Method of synthesis and structure of (5E)-5-(2-alkoxy-2-oxoethylidene)-4-hydroxy-2,2-dimethyl-1-(4-methylphenyl)-2,5-dihydro-1H-pyrrole-3-carboxylates

A procedure has been developed for the synthesis of dialkyl (5 E )-5-(2-alkoxy-2-oxoethylidene)-4-hydroxy-2,2-dimethyl-1-(4-methylphenyl)-2,5-dihydro-1 H -pyrrole-3-carboxylates by three-component condensation of dialkyl 3,4-dihydroxyhexa-2,4-dienedioate with acetone and p -toluidine. The structure of the products is discussed on the basis of the IR, 1 H NMR, and X-ray diffraction data.