Vinylphosphonium and 2-aminovinylphosphonium salts – preparation and applications in organic synthesis
- Anna Kuźnik,
- Roman Mazurkiewicz and
- Beata Fryczkowska
Beilstein J. Org. Chem. 2017, 13, 2710–2738, doi:10.3762/bjoc.13.269
Graphical Abstract
Scheme 1: Generation of phosphorus ylides from vinylphosphonium salts.
Scheme 2: Intramolecular Wittig reaction with the use of vinylphosphonium salts.
Scheme 3: Alkylation of diphenylvinylphosphine with methyl or benzyl iodide.
Scheme 4: Methylation of isopropenyldiphenylphosphine with methyl iodide.
Scheme 5: Alkylation of phosphines with allyl halide derivatives and subsequent isomerization of intermediate...
Scheme 6: Alkylation of triphenylphosphine with vinyl triflates in the presence of (Ph3P)4Pd.
Scheme 7: Mechanism of alkylation of triphenylphosphine with vinyl triflates in the presence of (Ph3P)4Pd as ...
Scheme 8: β-Elimination of phenol from β-phenoxyethyltriphenylphosphonium bromide.
Scheme 9: β-Elimination of phenol from β-phenoxyethylphosphonium salts in an alkaline environment.
Scheme 10: Synthesis and subsequent dehydrohalogenation of α-bromoethylphosphonium bromide.
Scheme 11: Synthesis of tributylvinylphosphonium iodides via Peterson-type olefination of α-trimethylsilylphos...
Scheme 12: Synthesis of 1-cycloalkenetriphenylphosphonium salts by electrochemical oxidation of triphenylphosp...
Scheme 13: Suggested mechanism for the electrochemical synthesis of 1-cycloalkenetriphenylphosphonium salts.
Scheme 14: Generation of α,β-(dialkoxycarbonyl)vinylphosphonium salts by addition of triphenylphosphine to ace...
Scheme 15: Synthesis of 2-(N-acylamino)vinylphosphonium halides by imidoylation of β-carbonyl ylides with imid...
Scheme 16: Imidoylation of β-carbonyl ylides with imidoyl halides generated in situ.
Scheme 17: Synthesis of 2-benzoyloxyvinylphosphonium bromide from 2-propynyltriphenylphosphonium bromide.
Scheme 18: Synthesis of 2-aminovinylphosphonium salts via nucleophilic addition of amines to 2-propynyltriphen...
Scheme 19: Deacylation of 2-(N-acylamino)vinylphosphonium chlorides to 2-aminovinylphosphonium salts.
Scheme 20: Resonance structures of 2-aminovinylphosphonium salts and tautomeric equilibrium between aminovinyl...
Scheme 21: Synthesis of 2-aminovinylphosphonium salts by reaction of (formylmethyl)triphenylphosphonium chlori...
Scheme 22: Generation of ylides by reaction of vinyltriphenylphosphonium bromide with nucleophiles and their s...
Scheme 23: Intermolecular Wittig reaction with the use of vinylphosphonium bromide and organocopper compounds ...
Scheme 24: Intermolecular Wittig reaction with the use of ylides generated from vinylphosphonium bromides and ...
Scheme 25: Direct transformation of vinylphosphonium salts into ylides in the presence of potassium tert-butox...
Scheme 26: A general method for synthesis of carbo- and heterocyclic systems by the intramolecular Wittig reac...
Scheme 27: Synthesis of 2H-chromene by reaction of vinyltriphenylphosphonium bromide with sodium 2-formylpheno...
Scheme 28: Synthesis of 2,5-dihydro-2,3-dimethylfuran by reaction of vinylphosphonium bromide with 3-hydroxy-2...
Scheme 29: Synthesis of 2H-chromene and 2,5-dihydrofuran derivatives in the intramolecular Wittig reaction wit...
Scheme 30: Enantioselective synthesis of 3,6-dihydropyran derivatives from vinylphosphonium bromide and enanti...
Scheme 31: Synthesis of 2,5-dihydrothiophene derivatives in the intramolecular Wittig reaction from vinylphosp...
Scheme 32: Synthesis of bicyclic pyrrole derivatives in the reaction of vinylphosphonium halides and 2-pyrrolo...
Scheme 33: Stereoselective synthesis of bicyclic 2-pyrrolidinone derivatives in the reaction of vinylphosphoni...
Scheme 34: Stereoselective synthesis of 3-pyrroline derivatives in the intramolecular Wittig reaction from vin...
Scheme 35: Synthesis of cyclic alkenes in the intramolecular Wittig reaction from vinylphosphonium bromide and...
Scheme 36: Synthesis of 1,3-cyclohexadienes by reaction of 1,3-butadienyltriphenylphosphonium bromide with eno...
Scheme 37: Synthesis of bicyclo[3.3.0]octenes by reaction of vinylphosphonium salts with cyclic diketoester.
Scheme 38: Synthesis of quinoline derivatives in the intramolecular Wittig reaction from 2-(2-acylphenylamino)...
