Diastereoselective aziridination of cyclic dienes with 3-acetoxyaminoquinazolin-4(3H)-ones: competitive formation of insertion products from cyclohexadienes

Aziridination of cyclopentadiene and cycloheptadiene with 3-acetoxyamino-2-[(S)-1-hydroxy-2,2-dimethylpropyl]quinazolin-4(3H)-one 1 in the presence of titanium(IV) tert-butoxide gave the corresponding vinyl aziridines highly diastereoselectively: the corresponding aziridination product of cyclohexa-1,3-diene is formed less diastereoselectively and is accompanied by a by-product 9 from formal insertion into an allylic CH bond, a previously unobserved reaction type for 3-acetoxyaminoquinazolinones.