Silver-promoted dearomative [3+4] cycloaddition of anthranils with α-isocyanoacetates: access to benzodiazepines.

The first example of silver-promoted [3+4] cycloaddition of α-isocyanoacetates with anthranils as aromatic Michael accepters, offering access to benzo[ d ][1,3]diazepinones, has been developed. Mechanistic studies revealed that an "oxygen migration" rearrangement process was involved in this dearomative cycloaddition reaction. Additionally, benzo[ d ][1,3]diazepinones were obtained efficiently as well under catalytic conditions. Broad functional groups were well tolerated under mild reaction conditions.