1,4-Pentenyne as a Five-Carbon Synthon for Efficient and Selective Syntheses of Natural Products Containing 2,4-Dimethyl-1-penten-1,5-ylidene and Related Moieties by Means of Zr-Catalyzed Carboalumination of Alkynes and Alkenes
作者:Gangguo Zhu、Ei-ichi Negishi
DOI:10.1002/chem.200701512
日期:2008.1
Two highly efficient protocols for enantioselective synthesis of 2,4-dimethyl-1-penten-1,5-ylidene derivatives involve the combined use of the Zr-catalyzed methylalumination of alkynes (ZMA) and the Zr-catalyzed asymmetric carboalumination of alkenes (ZACA). The ZMA/ZACA protocol has been applied to the synthesis of a nafuredin intermediate 14 and a potential intermediate 18 for milbemycin beta 3,