Synthesis
In a dry 3L three-necked round-bottomed flask equipped with an overhead mechanical stirrer and an argon inlet, 32.74 g (176.7 mmol) of (4-methylamino-2-methanesulfonyl-pyrimidin-5-yl)-methanol was dissolved in 1.6 L of chloroform. Under stirring conditions, 152 g (1.75 mol) of manganese dioxide was added in batches. The reaction mixture was slightly heated and stirred continuously for 7 hours. Upon completion of the reaction, vacuum filtration was performed through a diatomaceous earth pad to remove the manganese dioxide and the filter cake was washed well with two 300mL portions of chloroform. The filtrates were combined and concentrated to give a white solid product. After vacuum drying, 30.6 g (94% yield) of 4-methylamino-2-methylthio-5-formylpyrimidine was obtained. The spectral data of the obtained product were in agreement with the values reported in the literature.
References
[1] Patent: WO2004/63195, 2004, A1. Location in patent: Page 53-54
[2] Journal of Medicinal Chemistry, 1998, vol. 41, # 17, p. 3276 - 3292
[3] Patent: WO2006/71940, 2006, A2. Location in patent: Page/Page column 355
[4] Patent: WO2008/33999, 2008, A2. Location in patent: Page/Page column 88
[5] Patent: WO2014/11900, 2014, A2. Location in patent: Page/Page column 31; 32
