In the synthesis of l-phenyl-5-substituted amino-4-pyrazole N-alkyl amide, it was found for the first time that one of the two aromatic amido groups in the molecule of 1-phenyl-5-benzoyl amino-4-pyrazole N-alkyl amide...In the synthesis of l-phenyl-5-substituted amino-4-pyrazole N-alkyl amide, it was found for the first time that one of the two aromatic amido groups in the molecule of 1-phenyl-5-benzoyl amino-4-pyrazole N-alkyl amide was reduced selectively by LiAlH_4. new conclusion was drawn after several experiments have been done that ortho-amino(or substituted amino)aryl amide or the aryl amide with its ortho substituent which can be reduced into an amino group(or substituted amino group)can not be reduced by LiAlH_4. It was further rationalized by quantum chemical calculation.展开更多
The reduction of carboxamides into high value-added amines is a very interesting but great challenging topic.Herein we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient ca...The reduction of carboxamides into high value-added amines is a very interesting but great challenging topic.Herein we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient catalyst to reduce primary and secondary carboxamides to amines with excellent yield of 71%-98%and broad substrates scope.The methodology can extend to the gram-scale synthesis of phenethylamine drug with 93%yield.Based on the isolation and characterization of catalytic intermediates,a catalytic mechanism involving multipath reaction is proposed.This work provides efficient lanthanide cluster catalysts for the reduction of carboxamides to amines.展开更多
The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild condition...The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild conditions.The reaction shows high chemoselectivity,tolerating halide,phenolyl,alkenyl,nitro,nitrile,ester,azido,ketone,and enone functional groups.For unsubstituted cyclohexanone carboxamide,two variations were established to achieve either catalytic concomitant reduction of the two carbonyl groups or selective reduction of the amide carbonyl.The protocol was applied to the efficient synthesis and latestage modification of several pharmaceuticals and derivatives.Importantly,we showed that by simply prolonging reaction time to 24–28 h,the reaction can reach an exceptionally high efficiency with turnover number(TON)up to 9.8×10^(6) and turnover frequency(TOF)up to 408,333 at a quite low catalyst loading of 0.00001 mol%(S/C(Ir)=10,000,000).展开更多
Nanoclusters with a precise number of atoms may exhibit unique and often unexpected catalytic properties.Here,we report an atomically precise Pd3 nanocluster as an efficient catalyst,whose catalytic performance differ...Nanoclusters with a precise number of atoms may exhibit unique and often unexpected catalytic properties.Here,we report an atomically precise Pd3 nanocluster as an efficient catalyst,whose catalytic performance differs remarkably from typical Pd nanoparticle catalysts,with excellent reactivity and selectivity in the one-pot synthesis of benzalaniline from nitrobenzene and benzaldehyde.We anticipate that our work will serve as a starting point for the catalytic applications of these tiny atomically precise nanoclusters in green chemistry for the one-pot syntheses of fine chemicals.展开更多
基金Project supported by National Natural Science Foundation of China.
文摘In the synthesis of l-phenyl-5-substituted amino-4-pyrazole N-alkyl amide, it was found for the first time that one of the two aromatic amido groups in the molecule of 1-phenyl-5-benzoyl amino-4-pyrazole N-alkyl amide was reduced selectively by LiAlH_4. new conclusion was drawn after several experiments have been done that ortho-amino(or substituted amino)aryl amide or the aryl amide with its ortho substituent which can be reduced into an amino group(or substituted amino group)can not be reduced by LiAlH_4. It was further rationalized by quantum chemical calculation.
基金supported by the National Natural Science Foundation of China(92161104,21871224,92161203,21721001)。
文摘The reduction of carboxamides into high value-added amines is a very interesting but great challenging topic.Herein we demonstrate that polynuclear lanthanide-oxo clusters Ln16(Ln=Eu and Gd)can be used as efficient catalyst to reduce primary and secondary carboxamides to amines with excellent yield of 71%-98%and broad substrates scope.The methodology can extend to the gram-scale synthesis of phenethylamine drug with 93%yield.Based on the isolation and characterization of catalytic intermediates,a catalytic mechanism involving multipath reaction is proposed.This work provides efficient lanthanide cluster catalysts for the reduction of carboxamides to amines.
基金supported by the National Natural Science Foundation of China(21931010)。
文摘The Vaska’s complex—tris(pentafluorophenyl)borane combination was found to be a highly efficient cooperative catalysis system for the hydrosilylative reduction of tertiary amides to yield amines under mild conditions.The reaction shows high chemoselectivity,tolerating halide,phenolyl,alkenyl,nitro,nitrile,ester,azido,ketone,and enone functional groups.For unsubstituted cyclohexanone carboxamide,two variations were established to achieve either catalytic concomitant reduction of the two carbonyl groups or selective reduction of the amide carbonyl.The protocol was applied to the efficient synthesis and latestage modification of several pharmaceuticals and derivatives.Importantly,we showed that by simply prolonging reaction time to 24–28 h,the reaction can reach an exceptionally high efficiency with turnover number(TON)up to 9.8×10^(6) and turnover frequency(TOF)up to 408,333 at a quite low catalyst loading of 0.00001 mol%(S/C(Ir)=10,000,000).
基金financial supports from National Natural Science Foundation of China(21773109,91845104)~~
文摘Nanoclusters with a precise number of atoms may exhibit unique and often unexpected catalytic properties.Here,we report an atomically precise Pd3 nanocluster as an efficient catalyst,whose catalytic performance differs remarkably from typical Pd nanoparticle catalysts,with excellent reactivity and selectivity in the one-pot synthesis of benzalaniline from nitrobenzene and benzaldehyde.We anticipate that our work will serve as a starting point for the catalytic applications of these tiny atomically precise nanoclusters in green chemistry for the one-pot syntheses of fine chemicals.
