intravascular Glucose Monitoring (CIGM) System. Image provided by Nicholas P. Ba...
Figure 9: Chiral discrimination of D- and L-tartaric acid by (R)-8 at pH 5.6. [(R)-8] = 5.0 × 10−6 mol dm−3, ...
Figure 10: Chiral discriminating sensor (relative stereochemistry shown) constructed using a good fluorophore ...
Figure 11: Fluorescence emission intensity-pH profile of: (a) Sensor 15: 1.0 × 10−6 mol dm−3 (λex 370 nm, λem ...
Figure 12: Modular chiral discriminating d-PET systems (relative stereochemistry shown).
Figure 13: With Matthew Davidson and Steven Bull during “World Cup” lecture tour of Japan in 2002. (Left) Priv...
Figure 14: Preparation of chiral boron reagent and use as catalyst for aza-Diels–Alder reactions.
Figure 15: Chiral three component self-assembling system.
Synthesis and stereochemical assignments of diastereomeric Ni(II) complexes of glycine Schiff base with (R)-2-(N-{2-[N-alkyl-N-(1-phenylethyl)amino]acetyl}amino)benzophenone; a case of configurationally stable stereogenic nitrogen
- Hiroki Moriwaki,
- Daniel Resch,
- Hengguang Li,
- Iwao Ojima,
- Ryosuke Takeda,
- José Luis Aceña and
- Vadim A. Soloshonok
Beilstein J. Org. Chem. 2014, 10, 442–448, doi:10.3762/bjoc.10.41
- -phenylethylamine and 2-aminobenzophenone were prepared by alkylation of the nitrogen atom. Upon reaction with glycine and a Ni(II) salt, these ligands were transformed into diastereomeric complexes, as a result of the configurational stability of the stereogenic nitrogen atom. Different diastereomeric ratios were
Graphical Abstract
Figure 1: A family of chiral and achiral equivalents of nucleophilic glycine.
Scheme 1: Synthesis of chiral ligands 4a–f.
Scheme 2: Preparation of diastereomeric Ni(II) complexes 5a–f and 6a–f.
Figure 2: Crystallographic structure of (SCRN)-5b.
Figure 3: Crystallographic structure of (SCRN)-5b showing an exposure of the methyl moiety of α-phenylethylam...
Design and synthesis of quasi-diastereomeric molecules with unchanging central, regenerating axial and switchable helical chirality via cleavage and formation of Ni(II)–O and Ni(II)–N coordination bonds
- Vadim A. Soloshonok,
- José Luis Aceña,
- Hisanori Ueki and
- Jianlin Han
Beilstein J. Org. Chem. 2012, 8, 1920–1928, doi:10.3762/bjoc.8.223
- , which are able to coordinate to Ni(II) cations leading to quasi-diastereomeric complexes displaying two new elements of chirality: stereogenic axis and helix along with configurational stabilization of the stereogenic center on the nitrogen. Due to the stereocongested structural characteristics of the
- diastereomeric complexes (Ra*,Ph*,Sc*)-2 and (Ra*,Mh*,Rc*)-3, which contain at least three elements of chirality, namely stereogenic center, axis and helix (Scheme 1). The structure of these complexes incorporated two five- and one six-membered ring displaying a square-planar geometry. It is worth mentioning
- that only two out of the four possible diastereomeric complexes were accessed in a highly stereoselective manner, as a result of the intrinsic steric hindrance associated with the design of achiral ligands 1. In addition, crystallization of the diastereomeric mixtures resulted in the formation of a
Graphical Abstract
Scheme 1: Previous design of diastereomeric molecules 2 and 3 with switchable chirality starting from achiral...
Scheme 2: General design of asymmetric pentadentate ligands 4 and chiroptically switchable quasi-diastereomer...
Scheme 3: Preparation of imino–carbonyl ligands 13 by desymmetrization of achiral carbonyl–carbonyl ligands 12...
Scheme 4: Preparation of complexes 14a,b and 15 by reactions of ligands 12 with glycine.
Figure 1: Crystallographic structure of complex 14a.
Scheme 5: Oxidation of enolates 16 and formation of complexes 19 and 20.
Figure 2: Crystallographic structure of complex 19.
Enantioselective supramolecular devices in the gas phase. Resorcin[4]arene as a model system
- Caterina Fraschetti,
- Matthias C. Letzel,
- Antonello Filippi,
- Maurizio Speranza and
- Jochen Mattay
Beilstein J. Org. Chem. 2012, 8, 539–550, doi:10.3762/bjoc.8.62
- , 35501 Bielefeld, Germany 10.3762/bjoc.8.62 Abstract This review describes the state-of-art in the field of the gas-phase reactivity of diastereomeric complexes formed between a chiral artificial receptor and a biologically active molecule. The presented experimental approach is a ligand-displacement
- counterion effects. Keywords: diastereomeric complexes; gas phase enantioselectivity; kinetics; mass spectrometry; resorcin[4]arene receptor; Review Enzymes are macromolecular assemblies that make up the machinery whose structures and dynamics enable and support life functions. They are invariably
- and ρ < 1 factors in that with BS. To verify whether the measured enantioselectivity is determined by the relative stability of the starting diastereomeric complexes or by the transition states involved in the reaction path, the collision-induced dissociation spectra of the [V∙H∙tyrOMe]+ and [V∙H∙amph
Graphical Abstract
Figure 1: Examples of monoexponential decay: The slope of the line directly provides the reaction pseudo-firs...
