One-pot synthesis of unsymmetrical biaryls from suitably functionalized 2H-pyran-2-ones through carbanion-induced ring-transformation reactions

Abstract

An innovative synthesis of unsymmetrical biaryls (2,6) with electron-acceptor and electron-donor substituents through carbanion-induced C–C bond formation from 6-aryl-3-cyano-4-methylthio-2H-pyran-2-ones (1) and 4-sec-amino-6-aryl-2H-pyran-2-ones (5), using aliphatic ketones as a source of carbanion, is delineated and illustrated. However, a reaction of pyran-2-ones (1) with aromatic ketones failed to yield any desired product and in lieu a new compound isolated was characterized as the corresponding (4,6-diarylpyran-2-ylidene)acetonitrile (3). The structure of two representative compounds 5h and 6q has been confirmed by single-crystal X-ray diffraction analysis.