4-Toluenesulfonyl chloride → 3-(5-Benzyl-1,3,4-oxadiazol-2-yl)-5-bromo-6-(trifluoromethyl)pyrazin-2-amine

Participants

Reaction Steps

To a solution of 3-amino-6-bromo-N′-(2-phenylacetyl)-5-(trifluoromethyl)pyrazine-2-carbohydrazide (step 1) (92 mg, 0.220 mmol) in THF (2 ml) was added a solution of TsCl (50 mg, 1.200 mmol) in THF (0.5 ml). The resulting solution was then added to PS-BEMP (384 mg, 1.100 mmol) and the mixture was heated using microwave radiation at 120° C. for 10 min. The reaction mixture was loaded onto an Isolute® PE-AX/SCX-2 cartridge (10 g, Solid Phase Extraction) pre-wetted with THF. The cartridge was eluted with THF (40 ml) and the organic portion was concentrated in vacuo. The crude product was purified by chromatography on silica eluting with 20% EtOAc/iso-hexane followed by further purification by preparative HPLC to afford the title compound; 1H NMR (400 MHz, DMSO-d6) δ 7.35 (5H), 4.49 (2H, s). LC-MS Rt=5.76 min [M+H]+ 400.1 Method 10minLC_v002.

Provenance & Evidence