AMINOBOROHYDRIDES .8. A FACILE REDUCTION OF ALIPHATIC AND BENZYLIC AZIDES TO THE CORRESPONDING AMINES IN HIGH-YIELD AND PURITY USING LITHIUM N,N-DIMETHYLAMINOBOROHYDRIDE

Lithium N,N-dimethylaminoborohydride (LiMe(2)NBH(3)) reduced both 3 alpha-azidocholest-5-ene and 3 beta-azidocholest-5-ene in air to give the corresponding 3 alpha-aminocholest-5-ene and 3 beta-aminocholest-5-ene in 98% isolated yields. Aliphatic and benzylic azides were also reduced with LiMe(2)NBH(3) to give the corresponding amines in isolated yields ranging from 85 to 98%. The reductions were complete in 1-3 hours and required only a simple acid-base extraction to isolate the desired amines.