Synthesis of 3,4,7,8-tetrahydro-6H-pyrido[1,2,3-ef]-1,5-benzodiazepin- 2(1H)-ones via benzotriazole methodology

Abstract

Tricyclic and tetracyclic pyridobenzodiazepin-2-one derivatives 5a-i were prepared by the reaction of 5-(benzotriazol-1-ylmethyl)-2,3,4,5- tetrahydro-1,5-benzodiazepin-2-one (4) with alkenes in the presence of a Lewis acid. For the electron-rich alkenes, zinc bromide was used as catalyst to obtain target products 5a-g; while for unactivated alkenes, a stronger Lewis acid boron trifluoride-diethyl etherate was applied to form the polycyclic products 5h,i.