反应详情

温度

120 °C

Methyl 4-(1,1-dimethyl-1-stannaethyl)-5-methylthiothiophene-2-carboxylate (195 mg, 0.56 mmol) as prepared in previous step, and 2,6-dibromopyridine (398 mg, 1.7 mmol) were taken in anhydrous DMF (2 mL). To this mixture tetrakistriphenylphosphine-palladium (20 mg) was added and heated at 120° C. for 24 h. DMF was removed under vacuum and the residue was purified by preparative silica gel thin-layer chromatography to give 78 mg (41%) of methyl 4-(6-bromo(2-pyridyl))-5-methylthiothiophene-2-carboxylate as a solid. 1H-NMR (CDCl3; 300 MHz) δ2.60 (S, 3H), 3.78 (s, 3H), 7.19 (S, 1H), 7.47 (dd, J=1.09 and 7.67 Hz, 1H)), 7.58 (t, J=7.70, 1H), 7.65 (dd, J=1.12 and 7.43 Hz, 1H).

1. customDMF was removed under vacuum
2. customthe residue was purified by preparative silica gel thin-layer chromatography