Potassium Acetate → (5-formyl-1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-pyrazol-4-yl)boronic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-bromo-1-[[2-(trimethylsilyl)ethoxy]methyl]-1H-pyrazole-5-carbaldehyde (2.00 g, 6.55 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane (1.75 g, 6.88 mmol), potassium acetate (1.93 g, 19.7 mmol) and 1,2-dimethoxyethane (40 mL) was purged with argon. Then, 1,1′-bis(diphenylphosphino)ferrocenepalladium (II) dichloride dichloromethane adduct (0.535 g, 0.655 mmol) was added, and the mixture was purged with argon again. The mixture was stirred at 90° C. overnight. After cooled to room temperature, the mixture was filtered, and the filtrate was concentrated under reduced pressure. The residue was purified by column chromatography (Purif, silica gel, hexane to 70:30 hexane/EtOAc) to afford the title compound (571 mg, 25%) as a colorless oil:

Provenance & Evidence