反应详情

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).

1. concentrationthe solution was concentrated
2. customthe residue was partitioned between ethyl acetate and water
3. filtrationThe white solid was filtered
4. dissolutiondissolved in a mixture of dichloromethane and methanol (9:1)
5. dry with materialThis solution was dried over magnesium sulfate
6. concentrationconcentrated