反应详情

To a solution of 3-(4-hydroxy-5,6,7,8-tetrahydro-[1]benzothiopheno[2,3-d]pyrimidin-2-yl)-propionic acid (3 g, 0.01 mol) in methanol (15 ml) was added catalytic amount of sulphuric acid (0.2 ml) and the solution was refluxed for 2 hrs. The methanol was distilled off, and the residue was washed with sodium bicarbonate solution to give 2 g (63%) of 3-(4-hydroxy-5,6,7,8-tetrahydro-[1]benzothiopheno[2,3-d]pyrimidin-2-yl)-propionic acid methyl ester as an off-white solid, which was used without further purification. 1H NMR (400 MHz, DMSO) δ ppm=1.73 (m, 4H), 2.6 (m, 2H), 2.78 (m, 2H), 2.83 (m, 4H), 3.37 (s, 3H), 12.18 (s, 1H). LC-MS: [M+H]=293.3.

1. temperaturethe solution was refluxed for 2 hrs
2. distillationThe methanol was distilled off
3. washthe residue was washed with sodium bicarbonate solution