Umpolung reactions of C=X bonds(X=O,N)are valuable ways of constructing new C–C bonds,which are sometimes difficult to be constructed using traditional synthetic pathways.Classical polarity inversion of C=X bonds(X=O...Umpolung reactions of C=X bonds(X=O,N)are valuable ways of constructing new C–C bonds,which are sometimes difficult to be constructed using traditional synthetic pathways.Classical polarity inversion of C=X bonds(X=O,N)usually requires air or moisture‐sensitive and strong reducing agents,which limit the feasibility of substrate scope.Herein we describe a photo‐induced reductive cross‐coupling reaction of aldehydes,ketones and imines with electron‐deficient arenes(aromatic nitriles)using fac‐Ir(ppy)3as a photocatalyst and diisopropylethylamine(DIPEA)as a terminal reductant under visible light irradiation.Mild conditions and high yields mean that this new polarity inversion strategy can be used with aryl‐substituted alcohols and amines.Spectroscopic studies and control experiments have demonstrated the oxidative quenching of Ir(ppy)3*by electron‐deficient arenes involved in the key step for the C–C bond formation.展开更多
Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
Palladium-catalyzed coupling of trifluorovinylzinc reagent with substituted aryl halides Y-C_6H_4-X (Y=p-NO_2, p-and m-COOMe, p-COOH, p-CONH_2, p- and m-CN; X=Br, I, Cl) provides a synthetic method for α, β, β-trif...Palladium-catalyzed coupling of trifluorovinylzinc reagent with substituted aryl halides Y-C_6H_4-X (Y=p-NO_2, p-and m-COOMe, p-COOH, p-CONH_2, p- and m-CN; X=Br, I, Cl) provides a synthetic method for α, β, β-trifluorostyrenes(Y-TFS's). A series of previously unavailable Y-TFS's were thus obtained.展开更多
Three kind of aryl-substituted tri-benzyl sulfonium salts [ (4-phX)phSph2 ] PF6 [ X = S, O ] were prepared by the condensation of biphenyl sulfoxide with biphenyl sulfide, biphenyl ether or 1, 1' -biphenyl in the p...Three kind of aryl-substituted tri-benzyl sulfonium salts [ (4-phX)phSph2 ] PF6 [ X = S, O ] were prepared by the condensation of biphenyl sulfoxide with biphenyl sulfide, biphenyl ether or 1, 1' -biphenyl in the presence of polyphosphoric acid which can be used as dehydrate agent. The reaction condition was mild, such as reaction temperature between 40- 50 ℃ ,reactive time 2- 3 h, the yield of 4-(phenylthio)triphenylsulfonium hexafluorophosphate was 87.6%. The three kind sulfonium salts show better curing character to epoxy resin.展开更多
A series of N1-substituted-3-aryl-4-alkyl-4, 5-dihydro-1H-1-pyrazolethiocarboxamide were prepared from the Mannich bases of aryl ketones in good yields. Some derivatives were found to be active against the cysteine p...A series of N1-substituted-3-aryl-4-alkyl-4, 5-dihydro-1H-1-pyrazolethiocarboxamide were prepared from the Mannich bases of aryl ketones in good yields. Some derivatives were found to be active against the cysteine protease of T.cruzi..展开更多
A phosphrous-containing poly(aryl ether ketone) was synthesized derived from bisphenol-A and bis[4-(4- fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) by nucleophilic substitution reaction. The structure of...A phosphrous-containing poly(aryl ether ketone) was synthesized derived from bisphenol-A and bis[4-(4- fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature (Tg) of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer's CH2Cl2 solution. The limiting oxygen index (LOI) of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.展开更多
The direct arylation of substituted pyridines with several arylboronic acids has been developed.This transformation could proceed readily at ambient temperature using inexpensive reagents:iron(Ⅱ)oxalate as a catalyst...The direct arylation of substituted pyridines with several arylboronic acids has been developed.This transformation could proceed readily at ambient temperature using inexpensive reagents:iron(Ⅱ)oxalate as a catalyst,potassium persulfate as a co-oxidant,which can afford the arylated products in mild to good yields.The mechanism is presumed to proceed through a nucleophilic radical addition to the pyridines with in situ reoxidation.展开更多
A novel triphenylphosphine-contained poly(ether ether ketone ketone) was synthesized from bis[4-(p-fluorobenzoyl)-phenyl]phenylphosphine oxide and hydroquinone by nucleophilic copolycondensation with sulfolane as the ...A novel triphenylphosphine-contained poly(ether ether ketone ketone) was synthesized from bis[4-(p-fluorobenzoyl)-phenyl]phenylphosphine oxide and hydroquinone by nucleophilic copolycondensation with sulfolane as the solvent. The structure was confirmed via FTIR, 31P NMR and 1H NMR. Electrical property, mechanical property, heat-resistance property, flame resistance and solubility were also evaluated. The results show that the polymer has an excellent heat-resistance, the glass transition temperature(Tg) is 212.6 ℃. The 5% mass loss of the polymer in nitrogen atmosphere took place at 476 ℃. The polymer is soluble in many organic solvents, such as CH2Cl2, CHCl3, Cl2(CH)2Cl2, Cl(CH2)2Cl, DMF, and NMP at room temperature, the polymer possesses well film ability, good mechanics property, electrical property, and the LOI is 44 which indicates that it possesses an excellent flame retardancy.展开更多
