New derivatives of the 1,2-benzodiazepine ring system

The adducts 10, formed in high yield by condensations between the benzotria zole dianion 2 and enals 9, undergo smooth oxidation by manganese(IV) oxide to provide the expected conjugated enones. These then cyclise at varying r ates, depending upon the substitution pattern around the enone function, by intramolecular Michael addition of the NHBoc group to provide examples 13 of a novel ring system based upon a 4,5,6,7-tetrahydro-1,2-benzodiazepine c ore. Allylic acetates 16 derived from the initial adducts 10 also undergo c yclisations via the derived pi -allyl palladium complexes 15 to provide exa mples of the corresponding 4,5-dihydro-1,2-benzodiazepinenes 17, but in a l ess general manner.