3-Buten-1-ol → 4-{4-[(1E)-4-hydroxybut-1-en-1-yl]-2-methylbenzyl}-5-(propan-2-yl)-1H-pyrazol-3-yl 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside

Participants

Reaction Conditions

Reaction Steps

Add 3-buten-1-ol (6.1 mL, 70 mmol) to a solution of 4-(4-bromo-2-methylbenzyl)-5-(propan-2-yl)-1H-pyrazol-3-yl 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside (15 g, 23.5 mmol) in acetonitrile (200 mL) and triethylamine (50 mL). Degas the solution with nitrogen over 10 minutes. Add tri-o-tolylphosphine (1.43 g, 4.7 mmol) and palladium acetate (526 mg, 2.35 mmol). After refluxing at 90° C. for 2 hours, cool and concentrate to remove the solvent under reduced pressure. Purify the resulting residue by flash chromatography (silica gel, gradient ethyl acetate/hexanes from 20-80% over 20 min, 330 g column) to provide the title compound (7.5 g, 11.9 mmol). MS (m/z): 631.2 (M+1), 629.2 (M−1).

Provenance & Evidence