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| | 1-Ethyl-1H-pyrazole-4-boronic acid, pinacol ester Basic information |
| Product Name: | 1-Ethyl-1H-pyrazole-4-boronic acid, pinacol ester | | Synonyms: | 1-ethyl-4-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole;1-Ethyl-1H-pyrazole-4-boronic acid, pinacol ester;3-hydroxy-2,3-dimethylbutan-2-yl hydrogen (1-ethyl-1H-pyrazol-4-yl)boronate;1-Ethylpyrazole-4-boronic Acid Pinacol Ester;1H-Pyrazole, 1-ethyl-4-(4,4,5,5-tetraMethyl-1,3,2-dioxaborolan-2-yl)-;1-Eth;2-(1-Ethyl-1H-pyrazol-4yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane;1-Ethyl-1H-pyrazole-4-boronic acid, pina | | CAS: | 847818-70-6 | | MF: | C11H19BN2O2 | | MW: | 222.09 | | EINECS: | | | Product Categories: | | | Mol File: | 847818-70-6.mol |  |
| | 1-Ethyl-1H-pyrazole-4-boronic acid, pinacol ester Chemical Properties |
| Melting point | 44-49°C | | Boiling point | 322.6±15.0 °C(Predicted) | | density | 1.04±0.1 g/cm3(Predicted) | | refractive index | 1.48 | | storage temp. | under inert gas (nitrogen or Argon) at 2-8°C | | pka | 2.11±0.10(Predicted) | | form | clear liquid | | color | Colorless to Almost colorless | | InChI | InChI=1S/C11H19BN2O2/c1-6-14-8-9(7-13-14)12-15-10(2,3)11(4,5)16-12/h7-8H,6H2,1-5H3 | | InChIKey | UGCRHVPUHAXAAE-UHFFFAOYSA-N | | SMILES | N1(CC)C=C(B2OC(C)(C)C(C)(C)O2)C=N1 | | CAS DataBase Reference | 847818-70-6 |
| Hazard Codes | Xi | | Risk Statements | 36/37/38 | | Safety Statements | 26 | | WGK Germany | 3 | | HS Code | 2933199090 | | Storage Class | 11 - Combustible Solids | | Hazard Classifications | Eye Irrit. 2
Skin Irrit. 2
STOT SE 3 |
| | 1-Ethyl-1H-pyrazole-4-boronic acid, pinacol ester Usage And Synthesis |
| Synthesis | To a solution of N,N-dimethylformamide (DMF, 10 mL) of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (1.0 g, 5.2 mmol) was added cesium carbonate (2.5 g, 7.7 mmol) and ethyl iodide (1.2 mL, 15 mmol). The reaction mixture was stirred at room temperature for 12 hours. After the reaction was completed, the reaction mixture was diluted with water (30 mL). The aqueous phase was extracted with dichloromethane (DCM, 30 mL x 3). The organic layers were combined and dried over anhydrous sodium sulfate (Na2SO4) and subsequently concentrated under reduced pressure. The residue was purified by silica gel column chromatography using petroleum ether (PE)/ethyl acetate (EtOAc) (2:1, v/v) as eluent to afford the colorless oily product 1-ethyl-1H-pyrazole-4-boronic acid pinacol ester (880 mg, 77% yield). Mass spectrometric (MS) analysis (electrospray ionization, cation mode) showed m/z: 223.25 [M + 1]+. | | References | [1] Patent: WO2016/615, 2016, A1. Location in patent: Paragraph 00655
[2] Patent: EP1798229, 2007, A1. Location in patent: Page/Page column 130
[3] Patent: US2010/240634, 2010, A1. Location in patent: Page/Page column 67-68
[4] Patent: WO2018/102452, 2018, A2. Location in patent: Paragraph 425; 426
[5] Bioorganic and Medicinal Chemistry Letters, 2008, vol. 18, # 19, p. 5299 - 5302 |
| | 1-Ethyl-1H-pyrazole-4-boronic acid, pinacol ester Preparation Products And Raw materials |
| Raw materials | Bis(pinacolato)diboron-->4-Pyrazoleboronic acid pinacol ester-->1-Azetidinecarboxylic acid, 3-[4-[6-[(6-methyl-1,2,4-triazolo[4,3-b]pyridazin-3-yl)thio]-3-quinolinyl]-1H-pyrazol-1-yl]-, 1,1-dimethylethyl ester-->Iodoethane-->4-Bromo-1-ethyl-1H-pyrazole-->Cesium carbonate-->N,N-Dimethylformamide | | Preparation Products | 4-(4,4,5,5-tetraMethyl-1,3,2-dioxaborolan-2-yl)-1-(2,2,2-trifluoroethyl)-1H-pyrazole |
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