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Search for "Glaser coupling" in Full Text gives 18 result(s) in Beilstein Journal of Organic Chemistry.
Active-metal template clipping synthesis of novel [2]rotaxanes
- Cătălin C. Anghel,
- Teodor A. Cucuiet,
- Niculina D. Hădade and
- Ion Grosu
Beilstein J. Org. Chem. 2023, 19, 1776–1784, doi:10.3762/bjoc.19.130
- the reaction used to complete rotaxane synthesis, hence the name “active template”. This strategy was first applied by Saito and co-workers [35], using a Cu(I) template to catalyze a Glaser coupling reaction. The method has been extended for other reactions, for example Ni-catalyzed homocoupling of
Graphical Abstract
Figure 1: a. Active-metal template (reported in the literature) and b. active-metal template clipping (used i...
Figure 2: Macrocyclic components of the [2]rotaxanes.
Scheme 1: Synthesis of the key intermediates 6 and 8 and of the reference macrocycle M1.
Scheme 2: Synthesis of [2]rotaxanes R1 and R2.
Figure 3: Top: HRESI(+)-MS spectrum of the rotaxane R1 (left) and R2 (right) [experimental (top) and calculat...
1,2,3-Triazoles as leaving groups in SNAr–Arbuzov reactions: synthesis of C6-phosphonated purine derivatives
- Kārlis-Ēriks Kriķis,
- Irina Novosjolova,
- Anatoly Mishnev and
- Māris Turks
Beilstein J. Org. Chem. 2021, 17, 193–202, doi:10.3762/bjoc.17.19
- solutions, as used in the Cu(II) and ascorbate protocol. In some cases, the use of Et3N lowered the yield of 2,6-bistriazolylpurines 6c and 6f–i due to the competing Glaser coupling [38][39] and the reduction of 2,6-diazide 5 by the Cu(I) species [40][41]. The bistriazolyl derivatives 6a–i were easily
Graphical Abstract
Scheme 1: Structural diversity and synthetic methods of purinylphosphonates. MWI = microwave irradiation; LG ...
Scheme 2: Synthetic routes for the formation of purinylphosphonates 4.
Scheme 3: Synthesis of phosphonates 2, 7, and 8.
Scheme 4: Synthesis of phosphonic acid monoesters 3 and 7–9 as well as phosphonic acid 10.
Figure 1: Screenings of the rate for the ester group cleavage (conversion determined by NMR spectroscopy) in ...
Scheme 5: Synthesis of 2,6-bistriazolylpurine derivatives 6a–i.
Scheme 6: SNAr–Arbuzov reaction between the bistriazolylpurines 6a–i and P(OEt)3.
Figure 2: Single-crystal X-ray analysis of diethyl (9-heptyl-2-(4-phenyl-1H-1,2,3-triazol-1-yl)-9H-purin-6-yl...
Synthetic approaches to bowl-shaped π-conjugated sumanene and its congeners
- Shakeel Alvi and
- Rashid Ali
Beilstein J. Org. Chem. 2020, 16, 2212–2259, doi:10.3762/bjoc.16.186
- connected asymmetric bowls, as well as atropisomerism, was constructed by Hirao and his two group members, namely Amaya and Kobayashi, starting from the same bromo derivative 82. First it was converted into ethynylsumanene 91 using a Sonogashira-coupling which on subsequent desilylation and Glaser-coupling
Graphical Abstract
Figure 1: Representation of corannulene (1) and sumanene (2), the subunits of fullerene (C60).
Scheme 1: Mehta’s unsuccessful effort for the synthesis of sumanene scaffold 2.
Scheme 2: First synthesis of sumanene 2 by Sakurai et al. from norbornadiene 10.
Scheme 3: Synthesis of trimethylsumanene 28 from easily accessible norbornadiene (10).
Scheme 4: Generation of anions 29–31 and the preparation of tris(trimethylsilyl)sumanene 32.
Scheme 5: Synthesis of tri- and hexa-substituted sumanene derivatives.
Scheme 6: Synthesis of bowl-shaped π-extended sumanene derivatives 37a–f.
Scheme 7: Synthesis of monooxasumanene 38, trioxosumanene 40 along with imination of them.
Scheme 8: Synthesis of trimethylsumanenetrione 46 and exo-functionalized products 45a,b.
Scheme 9: Synthesis of bisumanenylidene 47 and sumanene dimer 48 from 2.
Scheme 10: The mono-substitution of 2 to generate diverse mono-sumanene derivatives 49a–d.
Scheme 11: Synthesis of sumanene building block 53 useful for further extension.
Scheme 12: Synthesis of hexafluorosumanene derivative 55 by Sakurai and co-workers.
Scheme 13: Preparation of sumanene-based carbene 60 and its reaction with cyclohexane.
Scheme 14: Barton–Kellogg reaction for the synthesis of sterically hindered alkenes.
Scheme 15: Synthesis of hydroxysumanene 68 by employing Baeyer–Villiger oxidation.
Scheme 16: Synthesis of sumanene derivatives having functionality at an internal carbon.
Scheme 17: Mechanism for nucleophilic substitution reaction at the internal carbon.
Scheme 18: Synthesis of diverse monosubstituted sumanene derivatives.
Scheme 19: Synthesis of di- and trisubstituted sumanene derivatives from sumanene (2).
Scheme 20: Preparation of monochlorosumanene 88 and hydrogenation of sumanene (2).
Scheme 21: The dimer 90 and bissumanenyl 92 achieved from halosumannes.
Scheme 22: Pyrenylsumanene 93 involving the Suzuki-coupling as a key transformation.
Scheme 23: Synthesis of various hexaarylsumanene derivatives using the Suzuki-coupling reaction.
Scheme 24: Synthesis of hexasubstituted sumanene derivatives 96 and 97.
Scheme 25: Synthesis of thioalkylsumanenes via an aromatic nucleophilic substitution reaction.
Scheme 26: Synthesis of tris(ethoxycarbonylethenyl)sumanene derivative 108.
Scheme 27: Synthesis of ferrocenyl-based sumanene derivatives.
Scheme 28: Synthesis of sumanenylferrocene architectures 118 and 119 via Negishi coupling.
Scheme 29: Diosmylation and the synthesis of phenylboronate ester 121 of sumanene.
Scheme 30: Synthesis of the iron-complex of sumanene.
Scheme 31: Synthesis of tri- and mononuclear sumanenyl zirconocene complexes.
Scheme 32: Synthesis of [CpRu(η6-sumanene)]PF6.
Scheme 33: Preparation of sumanene-based porous coordination networks 127 (spherical tetramer units) and 128 (...
Scheme 34: Synthesis of sumanenylhafnocene complexes 129 and 130.
Scheme 35: Synthesis of 134 and 135 along with PdII coordination complex 136.
Scheme 36: Synthesis of alkali metals sumanene complex K7(C21H102−)2(C21H93−)·8THF (137) containing di- and tr...
Scheme 37: The encapsulation of a Cs+ ion between two sumanenyl anions.
Scheme 38: Synthesis of monothiasumanene 140 and dithiasumanene 141 from 139.
Scheme 39: Synthesis of trithiasumanene 151 by Otsubo and his co-workers.
Scheme 40: Synthesis of trithiasumanene derivatives 155 and 156.
Scheme 41: Synthetic route towards hexathiolated trithiasumanenes 158.
Scheme 42: Synthesis of triselenasumanene 160 by Shao and teammates.
Scheme 43: Synthesis of tritellurasumanene derivatives from triphenylene skeletons.
Scheme 44: Synthesis of pyrazine-fused sumanene architectures through condensation reaction.
Scheme 45: Treatment of the trichalcogenasumanenes with diverse oxidative reagents.
Scheme 46: Ring-opening reaction with H2O2 and oxone of heterasumanenes 178 and 179.
Scheme 47: Synthesis of polycyclic compounds from sumanene derivatives.
Scheme 48: Synthesis of diimide-based heterocycles reported by Shao’s and co-workers.
Scheme 49: Synthesis of pristine trichalcogenasumanenes, 151, 205, and 206.
