Highly diastereoselective reduction of (-) menthylphenylglyoxalate and (-) menthylpyruvate using new hindered lithiumtrialkoxyaluminohydrides

Article abstract of DOI:10.1016/S0957-4166(00)80456-5

Reduction of the keto group of (-) menthylphenylglyoxalate and (-) menthyl pyruvate can be achieved with high diastereoisomeric excess (80-90percent) using newly synthesized hindered lithium trialkoxyaluminium hydrides in THF at -78 deg C.Hindered borohydrides such as lithium trisiamylborohydride reduce those ketoesters with a lower diastereoselectivity.