Asymmetric Aldol Reaction of Dichloroacetaldehyde Catalyzed by Diarylprolinol

The asymmetric cross-aldol reaction of dichloroacetaldehyde with aldehyde pronucleophiles proceeds in the presence of a trifluoromethyl-substituted diarylprolinol to afford γ,γ-dichloro-β-hydroxy aldehydes in good yield with excellent enantioselectivity. The obtained products are useful synthetic intermediates; they were successfully converted to form chiral alkynes and dichloroalkenes. (Figure presented.) .