Scheme 50: Synthesis of trichalcogenasumanenes via hexaiodotriphenylene precursor 208.
Scheme 51: Synthesis of trisilasumanenes 214 and 215.
Scheme 52: Synthesis of trisilasumanene derivatives 218 and 219.
Scheme 53: Synthesis of novel trigermasumanene derivative 223.
Scheme 54: An attempt towards the synthesis of tristannasumanene derivative 228.
Scheme 55: Synthesis of triphosphasumanene trisulfide 232 from commercially available 229.
Scheme 56: The doping of sumanene derivatives with chalcogens (S, Se, Te) and phosphorus.
Scheme 57: Synthesis of heterasumanene containing three different heteroatoms.
Scheme 58: Synthesis of trichalcogenasumanene derivatives 240 and 179.
Scheme 59: Preparation of trichalcogenasumanenes 245 and 248.
Scheme 60: Design and synthesis of trichalcogenasumanene derivatives 252 and 178.
Scheme 61: Synthesis of spirosumanenes 264–269 and non-spiroheterasumanenes 258–263.
Scheme 62: Synthesis of sumanene-type hetero polycyclic compounds.
Scheme 63: Synthesis of triazasumanenes 288 and its sulfone congener 287.
Scheme 64: Synthesis of C3-symmetric chiral triaryltriazasumanenes via cross-coupling reaction.
Scheme 65: Synthesis of mononaphthosumanene 293 using Suzuki coupling as a key step.
Scheme 66: Synthesis of di- and trinaphthosumanene derivatives 302–304.
Scheme 67: Synthesis of hemifullerene skeletons by Hirao’s group.
Scheme 68: Design and construction of C70 fragment from a C60 sumanene fragment.
Towards triptycene functionalization and triptycene-linked porphyrin arrays
- Gemma M. Locke,
- Keith J. Flanagan and
- Mathias O. Senge
Beilstein J. Org. Chem. 2020, 16, 763–777, doi:10.3762/bjoc.16.70
- with porphyrin 8 [40], resulting in a yield of 50% of the purple-green product 9. An additional reaction was carried out via a Glaser coupling with BODIPY 10 in order to extend the distance between the two BODIPY chromophores but the desired product 11 could not be detected by spectroscopic techniques
Graphical Abstract
Figure 1: Triptycene as a scaffold and selected porphyrin and BODIPY arrays.
Scheme 1: Sonogashira cross-coupling reactions to form symmetric porphyrin and BODIPY triptycene-linked dyads....
Scheme 2: Sonogashira cross-coupling reactions to form a triptycene-substituted porphyrin monomer and an unsy...
Scheme 3: Synthesis of the triptycene-porphyrin-triptycene complex 18.
Figure 2: Single crystal X-ray structure of triptycene 5. (a) Molecular structure of 5 in the crystal with hy...
Figure 3: Single crystal X-ray structure of triptycene-linked zinc-nickel porphyrin dimer 16 showing the conf...
Figure 4: Views of the single crystal X-ray structure of triptycene-linked zinc-nickel porphyrin dimer 16 sho...
Figure 5: Expanded structure view of the triptycene-linked zinc-nickel porphyrin dimer 16 showing the repeati...
Figure 6: UV–vis of symmetric and unsymmetric triptycene porphyrin dimers 9 and 16, and the triptycene porphy...
Figure 7: Emission spectrum of symmetric and unsymmetric triptycene-linked porphyrin dimers 9 and 16, and a t...
Figure 8: Compounds used for spectroscopic comparisons.
Figure 9: UV–vis spectra of various porphyrin/BODIPY dimers with different linker groups in CHCl3.
Figure 10: Fluorescence emission spectrum of various porphyrin/BODIPY dimers with different linker groups in C...
Regioselectively α- and β-alkynylated BODIPY dyes via gold(I)-catalyzed direct C–H functionalization and their photophysical properties
- Takahide Shimada,
- Shigeki Mori,
- Masatoshi Ishida and
- Hiroyuki Furuta
Beilstein J. Org. Chem. 2020, 16, 587–595, doi:10.3762/bjoc.16.53
- Glaser-coupling reactions [37]. Conventionally, an alkynylation of the BODIPY core has been achieved by palladium-catalyzed Sonogashira cross-coupling with halogenated BODIPYs (Figure 1b) [35][37]. However, due to the coexistence of multiple C–H bonds, a regioselective direct C–H alkynylation of the
Graphical Abstract
Figure 1: (a) Chemical structures of BODIPY (1) and dipyrromethane (2). (b) C–C bond forming alkynylations of...
Scheme 1: Synthesis of α-ethynyl-substituted BODIPY derivatives 3a and 4a.
Scheme 2: Synthesis of β-ethynyl-substituted BODIPY derivatives 5a and 5b and β,β'-diethynyl-substituted comp...
Figure 2: Top and front views of the crystal structures of (a) 4a and (b) 6b with 50% thermal ellipsoid proba...
Figure 3: Partial 1H NMR spectra of (a) 1a, (b) 3a, (c) 4a, (d) 5a, and (e) 6a recorded in CDCl3 at 298 K. As...
Figure 4: UV–vis absorption spectra of the BODIPY derivatives, (a) 1a (green), 3a (blue), 4a (red), and (b) 1a...
Figure 5: Fluorescence spectra of BODIPY derivatives. (a) 1a (green), 3a (blue), 4a (red) and (b) 1a (green), ...
Nanopatterns of arylene–alkynylene squares on graphite: self-sorting and intercalation
- Tristan J. Keller,
- Joshua Bahr,
- Kristin Gratzfeld,
- Nina Schönfelder,
- Marcin A. Majewski,
- Marcin Stępień,
- Sigurd Höger and
- Stefan-S. Jester
Beilstein J. Org. Chem. 2019, 15, 1848–1855, doi:10.3762/bjoc.15.180
- other sides of the square is based on the Glaser coupling of acetylene-terminated precursor structures. These side chains give macrocycles with reduced symmetry. They cannot be obtained by the cyclization of small building blocks, but require the stepwise formation of more complex precursors, where the
Graphical Abstract
Figure 1: Chemical structures of the molecular squares 1a/b, the kekulene derivative 2, and octulene derivati...
Figure 2: (a)–(c) Scanning tunneling microscopy images, (d)–(f) supramolecular models, and (g)–(l) schematic ...
Figure 3: (a) Overview scanning tunneling microscopy image of a nanopattern of 1a with intermolecularly inter...
Figure 4: (a–c) Scanning tunneling microscopy images of a nanopattern of 1a with intermolecularly intercalate...
Interactions between shape-persistent macromolecules as probed by AFM
- Johanna Blass,
- Jessica Brunke,
- Franziska Emmerich,
- Cédric Przybylski,
- Vasil M. Garamus,
- Artem Feoktystov,
- Roland Bennewitz,
- Gerhard Wenz and
- Marcel Albrecht
Beilstein J. Org. Chem. 2017, 13, 938–951, doi:10.3762/bjoc.13.95
- end groups were prepared starting from diacetylene-modified cyclodextrin monomers by a combined Glaser coupling/click chemistry approach. Structural perfection of the neutral CD polymers and inclusion complex formation with ditopic and monotopic guest molecules were proven by MALDI–TOF and UV–vis
- phenyl moieties and β-CD rings leading to daisy chains [54]. The polymerization of 7 was performed through Glaser coupling in pyridine catalyzed by Cu(I)/Cu(II). After removal of low molecular weight material by ultrafiltration polymer 8 was isolated as a light orange solid in 91% yield. Polyrotaxane
- than one polymer molecule might be involved. Conclusion In conclusion, regular water-soluble shape-persistent CD polymers based on poly(phenylene butadiynylene) were prepared by a straightforward Glaser coupling/click chemistry approach, which can be attached to planar silicon surfaces as well as AFM
Graphical Abstract
Figure 1: Interaction of a shape-persistent CD polymer with ditopic guests.
Figure 2: Schematic representation of tip and surface modifications realized in this study (bottom). Blue lin...
