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Mingwu Ding - One of the best experts on this subject based on the ideXlab platform.
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facile synthesis of 3 arylidene 3h 1 4 benzodiazepines by a sequential ugi staudinger aza wittig Reaction
Synthesis, 2016Co-Authors: Mingwu DingAbstract:N -[2-(Alkylamino)-1-(2-azidophenyl)-2-oxoethyl]- N -(3-oxoprop-1-en-2-yl)amides, obtained from the Ugi Reaction of a vinyliminophosphorane, 2-azidobenzaldehyde, a carboxylic acid, and an alkyl isocyanide, reacted with triphenylphosphine to give various 3-arylidene-3 H -1,4-benzodiazepine in good yields via sequential Staudinger and intramolecular Aza-Wittig Reaction.
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catalytic aza wittig Reaction of acid anhydride for the synthesis of 4h benzo d 1 3 oxazin 4 ones and 4 benzylidene 2 aryloxazol 5 4h ones
ACS Catalysis, 2016Co-Authors: Long Wang, Ming Guo Liu, Yibi Xie, Nianyu Huang, Jiaying Yan, Mingwu DingAbstract:Compared to the Aza-Wittig Reaction of aldehydes, ketones, amides, and esters, the Aza-Wittig Reaction of acid anhydride was always overlooked, which should be an important part of Wittig Reactions. Here, the Aza-Wittig Reaction of anhydride and catalytic Aza-Wittig Reaction of anhydride were both developed with high yields, which provides an efficient method to synthesize of 4H-benzo[d][1,3]oxazin-4-ones and 4-benzylidene-2-aryloxazol-5(4H)-ones. The strategy of copper-catalyzed reduction of phosphine oxide was used and found effective for this transformation. Additionally, the one-pot catalytic Aza-Wittig Reaction of carboxylic acids was achieved. Furthermore, NMR experiments and Hammett plot recorded the process of catalytic Aza-Wittig Reaction of anhydride, which provides direct proof that the copper-catalyzed reduction of waste phosphine oxide is the key step in this transformation.
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One-Pot Synthesis of Multisubstituted Benzimidazoles via Sequential Ugi and Catalytic Aza-Wittig Reaction Starting from 2-Aminobenzoyl Azides
The Journal of organic chemistry, 2016Co-Authors: Yan-mei Yan, Yong Rao, Mingwu DingAbstract:A simple and one-pot synthesis of multisubstituted benzimidazoles by a Ugi 4CC/catalytic Aza-Wittig sequence was developed. The Reaction of 2-aminobenzoyl azide 2, aldehyde 3, acid 4, and isocyanide 5 produced the benzimidazoles 8 in moderate to good yields via a sequential Ugi condensation and catalytic Aza-Wittig in the presence of a catalytic amount of phospholene oxide.
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One-Pot Synthesis of Multisubstituted Benzimidazoles via Sequential Ugi and Catalytic Aza-Wittig Reaction Starting from 2‑Aminobenzoyl Azides
2016Co-Authors: Yan-mei Yan, Yong Rao, Mingwu DingAbstract:A simple and one-pot synthesis of multisubstituted benzimidazoles by a Ugi 4CC/catalytic Aza-Wittig sequence was developed. The Reaction of 2-aminobenzoyl azide 2, aldehyde 3, acid 4, and isocyanide 5 produced the benzimidazoles 8 in moderate to good yields via a sequential Ugi condensation and catalytic Aza-Wittig in the presence of a catalytic amount of phospholene oxide
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new efficient synthesis of 1 4 benzodiazepin 5 ones by catalytic aza wittig Reaction
Synthesis, 2015Co-Authors: Long Wang, Ruqing Qin, Hongye Yan, Mingwu DingAbstract:1,4-Benzodiazepin-5-ones were synthesized in 71–89% yields from 2-isocyanato-N-(2-oxoalkyl)benzamides via a new catalytic intramolecular Aza-Wittig Reaction. Starting from easily accessible phthalic anhydride and α-arylamino ketones, the corresponding 2-{[(2-oxoalkyl)amino]carbonyl}benzoic acids underwent sequential formation of the acid azide and Curtis rearrangement to give 2-isocyanato-N-(2-oxoalkyl)benzamides that were reacted directly to give the final 2,4-diaryl-3,4-dihydro-5H-1,4-benzodiazepin-5-ones and 4-aryl-2-tert-butyl-3,4-dihydro-5H-1,4-benzodiazepin-5-ones.
