Bromination of Steroidal-6-ketoximes

Steroid Research Laboratory, Department of Chemistry, Aligarh Muslim University, Aligarh-202 002 Manuscript received 28 January 1988, accepted 19 February 1988 Bromination of 5α-cholestan-6-one oxime (1) with N-bromosuccinimide in carbon tetrachloride using benzoyl peroxide as a catalyst gave 6β-nitro-7α-bromocholest-4-ene (4), 7-bromocholesta-4,7-dien-6-one (5), 5α-cholestan-6-one (6) and 6-nitrocholest-5- ene (7). 3β-Chloro-5α-cholestan-6-one oxime (2) on similar treatment afforded 3β­-chloro-5-bromo-5α-cholestan-6-one (8), 3β-chloro-5α,7-dibromocholest-7-en-6-one (9) and 3β-chloro-6-nitrocholest-5-ene (10) Under similar reaction conditions, 3β-acetoxy­5α-cholestan-6-one oxime (3) yielded 3 β-acetoxy-5,7β-dibromo-5α-cholestan-6-one (11), 3β-acetoxy-7-bromocholesta-4,7-dien-6-one (12), 3β-acetoxy-6-nitrocholest-5-ene (13) and 3β-acetoxy-5α,7-dibromo-6β-nitrocholest 7-ene (14) The identity of the products has been established on the basis of their spectral data and comparison with authentic samples in known cases