Beckmann Rearrangement of Ring A Steroidal Oxime Using the Carbon tetrachloride-triphenylphosphine

[摘要] The experimental procedures of Beckmann rearrangement mostly involve the use of vigorous conditions such as strongly acidic reagents (conc. HCl, H2SO4, PCl5, etc.) or elevated temperatures, which frequently cause isomerization of ketooximes prior to rearrangement.We have effected the Beckmann rearrangement on 5¥á-cholestan-3-one oxime using the carbon tetrachloride-triphenylphosphine reagent under mild, neutral conditions to give 3-aza-A-homo-5¥á-cholestan-4-one. This new, mild, facile and rapid general method of Beckmann rearrangement is presented, and compared with the classical (more conventional) Beckmann reagent of polyphosphoric acid.

[学科分类] 化学（综合）