Synthesis of cholestanes containing an oxygenated 14\u3b1-methyl group

Hydrocyanation of 3\u3b2-acetoxy-5\u3b1-cholest-8(14)-en-7-one has been achieved by reaction with diethylaluminium cyanide. The resulting 14\u3b1-cyano-7-ketone was reduced with sodium borohydride to the 7\u3b1-hydroxy-compound, the methanesulphonate of which, when refluxed in collidine, gave 3\u3b2-acetoxy-5\u3b1-cholest-7-ene-14\u3b1-carbonitrile. Reduction of the cyano-group with di-isobutylaluminium hydride afforded 3\u3b2-hydroxy-5\u3b1-cholest-7-ene-14\u3b1-carbaldehyde, which was transformed with lithium aluminium hydride into 14\u3b1-hydroxymethyl-5\u3b1-cholest-7-en-3\u3b2-ol