Identification | Back Directory | [Name]
3-Methyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-pyrazole | [CAS]
936250-20-3 | [Synonyms]
5-Methylpyr 3-Methyl-4-(4 5-Methylpyrazole-4-boronic acid, pinacol ester 3-Methyl-4-pyrazole boronic acid pinacol ester 3-Methyl-1H-pyrazole-4-boronic acid pinacol ester 3-Methyl-1H-pyrazole-4-boronicacid,pinacolester96% (3-METHYL-1H-PYRAZOL-4-YL)BORONIC ACID PINACOL ESTER 3-Methyl-1H-pyrazole-4-boronic acid pinacol ester 97% 5-Methyl-1H-pyrazole-4-boronic acid, pinacol ester 96% 3-Methyl-4-(tetraMethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole 3-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-... 5-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole 3-Methyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-pyrazole 1H-Pyrazole, 3-Methyl-4-(4,4,5,5-tetraMethyl-1,3,2-dioxaborolan-2-yl)- 3-hydroxy-2,3-dimethylbutan-2-yl hydrogen (3-methyl-1H-pyrazol-4-yl)boronate | [Molecular Formula]
C10H17BN2O2 | [MDL Number]
MFCD08690235 | [MOL File]
936250-20-3.mol | [Molecular Weight]
208.065 |
Chemical Properties | Back Directory | [Melting point ]
129-134℃ | [Boiling point ]
350.3±30.0 °C(Predicted) | [density ]
1.07±0.1 g/cm3(Predicted) | [storage temp. ]
Inert atmosphere,2-8°C | [form ]
solid | [pka]
13.92±0.50(Predicted) | [color ]
White | [InChI]
InChI=1S/C10H17BN2O2/c1-7-8(6-12-13-7)11-14-9(2,3)10(4,5)15-11/h6H,1-5H3,(H,12,13) | [InChIKey]
MSJAEFFWTBMIKT-UHFFFAOYSA-N | [SMILES]
N1C=C(B2OC(C)(C)C(C)(C)O2)C(C)=N1 | [CAS DataBase Reference]
936250-20-3 |
Hazard Information | Back Directory | [Chemical Properties]
Solid | [Uses]
suzuki reaction | [Synthesis]
The general procedure for the synthesis of 3-methylpyrazole-4-boronic acid pinacol ester from 4-bromo-3-methyl-1H-pyrazole-1-carboxylic acid tert-butyl ester and pinacol ester of bis-boronic acid is as follows:
1. tert-butyl 4-bromo-3-methyl-1H-pyrazole-1-carboxylate (0.48 g, 1.84 mmol), bis(pinacolato)diboron (0.535 g, 2.1 mmol), dichloro[1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (0.156 g, 0.19 mmol), and potassium acetate ( 0.56 g, 5.7 mmol) were added sequentially to a sealed tube.
2. Add DMSO (5 mL) as a solvent to ensure that all solids are fully dissolved.
3. Flush the reaction system with nitrogen to remove oxygen and subsequently seal the reaction tube.
4. Heat the reaction mixture to 90°C and maintain this temperature for 18 hours. 5.
5. Upon completion of the reaction, the solvent was removed and the crude product was purified by silica gel column chromatography (eluent: 50% ethyl acetate in hexane solution) to afford the target compound, 3-methylpyrazole-4-boronic acid pinacol ester (0.2 g, 50% yield).
6. The structure of the product was confirmed by mass spectrometry (ESI), m/z 209.1 [M + 1]+. | [References]
[1] Patent: WO2008/51493, 2008, A2. Location in patent: Page/Page column 181 [2] Patent: US2013/123281, 2013, A1. Location in patent: Paragraph 0127 |
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