Gaebert C, Mattay J. [3+2] cycloadditions of aziridines mechanistical studies. JOURNAL OF INFORMATION RECORDING. 1996;23(1-2):3-6.The reaction of 1-butyl-2-phenyl aziridine with dimethyl acetylenedicarboxylate under PET conditions yields four products, two isomeric pyrrolidines and the corresponding pyrroles as oxidation products from the pyrrolidines. The reaction of the aziridine with dimethyl maleate and dimethyl fumarate respectively under PET conditions yields pyrroles with retained stereochemistry of the dipolarophiles. The addition of acrylonitrile to 1-butyl-trans-2,3-diphenyl aziridine under PET conditions leads to all four possible isomeric pyrrolidines whereas under direct photolysis only two pyrrolidines are formed. Based on these experimental data the mechanism involving a radical cation will be discussed
