Catalytic asymmetric alpha-alkylation of aldehydes via a S(N)2 '-type addition-elimination pathway

A novel method for the direct, amine-catalyzed, highly enantioselective alpha-alkylation of aldehydes is described that is founded upon the use of electrondeficient allylic halides as alkylating agents and DABCO or DMAP as coadyuvant. Both experimental observations and DFT calculations, in support of a S(N)2'-type addition-elimination pathway involving ammonium salt intermediates, are provided.