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

Temperatur

90 °C

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:

1. customwas purged with argon
2. customthe mixture was purged with argon again
3. temperatureAfter cooled to room temperature
4. filtrationthe mixture was filtered
5. concentrationthe filtrate was concentrated under reduced pressure
6. customThe residue was purified by column chromatography (Purif, silica gel, hexane to 70:30 hexane/EtOAc)

ORD-Eintrag

ord-823b86513d974a7690a293db01e594fe

Quelldatensatz

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08691828B2