General Procedures for the Lithiation/Trapping of N-Boc Piperazines

J Org Chem. 2017 Jul 7;82(13):7023-7031. doi: 10.1021/acs.joc.7b00913. Epub 2017 Jun 20.

Abstract

To provide α-substituted piperazines for early stage medicinal chemistry studies, a simple, general synthetic approach is required. Here, we report the development of two general and simple procedures for the racemic lithiation/trapping of N-Boc piperazines. Optimum lithiation times were determined using in situ IR spectroscopy, and the previous complicated and diverse literature procedures were simplified. Subsequent trapping with electrophiles delivered a wide range of α-functionalized N-Boc piperazines. The scope and limitations of the distal N-group were investigated. The selective α- and β- arylation of N-Boc piperazines via lithiation/Negishi coupling is reported.

Publication types

  • Research Support, Non-U.S. Gov't