Scheme 1: Synthesis of the CD polymer. a) conc. HNO3, reflux, 6 d; b) tert-butanol, cat. H2SO4, MgSO4, CH2Cl2...
Figure 3: Absorption spectra of monomer 7 (solid red line) and polymer 8 (solid blue line) in water. Emission...
Figure 4: Positive linear MALDI–TOF spectrum of polymer 8 using HABA/TMG2 matrix.
Figure 5: SANS data for polymer 8 and fit by cylindrical model (solid line).
Scheme 2: Ditopic and monotopic guest molecules.
Figure 6: Solubility of polymer 8 in the presence of ditopic connector 9 (black graph) and 1-aminoadamantane ...
Scheme 3: Synthesis of amino functionalized polymer 12.
Figure 7: Characteristic force curves recorded during retraction of the AFM tip from the surface. Four functi...
Figure 8: Graphical summary of experimental results for the four configurations of CD attachment introduced i...
Figure 9: (a) Detail of the end of a force curve for a polymer-functionalized tip retracted from a polymer-fu...
Figure 10: Characteristic result of a friction experiment for a polymer-functionalized tip sliding on a surfac...
Effect of the ortho-hydroxy group of salicylaldehyde in the A3 coupling reaction: A metal-catalyst-free synthesis of propargylamine
- Sujit Ghosh,
- Kinkar Biswas,
- Suchandra Bhattacharya,
- Pranab Ghosh and
- Basudeb Basu
Beilstein J. Org. Chem. 2017, 13, 552–557, doi:10.3762/bjoc.13.53
- possibility for the Glaser coupling of the terminal alkyne as the byproduct [37]. Interestingly, hitherto there is no report for the A3 coupling reaction in the absence of a metal catalyst except of one example in a three-component reaction using an alkynylcarboxylic acid instead of a terminal alkyne [38]. In
- are straightforward and products are obtained in good to excellent yields. The metal-free approach also offers the advantages of avoiding any possible byproduct arising out from the Glaser coupling of terminal alkynes as well as contamination with metal species. The present protocol supersedes the
Graphical Abstract
Scheme 1: Representative examples of bioactive compounds bearing a propargylamine moiety and synthesis of var...
Scheme 2: Various metal-catalyzed methods for the synthesis of propargylamine.
Figure 1: Synthesis of various propargylamines from various salicylaldehydes under metal-catalyst-free condit...
Scheme 3: Plausible mechanism for the metal-free A3 coupling from salicylaldehyde.
Selected synthetic strategies to cyclophanes
- Sambasivarao Kotha,
- Mukesh E. Shirbhate and
- Gopalkrushna T. Waghule
Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142
Graphical Abstract
Figure 1: General representation of cyclophanes.
Figure 2: cyclophanes one or more with heteroatom.
Figure 3: Metathesis catalysts 12–17 and C–C coupling catalyst 18.
Figure 4: Natural products containing the cyclophane skeleton.
Figure 5: Turriane family of natural products.
Scheme 1: Synthesis of [3]ferrocenophanes through Mannich reaction. Reagents and conditions: (i) excess HNMe2...
Scheme 2: Synthesis of cyclophanes through Michael addition. Reagents and conditions: (i) xylylene dibromide,...
Scheme 3: Synthesis of normuscopyridine analogue 37 through an oxymercuration–oxidation strategy. Reagents an...
Scheme 4: Synthesis of tribenzocyclotriyne 39 through Castro–Stephens coupling reaction. Reagents and conditi...
Scheme 5: Synthesis of cyclophane 43 through Glaser–Eglinton coupling. Reagents and conditions: (i) 9,10-bis(...
Scheme 6: Synthesis of the macrocyclic C-glycosyl cyclophane through Glaser coupling. Reagents and conditions...
Scheme 7: Synthesis of cyclophane-containing complex 49 through Glaser–Eglinton coupling reaction. Reagents a...
Scheme 8: Synthesis of cyclophane 53 through Glaser–Eglinton coupling. Reagents and conditions: (i) K2CO3, ac...
Figure 6: Cyclophanes 54–56 that have been synthesized through Glaser–Eglinton coupling.
Figure 7: Synthesis of tetrasubstituted [2.2]paracyclophane 57 and chiral cyclophyne 58 through Eglinton coup...
Scheme 9: Synthesis of cyclophane through Glaser–Hay coupling reaction. Reagents and conditions: (i) CuCl2 (1...
Scheme 10: Synthesis of seco-C/D ring analogs of ergot alkaloids through intramolecular Heck reaction. Reagent...
Scheme 11: Synthesis of muscopyridine 73 via Kumada coupling. Reagents and conditions: (i) 72, THF, ether, 20 ...
Scheme 12: Synthesis of the cyclophane 79 via McMurry coupling. Reagents and conditions: (i) 75, decaline, ref...
Scheme 13: Synthesis of stilbenophane 81 via McMurry coupling. Reagents and conditions: (i) TiCl4, Zn, pyridin...
Scheme 14: Synthesis of stilbenophane 85 via McMurry coupling. Reagents and conditions: (i) NBS (2 equiv), ben...
Figure 8: List of cyclophanes prepared via McMurry coupling reaction as a key step.
Scheme 15: Synthesis of paracyclophane by cross coupling involving Pd(0) catalyst. Reagents and conditions: (i...
Scheme 16: Synthesis of the cyclophane 112 via the pinacol coupling and 113 by RCM. Reagents and conditions: (...
Scheme 17: Synthesis of cyclophane derivatives 122a–c via Sonogoshira coupling. Reagents and conditions: (i) C...
Scheme 18: Synthesis of cyclophane 130 via Suzuki–Miyaura reaction as a key step. Reagents and conditions: (i)...
Scheme 19: Synthesis of the mycocyclosin via Suzuki–Miyaura cross coupling. Reagents and conditions: (i) benzy...
Scheme 20: Synthesis of cyclophanes via Wurtz coupling reaction Reagents and conditions: (i) PhLi, Et2O, C6H6,...
Scheme 21: Synthesis of non-natural glycophanes using alkyne metathesis. Reagents and conditions: (i) G-I (12)...
Figure 9: Synthesis of cyclophanes via ring-closing alkyne metathesis.
Scheme 22: Synthesis of crownophanes by cross-enyne metathesis. Reagents and conditions: (i) G-II (13), 5 mol ...
Scheme 23: Synthesis of (−)-cylindrocyclophanes A (156) and (−)-cylindrocyclophanes F (155). Reagents and cond...
Scheme 24: Synthesis of cyclophane 159 derivatives via SM cross-coupling and RCM. Reagents and conditions: (i)...
Scheme 25: Sexithiophene synthesis via cross metathesis. Reagents and conditions: (i) 161, Pd(PPh3)4, K2CO3, T...
Scheme 26: Synthesis of pyrrole-based cyclophane using enyne metathesis. Reagents and conditions: (i) Se, chlo...
Scheme 27: Synthesis of macrocyclic derivatives by RCM. Reagents and conditions: (i) G-I/G-II, CH2Cl2, 0.005 M...
Scheme 28: Synthesis of enantiopure β-lactam-based dienyl bis(dihydrofuran) 179. Reagents and conditions: (i) ...
Scheme 29: Synthesis of a [1.1.6]metaparacyclophane derivative 183 via SM cross coupling. Reagents and conditi...
Scheme 30: Synthesis of a [1.1.6]metaparacyclophane derivative 190 via SM cross coupling. Reagents and conditi...
Scheme 31: Template-promoted synthesis of cyclophanes involving RCM. Reagents and conditions: (i) acenaphthene...
Scheme 32: Synthesis of [3.4]cyclophane derivatives 200 via SM cross coupling and RCM. Reagents and conditions...
Figure 10: Examples for cyclophanes synthesized by RCM.
Scheme 33: Synthesis of the longithorone C framework assisted by fluorinated auxiliaries. Reagents and conditi...
Scheme 34: Synthesis of the longithorone framework via RCM. Reagents and conditions: (i) 213, NaH, THF, rt, 10...
