The development of N-heterocyclic carbenes for application in the intermolecular Stetter reaction

Abstract

An N-heterocyclic carbene scaffold has been developed containing a protected oxygen moiety in the backbone. The oxygen provides a similar electronic effect known to fluorinated analogues, and also has the potential to be modulated via substitution. This substitution introduces steric differentiation distil to the reaction site and electronic manipulation of the calculated catalyst substrate interaction. A short synthesis has been designed with an intermediate that allows for divergent manipulation of the oxygen substituent. The resultant carbenes catalyze the intermolecular Stetter reaction with similar yields and enantioselectivities to those observed with previously designed catalysts with only fluorine substitution.