Scheme 39: Stereoselective synthesis of γ-aminobutyric acid in the intermolecular Wittig reaction from chiral ...
Scheme 40: Synthesis of allylamines in the intermolecular Wittig reaction from 2-aminovinylphosphonium bromide...
Scheme 41: A general route towards α,β-di(alkoxycarbonyl)vinylphosphonium salts and their subsequent possible ...
Scheme 42: Generation of resonance-stabilized phosphorus ylides via the reaction of triphenylphosphine with di...
Scheme 43: Synthesis of resonance-stabilized phosphorus ylides in the reaction of triphenylphosphine, dialkyl ...
Scheme 44: Synthesis of resonance-stabilized phosphorus ylides via the reaction of triphenylphosphine with dia...
Scheme 45: Generation of resonance-stabilized phosphorus ylides in the reaction of acetylenedicarboxylate, tri...
Scheme 46: Synthesis of resonance-stabilized phosphorus ylides via the reaction of dialkyl acetylenedicarboxyl...
Scheme 47: Synthesis of resonance-stabilized ylides derived from semicarbazones, aromatic amides, and 3-(aryls...
Scheme 48: Synthesis of resonance-stabilized ylides via the reaction of triphenylphosphine with dialkyl acetyl...
Scheme 49: Synthesis of resonance-stabilized ylides in the reaction of triphenylphosphine, dialkyl acetylenedi...
Scheme 50: Synthesis of N-acylated α,β-unsaturated γ-lactams via resonance-stabilized phosphorus ylides derive...
Scheme 51: Synthesis of resonance-stabilized phosphorus ylides derived from 6-amino-N,N'-dimethyluracil and th...
Scheme 52: Generation of resonance-stabilized phosphorus ylides in the reaction of triphenylphosphine, dialkyl...
Scheme 53: Synthesis of resonance-stabilized phosphorus ylides via the reaction of triphenylphosphine with dia...
Scheme 54: Synthesis of 1,3-dienes via intramolecular Wittig reaction with the use of resonance-stabilized yli...
Scheme 55: Synthesis of 1,3-dienes in the intramolecular Wittig reaction from ylides generated from dimethyl a...
Scheme 56: Synthesis of 4-(2-quinolyl)cyclobutene-1,2,3-tricarboxylic acid triesters and isomeric cyclopenteno...
Scheme 57: Synthesis of 4-arylquinolines via resonance-stabilized ylides in the intramolecular Wittig reaction....
Scheme 58: Synthesis of furan derivatives via resonance-stabilized ylides in the intramolecular Wittig reactio...
Scheme 59: Synthesis of 1,3-indanedione derivatives via resonance-stabilized ylides in the intermolecular Witt...
Scheme 60: Synthesis of coumarin derivatives via nucleophilic displacement of the triphenylphosphonium group i...
Scheme 61: Synthesis of 6-formylcoumarin derivatives and their application in the synthesis of dyads.
Scheme 62: Synthesis of di- and tricyclic coumarin derivatives in the reaction of pyrocatechol with two vinylp...
Scheme 63: Synthesis of mono-, di-, and tricyclic derivatives in the reaction of pyrogallol with one or two vi...
Scheme 64: Synthesis of 1,4-benzoxazine derivative by nucleophilic displacement of the triphenylphosphonium gr...
Scheme 65: Synthesis of 7-oxo-7H-pyrido[1,2,3-cd]perimidine derivative via nucleophilic displacement of the tr...
Scheme 66: Application of vinylphosphonium salts in the Diels–Alder reaction with dienes.
Scheme 67: Synthesis of pyrroline derivatives from vinylphosphonium bromide and 5-(4H)-oxazolones.
Scheme 68: Synthesis of pyrrole derivatives in the reactions of vinyltriphenylphosphonium bromide with protona...
Scheme 69: Synthesis of dialkyl 2-(alkylamino)-5-aryl-3,4-furanedicarboxylates via intermediate α,β-di(alkoxyc...
Scheme 70: Synthesis of 1,4-benzoxazine derivatives from acetylenedicarboxylates, phosphines, and 1-nitroso-2-...
Reagent-controlled regiodivergent intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and β-ketoamides
- Irwan Iskandar Roslan,
- Kian-Hong Ng,
- Gaik-Khuan Chuah and
- Stephan Jaenicke
Beilstein J. Org. Chem. 2017, 13, 2739–2750, doi:10.3762/bjoc.13.270
Graphical Abstract
Scheme 1: Two different intermolecular cyclization pathways controlled by reagents used.
Scheme 2: Scope of reaction. Reaction conditions: 1 (1.2 mmol), 2 (1.0 mmol), KOt-Bu (2 mmol), in 3 mL CBrCl3...
Scheme 3: Scope of the reaction. Reaction conditions: 1 (1.0 mmol), 2 (1.5 mmol), In(OTf)3 (0.1 mmol), in 1.5...
Scheme 4: Control experiments.