Scheme 35: Synthesis of floresolide B via RCM as a key step. Reagents and conditions: (i) G-II (13, 0.1 equiv)...
Scheme 36: Synthesis of normuscopyridine (223) by the RCM strategy. Reagents and condition: (i) Mg, THF, hexen...
Scheme 37: Synthesis of muscopyridine (73) via RCM. Reagents and conditions: (i) 225, NaH, THF, 0 °C to rt, 1....
Scheme 38: Synthesis of muscopyridine (73) via RCM strategy. Reagents and conditions: (i) NaH, n-BuLi, 5-bromo...
Scheme 39: Synthesis of pyridinophane derivatives 223 and 245. Reagents and conditions: (i) PhSO2Na, TBAB, CH3...
Scheme 40: Synthesis of metacyclophane derivatives 251 and 253. Reagents and conditions: (i) 240, NaH, THF, rt...
Scheme 41: Synthesis of normuscopyridine and its higher analogues. Reagents and conditions: (i) alkenyl bromid...
Scheme 42: Synthesis of fluorinated ferrocenophane 263 via a [2 + 2] cycloaddition. Reagents and conditions: (...
Scheme 43: Synthesis of [2.n]metacyclophanes 270 via a [2 + 2] cycloaddition. Reagents and conditions: (i) Ac2...
Scheme 44: Synthesis of metacyclophane 273 by a [2 + 2 + 2] co-trimerization. Reagents and conditions: (i) [Rh...
Scheme 45: Synthesis of paracyclophane 276 via a [2 + 2 + 2] cycloaddition reaction. Reagents and conditions: ...
Scheme 46: Synthesis of cyclophane 278 via a [2 + 2 + 2] cycloaddition reaction. Reagents and conditions: (i) ...
Scheme 47: Synthesis of cyclophane 280 via a [2 + 2 + 2] cycloaddition. Reagents and conditions: (i) [(Rh(cod)(...
Scheme 48: Synthesis of taxane framework by a [2 + 2 + 2] cycloaddition. Reagents and conditions: (i) Cp(CO)2 ...
Scheme 49: Synthesis of cyclophane 284 and 285 via a [2 + 2 + 2] cycloaddition reaction. Reagents and conditio...
Scheme 50: Synthesis of pyridinophanes 293a,b and 294a,b via a [2 + 2 + 2] cycloaddition. Reagents and conditi...
Scheme 51: Synthesis of pyridinophanes 296 and 297 via a [2 + 2 + 2] cycloaddition. Reagents and conditions: (...
Scheme 52: Synthesis of triazolophane by a 1,3-dipolar cycloaddition. Reagents and conditions: (i) propargyl b...
Scheme 53: Synthesis of glycotriazolophane 309 by a click reaction. Reagents and conditions: (i) LiOH, H2O, Me...
Figure 11: Cyclophanes 310 and 311 prepared via click chemistry.
Scheme 54: Synthesis of cyclophane via the Dötz benzannulation. Reagents and conditions: (i) THF, 100 °C, 12 h...
Scheme 55: Synthesis of [6,6]metacyclophane by a Dötz benzannulation. Reagents and conditions: (i) THF, 100 °C...
Scheme 56: Synthesis of cyclophanes by a Dötz benzannulation. Reagents and conditions: (i) THF, 65 °C, 3 h; (i...
Scheme 57: Synthesis of muscopyridine (73) via an intramolecular DA reaction of ketene. Reagents and condition...
Scheme 58: Synthesis of bis[10]paracyclophane 336 via Diels–Alder reaction. Reagents and conditions: (i) DMAD,...
Scheme 59: Synthesis of [8]paracyclophane via DA reaction. Reagents and conditions: (i) maleic anhydride, 3–5 ...
Scheme 60: Biomimetic synthesis of (−)-longithorone A. Reagents and conditions: (i) Me2AlCl, CH2Cl2, −20 °C, 7...
Scheme 61: Synthesis of sporolide B (349) via a [4 + 2] cycloaddition reaction. Reagents and conditions: (i) P...
Scheme 62: Synthesis of the framework of (+)-cavicularin (352) via a [4 + 2] cycloaddition. Reagents and condi...
Scheme 63: Synthesis of oxazole-containing cyclophane 354 via Beckmann rearrangement. Reagents and conditions:...
Scheme 64: Synthesis of cyclophanes 360a–c via benzidine rearrangement. Reagents and conditions: (i) 356a–d, K2...
Scheme 65: Synthesis of cyclophanes 365a–c via benzidine rearrangement. Reagents and conditions: (i) BocNHNH2,...
Scheme 66: Synthesis of metacyclophane 367 via Ciamician–Dennstedt rearrangement. Reagents and conditions: (i)...
Scheme 67: Synthesis of cyclophane by tandem Claisen rearrangement and RCM as key steps. Reagents and conditio...
Scheme 68: Synthesis of cyclophane derivative 380. Reagents and conditions: (i) K2CO3, CH3CN, allyl bromide, r...
Scheme 69: Synthesis of metacyclophane via Cope rearrangement. Reagents and conditions: (i) MeOH, NaBH4, rt, 1...
Scheme 70: Synthesis of cyclopropanophane via Favorskii rearrangement. Reagents and conditions: (i) Br2, CH2Cl2...
Scheme 71: Cyclophane 389 synthesis via photo-Fries rearrangement. Reagents and conditions: (i) DMAP, EDCl/CHCl...
Scheme 72: Synthesis of normuscopyridine (223) via Schmidt rearrangement. Reagents and conditions: (i) ethyl s...
Scheme 73: Synthesis of crownophanes by tandem Claisen rearrangement. Reagents and conditions: (i) diamine, Et3...
Scheme 74: Attempted synthesis of cyclophanes via tandem Claisen rearrangement and RCM. Reagents and condition...
Scheme 75: Synthesis of muscopyridine via alkylation with 2,6-dimethylpyridine anion. Reagents and conditions:...
Scheme 76: Synthesis of cyclophane via Friedel–Craft acylation. Reagents and conditions: (i) CS2, AlCl3, 7 d, ...
Scheme 77: Pyridinophane 418 synthesis via Friedel–Craft acylation. Reagents and conditions: (i) 416, AlCl3, CH...
Scheme 78: Cyclophane synthesis involving the Kotha–Schölkopf reagent 421. Reagents and conditions: (i) NBS, A...
Scheme 79: Cyclophane synthesis involving the Kotha–Schölkopf reagent 421. Reagents and conditions: (i) BEMP, ...
Scheme 80: Cyclophane synthesis by coupling with TosMIC. Reagents and conditions: (i) (a) ClCH2OCH3, TiCl4, CS2...
Scheme 81: Synthesis of diaza[32]cyclophanes and triaza[33]cyclophanes. Reagents and conditions: (i) DMF, NaH,...
Scheme 82: Synthesis of cyclophane 439 via acyloin condensation. Reagents and conditions: (i) Na, xylene, 75%;...
Scheme 83: Synthesis of multibridged binuclear cyclophane 442 by aldol condensation. Reagents and conditions: ...
Scheme 84: Synthesis of various macrolactones. Reagents and conditions: (i) iPr2EtN, DMF, 77–83%; (ii) TBDMSCl...
Scheme 85: Synthesis of muscone and muscopyridine via Yamaguchi esterification. Reagents and conditions: (i) 4...
Scheme 86: Synthesis of [5]metacyclophane via a double elimination reaction. Reagents and conditions: (i) LiBr...
Figure 12: Cyclophanes 466–472 synthesized via Hofmann elimination.
Scheme 87: Synthesis of cryptophane via Baylis–Hillman reaction. Reagents and conditions: (i) methyl acrylate,...
Scheme 88: Synthesis of cyclophane 479 via double Chichibabin reaction. Reagents and conditions: (i) excess 478...
Scheme 89: Synthesis of cyclophane 483 via double Chichibabin reaction. Reagents and conditions: (i) 481, OH−;...
Scheme 90: Synthesis of cyclopeptide via an intramolecular SNAr reaction. Reagents and conditions: (i) TBAF, T...
