conversion of a delta - 16 - steroids in a delta - 17 (20) - 20 silylether.

摘要

The present invention is a process for conversion of DELTA 16-steroids (I) IMAGE (I) to the corresponding DELTA 17(20)-20-silyl ether (III) IMAGE (III) by reaction with (1) a preformed copper hydride or a metal hydride reducing agent in the presence of a copper species and (2) a silylating agent. The DELTA 17(20)-20-silyl ether (III) are useful intermediates in the preparation of steroids useful as pharmaceuticals.