Figure 1: Proposed mechanism (benzo[d]imidazo[2,1-b]thiazoles).
Figure 2: Proposed mechanism (benzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones).
Binding abilities of polyaminocyclodextrins: polarimetric investigations and biological assays
- Marco Russo,
- Daniele La Corte,
- Annalisa Pisciotta,
- Serena Riela,
- Rosa Alduina and
- Paolo Lo Meo
Beilstein J. Org. Chem. 2017, 13, 2751–2763, doi:10.3762/bjoc.13.271
Graphical Abstract
Figure 1: Structures of: a) AmCDs CD1–3; b) p-nitroaniline guests 1–4; c) sodium alginate (Alg).
Figure 2: Trends of the molar optical rotation Θ of AmCDs CD1–3 vs pH.
Figure 3: Trends of the molar optical rotation Θ of AmCDs vs χH+.
Figure 4: Polarimetric data trends for the inclusion of 4 in CD1 at different pH values.
Figure 5: Possible association of AmCDs with guests 2–4.
Figure 6: Polarimetric data trends for the CD1–Alg interaction (with buffer).
Figure 7: nr Values for the AmCD–Alg interaction as a function of <nH+>.
Figure 8: Electrophoretic mobility shift assays of pDNA in the presence of AmCDs at different N/P ratios, as ...
CF3SO2X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation. Part 1: Use of CF3SO2Na
- Hélène Guyon,
- Hélène Chachignon and
- Dominique Cahard
Beilstein J. Org. Chem. 2017, 13, 2764–2799, doi:10.3762/bjoc.13.272
Graphical Abstract
Scheme 1: Trifluoromethylation of enol acetates by Langlois.
Scheme 2: Trifluoromethylation of (het)aryl enol acetates.
Scheme 3: Mechanism for the trifluoromethylation of enol acetates.
Scheme 4: Oxidative trifluoromethylation of unactivated olefins and mechanistic pathway.
Scheme 5: Oxidative trifluoromethylation of acetylenic substrates.
Scheme 6: Metal free trifluoromethylation of styrenes.
Scheme 7: Synthesis of α-trifluoromethylated ketones by oxytrifluoromethylation of heteroatom-functionalised ...
Scheme 8: Catalysed photoredox trifluoromethylation of vinyl azides.
Scheme 9: Oxidative difunctionalisation of alkenyl MIDA boronates.
Scheme 10: Synthesis of β-trifluoromethyl ketones from cyclopropanols.
Scheme 11: Aryltrifluoromethylation of allylic alcohols.
Scheme 12: Cascade multicomponent synthesis of nitrogen heterocycles via azotrifluoromethylation of alkenes.
Scheme 13: Photocatalytic azotrifluoromethylation of alkenes with aryldiazonium salts and CF3SO2Na.
Scheme 14: Copper-promoted intramolecular aminotrifluoromethylation of alkenes with CF3SO2Na.
Scheme 15: Oxytrifluoromethylation of alkenes with CF3SO2Na and hydroxamic acid.
Scheme 16: Manganese-catalysed oxytrifluoromethylation of styrene derivatives.
Scheme 17: Oxytrifluoromethylation of alkenes with NMP/O2 and CF3SO2Na.
Scheme 18: Intramolecular oxytrifluoromethylation of alkenes.
Scheme 19: Hydrotrifluoromethylation of styrenyl alkenes and unactivated aliphatic alkenes.
Scheme 20: Hydrotrifluoromethylation of electron-deficient alkenes.
Scheme 21: Hydrotrifluoromethylation of alkenes by iridium photoredox catalysis.
Scheme 22: Iodo- and bromotrifluoromethylation of alkenes by CF3SO2Na/I2O5 or CF3SO2Na / NaBrO3.
Scheme 23: N-methyl-9-mesityl acridinium and visible-light-induced chloro-, bromo- and SCF3 trifluoromethylati...
Scheme 24: Carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na / TBHP by Lipshutz.
Scheme 25: Carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/TBHP reported by Lei.
Scheme 26: Carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/(NH4)2S2O8.
Scheme 27: Metal-free carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/K2S2O8 reported by Wang.
Scheme 28: Metal-free carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/PIDA reported by Fu.
Scheme 29: Metal-free cascade trifluoromethylation/cyclisation of N-arylmethacrylamides (a) and enynes (b) wit...
Scheme 30: Trifluoromethylation/cyclisation of N-arylcinnamamides: Synthesis of 3,4-disubstituted dihydroquino...
Scheme 31: Trifluoromethylation/cyclisation of aromatic-containing unsaturated ketones.
Scheme 32: Chemo- and regioselective cascade trifluoromethylation/heteroaryl ipso-migration of unactivated alk...
Scheme 33: Copper-mediated 1,2-bis(trifluoromethylation) of alkenes.
Scheme 34: Trifluoromethylation of aromatics with CF3SO2Na reported by Langlois.
Scheme 35: Baran’s oxidative C–H trifluoromethylation of heterocycles.
