Addition of organometallics to N-(alpha-haloacyl)-o-aminobenzonitrile resulted in the formation of 2,5-disubstituted 1,4-benzodiazepin-3-ones, whereas N-(beta-haloacyl)-o-aminobenzonitrile gave 2,6-disubstituted 1,5-benzodiazocin-4-ones under similar conditions. Initial cylization of N-(beta-haloacyl)-o-aminobenzonitrile to obtain the corresponding lactam (e.g.alpha,alpha-dimethyl-N-(2-cyanophenyl)-beta-lactam) increased the yield of 1,5-benzodiazocin-4-ones significantly. Somewhat surprisingly, addition of lithium reagents to N-(beta-haloacyl)-o-aminobenzonitrile gave 4,4-disubstituted quinazolines via Grob fragmentation.

Derivatives of o-Aminobenzonitrile. -Addition of Grignard reagents to N-(α-haloacyl)-o-aminobenzonitrile results in formation of 2,5-disubstituted 1,4-benzodiazepin-3-ones. The method is also used to prepare higher homologues 1,5-benzodiazocin-4-ones (III). Addition of lithium reagents to N-(β-haloacyl)-o-aminobenzonitrile (X) gives 4,4-disubstituted quinazolines via Grob fragmentation. -(PETTERSSON, B.; RYDBECK, A.; BERGMAN*, J.; Org. Biomol.