2,2'-Bipyridine → HCID 67469070, compound

Participants

Reaction Conditions

Reaction Steps

Methyl 6-bromo-1H-indazole-4-carboxylate (1.0 g, 3.92 mmol) was dissolved in 1,2-Dichloroethane (DCE) (14 mL) and stirred for 15 min. Next added cyclopropylboronic acid (0.674 g, 7.84 mmol) and sodium carbonate (0.831 g, 7.84 mmol). The reaction was stirred at RT (suspension). Copper (II) acetate (0.712 g, 3.92 mmol) and 2,2′-bipyridine (0.612 g, 3.92 mmol) were suspended in DCE (24 mL) with heating and the hot suspension was added to the reaction mixture. The contents were stirred with heating at 70° C. overnight. After cooling to RT, the reaction mixture was poured onto sat. NH4Cl and ice. Next added DCM and stirred for 10 min. The contents were filtered through Celite, washing with water and DCM. The layers were separated and the aq. layer was extracted with DCM (1×). The combined organic layers were washed with brine, dried over MgSO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography (3-25% gradient ethyl acetate in hexanes) wherein the less polar product was observed to be the title compound, and was collected as a yellow solid (0.54 g, 46%); 1H NMR (400 MHz, DMSO-d6) δ ppm 1.10-1.20 (m, 4H), 3.81-3.90 (m, 1H), 3.95 (s, 3H), 7.86 (d, J=1.52 Hz, 1H), 8.30 (d, J=1.77 Hz, 1H), 8.32 (d, J=1.01 Hz, 1H); LC-MS (ES) m/z=295.1 [M+H]

Provenance & Evidence