Scheme 36: Trifluoromethylation of acetanilides and anilines.
Scheme 37: Trifluoromethylation of heterocycles in water.
Scheme 38: Trifluoromethylation of coumarins in a continuous-flow reactor.
Scheme 39: Oxidative trifluoromethylation of coumarins, quinolines and pyrimidinones.
Scheme 40: Oxidative trifluoromethylation of pyrimidinones and pyridinones.
Scheme 41: Phosphovanadomolybdic acid-catalysed direct C−H trifluoromethylation.
Scheme 42: Oxidative trifluoromethylation of imidazopyridines and imidazoheterocycles.
Scheme 43: Oxidative trifluoromethylation of imidazoheterocycles and imidazoles in ionic liquid/water.
Scheme 44: Oxidative trifluoromethylation of 8-aminoquinolines.
Scheme 45: Oxidative trifluoromethylation of various 8-aminoquinolines using the supported catalyst CS@Cu(OAc)2...
Scheme 46: Oxidative trifluoromethylation of the naphthylamide 70.
Scheme 47: Oxidative trifluoromethylation of various arenes in the presence of CF3SO2Na and sodium persulfate.
Scheme 48: Trifluoromethylation of electron-rich arenes and unsymmetrical biaryls with CF3SO2Na in the presenc...
Figure 1: Trifluoromethylated coumarin and flavone.
Scheme 49: Metal-free trifluoromethylation catalysed by a photoredox organocatalyst.
Scheme 50: Quinone-mediated trifluoromethylation of arenes and heteroarenes.
Scheme 51: Metal- and oxidant-free photochemical trifluoromethylation of arenes.
Scheme 52: Copper-mediated trifluoromethylation of arenediazonium tetrafluoroborates.
Scheme 53: Oxidative trifluoromethylation of aryl- and heteroarylboronic acids.
Scheme 54: Oxidative trifluoromethylation of aryl- and vinylboronic acids.
Scheme 55: Oxidative trifluoromethylation of unsaturated potassium organotrifluoroborates.
Scheme 56: Oxidative trifluoromethylation of (hetero)aryl- and vinyltrifluoroborates.
Scheme 57: Copper−catalysed decarboxylative trifluoromethylation of cinnamic acids.
Scheme 58: Iron-mediated decarboxylative trifluoromethylation of α,β-unsaturated carboxylic acids.
Scheme 59: Cu/Ag-catalysed decarboxylative trifluoromethylation of cinnamic acids.
Scheme 60: I2O5-Promoted decarboxylative trifluoromethylation of cinnamic acids.
Scheme 61: Silver(I)-catalysed denitrative trifluoromethylation of β-nitrostyrenes.
Scheme 62: Copper-catalysed direct trifluoromethylation of styrene derivatives.
Scheme 63: Transition-metal-free synthesis of β-trifluoromethylated enamines.
Scheme 64: I2O5-mediated iodotrifluoromethylation of alkynes.
Scheme 65: Silver-catalysed tandem trifluoromethylation/cyclisation of aryl isonitriles.
Scheme 66: Photoredox trifluoromethylation of 2-isocyanobiphenyls.
Scheme 67: Trifluoromethylation of potassium alkynyltrifluoroborates with CF3SO2Na.
Scheme 68: N-trifluoromethylation of nitrosoarenes with CF3SO2Na (SQ: semiquinone).
Scheme 69: Trifluoromethylation of disulfides with CF3SO2Na.
Scheme 70: Trifluoromethylation of thiols with CF3SO2Na/I2O5.
Scheme 71: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/(EtO)2P(O)H/CuCl/DMSO.
Scheme 72: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/(EtO)2P(O)H/TMSCl.
Scheme 73: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/PPh3/N-chlorophthalimide.
Scheme 74: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/PCl3.
Scheme 75: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/PCl3.
Scheme 76: Trifluoromethylsulfenylation of aryl iodides with in situ generated CuSCF3 (DMI: 1,3-dimethyl-2-imi...
Scheme 77: Pioneering trifluoromethylsulfinylation of N, O, and C-nucleophiles.
Scheme 78: Trifluoromethylsulfinylation of (1R,2S)-ephedrine (Im: imidazole; DIEA: N,N-diisopropylethylamine).
Scheme 79: Trifluoromethylsulfinylation of substituted benzenes with CF3SO2Na/CF3SO3H.
Scheme 80: Trifluoromethylsulfinylation of indoles with CF3SO2Na/P(O)Cl3.
Scheme 81: Trifluoromethylsulfinylation of indoles with CF3SO2Na/PCl3.
Scheme 82: Formation of triflones from benzyl bromides (DMA: dimethylacetamide).
Scheme 83: Formation of α-trifluoromethylsulfonyl ketones, esters, and amides.
Scheme 84: Allylic trifluoromethanesulfonylation of aromatic allylic alcohols.
Scheme 85: Copper-catalysed couplings of aryl iodonium salts with CF3SO2Na.
