Uses
1-Methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is patented as a reagent to synthesize quinoxaline derivatives or heterocyclylamine derivatives as PI3 kinase inhibitors.
Synthesis
General procedure for the synthesis of 1-methylpyrazole-3-boronic acid pinacol ester from 3-bromo-1-methylpyrrole and bis(pinacolato)diboronic acid: firstly, compound 701 (3-bromo-1-methylpyrrole, 0.2 g, 1.24 mmol) was dissolved in 5 mL of 1,4-dioxane. Subsequently, bis(pinacolato)diboron (0.378 g, 1.49 mmol), potassium acetate (0.365 g, 3.72 mmol), and [1,1-bis(diphenylphosphino)ferrocene]palladium chloride dichloromethane complex (0.11 g, 0.124 mmol) were added to this solution. The reaction mixture was heated to 95 °C under nitrogen protection and kept at this temperature for 5 hours of reaction. After completion of the reaction, the mixture was cooled to room temperature. To the reaction mixture was added 15 mL of water, stirred for 1 hour and filtered to give 0.114 g of solid product, 1-methylpyrazole-3-boronic acid pinacol ester. The yield was 44.19%.
References
[1] Patent: EP3072893, 2016, A1. Location in patent: Paragraph 0394; 0395
[2] Patent: EP2818473, 2014, A1. Location in patent: Paragraph 0578
