Sodium hydride → 1-(2-Methoxyethyl)-1H-pyrazole-4-boronic acid, pinacol ester

HRID 57526

Reaction equation

HRID 57526 reaction equation
[CH3:1][C:2]1([CH3:14])[C:6]([CH3:8])([CH3:7])[O:5][B:4]([C:9]2[CH:10]=[N:11][NH:12][CH:13]=2)[O:3]1.Br[CH2:16][CH2:17][O:18][CH3:19].[H-].[Na+]>C1COCC1>[CH3:19][O:18][CH2:17][CH2:16][N:12]1[CH:13]=[C:9]([B:4]2[O:5][C:6]([CH3:7])([CH3:8])[C:2]([CH3:14])([CH3:1])[O:3]2)[CH:10]=[N:11]1

Participants

5

Reactant 3

HCID 24758Sodium hydrideHCID 809722-Bromoethyl methyl etherHCID 27740104-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

Product 1

HCID 112304911-(2-Methoxyethyl)-1H-pyrazole-4-boronic acid, pinacol ester

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A mixture of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (200 mg, 1.03 mmol), 1-bromo-2-methoxyethane (280 mg, 2.01 mmol), and NaH (200 mg, 4 mmol) in THF (15 mL) was stirred at reflux for 24 hours, cooled to the ambient temperature, and concentrated in vacuo. The residue was treated with HCl(aq) and extracted with EtOAc. The insoluble solid was removed by filtration, and the organic solution was concentrated to give the title compound. MS (m/z): 253 (M+H)+.

Workup

  1. temperatureat reflux for 24 hours
  2. concentrationconcentrated in vacuo
  3. additionThe residue was treated with HCl(aq)
  4. extractionextracted with EtOAc
  5. customThe insoluble solid was removed by filtration
  6. concentrationthe organic solution was concentrated

Sources & evidence

ORD record
ord-2910dcc4677c4e7985ca0045b2de53aa
Source dataset
uspto-grants-2016_09
Patent number
US09434726B2

Linked notes

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