Synthesis of chiral non-racemic 1,2-diamines from O-acetyl mandelic acid: application in enantioselective deprotonation of epoxides and diethylzinc addition to aldehydes

A variety of 1,2-diamines were synthesized from readily available O-acetyl mandelic acid. These diamines were used in the synthesis of key intermediates for the preparation of (−)-utenone A and carbovir involving enantioselective deprotonation of epoxides. The addition of Et2Zn catalysed by some of these diamines was also studied and although ees were not high, some interesting observations were made in the outcome of the stereochemistry of the product.