catalytic system of rhodium catalyst and Zn(OAc)2 additive. The presence of Zn(OAc)2 obviously accelerates the C(sp2)–H activation and destructed the formation of carboxylic ester that is formed via a nucleophilic O–H insertion to metal carbenoid. The procedure featured mild reaction conditions and broad substrate scope, providing a straightforward approach to the synthesis of α-pyrones and isocoumarins without
Rh(<scp>iii</scp>)-catalyzed C–H activation/cyclization of benzamides and diazo compounds to form isocoumarins and α-pyrones
作者:Xing Guang Li、Min Sun、Kai Liu、Qiao Jin、Pei Nian Liu
DOI:10.1039/c4cc09314c
日期:——
Rhodium-catalyzed intermolecular cyclization of benzamides and diazo compounds via C–H activation has been achieved to construct C–C/C–O bonds for the first time.
Palladium-catalyzed carbonylative cyclization via trapping of acylpalladium derivatives with internal enolates. Its scope and factors affecting the C-to-O ratio
作者:El-ichi Negishi、Christophe Copéret、Takumichi Sugihara、Izumi Shimoyama、Yantao Zhang、Guangzhong Wu、James M. Tour
DOI:10.1016/s0040-4020(01)80765-1
日期:1994.1
The Pd-catalyzed carbonylative cyclization reaction involving omega-acyl-substituted acylpalladium derivatives can proceed via intramolecular trapping with either C- or O-enolates; the preferential formation of either 5- or 6-membered rings dictates the C-to-O ratio in the trapping with enolates.