Picolinic acid → HCID 70817475, Verbindung

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of 7-bromo-imidazo[1,2-a]pyridine (600 mg, 3.0 mmol) and diethyl malonate (0.93 mL, 6.1 mmol) in dry dioxane (15 mL) was added cesium carbonate (3 gm, 9.1 mmol). Argon was bubbled through the mixture for 10 minutes and then copper (I) iodide (116 mg, 0.61 mmol) and picolinic acid (150 mg, 1.22 mmol) were added. The resultant mixture was heated in a sealed tube at 130° C. for 24 hours. The reaction mixture was cooled to room temperature, quenched with water (10 mL) and extracted with EtOAc (3×20 mL). The combined organic layers were washed with water (2×10 mL), brine (10 mL), dried over sodium sulphate, filtered and concentrated under reduced pressure. The crude material was purified by silica gel column chromatography eluting with a gradient of dichloromethane:methanol 100:0 to 98:2 to afford the title compound as an off-white gum in 29% yield, 180 mg.

Herkunft & Nachweise