Gloria Rubiales - One of the best experts on this subject based on the ideXlab platform.
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the aza wittig Reaction an efficient tool for the construction of carbon nitrogen double bonds
Tetrahedron, 2007Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Domitila Aparicio, Jesus M De Los SantosAbstract:Abstract Recent advances in the Aza-Wittig Reaction of phosphazene derivatives with several carbonyl compounds are reviewed. Phosphazenes afford inter- and intramolecular Aza-Wittig Reactions with different compounds such as aldehydes, ketones, esters, thioesters, amides, anhydrides and sulfimides. One of the most important applications of this Reaction is the synthesis of a wide range of acyclic and heterocyclic compounds, ranging from simple monocyclic compounds to complex polycyclic and macrocyclic systems.
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Reaction of n vinylic phosphazenes with α β unsaturated aldehydes azatriene mediated synthesis of dihydropyridines and pyridines derived from β amino acids
Journal of Organic Chemistry, 2006Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Esther Herran, Begona Lecea, Mirari Ayerbe, Fernando P CossioAbstract:Aza-Wittig Reaction of N-vinylic phosphazenes (1,2 addition), derived from diphenylmethylphosphine or derived from trimethylphosphine with alpha,beta-unsaturated aldehydes, leads to the formation of 3-azatrienes through a [2 + 2]-cycloaddition-cycloreversion sequence. The presence of an alkyl substituent in position 3 of N-vinylic phosphazenes increases the steric interactions, and [4 + 2] periselectivity (1,4 addition) is observed. Reaction of azatrienes with alpha,beta-unsaturated aldehydes yields pyridines.
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mechanism and stereoselectivity of the aza wittig Reaction between phosphazenes and aldehydes
Journal of Organic Chemistry, 2006Co-Authors: Fernando P Cossio, Concepcion Alonso, Gloria Rubiales, Begona Lecea, Mirari Ayerbe, Francisco PalaciosAbstract:The mechanism of the Aza-Wittig Reaction between phosphazenes and aldehydes has been studied computationally, using DFT methods (B3LYP/6-31G* level), and experimentally. It has been found that the Reaction consists of a tandem [2+2] cycloaddition−cycloreversion sequence in which π and σ orbitals as well as lone pairs are involved. Both [2+2] processes take place via thermally allowed supra-supra mechanisms. P-trimethyl-λ5-phosphazenes are predicted to be more reactive than their P-triphenyl analogues. The stereochemical outcome of the whole Reaction depends only on the second step, because conformational changes in the intermediate 1,3,2-λ5-oxazaphosphazetidines have a much lower activation energy than the second [2+2] cycloreversion Reaction. Preferential or exclusive formation of the corresponding (E)-imines is predicted.
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aza wittig Reaction of fluoroalkylated n vinylic phosphazenes with carbonyl compounds usefulness of 2 azadienes for the preparation of fluoroalkyl pyridine derivatives
Tetrahedron, 2005Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Maite VillegasAbstract:Abstract A method for the preparation of 3-fluoroalkyl substituted 2-aza-butadienes 6 by Aza-Wittig Reaction of 3-fluoroalkyl- N -vinylic phosphazenes 4 and aldehydes 5 is reported. [4+2] Cycloaddition Reaction of these heterodienes 6 with enamines 9 gives fluoroalkyl substituted pyridine 15 , 16 , 24 – 27 and isoquinoline 12 – 14 , 20 derivatives.
