3-Hydroxypyrroles and 1H-pyrrol-3(2H)-ones. Part 1. Formation and X-ray crystal and molecular structure of 1-cyclohexyl-2,2-pentamethylene-1H-pyrrol-3(2H)-one

Abstract

The title compound (4) is formed by flash vacuum pyrolysis of a dicyclohexylaminomethylene derivative of Meldrum's acid, (2), and its structure was determined by X-ray crystallography. Deuterium-labelling studies show that the reaction mechanism involves a specific, intramolecular, rate-determining hydrogen transfer from the 1-position of a cyclohexyl ring to form the 4-hydrogen atom in the product.