Synthesis of 2-chloro-4-(3-nitrophenoxy) thieno [3, 2-d] pyrimidine

2, 4-dichloro-6-(3-nitrophenoxy) pyrimidine is an important intermediate of small molecule anticancer drugs. In this work, a rapid synthetic method for target compounds was established. Compound (4) was synthesized from methyl 3-aminothiophene-2-carboxylate and urea through three steps including cyclization, chlorination and nucleophilic substitution. The structure of the target compound was confirmed by 1H NMR and MS spectrum. Furthermore, the synthetic method was optimized. The total yield of the three steps was 42.4%.