A Michael-aldol reaction of 2-mercaptobenzaldehyde with β-indole-β-CF3 enones catalyzed by a squaramide has been realized. The method affords a series of 2-CF3-2-indole-substituted thiochromanes featuring a CF3-containing quaternary stereocenter in excellent yields, diastereoselectivities, and enantioselectivities.
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