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Reaction of n vinylic phosphazenes derived from β amino acids with aldehydes azadiene mediated synthesis of dihydropyridines pyridines and polycyclic nitrogen derivatives
Journal of Organic Chemistry, 1999Co-Authors: Francisco Palacios, Esther Herran, Gloria RubialesAbstract:Enamino phosphonium salts 2 are obtained by 1,2-addition of hydrogen chloride to N-vinylic phosphazenes 1 derived from triphenylphosphine. Aza-Wittig Reaction of phosphazenes 1 derived from triphenylphosphine and 6 derived from diphenylmethylphosphine with aldehydes 3 leads to the formation of 2-azadienes 7. Reaction of azadienes 7 with enamines affords dihydropyridines 9 and 11, pyridines 12, and bicyclic nitrogen heterocycles 15−18 in a regioselective fashion, while heterodiene 20 reacts in the same way with pyrrolidinocyclohexanone giving 1-azaphenanthrene compound 21. Reaction of enamino phosphonium salts 2 with aldehydes 3 gives symmetrical dihydropyridines 5.
Francisco Palacios - One of the best experts on this subject based on the ideXlab platform.
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the aza wittig Reaction an efficient tool for the construction of carbon nitrogen double bonds
Tetrahedron, 2007Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Domitila Aparicio, Jesus M De Los SantosAbstract:Abstract Recent advances in the Aza-Wittig Reaction of phosphazene derivatives with several carbonyl compounds are reviewed. Phosphazenes afford inter- and intramolecular Aza-Wittig Reactions with different compounds such as aldehydes, ketones, esters, thioesters, amides, anhydrides and sulfimides. One of the most important applications of this Reaction is the synthesis of a wide range of acyclic and heterocyclic compounds, ranging from simple monocyclic compounds to complex polycyclic and macrocyclic systems.
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Reaction of n vinylic phosphazenes with α β unsaturated aldehydes azatriene mediated synthesis of dihydropyridines and pyridines derived from β amino acids
Journal of Organic Chemistry, 2006Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Esther Herran, Begona Lecea, Mirari Ayerbe, Fernando P CossioAbstract:Aza-Wittig Reaction of N-vinylic phosphazenes (1,2 addition), derived from diphenylmethylphosphine or derived from trimethylphosphine with alpha,beta-unsaturated aldehydes, leads to the formation of 3-azatrienes through a [2 + 2]-cycloaddition-cycloreversion sequence. The presence of an alkyl substituent in position 3 of N-vinylic phosphazenes increases the steric interactions, and [4 + 2] periselectivity (1,4 addition) is observed. Reaction of azatrienes with alpha,beta-unsaturated aldehydes yields pyridines.
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mechanism and stereoselectivity of the aza wittig Reaction between phosphazenes and aldehydes
Journal of Organic Chemistry, 2006Co-Authors: Fernando P Cossio, Concepcion Alonso, Gloria Rubiales, Begona Lecea, Mirari Ayerbe, Francisco PalaciosAbstract:The mechanism of the Aza-Wittig Reaction between phosphazenes and aldehydes has been studied computationally, using DFT methods (B3LYP/6-31G* level), and experimentally. It has been found that the Reaction consists of a tandem [2+2] cycloaddition−cycloreversion sequence in which π and σ orbitals as well as lone pairs are involved. Both [2+2] processes take place via thermally allowed supra-supra mechanisms. P-trimethyl-λ5-phosphazenes are predicted to be more reactive than their P-triphenyl analogues. The stereochemical outcome of the whole Reaction depends only on the second step, because conformational changes in the intermediate 1,3,2-λ5-oxazaphosphazetidines have a much lower activation energy than the second [2+2] cycloreversion Reaction. Preferential or exclusive formation of the corresponding (E)-imines is predicted.
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aza wittig Reaction of fluoroalkylated n vinylic phosphazenes with carbonyl compounds usefulness of 2 azadienes for the preparation of fluoroalkyl pyridine derivatives
Tetrahedron, 2005Co-Authors: Francisco Palacios, Concepcion Alonso, Gloria Rubiales, Maite VillegasAbstract:Abstract A method for the preparation of 3-fluoroalkyl substituted 2-aza-butadienes 6 by Aza-Wittig Reaction of 3-fluoroalkyl- N -vinylic phosphazenes 4 and aldehydes 5 is reported. [4+2] Cycloaddition Reaction of these heterodienes 6 with enamines 9 gives fluoroalkyl substituted pyridine 15 , 16 , 24 – 27 and isoquinoline 12 – 14 , 20 derivatives.