Scheme 86: Palladium-catalysed trifluoromethanesulfonylation of aryl triflates and chlorides with CF3SO2Na.
Scheme 87: Copper-catalysed coupling of arenediazonium tetrafluoroborates with CF3SO2Na.
Scheme 88: Synthesis of phenyltriflone via coupling of benzyne with CF3SO2Na.
Scheme 89: Synthesis of 1-trifluoromethanesulfonylcyclopentenes from 1-alkynyl-λ3-bromanes and CF3SO2Na.
Scheme 90: One-pot synthesis of functionalised vinyl triflones.
Scheme 91: Regioselective synthesis of vinyltriflones from styrenes.
Scheme 92: Trifluoromethanesulfonylation of alkynyl(phenyl) iodonium tosylates by CF3SO2Na.
Scheme 93: Synthesis of thio- and selenotrifluoromethanesulfonates.
CF3SO2X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation and chlorination. Part 2: Use of CF3SO2Cl
- Hélène Chachignon,
- Hélène Guyon and
- Dominique Cahard
Beilstein J. Org. Chem. 2017, 13, 2800–2818, doi:10.3762/bjoc.13.273
Graphical Abstract
Scheme 1: Trifluoromethylation of silyl enol ethers.
Scheme 2: Continuous flow trifluoromethylation of ketones under photoredox catalysis.
Scheme 3: Trifluoromethylation of enol acetates.
Scheme 4: Photoredox-catalysed tandem trifluoromethylation/cyclisation of N-arylacrylamides: a route to trifl...
Scheme 5: Tandem trifluoromethylation/cyclisation of N-arylacrylamides using BiOBr nanosheets catalysis.
Scheme 6: Photoredox-catalysed trifluoromethylation/desulfonylation/cyclisation of N-tosyl acrylamides (bpy: ...
Scheme 7: Photoredox-catalysed trifluoromethylation/aryl migration/desulfonylation of N-aryl-N-tosylacrylamid...
Scheme 8: Proposed mechanism for the trifluoromethylation/aryl migration/desulfonylation (/cyclisation) of N-...
Scheme 9: Photoredox-catalysed trifluoromethylation/cyclisation of N-methacryloyl-N-methylbenzamide derivativ...
Scheme 10: Photoredox-catalysed trifluoromethylation/cyclisation of N-methylacryloyl-N-methylbenzamide derivat...
Scheme 11: Photoredox-catalysed trifluoromethylation/dearomatising spirocyclisation of a N-benzylacrylamide de...
Scheme 12: Photoredox-catalysed trifluoromethylation/cyclisation of an unactivated alkene.
Scheme 13: Asymmetric radical aminotrifluoromethylation of N-alkenylurea derivatives using a dual CuBr/chiral ...
Scheme 14: Aminotrifluoromethylation of an N-alkenylurea derivative using a dual CuBr/phosphoric acid catalyti...
Scheme 15: 1,2-Formyl- and 1,2-cyanotrifluoromethylation of alkenes under photoredox catalysis.
Scheme 16: First simultaneous introduction of the CF3 moiety and a Cl atom onto alkenes.
Scheme 17: Chlorotrifluoromethylaltion of terminal, 1,1- and 1,2-substituted alkenes.
Scheme 18: Chorotrifluoromethylation of electron-deficient alkenes (DCE = dichloroethane).
Scheme 19: Cascade trifluoromethylation/cyclisation/chlorination of N-allyl-N-(benzyloxy)methacrylamide.
Scheme 20: Cascade trifluoromethylation/cyclisation (/chlorination) of diethyl 2-allyl-2-(3-methylbut-2-en-1-y...
Scheme 21: Trifluoromethylchlorosulfonylation of allylbenzene derivatives and aliphatic alkenes.
Scheme 22: Access to β-hydroxysulfones from CF3-containing sulfonyl chlorides through a photocatalytic sequenc...
Scheme 23: Cascade trifluoromethylchlorosulfonylation/cyclisation reaction of alkenols: a route to trifluorome...
Scheme 24: First direct C–H trifluoromethylation of arenes and proposed mechanism.
Scheme 25: Direct C–H trifluoromethylation of five- and six-membered (hetero)arenes under photoredox catalysis....
Scheme 26: Alternative pathway for the C–H trifluoromethylation of (hetero)arenes under photoredox catalysis.
Scheme 27: Direct C–H trifluoromethylation of five- and six-membered ring (hetero)arenes using heterogeneous c...
Scheme 28: Trifluoromethylation of terminal olefins.
Scheme 29: Trifluoromethylation of enamides.
Scheme 30: (E)-Selective trifluoromethylation of β-nitroalkenes under photoredox catalysis.
Scheme 31: Photoredox-catalysed trifluoromethylation/cyclisation of an o-azidoarylalkynes.
Scheme 32: Regio- and stereoselective chlorotrifluoromethylation of alkynes.
Scheme 33: PMe3-mediated trifluoromethylsulfenylation by in situ generation of CF3SCl.
