反应详情

To a solution of tert-butyl 4-amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylate (example 64a) (10.7 g, 38.03 mmol) in CH2Cl2 (25 mL), was added trifluoroacetic acid (25 mL, 324.5 mmol). The reaction mixture was stirred at rt overnight. The precipitated solid was collected by filtration, and washed with CH2Cl2 to yield 4-Amino-5-methyl-2-oxo-1,2-dihydrothieno[2,3-d]pyrimidine-6-carboxylic acid (6.98 g, 82%) as a light brown solid. 1H NMR (400 MHz, DMSO-d6) δ2.78 (s, 3H). MS 226.0 (MH+).

1. filtrationThe precipitated solid was collected by filtration
2. washwashed with CH2Cl2