N-heterocyclic carbene-catalyzed internal redox reaction of alkynals: an efficient synthesis of allenoates.

An efficient N-heterocyclic carbene (NHC)-catalyzed internal redox reaction of alkynals that bear a γ leaving group has been developed. This process provides a new access to a range of allenoates in good yields. Preliminary results demonstrate that the enantioselective variant can also be achieved.