Scheme 34: (EtO)2P(O)H-mediated trifluoromethylsulfenylation of (hetero)arenes and thiols.
Scheme 35: PPh3/NaI-mediated trifluoromethylsulfenylation of indole derivatives.
Scheme 36: PPh3/n-Bu4NI mediated trifluoromethylsulfenylation of thiophenol derivatives.
Scheme 37: PPh3/Et3N mediated trifluoromethylsulfinylation of benzylamine.
Scheme 38: PCy3-mediated trifluoromethylsulfinylation of azaarenes, amines and phenols.
Scheme 39: Mono- and dichlorination of carbon acids.
Scheme 40: Monochlorination of (N-aryl-N-hydroxy)acylacetamides.
Scheme 41: Examples of the synthesis of heterocycles fused with β-lactams through a chlorination/cyclisation p...
Scheme 42: Enantioselective chlorination of β-ketoesters and oxindoles.
Scheme 43: Enantioselective chlorination of 3-acyloxazolidin-2-one derivatives (NMM = N-methylmorpholine).
Synthetic mRNA capping
- Fabian Muttach,
- Nils Muthmann and
- Andrea Rentmeister
Beilstein J. Org. Chem. 2017, 13, 2819–2832, doi:10.3762/bjoc.13.274
Graphical Abstract
Figure 1: Schematic representation of enzymatic 5′-cap formation in eukaryotic mRNA. The 5′-triphosphate-end ...
Figure 2: Nucleotide analogues 1–11 were converted by Paramecium bursaria Chlorella virus-1 capping enzyme in...
Figure 3: Schematic representation of co-transcriptional capping with different cap analogues. A DNA-dependen...
Figure 4: (A) Structures of commercially available mRNA cap analogues. (B) Synthetic route to cap analogues a...
Figure 5: Enzymatic modification of cap analogues at their N2- or N7-position or a combination of both. (A) F...
Figure 6: Synthesis of cap-containing RNA by solid-phase synthesis. (A) A TMG-capped mRNA was synthesized sta...
Figure 7: Click chemistry for the preparation of capped RNA and cap analogues. (A) Preparation of capped RNA ...
The photodecarboxylative addition of carboxylates to phthalimides as a key-step in the synthesis of biologically active 3-arylmethylene-2,3-dihydro-1H-isoindolin-1-ones
- Ommid Anamimoghadam,
- Saira Mumtaz,
- Anke Nietsch,
- Gaetano Saya,
- Cherie A. Motti,
- Jun Wang,
- Peter C. Junk,
- Ashfaq Mahmood Qureshi and
- Michael Oelgemöller
Beilstein J. Org. Chem. 2017, 13, 2833–2841, doi:10.3762/bjoc.13.275
Graphical Abstract
Figure 1: Molecular structures of AL-12, AL-12B and AL-5.
Scheme 1: Retrosynthetic analysis of AL-12, AL-12B and AL-5 (in their neutral forms) and their derivatives.
Scheme 2: Optimization study using phenylacetate 2a.
Scheme 3: Photodecarboxylative additions to N-(bromoalkyl)phthalimides.
Figure 2: Crystal structures of photoaddition products 3a (left) and 3b (right).
Scheme 4: Formation of 5 by photodecarboxylative additions.
Scheme 5: Acid-catalyzed dehydration of 3a–q.
Figure 3: Crystal structure of (E)-7a. Side view and front view.
Scheme 6: Amination of dehydrated products 7a–q.
Figure 4: Crystal structure of (Z)-8a. Side view and front view.
Scheme 7: Mechanistic scenario for the photodecarboxylative addition.
Scheme 8: Possible scenarios for nucleophilic cyclization to 4.
Scheme 9: Possible E/Z isomerization for compounds 8a–y.
The use of 4,4,4-trifluorothreonine to stabilize extended peptide structures and mimic β-strands
- Yaochun Xu,
- Isabelle Correia,
- Tap Ha-Duong,
- Nadjib Kihal,
- Jean-Louis Soulier,
- Julia Kaffy,
- Benoît Crousse,
- Olivier Lequin and
- Sandrine Ongeri
Beilstein J. Org. Chem. 2017, 13, 2842–2853, doi:10.3762/bjoc.13.276
Graphical Abstract
Figure 1: A) Natural threonine and its trifluoromethyl analogues sawhorse projections. B) Structure of Boc-pr...
Scheme 1: Synthesis of (2S,3R)-Boc-CF3-Thr(Bzl) 9.
Scheme 2: Synthesis of (2S,3S)-Boc-CF3-Thr 14.
Scheme 3: Synthesis of pentapeptides 1a–4a and 1b–4b.
Figure 2: Probability distribution of the peptide conformations as a function of end-to-end distance (defined...
Figure 3: Probability distribution of the peptide dihedral angles ψ for the three central residues Val2 (blac...
Figure 4: Effects of compounds 1–4 on Aβ1-42 fibrillization assessed by ThT-fluorescence spectroscopy at 10:1...
