Cesium carbonate → tert-Butyl 4-(5-(furan-3-yl)-[1,2,4]triazolo[4,3-a]pyrazin-8-yl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A 50 mL round bottom flask was charged with tert-butyl 4-(5-bromo-[1,2,4]triazolo[4,3-a]pyrazin-8-yl)piperazine-1-carboxylate (800 mg, 2.08 mmol), furan-3-ylboronic acid (349 mg, 3.12 mmol), Pd(PPh3)4 (240 mg, 0.312 mmol), Cs2CO3 (1.00 g, 3.12 mmol), 1,4-dioxane (11 mL) and water (4 mL). The resulting mixture was heated under N2 at 100° C. overnight. Work-up: the reaction mixture was filtered. The filter cake was washed with EtOAc (10 mL) and the filtrate was extracted with more EtOAc (10 mL×3). The combined organic solutions were washed with brine, dried over anhydrous Na2SO4, and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel with 2% methanol in dichloromethane, to afford 0.75 g (97%) of the product as a yellow solid. MS m/z: 371 (M+H+).

Provenance & Evidence