文摘Umpolung reactions of C=X bonds(X=O,N)are valuable ways of constructing new C–C bonds,which are sometimes difficult to be constructed using traditional synthetic pathways.Classical polarity inversion of C=X bonds(X=O,N)usually requires air or moisture‐sensitive and strong reducing agents,which limit the feasibility of substrate scope.Herein we describe a photo‐induced reductive cross‐coupling reaction of aldehydes,ketones and imines with electron‐deficient arenes(aromatic nitriles)using fac‐Ir(ppy)3as a photocatalyst and diisopropylethylamine(DIPEA)as a terminal reductant under visible light irradiation.Mild conditions and high yields mean that this new polarity inversion strategy can be used with aryl‐substituted alcohols and amines.Spectroscopic studies and control experiments have demonstrated the oxidative quenching of Ir(ppy)3*by electron‐deficient arenes involved in the key step for the C–C bond formation.
文摘Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
基金Supported by National Natural Science Foundation of China
文摘Palladium-catalyzed coupling of trifluorovinylzinc reagent with substituted aryl halides Y-C_6H_4-X (Y=p-NO_2, p-and m-COOMe, p-COOH, p-CONH_2, p- and m-CN; X=Br, I, Cl) provides a synthetic method for α, β, β-trifluorostyrenes(Y-TFS's). A series of previously unavailable Y-TFS's were thus obtained.
文摘Three kind of aryl-substituted tri-benzyl sulfonium salts [ (4-phX)phSph2 ] PF6 [ X = S, O ] were prepared by the condensation of biphenyl sulfoxide with biphenyl sulfide, biphenyl ether or 1, 1' -biphenyl in the presence of polyphosphoric acid which can be used as dehydrate agent. The reaction condition was mild, such as reaction temperature between 40- 50 ℃ ,reactive time 2- 3 h, the yield of 4-(phenylthio)triphenylsulfonium hexafluorophosphate was 87.6%. The three kind sulfonium salts show better curing character to epoxy resin.
文摘A series of N1-substituted-3-aryl-4-alkyl-4, 5-dihydro-1H-1-pyrazolethiocarboxamide were prepared from the Mannich bases of aryl ketones in good yields. Some derivatives were found to be active against the cysteine protease of T.cruzi..
基金This work was supported by the National Natural Science Foundation of China(No.50203008).
文摘A phosphrous-containing poly(aryl ether ketone) was synthesized derived from bisphenol-A and bis[4-(4- fluorobenzoyl)phenyl] phenyl phosphine oxide (FPPPO) by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature (Tg) of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer's CH2Cl2 solution. The limiting oxygen index (LOI) of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.
基金We are thankful for the financial support of“National Natural Science Foundation of China(21302014)”“Program of Applied Basic Research in Changzhou(CJ20130003)”“Open Project of Jiangsu Province Key Laboratory of Fine Petrochemical Engineering(KF1304)”.
文摘The direct arylation of substituted pyridines with several arylboronic acids has been developed.This transformation could proceed readily at ambient temperature using inexpensive reagents:iron(Ⅱ)oxalate as a catalyst,potassium persulfate as a co-oxidant,which can afford the arylated products in mild to good yields.The mechanism is presumed to proceed through a nucleophilic radical addition to the pyridines with in situ reoxidation.
文摘A novel triphenylphosphine-contained poly(ether ether ketone ketone) was synthesized from bis[4-(p-fluorobenzoyl)-phenyl]phenylphosphine oxide and hydroquinone by nucleophilic copolycondensation with sulfolane as the solvent. The structure was confirmed via FTIR, 31P NMR and 1H NMR. Electrical property, mechanical property, heat-resistance property, flame resistance and solubility were also evaluated. The results show that the polymer has an excellent heat-resistance, the glass transition temperature(Tg) is 212.6 ℃. The 5% mass loss of the polymer in nitrogen atmosphere took place at 476 ℃. The polymer is soluble in many organic solvents, such as CH2Cl2, CHCl3, Cl2(CH)2Cl2, Cl(CH2)2Cl, DMF, and NMP at room temperature, the polymer possesses well film ability, good mechanics property, electrical property, and the LOI is 44 which indicates that it possesses an excellent flame retardancy.