Pentane → N-[(4R,4aR,6R,8aS)-8a-(2,4-difluorophenyl)-6-(fluoromethyl)-4-methyl-4,4a,5,6,8,8a-hexahydropyrano[3,4-d][1,3]thiazin-2-yl]benzamide

Participants

Reaction Steps

(Diethylamino)sulfur trifluoride (126 μL, 0.954 mmol) was added to a 0° C. solution of pentane (8 mL) and dichloromethane (5 mL). To this mixture was added N-[(4R,4aR,6R,8aS)-8a-(2,4-difluorophenyl)-6-(hydroxymethyl)-4-methyl-4,4a,5,6,8,8a-hexahydropyrano[3,4-d][1,3]thiazin-2-yl]benzamide (P2) (275 mg, 0.636 mmol) drop-wise over 10 minutes. The ice bath was removed, and the reaction mixture was allowed to warm to room temperature. After 6 hours, it was diluted with saturated aqueous sodium bicarbonate solution (20 mL) and extracted with dichloromethane (3×35 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Purification via silica gel chromatography (Gradient: 0% to 100% ethyl acetate in heptane) afforded the product as a white solid. Yield: 154 mg, 0.354 mmol, 56%. 1H NMR (400 MHz, CD3OD) δ 8.08-8.16 (m, 2H), 7.51-7.58 (m, 1H), 7.40-7.50 (m, 3H), 7.01-7.11 (m, 2H), 4.34-4.55 (m, 2H), 4.17 (br d, J=12 Hz, 1H), 3.92 (d, J=11.9 Hz, 1H), 3.9-4.02 (m, 1H), 3.18-3.28 (br m, 1H), 2.98-3.08 (br m, 1H), 1.73-1.81 (m, 1H), 1.55-1.67 (m, 1H), 1.26 (d, J=7.0 Hz, 3H).

Provenance & Evidence