Water → HCID 86621970, compound

Participants

Reaction Steps

To a solution of 4-(3-methylphenyl)-2-oxo-2H-chromene-7-carboxylic acid (520 mg, 1.86 mmol) and triethylamine (1.0 mL, 7.4 mmol) in THF (15 mL), cooled at 0° C., isobutylchloroformate (726 uL, 5.6 mmol) was added dropwise. After 1 hour stirring at 0° C. a solution of sodium borohydride in water (353 mg, 9.3 mmol in 6 mL) was added slowly and the mixture was stirred for another hour. The reaction mixture was poured into a saturated ammonium chloride solution and the product was extracted (3×) with ethyl acetate, the combined organic extracts were washed with water and brine, dried over MgSO4, filtered and concentrated under reduced pressure. The crude residue obtained was purified by column chromatography (ethyl acetate/hexanes, 50:50) to afford the title compound. 1H NMR (400 MHz, acetone-d6): 7.51-7.39 (m, 5H), 7.37 (d, 1H), 7.32 (d, 1H), 6.29 (s, 1H), 4.79 (d, 2H), 4.57 (t, 1H), 2.46 (s, 3H).

Provenance & Evidence