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

HRID 333721

Reaction equation

HRID 333721 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>O1CCCC1>[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 tetrahydrofuran (700 mL) was added dropwise n-butyllithium (2.5M hexane solution, 58.3 mL) under a nitrogen atmosphere at −78° C., and the mixture was stirred at the same temperature for 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. The mixture was gradually warmed to room temperature, and stirred at room temperature for 20 hr. To the reaction mixture was added acetic acid (20 mL) to adjust to pH 5, and the mixture was 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. concentrationthe mixture was concentrated

Sources & evidence

ORD record
ord-0ce174f833cc450e97e671a0493ec689
Source dataset
uspto-grants-2014_11
Patent number
US08883788B2

Linked notes

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