Organocatalytic Enantioselective Cross-Aldol Reaction of o-Hydroxyarylketones and Trifluoromethyl Ketones.

The enantioselective cross-aldol reaction between o-hydroxyacetophenones and trifluoromethyl ketones catalyzed by chiral thiourea organocatalysts is reported. Gram-scale synthesis of the cross-aldol product was carried out, with no decrease in the yield and enantioselectivity. Furthermore, the cross-aldol products thus prepared were used in the preparation of medicinally interesting 3,5-diaryl-5-trifluoromethyl-2-isoxazoline and ß-trifluoromethyl-ß-tertiary hydroxy acid ester with high yield and enantiopurity.