8-CHLORO-3-(TRIFLUOROMETHYL)[1,2,4]TRIAZOLO[4,3-A]PYRAZINE synthesis

Yield:-

Reaction Conditions:

with trichlorophosphate for 2.5 h;Heating / reflux;

Steps:

34.B

A suspension of 40 mg (0.196 mmol) of 3-(trifluoromethyl)[l,2,4]triazolo[4,3-<2]pyrazine7-oxide in 0.9 mL of phosphorus oxychloride was stirred at reflux for 2.5 h. The cooled solution wasconcentrated to dryness. Purification of the residue by preparative HPLC (C18 reverse phase column,10-70% acetonitrile in water containing 0.05% trifluoroacetic acid) and then by flash chromatography onsilica gel (10-30% ethyl acetate in hexanes) yielded the title compound as a white solid. LC-MS 223(M+l).

References:

WO2006/23750,2006,A2 Location in patent:Page/Page column 60