Nucleophilic dearomatization of 4-aza-6-nitrobenzofuroxan by CH acids in the synthesis of pharmacology-oriented compounds
- Alexey M. Starosotnikov,
- Dmitry V. Shkaev,
- Maxim A. Bastrakov,
- Ivan V. Fedyanin,
- Svyatoslav A. Shevelev and
- Igor L. Dalinger
Beilstein J. Org. Chem. 2017, 13, 2854–2861, doi:10.3762/bjoc.13.277
Graphical Abstract
Scheme 1: Beirut reaction.
Scheme 2: Reactivity of 4,6-dinitrobenzofuroxan.
Scheme 3: Reactivity of ANBF (1).
Scheme 4: Synthesis of ANBF.
Scheme 5: Reactions of ANBF with β-dicarbonyl compounds.
Figure 1: General view of molecule 12 in crystal. Anisotropic displacement parameters for non-hydrogen atoms ...
Scheme 6: Reaction of ANBF with 2,4,6-trinitrotoluene.
Figure 2: Partial 1H NMR spectrum of compound 15 in DMSO-d6.
Figure 3: General view of molecule 15 in crystal. Anisotropic displacement parameters for non-hydrogen atoms ...
Scheme 7: Plausible mechanism of adducts formation.
Reactivity of bromoselenophenes in palladium-catalyzed direct arylations
- Aymen Skhiri,
- Ridha Ben Salem,
- Jean-François Soulé and
- Henri Doucet
Beilstein J. Org. Chem. 2017, 13, 2862–2868, doi:10.3762/bjoc.13.278
Graphical Abstract
Scheme 1: Reported Pd-catalyzed heteroarylations of bromoselenophenes.
Scheme 2: Palladium-catalyzed heteroarylations of 2-bromoselenophene. *: 110 °C
Scheme 3: Palladium-catalyzed 2,5-diheteroarylation of 2,5-dibromoselenophene.
Scheme 4: Synthesis of 2-aryl-5-(heteroaryl)selenophenes.
Scheme 5: Proposed catalytic cycle.
Position-dependent impact of hexafluoroleucine and trifluoroisoleucine on protease digestion
- Susanne Huhmann,
- Anne-Katrin Stegemann,
- Kristin Folmert,
- Damian Klemczak,
- Johann Moschner,
- Michelle Kube and
- Beate Koksch
Beilstein J. Org. Chem. 2017, 13, 2869–2882, doi:10.3762/bjoc.13.279
Graphical Abstract
Figure 1: (a) Structures of isoleucine (1), leucine (2), and their fluorinated analogues 5,5,5-trifluoroisole...
Figure 2: Percentage of substrate remaining after incubation for 120 min (left) and 24 h (right) with α-chymo...
Figure 3: Cleavage positions observed in the digestion of library peptides with α-chymotrypsin.
Figure 4: Percentage of substrate remaining after incubation for 120 min (left) and 24 h (right) with pepsin ...
Figure 5: Cleavage positions for digestion of the different peptides with pepsin.
Figure 6: Percentage of substrate remaining after incubation for 120 min (left) and 24 h (right) with elastas...
Figure 7: Cleavage positions for digestion of the different peptides with elastase.
Figure 8: Percentage of substrate remaining after incubation for 120 min (left) and 24 h (right) with protein...
Figure 9: Cleavage positions found with proteinase K.
Figure 10: Dimension of stabilization or destabilization upon TfIle or HfLeu incorporation compared to the non...
The synthesis of the 2,3-difluorobutan-1,4-diol diastereomers
- Robert Szpera,
- Nadia Kovalenko,
- Kalaiselvi Natarajan,
- Nina Paillard and
- Bruno Linclau
Beilstein J. Org. Chem. 2017, 13, 2883–2887, doi:10.3762/bjoc.13.280
Graphical Abstract
Scheme 1: The synthesis of anti-2,3-difluorobutan-1,4-diol (anti-5) [17].
Scheme 2: Improved epoxide opening and deoxofluorination conditions.
Scheme 3: Attempted synthesis of anti-5 via acetonide protection.
Scheme 4: Completion of the synthesis of anti-5.
Scheme 5: Synthesis of (±)-syn-5.
Acid-catalyzed ring-opening reactions of a cyclopropanated 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with alcohols
- Katrina Tait,
- Alysia Horvath,
- Nicolas Blanchard and
- William Tam
Beilstein J. Org. Chem. 2017, 13, 2888–2894, doi:10.3762/bjoc.13.281
Graphical Abstract
Scheme 1: General reaction pathways for 3-aza-2-oxabicyclic alkenes.
Scheme 2: Various reactions involving modification of the alkene component of 3-aza-2-oxabicyclic alkenes.
Scheme 3: Various reactions involving cleavage of the C–O bond of 3-aza-2-oxabicyclic alkenes.
Scheme 4: Ring-opening reactions of cyclopropanated 3-aza-2-oxabicyclic alkenes.
Scheme 5: Different possible ring-opening pathways of cyclopropanated 3-aza-2-oxabicyclic alkenes.
