反应详情

A solution of 1.95 g (7.5 mmol) of 2-hydroxymethyl-4-phenyl-5-trifluoromethyl-thiophene (from Step A), 925 mg (7.6 mmol) of 4-hydroxybenzaldehyde and 3.0 g (11.4 mmol) of triphenylphosphene in 40 mL of THF at 0° C. was treated with 2.0 g (11.4 mmol) of diethylazodicarboxylate. The resulting mixture was warmed to rt, stirred for 2 h, then concentrated. Chromatography on a Biotage 75S cartridge using 9:1 v/v heptane/EtOAc as the eluant afforded 2.5 g of impure title compound. Chromatography on a Biotage 40M cartridge using 19:1 v/v hexanes/EtOAc (1L), then 4:1 v/v hexanes/EtOAc (1L) as the eluant afforded 1.65 g (60%) of the title compound: 1H NMR (500 Mhz) δ 5.32 (s, 2H), 7.10 (d, J=8.5, 2H), 7.12 (s, 1H), 7.41-7.43 (5H), 7.85-7.90 (2H), 9.92 (s, 1H).

1. concentrationconcentrated