Tricyanovinylpyrroles: synthesis, conformational structure, photosensitizing properties, and electrical conductivity

Abstract

5-Alkyl-and 5-phenyl-substituted 2-methyl-1H-pyrroles reacting with tetracyanoethylene selectively formed of 3-(1,2,2-tricyanovinyl)pyrroles in high yields. 2-Methyl-5-(2-thienyl)-1Hpyrrole gave mixtures of 3-and 4-(1,2,2-tricyanovinyl)pyrroles (ratio 5:1). The main reaction of 2-(2-furyl)-5-methyl-1H-pyrrole with tetracyanoethylene involves attack of the 2-position of the furan ring. Ab initio calculations (HF/6-31G*) were performed to clarify the equilibrium conformation of the synthesized compounds. The photosensitizing properties and electrical conductivity were studied.