Asymmetric Synthesis of Allylamines by Regio- and Diastereoselective 1,2-Addition of Organolithium Reagents to Conjugated Sulfinimines.

A practical, robust, and straightforward access to optically enriched allylamines by a regio- and diastereoselective 1,2-addition of organolithium reagents to Davis-Ellman-type chiral conjugated sulfinimines is reported. The procedure is operationally simple, proceeds under mild conditions, requires readily available starting materials, and consistently delivers complete regiocontrol in favor of 1,2-addition. Synthetically useful levels of diastereoselectivity can be obtained in all cases, and the reaction tolerates a broad range of organolithium reagents and substitution patterns on the sulfinimine. The method further enables a one-pot 1,2-addition/N-functionalization sequence through in situ trapping of the transient lithiated sulfinamide, constituting a formal 1,2-difunctionalization of the C═N bond and expanding the structural diversity accessible in a single operation.