Palladium (II) catalyzed regioselective lactonization of steroids. Chemoselective construction of novel estrone derivatives
作者:L. Troisi、G. Vasapollo、B. El Ali、G. Mele、S. Florio、V. Capriati
DOI:10.1016/s0040-4039(99)00094-5
日期:1999.2
Palladium acetate and 1,4-bis(diphenylphosphino)butane (dppb) catalyzeregioselective cyclocarbonylation of 4-allylsteroids forming exclusively 7-membered ring lactones with excellent yields (96–98 %). The stereoselective addition of an epoxide ring on the side-chain of steroids is realized by coupling the carbonyl group of the cyclopentanone ring of the steroid with 2-benzothiazolylchloromethyllithium