Scheme 91: Synthesis of muscopyridine (73) via C-zip ring enlargement reaction. Reagents and conditions: (i) H...
Figure 13: Mechanism of the formation of compound 494.
Scheme 92: Synthesis of indolophanetetraynes 501a,b using the Nicholas reaction as a key step. Reagents and co...
Scheme 93: Synthesis of cyclophane via radical cyclization. Reagents and conditions: (i) cyclododecanone, phen...
Scheme 94: Synthesis of (−)-cylindrocyclophanes A (156) and (−)-cylindrocyclophanes F (155). Reagents and cond...
Scheme 95: Cyclophane synthesis via Wittig reaction. Reagents and conditions: (i) LiOEt (2.1 equiv), THF, −78 ...
Figure 14: Representative examples of cyclophanes synthesized via Wittig reaction.
Scheme 96: Synthesis of the [6]paracyclophane via isomerization of Dewar benzene. Reagents and conditions: (i)...
Synthesis of antibacterial 1,3-diyne-linked peptoids from an Ugi-4CR/Glaser coupling approach
- Martin C. N. Brauer,
- Ricardo A. W. Neves Filho,
- Bernhard Westermann,
- Ramona Heinke and
- Ludger A. Wessjohann
Beilstein J. Org. Chem. 2015, 11, 25–30, doi:10.3762/bjoc.11.4
- linking reactions like, e.g., click reactions or amide bonds, the Glaser coupling allows the use of truly identical monomers. This decreases the number of steps for appropriate starting materials, and allows access to true homodimers in sensu strictu. Results and Discussion To achieve the synthesis of
- monomers eligible for dimerizations by Glaser coupling, equimolar amounts of propargylamine (3), aldehyde 4, carboxylic acid 5, and isocyanides 6 were reacted in methanol at room temperature over 24 h following well established Ugi protocols [12]. After flash column chromatography N-propargyl peptoids 7a–j
- . In addition, HPLC analyses revealed that an adjacent stereocenter (Table 1, entry 8, 7h/8h) does not racemize under the reaction conditions of both the MCR and the Glaser coupling. Due to the high selectivity and high conversions found in the Glaser coupling step, our attention turned toward the
Graphical Abstract
Figure 1: Apoptosis inducer C2-symmetric 1,3-diyne-linked peptide 1 and its inactive monomer 2.
Scheme 1: Combinatorial Glaser coupling involving acetylenes 7f, 7j and 7h.
Figure 2: Expanded region of the ESI-MS spectrum (positive mode) and the HPLC chromatogram of the crude mixed...
Figure 3: Growth inhibition of Bacillus subtilis by compounds 8a–j at 1 µM (15 h), and standard erythromycin ...
Building complex carbon skeletons with ethynyl[2.2]paracyclophanes
- Ina Dix,
- Lidija Bondarenko,
- Peter G. Jones,
- Thomas Oeser and
- Henning Hopf
Beilstein J. Org. Chem. 2014, 10, 2013–2020, doi:10.3762/bjoc.10.209
- , highly unsaturated carbon frameworks. Thus both the pseudo-geminal- 2 and the pseudo-ortho-diethynylcyclophane 4 can be dimerized by Glaser coupling to the respective dimers 9/10 and 11/12. Whereas the former isomer pair could not be separated so far, the latter provided the pure diastereomers after
- their usual spectroscopic and analytical data, the new cyclophanes 11, 12, 19, 20, 22, and 26 were characterized by X-ray structural analysis. Keywords: carbon-rich molecules; complex carbon scaffolds; cyclophanes; Glaser coupling; multibridged cyclophanes; X-ray analysis; Introduction Several years
- - (1), 1,3- (3), and 1,4-diethynylbenzene (5) (Scheme 1). These simple, flat molecules have been used extensively for the deliberate construction of larger polyaromatic hydrocarbons employing classical (e.g., Glaser coupling and its variants) or modern acetylenic coupling reactions (e.g., the
Graphical Abstract
Scheme 1: Planar and layered ethynyl aromatics as building blocks for extended aromatic structures.
Scheme 2: Previous coupling experiments with pseudo-ortho-diethynyl[2.2]paracyclophane 4.
Scheme 3: Glaser coupling of pseudo-gem-diethynyl[2.2]paracyclophane 2.
Scheme 4: Glaser coupling of pseudo-ortho-diethynyl[2.2]paracyclophane, 4.
Figure 1: Above: The molecule of compound 11 in the crystal; ellipsoids represent 30% probability levels. Onl...
Figure 2: Above: The molecule of compound 12 in the crystal; ellipsoids represent 50% probability levels. Onl...
Scheme 5: Sonogashira coupling of aldehyde 13 with ortho-diiodobenzene (14).
Scheme 6: Preparation of benzologs of dimers 11/12.
Figure 3: Above: The molecule of compound 19 in the crystal; ellipsoids represent 50% probability levels. Sol...
Figure 4: Above: One of the three independent molecules of compound 20 in the crystal; ellipsoids represent 3...
Scheme 7: Cross dimerization of 1 and 4.
Figure 5: The molecule of compound 22 in the crystal; ellipsoids represent 50% probability levels.
Scheme 8: An attempt to prepare a biphenylenophane.
Figure 6: The molecule of compound 26 in the crystal; ellipsoids represent 50% probability levels.
The influence of intraannular templates on the liquid crystallinity of shape-persistent macrocycles
- Joscha Vollmeyer,
- Ute Baumeister and
- Sigurd Höger
Beilstein J. Org. Chem. 2014, 10, 910–920, doi:10.3762/bjoc.10.89
- 4, 06120 Halle (Saale), Germany 10.3762/bjoc.10.89 Abstract A series of shape-persistent phenylene–ethynylene–naphthylene–butadiynylene macrocycles with different extraannular alkyl groups and intraannular bridges is synthesized by oxidative Glaser-coupling of the appropriate precursors. The
- longer intraannular alkyl bridge of 1b prevents a close packing of the rings and leads in this case even to the absence of the lc phase. Conclusion In summary, shape-persistent macrocycles with intraannular bridges were synthesized by oxidative Glaser-coupling of the appropriate acetylenes. The bridges
Graphical Abstract
Figure 1: Shape-persistent macrocycles with different peripheral side groups and intraannular templates.
Scheme 1: Synthesis of macrocycle 1a with an intraannular undecanedioxy bridge. a: Pd(PPh3)2Cl2, PPh3, CuI, p...
Figure 2: GPC elugrams of the crude product of the cyclization reaction of 1a (—) and 1d (- - -), respectivel...
Scheme 2: Synthesis of the template free macrocycle 1d. a: Pd(PPh3)2Cl2, PPh3, CuI, piperidine, 98%; b: TBAF,...
Figure 3: (a) Melting points (Tm) and clearing points (Tcl) of macrocycles with different interior. [a]First ...
Figure 4: POM images of (a) 1a (20×, 133 °C, upon cooling); (b) 1d (20×, 84 °C, upon heating).
Figure 5: 2D X-ray patterns for 1d: (a) isotropic liquid at 160 °C, (b) partially aligned liquid crystalline ...
Figure 6: 2D X-ray patterns for 1a: (a) isotropic liquid at 150 °C, (b) columnar mesophase at 100 °C, surface...
Figure 7: Model of the molecular packing in the columnar mesophase of 1a: (a) 2D packing scheme for the colum...
Rapid pseudo five-component synthesis of intensively blue luminescent 2,5-di(hetero)arylfurans via a Sonogashira–Glaser cyclization sequence
- Fabian Klukas,
- Alexander Grunwald,
- Franziska Menschel and
- Thomas J. J. Müller
Beilstein J. Org. Chem. 2014, 10, 672–679, doi:10.3762/bjoc.10.60
- in a pseudo five-component reaction via a Sonogashira–Glaser coupling sequence followed by a superbase-mediated (KOH/DMSO) cyclization in a consecutive one-pot fashion. Besides the straightforward synthesis of natural products and biologically active molecules all representatives are particularly
Graphical Abstract
Scheme 1: Sonogashira–Glaser sequence in DMSO as a solvent.
