Water → 1-(Pyridin-2-ylmethyl)-1H-pyrazole-4-boronic acid, pinacol ester

HRID 2362692Notes

Reaction equation

HRID 2362692 reaction equation
[H-].[Na+].[CH3:3][C:4]1([CH3:16])[C:8]([CH3:10])([CH3:9])[O:7][B:6]([C:11]2[CH:12]=[N:13][NH:14][CH:15]=2)[O:5]1.Cl.Cl[CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][N:21]=1.O>CN(C)C=O.[I-].C([N+](CCCC)(CCCC)CCCC)CCC.C(OCC)(=O)C>[CH3:3][C:4]1([CH3:16])[C:8]([CH3:9])([CH3:10])[O:7][B:6]([C:11]2[CH:15]=[N:14][N:13]([CH2:19][C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][N:21]=3)[CH:12]=2)[O:5]1

Participants

8

Reactant 4

HCID 962WaterHCID 23392Picolyl chloride hydrochlorideHCID 24758Sodium hydrideHCID 27740104-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

Product 1

HCID 179991861-(Pyridin-2-ylmethyl)-1H-pyrazole-4-boronic acid, pinacol ester

Reagents, catalysts & solvents 3

HCID 67553Tetrabutylammonium IodideCatalystHCID 6228DimethylformamideSolvent2×HCID 8857Ethyl AcetateSolvent

Procedure

To a suspension of sodium hydride (0.096 ml, 5.15 mmol) in N,N-dimethylformamide (8.59 ml) was added 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (0.5 g, 2.58 mmol). After 0.5 hours, 2-chloromethylpyridine hydrochloride salt (0.423 g, 2.58 mmol), and tetrabutylammonium iodide (0.095 g, 0.258 mmol) were added as solution in N,N-dimethylformamide (2 mL). The reaction was cooled to room temperature and diluted with ethyl acetate (10 mL). Water (10 mL) was added, and the layers were separated. The aqueous layer was extracted with additional ethyl acetate (2×30 mL). The combined organics were washed with water, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give the title compound, which was used without further purification. MS ESI(+) m/z 285.9 [M+H]+.

Workup

  1. customthe layers were separated
  2. extractionThe aqueous layer was extracted with additional ethyl acetate (2×30 mL)
  3. washThe combined organics were washed with water
  4. dry with materialdried with anhydrous sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-d9e9a43ed9d24e6bbebed1568ea5b14e
Source dataset
uspto-grants-2014_04
Patent number
US08691810B2

Reaction notes

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