反应详情

温度

100 °C

A mixture of 4-aminobenzene-1,3-diol hydrochloride (i in Scheme 1) (0.50 g, 3.1 mmol) and sodium hydrogen carbonate (2.5 mg) in methyl trimethoxyacetate (2 mL) was stirred at 100° C. overnight and then concentrated under reduced pressure. The residue obtained was purified by flash chromatography (silica gel, methylene chloride/ethyl acetate=9/1) to afford methyl 6-hydroxybenzo[d]oxazole-2-carboxylate as a white solid (0.49 g, 82%). 1H-NMR (DMSO-d6, 300 MHz): δ 10.26 (s, 1H), 7.70 (m, 1H), 7.12 (m, 1H), 6.95 (m, 1H), 3.92 (s, 3H) ppm; MS (ESI): 194.3 (M+1).

1. concentrationconcentrated under reduced pressure
2. customThe residue obtained
3. customwas purified by flash chromatography (silica gel, methylene chloride/ethyl acetate=9/1)