Water → 1-(Benzo[d]oxazol-5-yl)cyclopropanecarboxylic acid

Participants

Reaction Steps

To a solution of crude 1-benzooxazol-5-yl-cyclopropanecarboxylic acid methyl ester (2.9 g) in EtSH (30 mL) was added AlCl3 (5.3 g, 40.1 mmol) in portions at 0° C. The reaction mixture was stirred for 18 hours at room temperature. Water (20 mL) was added dropwise at 0° C. The resulting mixture was extracted with EtOAc (100 mL×3). The combined organic layers were dried over anhydrous Na2SO4 and evaporated under vacuum to give the crude product, which was purified by column chromatography on silica gel (petroleum ether/EtOAc 1:2) to give 1-(benzo[d]oxazol-5-yl)cyclopropanecarboxylic acid (280 mg, two steps: 11%). NMR (DMSO, 400 MHz) δ 12.25 (brs, 1H), 8.71 (s, 1H), 7.70-7.64 (m, 2H), 7.40 (dd, J=1.6, 8.4 Hz, 1H), 1.49-1.46 (m, 2H), 1.21-1.18 (m, 2H). MS (ESI) m/e (M+H+) 204.4.

Provenance & Evidence