Stereoselectivity of lithium aluminium hydride and lithium alkoxyaluminohydride reductions of 3,3,5-trimethylcyclohexanone in diethyl ether

Article abstract of DOI:10.1021/jo00314a021

The stereochemistry of lithium aluminum hydride and lithium tert-butoxyaluminohydride reductions of 3,3,5-trimethylcyclohexanone in diethyl ether has been studied.An unusual nonmonotonic dependence of the percentage of trans-3,3,5-trimethylcyclohexanol formed upon the ratio of : is observed.These unusual results have led to the use of diol addends to LiAlH4 solutions in order to probe the role of disproportionation upon stereoselectivity.Lithium mono-tert-butoxyaluminohydride is proposed to have a radically different stereoselectivity from that of either LiAlH4 or LiAl(O-t-Bu)3H.