Reactivity of electrogenerated N-heterocyclic carbene in room-temperature ionic liquids. Cyclization to 2-azetidinone ring via C3-C4 bond formation

The intrinsic chemistry of imidazolium- based room-temperature ionic liquids, related to the acidity of the C-2 imidazolium cation, can be modi- fied via cathodic cleavage of the C-2/hydrogen bond. N-Heterocyclic carbenes, electrogenerated by elec- trolysis of imidazolium-based room-temperature ionic liquids, are stable bases that are strong enough to deprotonate bromoamides 1a–k yielding the azeti- din-2-one ring via C-3/C 4 bond formation. The electrosynthesis of b-lactams 2a–k has been achieved under mild conditions, elevated yields and avoiding the use of toxic, volatile, molecular solvents.