Phosphorus trichloride → 2-Methyl-1,3-benzoxazol-6-ol

Participants

Reaction Conditions

Reaction Steps

To a mixture of 1-(2,4-dihydroxy-phenyl)-ethanone oxime (4.2 g, 25 mmol) and acetonitrile/dimethylacetamide (20 mL, 3:1) cooled by a water bath (20-25° C.) was added dropwide phosphorus chloride (2.4 mL, 26.2 mmol) over a period of fifteen minutes. The mixture was stirred for an additional thirty minutes before it was poured into ice water containing sodium acetate (6 g). The mixture was stirred for ten minutes, filtered, and the filter cake was washed with water and dried in vacuo to give the title compound as a yellow solid (3.15 g): 1H NMR (CDCl3, 200 MHz): δ=7.45 (m, 1H), 6.96 (m, 1H), 6.80 (m, 1H), 2.60 (s, 3H).

Provenance & Evidence