Acetic Acid → (1-phenyl-1H-pyrazol-5-yl)boronic acid

HRID 1528073Notes

Reaction equation

HRID 1528073 reaction equation
[C:1]1([N:7]2[CH:11]=[CH:10][CH:9]=[N:8]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C([Li])CCC.[B:17](OC(C)C)([O:22]C(C)C)[O:18]C(C)C.C(O)(=O)C>C1COCC1>[C:1]1([N:7]2[C:11]([B:17]([OH:22])[OH:18])=[CH:10][CH:9]=[N:8]2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

6

Reactant 4

HCID 176Acetic AcidHCID 21531Triisopropyl borateHCID 707691-PhenylpyrazoleHCID 178418339Butyllithium

Product 1

HCID 59436217(1-phenyl-1H-pyrazol-5-yl)boronic acidYield 95.9%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 1-phenyl-1H-pyrazole (20.0 g) in THF (700 mL) was added dropwise n-butyllithium (2.5M hexane solution, 58.3 mL) at −78° C. under a nitrogen atmosphere, and the mixture was stirred at the same temperature for 30 min. To the reaction mixture was added triisopropyl borate (52.2 g) at −78° C., and the mixture was stirred at the same temperature for 1 hr, gradually allowed to be warmed to room temperature, and stirred at room temperature for 20 hr. The pH of the reaction mixture was adjusted to 5 with acetic acid (20 mL), and concentrated to give the title compound (25.0 g).

Workup

  1. stirringthe mixture was stirred at the same temperature for 1 hr
  2. stirringstirred at room temperature for 20 hr
  3. concentrationconcentrated

Sources & evidence

ORD record
ord-c7f9ac2e2514427e8d9bd545bb60409c
Source dataset
uspto-grants-2015_07
Patent number
US09090586B2

Reaction notes

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