Lithium Hydroxide → 2-(5-Cyano-7-isopropyl-1,3-benzoxazol-2yl)pyrimidine-5-carboxylic acid

Participants

Reaction Steps

To a solution of methyl-2-(5-cyano-7-isopropyl-1,3-benzoxazol-2yl)pyrimidine-5-carboxylate (429 mg, 1.332 mmol) in tetrahydrofuran (30 ml) was added 1N lithium hydroxide (1.466 ml) dropwise at 60° C. The reaction mixture was stirred at room temperature for 4 h, and then the solution was concentrated and the residue was partitioned between ethyl acetate and water. The aqueous layer was acidified with 1N HCl to pH=4˜5. The white solid was filtered and dissolved in a mixture of dichloromethane and methanol (9:1). This solution was dried over magnesium sulfate and then concentrated to provide the title compound (74 mg) as a yellow solid. Mass spectrum (ESI) 308.8 (M+1). 1H NMR (500 MHz, DMSO) δ 9.45 (s, 2H), 8.42 (s, 1H), 7.92 (s, 1H), 3.20˜3.60 (m, 1H, overlapped with H2O peak), 1.41 (s, 6H).

Provenance & Evidence