Scheme 2: Pseudo five-component Sonogashira–Glaser cyclisation synthesis of 2,5-di(hetero)arylfurans 2 (aobta...
Figure 1: Compounds 2d (solid and THF solution) and 2n (solid and THF solution) (from left to right) under da...
Figure 2: Selected computed minimum conformations of the 2,5-diarylfurans 2i, 2j, and 2n.
Figure 3: Kohn–Sham HOMOs (bottom) and LUMOs (top) of the compounds 2i, 2j, and 2n (calculated on the DFT lev...
Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition
- Regina Berg and
- Bernd F. Straub
Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308
- with quantitative conversion to give the 1,4-disubstituted 1,2,3-triazole exclusively. Common side reactions such as the Glaser coupling [9][10][11] are not observed. The presented reaction conditions are compatible with a variety of functional groups such as ester, ether, amide, thioether, Fmoc and
- (I) oxidation state in aqueous solution [14][64]. This is important as Cu(II) ions are harmful to this experiment in two ways: on the one hand, Cu(II) ions catalyze the oxidative coupling of the alkyne substrates to give diynes as undesired byproducts (Glaser coupling [9][10][11], Eglinton coupling
- incorporation of iodide in CuAAC reactions of terminal alkynes mediated by CuI (1.0 equivalent) by adequate choice of the base present in the reaction mixture [141]. With a ratio of alkyne/azide/DMAP/CuI = 1.0/3.0/0.3/1.0, they obtained 96% of the 5-iodotriazole and 4% of the Glaser coupling product. Dzyuba has
Graphical Abstract
Scheme 1: Exemplary 1,3-dipolar cycloaddition of phenylacetylene with phenyl azide [6].
Scheme 2: CuAAC reaction of benzyl azide with (prop-2-yn-1-yloxy)benzene [12].
Scheme 3: Bioconjugation reaction of capsid-bound azide groups with alkynyl-functionalized dye molecules (cow...
Figure 1: Tris(triazolylmethyl)amine ligands for CuAAC applications in bioorganic chemistry: TBTA = tris[(1-b...
Figure 2: Derivatives of 2,2’-bipyridine and 1,10-phenanthroline, commonly used ligands in CuAAC reactions un...
Scheme 4: CuAAC reaction with copper(II) precursor salt and rate-accelerating monodentate phosphoramidite lig...
Scheme 5: Synthesis of 1-(adamant-1-yl)-1H-1,2,3-triazol-4-ylcarbonyl-Phe-Gly-OH by solid-supported Click cat...
Scheme 6: CuAAC reaction with re-usable copper(I)-tren catalyst [129].
Scheme 7: CuAAC test reaction with chlorido[tris(1-benzyl-1H-1,2,3-triazol-4-yl)methanol-κ3N3]copper(I) and a...
Scheme 8: CuAAC model reaction with [Cu2(μ-TBTA-κ4N2,N3,N3’,N3’’)2][BF4]2 [131].
Scheme 9: Application of a (2-aminoarenethiolato)copper(I) complex as homogeneous catalyst for the CuAAC test...
Scheme 10: Application of [CuBr(PPh3)3] as homogeneous catalyst for the CuAAC test reaction of benzyl azide wi...
Figure 3: Phosphinite and phosphonite copper(I) complexes presented by Díez-González [144].
Scheme 11: Effect of additives on the CuAAC test reaction with [(SIMes)CuCl] [149].
Scheme 12: Initiation of the catalytic cycle by formation of the copper acetylide intermediate from [(ICy)2Cu]...
Scheme 13: Early mechanistic proposal by Sharpless [12,42].
Scheme 14: Chemoselective synthesis of a 5-iodo-1,4-disubstituted 1,2,3-triazole [156].
Scheme 15: Mechanistic proposals for the copper-catalyzed azide–iodoalkyne cycloaddition [156].
Scheme 16: 1,3-Dipolar cycloaddition of 3-hexyne catalyzed by [(SIMes)CuBr] [146].
Scheme 17: Mechanistic picture for the cycloaddition of internal alkynes catalyzed by NHC-copper(I) complexes ...
Scheme 18: Catalytic cycle of the CuAAC reaction on the basis of the proposed mechanistic scheme by Fokin and ...
Figure 4: Schematic representation of the single crystal X-ray structures of copper(I) acetylide complexes [Cu...
Figure 5: Acetylide-bridged dicopper complexes with tris(heteroarylmethyl)amine ligand(s) as key intermediate...
Scheme 19: Off-cycle equilibrium between unreactive polymeric copper(I) acetylide species (right) and reactive...
Figure 6: Categories of tris(heteroarylmethyl)amine ligands regarding their binding ability to copper(I) ions ...
Scheme 20: Mechanistic scheme for ligand-accelerated catalysis with tripodal tris(heteroarylmethyl)amine ligan...
Scheme 21: Synthesis of supposed intermediates in the CuAAC’s catalytic cycle [164,187].
Figure 7: Tetranuclear copper acetylide complexes as reported by Weiss (left) [176] and Tasker (middle) [185] and model...
Figure 8: Gibbs free energy diagram for the computed mechanistic pathway of the CuAAC reaction starting from ...
Figure 9: Energy diagram by Ahlquist and Fokin [125].
Scheme 22: Mechanistic proposal for the CuAAC reaction based on DFT calculations by Fokin [125] and our group [186] ([Cu...
Figure 10: ORTEP plot [202,203] of the X-ray powder diffraction crystal structure of (phenylethynyl)copper(I) [(PhC≡CCu)...
Scheme 23: Synthesis of [(PhC≡CCu)2]n as co-product in the Glaser coupling of phenylacetylene in the presence ...
Scheme 24: Mechanistic explanation for the isotopic enrichment in the product triazolide in the presence of th...
Scheme 25: Homogeneous CuAAC catalysis with a bistriazolylidene dicopper complex (0.5 mol %) and comparison wi...
The chemistry of bisallenes
- Henning Hopf and
- Georgios Markopoulos
Beilstein J. Org. Chem. 2012, 8, 1936–1998, doi:10.3762/bjoc.8.225
Graphical Abstract
Figure 1: Loschmidt’s structure proposal for benzene (1) (Scheme 181 from [3]) and the corresponding modern stru...
Figure 2: The first isolated bisallenes.
Figure 3: Carbon skeletons of selected bisallenes discussed in this review.
Scheme 1: The preparation of 1,2,4,5-hexatetraene (2).
Scheme 2: The preparation of a conjugated bisallene by the DMS-protocol.
Scheme 3: Preparation of the 3-deuterio- and 3,4-dideuterio derivatives of 24.
Scheme 4: A versatile method to prepare alkylated conjugated bisallenes and other allenes.
Scheme 5: A preparation of 3,4-dimethyl-1,2,4,5-hexatetraene (38).
Scheme 6: A (C6 + 0)-approach to 1,2,4,5-hexatetraene (2).
Scheme 7: The preparation of a fully alkylated bisallenes from a 2,4-hexadiyne-1,6-diol diacetate.
Scheme 8: The preparation of the first phenyl-substituted conjugated bisallenes 3 and 4.
Scheme 9: Selective hydrogenation of [5]cumulenes to conjugated bisallenes: another (C6 + 0)-route.
Scheme 10: Aryl-substituted conjugated bisallenes by a (C3 + C3)-approach.
Scheme 11: Hexaphenyl-1,2,4,5-hexatetraene (59) by a (C3 + C3)-approach.
Scheme 12: An allenation route to conjugated bisallenes.
Scheme 13: The preparation of 3,4-difunctionalized conjugated bisallenes.
Scheme 14: Problems during the preparation of sulfur-substituted conjugated bisallenes.
Scheme 15: The preparation of 3,4-dibromo bisallenes.
Scheme 16: Generation of allenolates by an oxy-Cope rearrangement.
Scheme 17: A linear trimerization of alkynes to conjugated bisallenes: a (C2 + C2 + C2)-protocol.
