(alphaR)-alpha-Methyl-3,5-bis(trifluoromethyl)benzenemethanol → (2R,3R,4S)-2-[(1R)-1-(3,5-Bis(trifluoromethyl)phenyl)ethoxy]-3-(3-bromo-4-fluorophenyl)-4-vinyltetrahydropyran

Participants

Reaction Conditions

Reaction Steps

(±) 3-(3-Bromo-4-fluorophenyl)-4-vinyltetrahydropyran-2-ol (from step f) above; 10.32 g, 0.034 mol), (1R)-3,5-bis(trifluoromethyl)phenylethanol (11 g, 0.042 mol), Amberlyst™ (5 g) and molecular sieves (8 g) were suspended in dichloromethane (20 mL) and the mixture was shaken at 40° C. for 3 days. The resulting yellow solution was filtered, concentrated in vacuo and was purified by chromatography on silica using 1-5% ethyl acetate in hexane as eluant to give a mixture of isomers 1-3 (which were retained) and the desired isomer 4 (3.6 g, 20%) as a colourless oil.

Provenance & Evidence