Diastereoselective hydroxymethylation of cyclic N-tert-butanesulfinylketimines using methoxymethanol as formaldehyde source.

ABSTRACT

Hydroxymethylation of cyclic tert-butanesulfinylketimine-derived lithium enamides with methoxymethanol proceeds with excellent diastereoselectivity (991 dr). Methoxymethanol is a stable and easy-to-handle source of anhydrous monomeric formaldehyde in the reaction with lithium enamides. Cyclic α-hydroxymethyl ketimines undergo highly diastereoselective reduction to syn- or anti-1,3-amino alcohols.