THERMAL REARRANGEMENT OF 3H-PYRROLES BY COMPETITIVE -SIGMATROPIC SHIFTS, AND THE REVERSIBILITY OF THE 3H- TO 2H-PYRROLE INTERCONVERSION

Article abstract of DOI:10.1016/S0040-4039(00)96207-5

3-Ethoxycarbonyl-3H-pyrroles are converted via thermal <1,5>-ester shifts to the isomeric 1H-pyrrole-4- and N-esters.Isolable intermediate 2H-pyrroles are converted into the same products, and also into the 3H-pyroles, demonstrating conclusively the reversibility of the 3H- to 2H-pyrrole interconversion.