
%0 Journal Article
%A Collins, DJ 
%A Hobbs, JJ 
%T The lability of 6-Bromo-&#916;<sup>4</sup>-3-oxosteroids: Observations on the conversion of 6&#945;- and 6&#946;-Bromocholest-4-en-3-one to 5&#945;-Cholestane-3,6-dione
%J Australian Journal of Chemistry
%D 1964/06/01
%V 17
%N 6
%P 661-676
%K 
%R https://doi.org/10.1071/CH9640661
%U https://www.publish.csiro.au/paper/CH9640661 
%X Cholesta-4,6-dien-3-one, cholest-4-ene-3,6-dione, 5&#945;-cholestane-3,6-dione, cholest-4-en-6&#946;-ol-3-one, cholest-4-en-2&#945;-ol-3-one, cholest-4-en-4-ol-3-one, and cholesta-2,5-dien-3-ol-4-one, are formed in greater or lesser amounts during chromatography of 6&#945;- and 6&#946;-bromocholest-4-en-3-one over neutral or alkaline alumina.   The conversion of 6&#945;- and 6&#946;-bromocholest-4-en-3-one to 5&#945;-cholestane-3,6-dione by the action of methanolic hydrochloric acid has been examined. The use of concentrated hydrochloric acid in this reaction afforded 3,3-dimethoxy-5&#945;-cholestan-6-one in good yield. Under similar conditions, the same ketal was also obtainable from 6&#946;-methoxycholest-4-en-3-one, cholest-4-en-6&#946;-ol-3-one, and 5&#945;-cholestane-3,6-dione.   The course of the reactions of the epimeric 6-bromocholest-4-en-3-ones with acidic ethanol, isopropanol, and t-butanol is discussed. 
