Sodium borohydride → Racemic 2-[3-chloro-4-(5-methyl-tetrazol-1-yl)-phenyl]-3-cyclopentyl-propionic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of nickel (II) chloride hexahydrate (180 mg, 0.8 mmol) and (E)-2-[3-chloro-4-(5-methyl-tetrazol-1-yl)-phenyl]-3-cyclopentyl-acrylic acid methyl ester (695 mg, 2.0 mmol) in methanol (15 mL) was cooled to 0° C. and then treated with sodium borohydride (454 mg, 12 mmol) in five 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 2 d. The reaction mixture was concentrated in vacuo, and the residue was diluted with a 3N aqueous hydrochloric acid solution (50 mL) and ethyl acetate (75 mL). The two layers were separated. The organic layer was washed with 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-methyl-tetrazol-1-yl)-phenyl]-3-cyclopentyl-propionic acid methyl ester (815 mg, 99%) as a viscous oil: EI-HRMS m/e calcd for C17H21ClN4O2 (M+) 348.1353, found 348.1359.

Provenance & Evidence