Sodium borohydride → HCID 86713713, compound

Participants

Reaction Conditions

Reaction Steps

Compound C4 (3.00 g, 13.0 mmol) was dissolved in methanol (100 mL) and cooled to −78° C. Sodium borohydride (1.48 g, 39.1 mmol) was added portion-wise over 10 minutes, and the mixture was stirred at −78° C. for an additional 30 minutes before being allowed to warm to room temperature and stir for 1 hour. The reaction was quenched with saturated aqueous sodium bicarbonate solution (100 mL) and extracted with dichloromethane (2×150 mL). The organic layers were combined, washed with saturated aqueous sodium chloride solution (100 mL), dried over magnesium sulfate, filtered and concentrated under reduced pressure. Two purifications via silica gel chromatography [Gradients: 1) 0% to 50% ethyl acetate in heptane; 2) 0% to 50% dichloromethane in heptane] provided the title compound as a colorless oil. The product was tentatively assigned cis stereochemistry on the basis of NOE studies. Yield: 650 mg, 2.80 mmol, 22%. 1H NMR (400 MHz, CDCl3) δ 7.60 (br dd, J=7.8, 1.2 Hz, 1H), 7.47 (br ddd, J=8.2, 7.8, 1.2 Hz, 1H), 7.04 (br dd, J=7.6, 7.6 Hz, 1H), 6.87 (br d, J=8.4 Hz, 1H), 4.86-4.91 (m, 1H), 4.45-4.53 (m, 1H), 2.75 (d, J=9.2 Hz, 1H), 2.27-2.36 (m, 1H), 2.02-2.22 (m, 3H).

Provenance & Evidence