Scheme 6: Possible mechanisms for the nucleophilic ring-opening of cyclopropanated 3-aza-2-oxabicyclic alkene ...
Quinone-catalyzed oxidative deformylation: synthesis of imines from amino alcohols
- Xinyun Liu,
- Johnny H. Phan,
- Benjamin J. Haugeberg,
- Shrikant S. Londhe and
- Michael D. Clift
Beilstein J. Org. Chem. 2017, 13, 2895–2901, doi:10.3762/bjoc.13.282
Graphical Abstract
Scheme 1: Established methods for the preparation of imines vs this work.
Scheme 2: Proposed catalytic cycle for quinone-catalyzed deformylation.
Scheme 3: Studies of quinone-catalyzed C−C bond cleavage in related substrates.
Scheme 4: Sequential oxidative deformylation/Mukaiyama−Mannich addition using phenylglycinol.
Halogen-containing thiazole orange analogues – new fluorogenic DNA stains
- Aleksey A. Vasilev,
- Meglena I. Kandinska,
- Stanimir S. Stoyanov,
- Stanislava B. Yordanova,
- David Sucunza,
- Juan J. Vaquero,
- Obis D. Castaño,
- Stanislav Baluschev and
- Silvia E. Angelova
Beilstein J. Org. Chem. 2017, 13, 2902–2914, doi:10.3762/bjoc.13.283
Graphical Abstract
Scheme 1: Chemical structures of TO and SYBR Green I – commercial monomethine fluorescent dsDNA binders.
Scheme 2: Synthesis of the monofluoro-substituted dye TO-1F. Reagents, conditions and yields: (i) sodium meth...
Scheme 3: Synthesis of new halogen-containing analogues of TO. Reagents, conditions and yields: (i) DMS, 100 ...
Figure 1: Absorption spectra of the studied compounds in MeOH (c = 1 × 10−5 M).
Figure 2: Absorption spectra of dye 5b (c = 5 × 10−7 M) in TE buffer, in the absence and presence of dsDNA (c...
Figure 3: Fluorescence spectra of dye 5a (c = 5 × 10–7 M) in TE buffer and in the presence of increasing conc...
Figure 4: Photostability of dyes TO-7Cl and 5a–d in acetonitrile in the concentration range of 1 × 10−5 M.
Figure 5: B3LYP optimized structures.
Figure 6: Graphical representation of the frontier orbitals (isodensity plot, isovalue = 0.02 a.u.).
Figure 7: Simulated TDPBE0 spectra in methanol.
Figure 8: Electron density (isovalue = 0.002) mapped with electrostatic potential (color scheme: green for ne...
Conformational preferences of α-fluoroketones may influence their reactivity
- Graham Pattison
Beilstein J. Org. Chem. 2017, 13, 2915–2921, doi:10.3762/bjoc.13.284
Graphical Abstract
Scheme 1: Relative reactivity of α-fluoroacetophenone to α-chloroacetophenone and α-bromoacetophenone.
Scheme 2: Competitive reduction of haloacetophenones and acetophenone.
Figure 1: Conformational energy profiles of halogenated acetophenones (a) in gas phase; (b) in EtOH; (c) over...
Figure 2: Optimised gas phase geometries of (a) α-fluoroacetophenone and (b) α-chloroacetophenone emphasising...
Figure 3: Most stable conformations of (a) α-fluoroacetophenone and (b) α-chloroacetophenone in ethanol.
Figure 4: Expected reactive conformation of halo-acetophenones.
Figure 5: Orbital interactions in gauche- and cis-conformations of haloacetophenones.
Figure 6: Variation of dipole moment with angle for haloacetophenones.
Figure 7: Highest energy conformation of fluoroacetophenone, emphasizing the closeness of approach of fluorin...
Scheme 3: Competitive reduction of fluoroacetone and chloroacetone.
Figure 8: Conformational energy profiles of halogenated acetones in gas phase and in MeOH.
Figure 9: Overlay of conformational energy profiles of fluoroacetone and fluoroacetophenone.
Microfluidic radiosynthesis of [18F]FEMPT, a high affinity PET radiotracer for imaging serotonin receptors
- Thomas Lee Collier,
- Steven H. Liang,
- J. John Mann,
- Neil Vasdev and
- J. S. Dileep Kumar
Beilstein J. Org. Chem. 2017, 13, 2922–2927, doi:10.3762/bjoc.13.285
Graphical Abstract
Figure 1: Representative examples of recent 5-HT1AR agonists [3-9].
Scheme 1: Synthesis of FEMPT (7).
Scheme 2: Radiosynthetic scheme for the microfluidic flow synthesis of [18F]fluoroethyltosylate (10) and [18F...
Figure 2: (A) Incorporation yield of [18F]fluoride versus flow rate, red line 180 °C, blue line 150 °C, moder...
Figure 3: Analysis of the final formulated product by LC–MS, using the trapping system to improve the sensiti...
