5078-07-9

Synthesis, p. 68, 1982 DOI: 10.1055/s-1982-29704

The general procedure for the synthesis of 2-methyl-6-hydroxybenzoxazole from the compound (CAS:111364-29-5) was as follows: (1Z)-1-(2,4-dihydroxyphenyl)ethanone oxime (9.7 g, 57.7 mmol) was dissolved in a mixed solvent of acetonitrile (65 mL) and dimethylacetamide (11 mL) and cooled to 5 °C. Phosphorus trichloride (5.6 mL, 60.3 mmol) was slowly added dropwise at a temperature not exceeding 10 °C. After the dropwise addition, the reaction mixture was stirred at room temperature for 1 h. The reaction solution gradually formed a yellow slurry. The reaction mixture was carefully poured into a pre-prepared mixture of sodium bicarbonate and ice for neutralization. The resulting precipitate was collected by filtration and dried to give 6.3 g of 2-methyl-6-hydroxybenzoxazole in 73% yield.

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