Organocatalytic enantioselective Diels–Alder reaction of 4,4,4-trifluorocrotonaldehyde.

A highly enantioselective Diels–Alder reaction of 4,4,4-trifluorocrotonaldehyde and dienes was performed with a diarylprolinol silyl ether catalyst. The reaction with cyclopentadiene, 1,3-cyclohexadiene, and 2-substituted 1,3-butadienes yielded the corresponding cycloadducts bearing a trifluoromethylated chiral carbon center with up to 97% ee, whereas the reaction with furan yielded the corresponding Friedel–Crafts adduct with high enantioselectivity. [ABSTRACT FROM AUTHOR]