An Environmentally Sustainable Synthesis of Enantioenriched CF3-Chromanol, Indanol and Tetralol Derivatives by Rh-Catalyzed Asymmetric Transfer Hydrogenation

The Rh(III)-catalyzed asymmetric reduction of alpha-trifluoromethyl ketones through transfer hydrogenation was developed under mild conditions to access a series of enantioenriched cis-trifluoromethyl alcohols via a dynamic kinetic resolution process. The reaction was efficiently performed in the green solvent 2-MeTHF with HCO2H/Et3N (1 : 1) as the hydrogen source. High yields, alongside excellent diastereo- and enantioselectivities were obtained for the synthesis of CF3-chromanol, CF3-indanol and CF3-tetralol derivatives.