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aza wittig Reaction of n phosphorylalkyl phosphazenes with carbonyl compounds and phenylisocyanate synthesis of 4 amino 3 phosphoryl 2 azadienes and pyrazine phosphonates
ChemInform, 2003Co-Authors: Francisco Palacios, Ana Ochoa M De Retana, Eduardo Martinez De Marigorta, Marta Rodriguez, Jaione PagaldayAbstract:Abstract Simple and functionalized N-phosphorylalkyl imines and N-phosphorylalkyl-N′-phenyl-carbodiimides are obtained by Aza-Wittig Reaction of phosphazenes derived from aminophosphonates with carbonyl compounds and phenyl isocyanate. The Reaction with dimethylformamide diethyl acetal (DMF–DEA) of these functionalized imines leads to the synthesis of 4-amino-3-phosphoryl-2-azadienes. N-Phosphorylmethyl imine derived from benzaldehyde can be used for the preparation of substituted pyrrole-phosphonates, while acid treatment of 4-dimethylamino-3-diethylphosphoryl-1-phenyl-2-azadiene gives diethyl 5-diethylphosphorylpyrazin-2-ylphosphonate.
Anatoly D Shutalev - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of γ‑Azido-β-ureido Ketones and Their Transformation into Functionalized Pyrrolines and Pyrroles via Staudinger/Aza-Wittig Reaction
2016Co-Authors: Anastasia A. Fesenko, Anatoly D ShutalevAbstract:A simple two-step procedure yielding γ-azido-β-ureido ketones or/and their cyclic isomers, 6-(1-azidoalkyl)-4-hydroxyhexahydropyrimidin-2-ones, has been developed. The synthesis includes three-component condensation of acetals of 2-azidoaldehydes with urea or methylurea and p-toluenesulfinic acid in aqueous formic acid followed by Reaction of the obtained N-[(2-azido-1-tosyl)alkyl]ureas with sodium enolates of α-functionalized ketones. The azido ketones or their cyclic isomers are transformed into ureido-substituted Δ1- or/and Δ2-pyrrolines via Staudinger/Aza-Wittig Reaction promoted by PPh3. The obtained pyrrolines are converted into 3-functionalized 1H-pyrroles via elimination of urea under acidic conditions. Convenient one-pot syntheses of 1H-pyrroles starting from N-[(2-azido-1-tosyl)alkyl]ureas or γ-azido-β-ureido ketones have been also developed
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a novel access to pyrido 4 3 d pyrimidine scaffold via staudinger intramolecular aza wittig Reaction of 5 acyl 4 β azidoalkyl 1 2 3 4 tetrahydropyrimidin 2 ones
ChemInform, 2015Co-Authors: Anastasia A Fesenko, Anatoly D ShutalevAbstract:The general four-step approach for the synthesis of pyridopyrimidine derivatives involves a final intramolecular Staudinger/Aza-Wittig Reaction as the key step.
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a novel access to pyrido 4 3 d pyrimidine scaffold via staudinger intramolecular aza wittig Reaction of 5 acyl 4 β azidoalkyl 1 2 3 4 tetrahydropyrimidin 2 ones
Tetrahedron, 2014Co-Authors: Anastasia A Fesenko, Anatoly D ShutalevAbstract:A general four-step approach to 1,2,3,7,8,8a-hexahydropyrido[4,3-d]pyrimidin-2-ones via Staudinger/intramolecular Aza-Wittig Reaction of 5-acyl-4-(β-azidoalkyl)-1,2,3,4-tetrahydropyrimidin-2-ones promoted by PPh3 was developed. Synthesis of the starting pyrimidinones included preparation of 3-azidoaldehydes by the addition of hydrazoic acid to α,β-unsaturated aldehydes, transformation of 3-azidoaldehydes into N-[(3-azido-1-tosyl)alkyl]ureas followed by the Reaction with enolates of dibenzoylmethane, benzoylacetone, acetylacetone, or ethyl 2,4-dioxo-4-phenylbutanoate and dehydration of the resulting products under acidic conditions.
