Reinvestigation of Alternative Method for the Preparation of Dibenz[bf][1,4]oxazepine

摘要

Two distinct alternative methods using different starting materials for the preparation of dibenz[bf] [1,4]oxazepine (7, CR) were reinvestigated. The possibility of trans-cis conversion of the Schiff base 5 (produced from 1 and 2) is considered the favorable orientation that leads to cyclization (production of 7). Fluoro derivative of I afforded excellent and more convenient conditions for the one pot preparation of high yield pure 7. The presence of only trans configurafion for the imine 6 (produced from 3 with 4) and the impossibility of its conversion to cis, makes it inadequate for the preparation of 7.