7-CHLORO[1,2,4]TRIAZOLO[1,5-A]PYRIMIDINE synthesis

Yield:52341-91-0 26.4%

Reaction Conditions:

Stage #1: 7-hydroxy-5-[1,2,4]triazolo-[1,5-a]pyrimidinewith trichlorophosphate for 6 h;Reflux;
Stage #2: with water in chloroform;Cooling;

Steps:

5.c

c. A solution of [l,2,4]triazolo[l,5-a]pyrimidin-7-ol (43) (1 g, 7.34 mmol) in phosphorous oxy chloride (22.53 g, 146.93 mmol) was heated at reflux for 6 h. The reaction was cooled to room temperature and concentrated in vacuum to dryness. The residue obtained was dissolved in chloroform (50 mL) and washed with cold water (50 mL). The aqueous layer was extracted with chloroform (2 x 100 mL). The organic layers were combined washed with water (100 mL), brine (50 mL), dried and concentrated in vacuum to afford 7-chloro-[l,2,4]triazolo[l,5-a]pyrimidine (44) (0.3 g 26.4%) as a colorless solid. ¹H NMR (300 MHz, DMSO) δ 9.48 (d, J= 7.1, IH), 8.72 (s, IH), 7.53 (d, J= 7.1, IH).

References:

WO2010/14930,2010,A2 Location in patent:Page/Page column 47