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a selective synthesis of β isothiocyanato ketones through a staudinger aza wittig Reaction of β azido ketones
ChemInform, 2013Co-Authors: Anastasia A Fesenko, Ekaterina A Demyachenko, Galina A Fedorova, Anatoly D ShutalevAbstract:Three β-isothiocyanato ketones (III) are synthesized by Reaction of β-azido ketones and CS2.
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synthesis of γ azido β ureido ketones and their transformation into functionalized pyrrolines and pyrroles via staudinger aza wittig Reaction
ChemInform, 2013Co-Authors: Anastasia A Fesenko, Anatoly D ShutalevAbstract:Hydrolysis of acetals of type (I) and (XII) followed by treatment with the sulfinic acid (III), α-functionalized ketones, and urea or urea derivatives allows a simple and efficient access to γ-azido-β-ureido ketones and/or their cyclic isomers.
Anastasia A Fesenko - One of the best experts on this subject based on the ideXlab platform.
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a novel access to pyrido 4 3 d pyrimidine scaffold via staudinger intramolecular aza wittig Reaction of 5 acyl 4 β azidoalkyl 1 2 3 4 tetrahydropyrimidin 2 ones
ChemInform, 2015Co-Authors: Anastasia A Fesenko, Anatoly D ShutalevAbstract:The general four-step approach for the synthesis of pyridopyrimidine derivatives involves a final intramolecular Staudinger/Aza-Wittig Reaction as the key step.
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a novel access to pyrido 4 3 d pyrimidine scaffold via staudinger intramolecular aza wittig Reaction of 5 acyl 4 β azidoalkyl 1 2 3 4 tetrahydropyrimidin 2 ones
Tetrahedron, 2014Co-Authors: Anastasia A Fesenko, Anatoly D ShutalevAbstract:A general four-step approach to 1,2,3,7,8,8a-hexahydropyrido[4,3-d]pyrimidin-2-ones via Staudinger/intramolecular Aza-Wittig Reaction of 5-acyl-4-(β-azidoalkyl)-1,2,3,4-tetrahydropyrimidin-2-ones promoted by PPh3 was developed. Synthesis of the starting pyrimidinones included preparation of 3-azidoaldehydes by the addition of hydrazoic acid to α,β-unsaturated aldehydes, transformation of 3-azidoaldehydes into N-[(3-azido-1-tosyl)alkyl]ureas followed by the Reaction with enolates of dibenzoylmethane, benzoylacetone, acetylacetone, or ethyl 2,4-dioxo-4-phenylbutanoate and dehydration of the resulting products under acidic conditions.
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a selective synthesis of β isothiocyanato ketones through a staudinger aza wittig Reaction of β azido ketones
ChemInform, 2013Co-Authors: Anastasia A Fesenko, Ekaterina A Demyachenko, Galina A Fedorova, Anatoly D ShutalevAbstract:Three β-isothiocyanato ketones (III) are synthesized by Reaction of β-azido ketones and CS2.
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synthesis of γ azido β ureido ketones and their transformation into functionalized pyrrolines and pyrroles via staudinger aza wittig Reaction
ChemInform, 2013Co-Authors: Anastasia A Fesenko, Anatoly D ShutalevAbstract:Hydrolysis of acetals of type (I) and (XII) followed by treatment with the sulfinic acid (III), α-functionalized ketones, and urea or urea derivatives allows a simple and efficient access to γ-azido-β-ureido ketones and/or their cyclic isomers.
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a selective synthesis of β isothiocyanato ketones through a staudinger aza wittig Reaction of β azido ketones
Monatshefte Fur Chemie, 2013Co-Authors: Anastasia A Fesenko, Ekaterina A Demyachenko, Galina A Fedorova, Anatoly D ShutalevAbstract:A novel selective two-step synthesis of β-isothiocyanato ketones from α,β-unsaturated ketones has been developed. The synthesis includes preparation of β-azido ketones followed by Reaction with triphenylphosphine and carbon disulfide. Treatment of the obtained β-isothiocyanato ketones with ammonia or methylamine gives corresponding hexahydro-4-hydroxypyrimidine-2-thiones. The latter are also prepared directly from β-azido ketones without isolation of the intermediate β-isothiocyanato ketones.
