We examined the puzzling mechanism for Cu-catalyzed meta-C-H arylation reaction of anilides by diaryliodonium salts through systematic theoretical analysis. The previously proposed anti-oxy-cupration mechanism featuri...We examined the puzzling mechanism for Cu-catalyzed meta-C-H arylation reaction of anilides by diaryliodonium salts through systematic theoretical analysis. The previously proposed anti-oxy-cupration mechanism featuring anti-1,2- or anti-1,4-addition of cuprate and oxygen to the phenyl ring generating a meta-cuprated intermediate was excluded due to the large activation barriers. Alternatively, a new amide-directed carbocupration mechanism was proposed which involves a critical rate- and regio-determining step of amide-directed addition of the Cu（III）-aryl bond across the phenyl C2=C3 double bond to form an orthocuprated, meta-arylated intermediate. This mechanism is kinetically the most favored among several possible mechanisms such as ortho-or para-cupration/migration mechanism, direct meta C-H bond cleavage mediated by Cu（III） or Cu（I）, and Cu（III）-catalyzed ortho-directed C-H bond activation mechanism this mechanism has been shown to Furthermore, the predicted regioselectivity based on favor the meta-arylation that is consistent with the experimental observations.展开更多
An efficient method for the synthesis of α-phenylcinnamates via silver catalyzed C—C bond activation reaction of cyclopropenone and alcohol was developed.This protocol features a simple reaction system,specific regi...An efficient method for the synthesis of α-phenylcinnamates via silver catalyzed C—C bond activation reaction of cyclopropenone and alcohol was developed.This protocol features a simple reaction system,specific regioselectivity,good functional group compatibility and good yields.It is of great significance for the later modification of natural products.展开更多
基金This work was supported by the National Natural Science Foundation of China （No.20971058） and the Fundamental Research Funds for the Central Universities （No.JUSRPIII05）.
文摘We examined the puzzling mechanism for Cu-catalyzed meta-C-H arylation reaction of anilides by diaryliodonium salts through systematic theoretical analysis. The previously proposed anti-oxy-cupration mechanism featuring anti-1,2- or anti-1,4-addition of cuprate and oxygen to the phenyl ring generating a meta-cuprated intermediate was excluded due to the large activation barriers. Alternatively, a new amide-directed carbocupration mechanism was proposed which involves a critical rate- and regio-determining step of amide-directed addition of the Cu（III）-aryl bond across the phenyl C2=C3 double bond to form an orthocuprated, meta-arylated intermediate. This mechanism is kinetically the most favored among several possible mechanisms such as ortho-or para-cupration/migration mechanism, direct meta C-H bond cleavage mediated by Cu（III） or Cu（I）, and Cu（III）-catalyzed ortho-directed C-H bond activation mechanism this mechanism has been shown to Furthermore, the predicted regioselectivity based on favor the meta-arylation that is consistent with the experimental observations.
基金Project supported by the National Natural Science Foundation of China(No.21702160)the State Key Laboratory of Fine Chemicals,Dalian University of Technology(No.KF2311)。
文摘An efficient method for the synthesis of α-phenylcinnamates via silver catalyzed C—C bond activation reaction of cyclopropenone and alcohol was developed.This protocol features a simple reaction system,specific regioselectivity,good functional group compatibility and good yields.It is of great significance for the later modification of natural products.