Figure 2: Example of biexponential decay.
Figure 3: Amidoresorcin[4]arene YS.
Scheme 1: Studied (a) peptidoresorcin[4]arenes and (b) dipeptidic guests.
Figure 4: Catharanthine and vindoline, monomers constituting the anticancer vinblastine and the analogous vin...
Figure 5: Stable conformers of catharanthine.
Figure 6: Global minima of (a) [VS∙H∙T]+ and (b) [VR∙H∙T]+ complexes.
Figure 7: Guests studied in [47].
Figure 8: Selected nucleosides.
Figure 9: Example of molecular logic gate.
Figure 10: Cyclochiral resorcin[4]arenes.
Complete transfer of chirality in an intramolecular, thermal [2 + 2] cycloaddition of allene-ynes to form non-racemic spirooxindoles
- Kay M. Brummond and
- Joshua M. Osbourn
Beilstein J. Org. Chem. 2011, 7, 601–605, doi:10.3762/bjoc.7.70
- upon treatment with the chiral shift reagent. Treating racemic acetate 7 with the chiral shift reagent enabled resolution of the resulting diastereomeric complexes, which was evidenced by the resonances for the aromatic proton labeled Ha in the spectrum shown below. The spectrum of racemic acetate 7
- the racemic compound 8 as well as the enantiomerically enriched compound 8 are shown in Figure 2. In the case of the racemic compound, the resonances for the tert-butyl groups of the diastereomeric complexes are split into two distinct signals in the presence of the shift reagent; one singlet at δ
- by TLC with the exception of some baseline material. Spirooxindole 9 was purified by column chromatography and the transfer of chiral information was determined using chiral 1H NMR shift analysis. Spirooxindole 9 was treated with 0.75 equiv of (+)-Eu(hfc)3 in CDCl3. The resulting diastereomeric
Graphical Abstract
Scheme 1: Conversion of propargyl acetate 1 to spirooxindole 2 containing the core framework of welwitindolin...
Scheme 2: Preparation of enantiopure propargyl acetate 7 (R = Ac).
Figure 1: Chiral NMR shift analysis of propargyl acetate 7.
Figure 2: Chiral NMR shift analysis of allenyloxindole 8.
Scheme 3: Microwave irradiation of allenyloxindole 8.
Figure 3: Chiral NMR shift analysis of spirooxindole 9.
Figure 4: Thermally generated biradical intermediate 10.
Chiral recognition of macromolecules with cyclodextrins: pH- and thermosensitive copolymers from N-isopropylacrylamide and N-acryloyl-D/L-phenylalanine and their inclusion complexes with cyclodextrins
- Sabrina Gingter,
- Ella Bezdushna and
- Helmut Ritter
Beilstein J. Org. Chem. 2011, 7, 204–209, doi:10.3762/bjoc.7.27
- eight α-1,4 linked chiral glucopyranose units. They easily include suitable molecules with hydrophobic segments [3][4][5][6]. Due to their asymmetric centres, CDs have the ability to discriminate between suitable enantiomers. They form diastereomeric complexes with slightly different stabilities [5][6
Graphical Abstract
Scheme 1: Synthesis of copolymers 3D, 3L and CD-complexes 4D, 4L.
Figure 1: 2D NMR ROESY spectrum of monomer 2D with RAMEB-CD.
Figure 2: 2D NMR ROESY experiment showing the correlation between protons of the phenyl moiety of 4D with the...
Figure 3: NMR shifts of the complexed monomer 2D.
Figure 4: Comparison of 1H NMR spectra of 2D and 2L complexed with β-CD.
Figure 5: Complex formation with phenolphthalein and phenylalanine as competitor.
Figure 6: Hydrodynamic diameters of the copolymers and their corresponding complexes with RAMEB-CD a) L-pheny...
Molecular recognition of organic ammonium ions in solution using synthetic receptors
- Andreas Späth and
- Burkhard König
Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
Chiral trimethylsilylated C2- symmetrical diamines as phosphorous derivatizing agents for the determination of the enantiomeric excess of chiral alcohols by 1H NMR
- Anne-Sophie Chauvin and
- Alexandre Alexakis
Beilstein J. Org. Chem. 2006, 2, No. 6, doi:10.1186/1860-5397-2-6
- chiral compounds, based on the formation of diastereomeric complexes or derivatives [1]. Among these methods, 31P is a very attractive nucleus to be used for NMR analysis because of the large chemical dispersion and the simplicity of the spectra [2]. Some of the chiral phosphorous chemical derivatisation
Graphical Abstract
Scheme 1: C2-diamines used in this study.
Scheme 2: Synthesis of diamines 1 and 2.
Scheme 3: Synthesis of diamine 3.
Figure 1: 1H NMR spectrum in the -0.4↔0.6 ppm region of 2-(2-isopropyl-5-methyl-cyclohexyloxy)-1,3-bis-trimet...
