To a solution of the {4-[(S)-6-(4-chloro-2-methanesulfonylphenyl)-4-hydroxy-6-methyl-4-trifluoromethylhept-1-ynyl]-6-methanesulfonylpyridin-3-yl}carbamic acid tert-butyl ester (18.3 g, 28.0 mmol) in 200 mL of methanol was added DBU (12.5 mL, 84.0 mmol). The reaction was heated to 70° C. for 1.5 hours. The reaction was added to a solution of saturated aqueous ammonium chloride solution resulting in the precipitation of a white solid that was collected by vacuum filtration. The solid was washed with water and, after drying under vacuum for 30 minutes, was suspended in 50 mL of cold diethyl ether then vacuum filtered again and washed with 50 mL of cold diethyl ether. The colorless solid was dried on the filter paper under suction to provide (R)-4-(4-chloro-2-methanesulfonylphenyl)-1,1,1-trifluoro-2-(5-methanesulfonyl-1H-pyrrolo[2,3-c]pyridin-2-ylmethyl)-4-methylpentan-2-ol (15.4 g, 99%).
