Synthesis of nitrile derivatives of estrogens.

The first time synthesis of 7alpha- and 11beta-nitrile estradiol is described. Reaction of 7alpha-cyano-19-nortestosterone with copper(II)bromide in acetonitrile at room temperature results in aromatization of the A-ring. Treatment of 11beta-cyano-19-nortestosterone-17-one under similar condition does not induce A-ring aromatization but rather results in bromination at the 2beta-position. However A-ring aromatized products are obtained when the latter compound is treated with Ac2O-Py-AcOCl, NBS and HCl.