The photochemistry of 2-diazo- and 3-diazopyrroles has been investigated. The irradiation of 2-diazo-3-cyano-4-methyl-5-phenylpyrrole in various reaction solvents brings to a photolytic singlet carbene intermediate, which evolves into 2-substituted pyrroles. A substituent effects has been recognized in the irradiations of some 3-diazopyrroles in methanol.
Dattolo; Cirrincione; Almerico, Il Farmaco, 1993, vol. 48, # 2, p. 191 - 194