Dichloromethane → 3-(2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyloxy)-4-[(4-bromo-2-methyl-phenyl)methyl]-5-isopropyl-1H-pyrazole

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Reaction Steps

Reagents 4-[(4-bromo-2-methyl-phenyl)methyl]-5-isopropyl-1H-pyrazol-3-ol (24.0 g, 77.6 mmol), 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide (50.4 g, 116 mmol), benzyltributylammonium chloride (4.94 g, 15.52 mmol), potassium carbonate (32.18 g, 232.9 mmol), dichloromethane (250 mL) and water (120 mL) are combined and the mixture is stirred at ambient temperature for 18 hours. The mixture is partitioned between dichloromethane (250 mL) and water (250 mL). The organic phase is washed with brine (250 mL), dried over Na2SO4, filtered, and concentrated under reduced pressure. The resulting residue is purified by flash chromatography (eluting with 10% ethyl acetate in dichloromethane to 70% ethyl acetate in dichloromethane) to give the title compound (36.5 g, 74% yield). MS (m/z): 639/641 (M+1).

Provenance & Evidence