Scheme 18: Preparation of a TMS-substituted conjugated bisallene by a C3-dimerization route.
Scheme 19: A bis(trimethylsilyl)bisallene by a C3-coupling protocol.
Scheme 20: The rearrangement of highly substituted benzene derivatives into their conjugated bisallenic isomer...
Scheme 21: From fully substituted benzene derivatives to fully substituted bisallenes.
Scheme 22: From a bicyclopropenyl to a conjugated bisallene derivative.
Scheme 23: The conversion of a bismethylenecyclobutene into a conjugated bisallene.
Scheme 24: The preparation of monofunctionalized bisallenes.
Scheme 25: Preparation of bisallene diols and their cyclization to dihydrofurans.
Scheme 26: A 3,4-difunctionalized conjugated bisallene by a C3-coupling process.
Scheme 27: Preparation of a bisallenic diketone by a coupling reaction.
Scheme 28: Sulfur and selenium-substituted bisallenes by a [2.3]sigmatropic rearrangement.
Scheme 29: The biallenylation of azetidinones.
Scheme 30: The preparation of a fully ferrocenylated conjugated bisallene.
Scheme 31: The first isomerization of a 1,5-hexadiyne to a 1,2,4,5-hexatetraene.
Scheme 32: The preparation of alkynyl-substituted bisallenes by a C3-dimerization protocol.
Scheme 33: Preparation of another completely ferrocenylated bisallene.
Scheme 34: The cyclization of 1,5-hexadiyne (129) to 3,4-bismethylenecyclobutene (130) via 1,2,4,5-hexatetraen...
Scheme 35: Stereochemistry of the thermal cyclization of bisallenes to bismethylenecyclobutenes.
Scheme 36: Bisallene→bismethylenecyclobutene ring closures in the solid state.
Scheme 37: A bisallene cyclization/dimerization reaction.
Scheme 38: A selection of Diels–Alder additions of 1,2,4,5-hexatetraene with various double-bond dienophiles.
Scheme 39: The stereochemistry of the [2 + 4] cycloaddition to conjugated bisallenes.
Scheme 40: Preparation of azetidinone derivatives from conjugated bisallenes.
Scheme 41: Cycloaddition of heterodienophiles to a conjugated bisallene.
Scheme 42: Addition of triple-bond dienophiles to conjugated bisallenes.
Scheme 43: Sulfur dioxide addition to conjugated bisallenes.
Scheme 44: The addition of a germylene to a conjugated bisallene.
Scheme 45: Trapping of conjugated bisallenes with phosphinidenes.
Scheme 46: The cyclopropanantion of 1,2,4,5-hexatetraene (2).
Scheme 47: Photochemical reactions involving conjugated bisallenes.
Scheme 48: Base-catalyzed isomerizations of conjugated bisallenes.
Scheme 49: Ionic additions to a conjugated bisallene.
Scheme 50: Oxidation reactions of a conjugated bisallene.
Scheme 51: The mechanism of oxidation of the bisallene 24.
Scheme 52: CuCl-catalyzed cyclization of 1,2,4,5-hexatetraene (2).
Scheme 53: The conversion of conjugated bisallenes into cyclopentenones.
Scheme 54: Oligomerization of a conjugated bisallene by nickel catalysts.
Scheme 55: Generation of 1,2,5,6-heptatetraene (229) as a reaction intermediate.
Scheme 56: The preparation of a stable derivative of 1,2,5,6-heptatetraene.
Scheme 57: A bisallene with a carbonyl group as a spacer element.
Scheme 58: The first preparation of 1,2,6,7-octatetraene (242).
Scheme 59: Preparation of 1,2,6,7-octatetraenes by (C4 + C4)-coupling of enynes.
Scheme 60: Preparation of 1,2,6,7-octatetraenes by (C4 + C4)-coupling of homoallenyl bromides.
Scheme 61: Preparation of 1,2,6,7-octatetraenes by alkylation of propargylic substrates.
Scheme 62: Preparation of two highly functionalized 1,2,6,7-octatetraenes.
Scheme 63: Preparation of several higher α,ω-bisallenes.
Scheme 64: Preparation of different alkyl derivatives of α,ω-bisallenes.
Scheme 65: The preparation of functionalized 1,2,7,8-nonatetraene derivatives.
Scheme 66: Preparation of functionalized α,ω-bisallenes.
Scheme 67: The preparation of an α,ω-bisallene by direct homologation of an α,ω-bisalkyne.
Scheme 68: The gas-phase pyrolysis of 4,4-dimethyl-1,2,5,6-heptatetraene (237).
Scheme 69: Gas-phase pyrolysis of 1,2,6,7-octatetraene (242).
Scheme 70: The cyclopropanation of 1,2,6,7-octatetraene (242).
Scheme 71: Intramolecular cyclization of 1,2,6,7-octatetraene derivatives.
Scheme 72: The gas-phase pyrolysis of 1,2,7,8-nonatetraene (265) and 1,2,8,9-decatetraene (266).
Scheme 73: Rh-catalyzed cyclization of a functionalized 1,2,7,8-nonatetraene.
Scheme 74: A triple cyclization involving two different allenic substrates.
Scheme 75: Bicyclization of keto derivatives of 1,2,7,8-nonatetraene.
Scheme 76: The preparation of complex organic compounds from functionalized bisallenes.
Scheme 77: Cycloisomerization of an α,ω-bisallene containing a C9 tether.
Scheme 78: Organoborane polymers from α,ω-bisallenes.
Scheme 79: Preparation of trans- (337) and cis-1,2,4,6,7-octapentaene (341).
Scheme 80: The preparation of 4-methylene-1,2,5,6-heptatetraene (349).
Scheme 81: The preparation of acetylenic bisallenes.
Scheme 82: The preparation of derivatives of hydrocarbon 351.
Scheme 83: The construction of macrocyclic alleno-acetylenes.
Scheme 84: Preparation and reactions of 4,5-bismethylene-1,2,6,7-octatetraene (365).
Scheme 85: Preparation of 1,2-bis(propadienyl)benzene (370).
Scheme 86: The preparation of 1,4-bis(propadienyl)benzene (376).
Scheme 87: The preparation of aromatic and heteroaromatic bisallenes by metal-mediated coupling reactions.
Scheme 88: Double cyclization of an aromatic bisallene.
Scheme 89: Preparation of an allenic [15]paracyclophane by a ring-closing metathesis reaction of an aromatic α...
Scheme 90: Preparation of a macrocyclic ring system containing 1,4-bis(propadienyl)benzene units.
Scheme 91: Preparation of copolymers from 1,4-bis(propadienyl)benzene (376).
Scheme 92: A boration/copolymerization sequence of an aromatic bisallene and an aromatic bisacetylene.
Scheme 93: Formation of a layered aromatic bisallene.
Figure 4: The first members of the semicyclic bisallene series.
Scheme 94: Preparation of the first bis(vinylidene)cyclobutane derivative.
Scheme 95: Dimerization of strain-activated cumulenes to bis(vinylidene)cyclobutanes.
Scheme 96: Photodimerization of two fully substituted butatrienes in the solid state.
Scheme 97: Preparation of the two parent bis(vinylidene)cyclobutanes.
Scheme 98: The preparation of 1,3-bis(vinylidene)cyclopentane and its thermal isomerization.
Scheme 99: The preparation of the isomeric bis(vinylidene)cyclohexanes.
Scheme 100: Bi- and tricyclic conjugated bisallenes.
Scheme 101: A selection of polycyclic bisallenes.
Scheme 102: The first endocyclic bisallenes.
Figure 5: The stereochemistry of 1,2,6,7-cyclodecatetraene.
Scheme 103: The preparation of several endocyclic bisallenes.
Scheme 104: Synthesis of diastereomeric derivatives of 1,2,6,7-cyclodecatetraene.
Scheme 105: Preparation of a derivative of 1,2,8,9-cyclotetradecatetraene.
Scheme 106: The preparation of keto derivatives of cyclic bisallenes.
Scheme 107: The preparation of cyclic biscumulenic ring systems.
