First asymmetric synthesis of (R)-desmethylsibutramine

A catalytic enantioselective addition of iBuLi to aldimine 3 derived from methyl amine and 1-(4-chlorophenyl) cyclobutanecarboxaldehyde is used as the key step in the asymmetric synthesis of (R)-desmethylsibutramine, a single enantiomer version of a pharmacologically active metabolite of anti-obesity drug sibutramine (Meridia®).