Enantioselective synthesis of C2-functionalized, N-protected morpholines and orthogonally N,N'-protected piperazines via organocatalysis

Tetrahedron Lett. 2012 Mar 28;53(13):1539-1542. doi: 10.1016/j.tetlet.2011.12.063. Epub 2011 Dec 29.

Abstract

In this Letter, we describe a novel three-step, one-pot procedure for the enantioselective synthesis of N-benzyl protected morpholines and orthogonally N,N'-protected piperazines with chiral alkyl groups installed at the C2 position of each heterocyclic core via organocatalysis. This methodology allows for the rapid preparation of functionalized morpholines and piperazines that are not readily accessible through any other chemistry in good to excellent % ee (55-98% ee).