A concise and general methodology for the complete asymmetric synthesis of the orthogonally protected 2-amino-1,3,4-butanetriols (ABTs)

A complete asymmetric synthesis of the orthogonally protected 2-amino-1,3,4-butanetriols I (ABTs: versatile four carbon chiral synthons) was accomplished via the regioselective asymmetric aminohydroxylation (AA) reaction and oxazoline chemistry in four to six steps from the starting olefin 1. The syn-vicinal amino alcohol functionality of I was installed by the regioselective AA reaction of the achiral olefin 1 in a single step, and the anti-vicinal amino alcohol functionality of I was derived from the syn-amino alcohol 2 by inverting the C2 hydroxy group stereochemistry through the formation and hydrolysis of the oxazoline 7. Thus, the present strategy represents the most efficient and general asymmetric synthesis of ABTs so far.