2-Methylbenzoic acid → 2-(5-Methyl-3-phenyl-isoxazol-4-yl)-5-o-tolyl-[1,3,4]oxadiazole

Participants

Reaction Steps

To a suspension of 5-methyl-3-phenyl-isoxazole-4-carboxylic acid hydrazide (200 mg, 0.92 mmol) in phosphorus oxychloride (1.68 mL, 18.4 mmol) was added o-toluic acid (188 mg, 1.38 mmol) and was stirred for 30 min at ambient temperature. The suspension was heated for 2 h at 90° C. whereupon it became homogeneous. After cooling to ambient temperature it was then poured onto a mixture of ethyl acetate (20 mL) and aqueous sodium carbonate (saturated, 20 mL). The aqueous phase was then separated and extracted with ethyl acetate (20 mL). The combined organic extracts were then washed with aqueous sodium carbonate and brine. Concentration and trituration in tert-butylmethylether (3 mL) afforded the title compound (99 mg, 34%) as a white solid. MS: m/e=318.1 [M+H]+.

Provenance & Evidence