Cyclopropyl building blocks for organic synthesis part 64 - Facile preparation of hexahydropyrrolo[3,2-e][1,4]diazepine-2,5-diones and tetrahydrofuro[1H][3,2-e][1,4]diazepine-2,5-diones by rearrangements of cyclopropylketimines and cyclopropylketones

[GRAPHICS] Chlorolactames 2a-f reacted with sodium azide to give the cyclopropylketimi nes 3a-f (75-89%), and acid hydrolysis of 3c,d yielded the cyclopropylketon es 6c,d (61-67%), Compounds 3a-f and 6c,d were transformed by heating (170- 240 degreesC, sublimation) to the air-sensitive dihydropyrroles 4a-f (51-71 %) and dihydrofurans 7c,d (85-91%), Oxidation of the dihydro derivatives 4a -f and 7c,d with DDQ led to novel types of pyrrolo[3,2-e][1,4]diazepinedion e derivatives 5a-f (75-84%) and furo[H-1][3,2-e][1,4]diazepinediones 8c,d ( 91-93%).