Cesium carbonate → HCID 53391274, compound

Participants

Reaction Conditions

Reaction Steps

A 50 mL round bottom flask was charged with 5-bromo-6-methyl-8-(4-methylpiperazin-1-yl)tetrazolo[1,5-a]pyrazine (0.72 g, 2.3 mmol), thiophene-2-boronic acid (0.46 g, 3.6 mmol), tetrakis(triphenylphosphine)palladium(0) (0.30 g, 0.26 mmol), Cs2CO3 (1.2 g, 3.7 mmol), 1,4-dioxane (12 mL) and water (6 mL). After the air was purged by bubbling N2 into the solution, the resulting mixture was stirred at 100° C. under N2 atmosphere overnight. Work-up: the reaction mixture was poured into 0.1 M HCl (40 mL) and washed with EtOAc (50 mL×2). The aqueous layer was then basified with solid NaHCO3 and extracted with CH2Cl2 (50 mL×3). The combined CH2Cl2 layers were dried over anhydrous Na2SO4 and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel with 5% MeOH in CH2Cl2, to afford 165 mg (23%) of the product as a white solid. 1H NMR (300 MHz, CDCl3) δ: 7.59 (dd, J=5.1, 1.2 Hz, 1H), 7.38 (dd, J=3.6, 1.2 Hz, 1H), 7.21 (dd, J=5.1, 3.6 Hz, 1H), 4.40 (br, 4H), 2.60 (t, J=5.1 Hz, 4H), 2.47 (s, 3H), 2.38 (s, 3H). MS m/z: 316 (M+H+).

Provenance & Evidence