Pyridine → 7-(8-Chloroimidazo[1,5-a]pyrazin-3-yl)-3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine

Participants

Reaction Steps

To a stirred solution of N-((3-chloropyrazin-2-yl)methyl)-3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazine-7(8H)-carboxamide (1.25 g, 3.46 mmol) in Acetonitrile (10 ml) was added pyridine (2.73 g, 34.6 mmol) and finally phosphoryl trichloride (2.65 g, 17.28 mmol). The resulting reaction mixture was then stirred at room temperature for 15 hours overnight. The reaction was quenched by slowly addition of NaHCO3 and extracted with ethyl acetate (3×). The organic layer was dried by MgSO4, filtered and concentrated. The residue was purified by MPLC (24 g silica gel, 20 to 60% ethyl acetate in hexaes, 18 CV) to afford white solid product 7-(8-chloroimidazo[1,5-a]pyrazin-3-yl)-3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine (550 mg, 1.600 mmol, 46.3% yield). LC-MS: C12H9ClF3N7,343. found 344.11 [M+H]+, RT=1.22 min.

Provenance & Evidence