Umlagerungen bizyklischer 2-Vinyl-aziridine

Abstract

Addition of phthalimidonitrene to cyclopentadiene (5), 1,3-cyclohexadiene (6) as well as cyclooctatetraene (7) led to the bicyclic 2-vinyl-aziridines: N-phthalimido-6-aza-bicyclo[3.1.0]hex-2-ene (8a), N-phthalimido-7-aza-bicyclo[4.1.0]hept-2-ene (9a) and N-phthalimido-9-aza-bicyclo[6.1.0]nona-2,4,6-triene (10a), respectively. Thermolysis of 8a gave pyridine (16) and phthalimide (17), whereas from the thermolysis of 9a and of 10a the products of a 2-vinylaziridine-rearrangement were isolated, namely N-phthalimido-7-aza-bicyclo[2.2.1]hept-2-ene (11) and N-phthalimido-9-aza-bicyclo[4.2.1]nona-2,4,7-triene (23), respectively. 11 was found to be thermally labile under the conditions of its formation and decomposed into N-phthalimido-pyrrole (12) and, presumably, ethylene. N-Phthalimido-indole (24) was isolated as a by-product from the thermolysis of 10a. 

Hydrazinolysis of 8a and of 9a gave the corresponding N-amino-aziridines 8b and 9b, respectively. NMR-Monitoring of the CDCl₃-solutions of 8b and of 9b suggested the formation of N-amino-5-aza-bicyclo[2.1.1]hex-2-ene (22) along with cyclopentadiene (5), and of N-amino-7-aza-bicyclo[2.2.1]hept- 2-ene (13) along with 1,3-cyclohexadiene (6), respectively, as well as of hydrazine (14). In the presence of catalytic amounts of 14, 8b and 9b decomposed into cyclopentene (21) and cyclohexene (15), respectively. 

Interpretations are suggested for these highly diversified reactions.