Potassium Carbonate → 5-ethynyl-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole

Participants

Reaction Steps

A 250-mL round-bottom flask equipped with a magnetic stir bar, a rubber septum, and a N2 inlet was charged with a solution of 1-(tetrahydro-2H-pyran-2-yl)-5-((trimethylsilyl)ethynyl)-1H-indazole (12.6 g, 42.2 mmol) in MeOH. To this solution, solid K2CO3 (0.58 g, 4.2 mmol) was added in one portion. The resulting mixture was stirred at room temperature for 4 h. Upon completion by TLC, the reaction mixture was filtered, concentrated, and purified by silica gel chromatography (0-10% ethyl acetate in hexanes) to give the title compound (4.7 g) as a pale yellow solid. 1H NMR (300 MHz, DMSO-d6): δ 8.13 (s, 1H), 7.96 (s, 1H), 7.75 (d, 1H), 7.47 (dd, 1H), 5.86 (dd, 1H), 4.10 (s, 1H), 3.90-3.86 (m, 1H), 3.78-3.68 (m, 1H), 2.43-2.32 (m, 1H), 2.06-1.93 (m, 2H), 1.81-1.66 (m, 1H), 1.60-1.50 (m, 2H).

Provenance & Evidence