To the stirred solution of ethyl 4-chloro-2-(methylsulfanyl)pyrimidine-5-carboxylate (4.0 g, 17.2 mmol) in ethanol in a hydrogenation vessel, Na2CO3 (1.4 g, 16.7 mmol) and 10% Pd-C (2.0 g) were added and degassed for about 10 min. The reaction mixture was kept in a hydrogenation parr shaker (60 psi) for 48 h. The reaction mixture was filtered through the elite, washed with ethanol, and concentrated under reduced pressure to get 2-(Methylthio)-5-pyrimidinecarboxylic acid ethyl ester as a pale yellow liquid (3.3 g. yield: 98.2 g, %).
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