Dimethyl bromomalonate undergoes manganese(III)-promoted free-radical chain addition reaction with olefins, to yield dimethyl 2-bromoalkylmalonates. Organocatalyzed Michael addition of dimethyl bromomalonate to nitrostyrenes to yield synthetically useful nitrocyclopropanes has been reported. Dimethyl bromomalonate reacts readily with arylnitroso compounds to yield the corresponding N-aryl-C,C-dimethoxycarbonylnitrones.