Regiocontrolled synthesis of (hetero)aryl and alkenyl dehydropyrrolidines, dehydropiperidines and azepenes by Ru-catalyzed, heteroatom-directed α-C-H activation/cross-coupling of cyclic enamides with boronic acids

Org Biomol Chem. 2016 Jan 21;14(3):830-4. doi: 10.1039/c5ob02263k. Epub 2015 Nov 27.

Abstract

The synthesis of α-aryl and alkenyl pyrrolidine-, piperidine-, and azepane derivatives, through the intermediacy of cyclic enamides is described. The desired outcome is achieved through ruthenium-catalyzed, site-selective sp(2) C-H activation/cross-coupling with aryl and alkenyl boronic acids. The regioselectivity (α-sp(2)vs. α-sp(3)vs. β-sp(2) C-H functionalization) is governed by the rate differences between sp(2) and sp(3) C-H activation and the necessity for chelation between the ruthenium metal and the carbonyl directing group.

Publication types

  • Research Support, Non-U.S. Gov't