Sodium borohydride → 2-[3-Chloro-4-(5-trifluoromethyl-tetrazol-1-yl)-phenyl]-3-cyclohexyl-propionic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of nickel (II) chloride hexahydrate (77 mg, 0.324 mmol) and (E)-2-[3-chloro-4-(5-trifluoromethyl-tetrazol-1-yl)-phenyl]-3-cyclohexyl-acrylic acid methyl ester (674 mg, 1.62 mmol) in methanol (15 mL) was cooled to 0° C. and then treated with sodium borohydride (184 mg, 4.86 mmol) in four portions. After the addition, the black reaction mixture was stirred for 15 min at 0° C. and then allowed to warm to 25° C. where it was stirred for 20 h. The reaction mixture was then concentrated in vacuo, and the residue was diluted with water (50 mL) and ethyl acetate (100 mL). The two layers were separated. The organic layer was washed successively with a 3N aqueous hydrochloric acid solution (1×50 mL), a saturated aqueous sodium bicarbonate solution (1×50 mL) and a saturated aqueous sodium chloride solution (1×50 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo to afford racemic 2-[3-chloro-4-(5-trifluoromethyl-tetrazol-1-yl)-phenyl]-3-cyclohexyl-propionic acid methyl ester (640 mg, 95%) as a viscous oil: EI-HRMS m/e calcd for C18H20ClF3N4O2 (M+) 416.1527, found 416.1529.

Provenance & Evidence