One‐Pot Procedure for the Synthesis of 1,5‐Benzodiazepines from N‐Allyl‐2‐bromoanilines

A new one‐pot procedure that includes an initial titanium‐catalyzed intermolecular hydroaminoalkylation of N‐allyl‐2‐bromoanilines with N‐methylanilines and a subsequent intramolecular Buchwald–Hartwig amination directly gives access to pharmacologically relevant 1,5‐benzodiazepines. The process takes advantage of the excellent regioselectivity of the initial hydroaminoalkylation performed in the presence of a titanium mono(formamidinate) catalyst and the fact that the exclusively formed branched hydroaminoalkylation products can only undergo palladium‐catalyzed cyclization to 1,5‐benzodiazepines. An aminated story: 1,5‐Benzodiazepines are directly obtained from tertiary N‐allyl‐2‐bromoanilines and N‐methylanilines using an efficient one‐pot procedure. The new process combines an initial highly regioselective titanium‐catalyzed intermolecular hydroaminoalkylation of an allylamine with a subsequent palladium‐catalyzed intramolecular Buchwald–Hartwig amination.