Hydrochloric Acid → (5-Bromopyridine-2,3-diyl)dimethanol

Participants

Reaction Conditions

Reaction Steps

Sodium borohydride (15.9 g, 420 mmol) was added portionwise over 30 min to a solution of dimethyl 5-bromopyridine-2,3-dicarboxylate (20 g, 73 mmol) in ethanol (460 mL) precooled to 0° C. A solution of calcium chloride (23.3 g, 209 mmol) in 150 mL was added slowly at 0° C., and the reaction mixture was warmed to 23° C. and stirred overnight. Excess sodium borohydride was quenched by slow addition of aqueous 2 N HCl solution (230 mL, 460 mmol), followed by a stirring at 23° C. for 2 h. The mixture was concentrated to dryness. Saturated aqueous sodium bicarbonate solution was added to the residue until a pH of approximately 7 was reached. The aqueous mixture was extracted with 2-methyltetrahydrofuran (4×200 mL). The combined organic layers were dried over sodium sulfate then treated with a solution of 4 N HCl in dioxane (25 mL, 100 mmol). The resulting solid was filtered, washed with 2-methyltetrahydrofuran, and dried to give the title compound as a hydrochloride salt. MS: m/z=218.1 (M+1).

Provenance & Evidence