Scheme 108: Cyclic bisallenes in natural- and non-natural-product chemistry.
Scheme 109: The preparation of iron carbonyl complexes from cyclic bisallenes.
Figure 6: A selection of unknown exocyclic bisallenes that should have interesting chemical properties.
Scheme 110: The thermal isomerization of 1,2-diethynylcyclopropanes and -cyclobutanes.
Scheme 111: Intermediate generation of a cyclooctapentaene.
Scheme 112: Attempted preparation of a cyclodecahexaene.
Scheme 113: The thermal isomerization of 1,5,9-cyclododecatriyne (511) into [6]radialene (514).
Scheme 114: An isomerization involving a diketone derived from a conjugated bisallene.
Scheme 115: Typical reaction modes of heteroorganic bisallenes.
Scheme 116: Generation and thermal behavior of acyclic hetero-organic bisallenes.
Scheme 117: Generation of bis(propadienyl)thioether.
Scheme 118: The preparation of a bisallenic sulfone and its thermal isomerization.
Scheme 119: Bromination of the bisallenic sulfone 535.
Scheme 120: Metalation/hydrolysis of the bisallenic sulfone 535.
Scheme 121: Aromatic compounds from hetero bisallenes.
Scheme 122: Isomerization/cyclization of bispropargylic ethers.
Scheme 123: The preparation of novel aromatic systems by base-catalyzed isomerization of bispropargyl ethers.
Scheme 124: The isomerization of bisacetylenic thioethers to bicyclic thiophenes.
Scheme 125: Aromatization of macrocyclic bispropargylic sulfides.
Scheme 126: Preparation of ansa-compounds from macrocyclic bispropargyl thioethers.
Scheme 127: Alternate route for cyclization of a heterorganic bisallene.
Scheme 128: Multiple isomerization/cyclization of “double” bispropargylic thioethers.
Scheme 129: Preparation of a bisallenyl disulfide and its subsequent bicyclization.
Scheme 130: Thermal cyclization of a bisallenyl thiosulfonate.
Scheme 131: Some reactions of heteroorganic bisallenes with two sulfur atoms.
Scheme 132: Further methods for the preparation of heteroorganic bisallenes.
Scheme 133: Cyclization reactions of heteroorganic bisallenes.
Scheme 134: Thermal cycloadditions of bisallenic tertiary amines.
Scheme 135: Cyclization of a bisallenic tertiary amine in the presence of a transition-metal catalyst.
Scheme 136: A Pauson–Khand reaction of a bisallenic ether.
Scheme 137: Formation of a 2:1adduct from two allenic substrates.
Scheme 138: A ring-forming silastannylation of a bisallenic tertiary amine.
Scheme 139: A three-component cyclization involving a heterorganic bisallene.
Scheme 140: Atom-economic construction of a complex organic framework from a heterorganic α,ω-bisallene.
Pseudo five-component synthesis of 2,5-di(hetero)arylthiophenes via a one-pot Sonogashira–Glaser cyclization sequence
- Dominik Urselmann,
- Dragutin Antovic and
- Thomas J. J. Müller
Beilstein J. Org. Chem. 2011, 7, 1499–1503, doi:10.3762/bjoc.7.174
- Dominik Urselmann Dragutin Antovic Thomas J. J. Muller Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany 10.3762/bjoc.7.174 Abstract Based upon a consecutive one-pot Sonogashira–Glaser coupling
- taking advantage of the high yield Sonogashira–Glaser coupling synthesis [15] of 1,4-diphenylbutadiyne starting from iodobenzene (1a) (Table 1). In addition, the final cyclization step to give 2,5-diphenylthiophene (2a) was performed under microwave heating at 120 °C for a hold time of 2 h. The solvent
- elemental analysis, compound 2j was obtained as a bishydrochloride. eN-Boc 3-iodo indole (1p) was applied as a starting material. Concept of a Sonogashira–Glaser coupling sequence. Concept of a Sonogashira–Glaser cyclization synthesis of 2,5-di(hetero)arylthiophenes. Pseudo five-component Sonogashira–Glaser
Graphical Abstract
Scheme 1: Concept of a Sonogashira–Glaser coupling sequence.
Scheme 2: Concept of a Sonogashira–Glaser cyclization synthesis of 2,5-di(hetero)arylthiophenes.
Scheme 3: Pseudo five-component Sonogashira–Glaser cyclization synthesis of symmetrical 2,5-di(hetero)arylthi...
Figure 1: Symmetrical 2,5-di(hetero)arylthiophenes 2 synthesized via the one-pot pseudo five-component Sonoga...
Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers
- Daniel Crespy and
- Katharina Landfester
Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130
- polymer dissolved in toluene. The synthesis of fluorescent conjugated particles of poly(arylene diethynylenes) in direct miniemulsions by Glaser coupling has also been reported [133]. 4,4'-Dinonyl-2,2'-bipyridine was found to be a suitable ligand for solubilizing the copper(I) chloride catalyst in the
Graphical Abstract
Figure 1: Copolymerization of 2 monomers A and B with different polarities in direct miniemlusions with the d...
Figure 2: Interfacial alternating radical copolymerization between dibutyl maleate and vinyl gluconamide for ...
Figure 3: Chemical structures of the surfmers for radical polymerization in miniemulsions: a: sodium vinylben...
Scheme 1: Synthesis of the macroinitiator for ROMP in direct miniemulsion [71].
Figure 4: Monomers used in ionic miniemulsion polymerization. a: octamethylcyclotetrasiloxane [9,74], b: 1,3,5-tris...
Figure 5: Enzymatic reactions in miniemulsion droplets (reproduced with permission from [91]. Copyright (2003) Wi...
Figure 6: Chemical structure of a: polyaniline (leucoemeraldine), b: polypyrrole, c: poly(ethylene dioxythiop...
Figure 7: Transmission electron micrograph of polyurethane capsules synthesized by interfacial polyaddition i...
Figure 8: Schematics for the polycondensation reaction between hydrophobic alcohols and carboxylic acids surr...
Scheme 2: Polyimide from the reaction performed in the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoro...
Figure 9: a: TEM micrograph of the cubic structures, b: proposed mechanism for the production of the nanocube...
Polar tagging in the synthesis of monodisperse oligo(p-phenyleneethynylene)s and an update on the synthesis of oligoPPEs
- Dhananjaya Sahoo,
- Susanne Thiele,
- Miriam Schulte,
- Navid Ramezanian and
- Adelheid Godt
Beilstein J. Org. Chem. 2010, 6, No. 57, doi:10.3762/bjoc.6.57
- simple – but is especially satisfying because of a trouble-free separation of the desired alkynyl–aryl coupling product and the accompanying oxidative alkyne dimerization product (Glaser coupling product). In our experience, under the standard coupling conditions – i.e. Pd(PPh3)2Cl2, CuI, piperidine, THF
- , room temperature – Glaser coupling is much faster than the alkynyl–aryl coupling. Therefore, even traces of oxygen in the reaction vessel will lead to alkyne dimerization. Furthermore, most experimentalists prefer to work up the reaction mixtures under standard conditions which means exposing the
- reaction mixture to air. Opening the flask will immediately cause any unreacted terminal alkyne to undergo Glaser coupling. This is of no concern provided the alkyne dimer and the alkynyl–aryl coupling product can be easily separated, and this is what the HOM and related HOP group guarantee since they act
Graphical Abstract
Scheme 1: Synthesis of oligoPPEs by a unidirectional (a) or bidirectional (b) repeating unit by repeating uni...
Scheme 2: Three divergent-convergent routes to oligoPPEs. R denotes solubilising substituents such as hexyl.
Scheme 3: Synthesis of the building blocks 11, 21, and 31. The depicted alkene configuration of 5 was chosen ...
Scheme 4: Carbometalation, an occasionally detected side reaction. The depicted alkene configuration was chos...
Scheme 5: Iodination of 1,4-dihexylbenzene.
Scheme 6: Different routes to compound 14, a representative of the large group of functionalized oligoPPEs.
