A practical synthesis of 5-fluoro-2-(piperidin-4-yloxy)pyrimidin-4-amine, a key intermediate in the preparation of a new class of potent deoxycytidine kinase (dCK) inhibitors, is described. The commercially available 2,4-dichloro-5-fluoropyrimidine (12) is converted in four telescoped steps to tert-butyl 4-(4-amino-5-fluoropyrimidin-2-yloxy)piperidine-1-carboxylate (6a) which upon deprotection gives 5-fluoro-2-(piperidin-4-yloxy)pyrimidin-4-amine dihydrochloride (1a) in about 68% overall yield. This process proved to be an economical alternative to a Mitsunobu-based synthesis.

中文翻译：

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实用的合成5-氟-2-（哌啶-4-基氧基）嘧啶-4-胺，这是制备强力脱氧胞苷激酶抑制剂的关键中间体

描述了一种实用的合成方法，即5-氟-2-（哌啶丁-4-基氧基）嘧啶-4-胺，它是制备新型强力脱氧胞苷激酶（dCK）抑制剂的关键中间体。市售的2,4-二氯-5-氟嘧啶（12）被转换四个伸缩步骤叔丁基4-（4-氨基-5-氟嘧啶-2-基氧基）哌啶-1-羧酸叔丁酯（6A），其在脱保护得到5-氟-2-（哌啶丁-4-基氧基）嘧啶-4-胺二盐酸盐（1a），总产率为约68％。事实证明，该方法是基于Mitsunobu的合成的经济替代方案。