Fine-tuned aminal cleavage: a concise route to differentially protected enantiopure syn-alpha,beta-diamino Esters.

A survey of routes for aminal cleavage of N-sulfinylimidazolidines has been carried out, and selective conditions to cleave the aminal moiety while preserving the sulfinamide group unaltered have been found. Thus, the treatment of enantiopure N-sulfinylimidazolidines with aqueous H(3)PO(4) in THF affords enantiopure N-sulfinyldiamino esters in excellent yields, while the presence of MeOH as cosolvent allows for the simultaneous removal of the sulfinamide group and aminal cleavage. The behavior of these substrates in a variety of chemical transformations has been explored.