1-Methyl-4-pyrazole boronic acid pinacol ester is a reagent used for Suzuki-Miyaura cross-coupling reactions, transesterification reactions. It is involved in several reactions as a reagent for the preparation of aminothiazoles as γ-secretase modulators,amino-pyrido-indol-carboxamides, as potential JAK2 inhibitors for myeloproliferative disorders therapy, pyridine derivatives as TGF-β1 and active A signaling inhibitors and MK-2461 analogs as inhibitors of c-Met kinase for the treatment of cancer.
To the solution of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (0.40 g, 2.06 mmol) in THF (10 mL) was added NaH (0.1.00 g, 4.12 mmol) followed by methyl iodide (0.25 mL, 4.12 mmol) at 0° C and the reaction mixture was stirred at ambient temperature for 4 hr. The reaction was quenched with saturated NH4Cl solution (20 mL) and extracted with ethyl acetate (2 x 50 mL). The combined organic layers were washed with brine (20 mL), dried over sodium sulfate, and distilled under reduced pressure to obtain 1-Methyl-4-pyrazole boronic acid pinacol ester.