Potassium Carbonate → 2-(3,4-Dimethoxy-phenyl)-5-(2-methylsulfanyl-pyrimidin-5-yl)-imidazo[2,1-b][1,3,4]thiadiazole

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Reaktionsschritte

A mixture of 2-(3,4-dimethoxy-phenyl)-5-iodo-imidazo[2,1-b][1,3,4]thiadiazole (0.25 g, 0.646 mmol, 1 eq), 2-(methylthio)pyrimidine-5-boronic acid pinacol ester (0.244 g, 0.968 mmol, 1.5 eq) and K2CO3 (0.357 g, 2.584 mmol, 4 eq) in 1,2-DME/H2O (9/1, 5 mL) was stirred at RT for 10 min. Then, PdCl2(dppf) (0.053 g, 0.0646 mmol, 0.1 eq) was added and the reaction mixture was heated at 85° C. for 4 h. Solvents were evaporated and water was added to the residue. The suspension was extracted with EtOAc (×3) and the combined organics were dried, filtered and evaporated. The residue was purified in an Isolute Si II cartridge using MeOH in DCM (0% to 1%) to give the desired product (47 mg). The aqueous phase was evaporated to dryness and the residue was redissolved in DCM and filtered. The filtrate was evaporated and purified as described before to give additional desired product (136 mg). Total amount obtained: 183 mg. Overall yield: 73%. HPLC-MS: (5-100% B in 8 min, 0.8 mL/min, 50° C.): tR=5.46 min, [M+H]+ m/z 386.2; 1H NMR (300 MHz, CDCl3) δ 9.15 (d, J=5.8 Hz, 2H), 7.64 (s, 1H), 7.45 (m, 2H), 6.97 (m, 1H), 3.99 (s, 3H), 3.98 (s, 3H), 2.64 (s, 3H).

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