13316-12-6

General procedure for the synthesis of 7-chlorothiazolo[5,4-d]pyrimidine from triethyl orthoformate and 5-amino-6-chloropyrimidine-4-thiol: 5-amino-6-chloropyrimidine-4-thiol (4 g, 24.75 mmol) was dissolved in triethyl orthoformate and heated and refluxed for 1 hour. Upon completion of the reaction, the reaction mixture was concentrated to 60% of the original volume and subsequently cooled in a refrigerator. The precipitated solid was collected by filtration and dried under vacuum to afford 7-chlorothiazolo[5,4-d]pyrimidine (2.8 g, 66.04% yield) as a brown solid.1H NMR (300 MHz, CDCl3): δ 9.22 (s, 1H), 8.97 (s, 1H).

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