The present application provides a one-pot catalytic process which involves the formation of 1,4-dibenzodiazepines from o-haloaldimines (either pre-formed or formed in situ) of formula (I) and o-haloanilines of formula (II) via a palladium catalyzed Buchwald-Hartwig reaction and a cyclization sequence, to afford the 1,4-dibenzodiazepine products of formula (III). The present application describes the preparation of the 1,4-dibenzodiazepine products of formula (III) from simple commercial raw materials by efficient processes.