Triisopropyl borate → (5-benzyl-1-methyl-1H-pyrazol-4-yl)boronic acid

HRID 1778202Notes

Reaction equation

HRID 1778202 reaction equation
[CH2:1]([C:8]1[N:12]([CH3:13])[N:11]=[CH:10][C:9]=1Br)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[B:15](OC(C)C)([O:20]C(C)C)[O:16]C(C)C.[Li]CCCC>C1COCC1.CCCCCC>[CH2:1]([C:8]1[N:12]([CH3:13])[N:11]=[CH:10][C:9]=1[B:15]([OH:20])[OH:16])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

6

Reactant 3

HCID 21531Triisopropyl borateHCID 867185475-Benzyl-4-bromo-1-methyl-1H-pyrazoleHCID 178418339Butyllithium

Product 1

HCID 86718548(5-benzyl-1-methyl-1H-pyrazol-4-yl)boronic acidYield 39%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 8058HexaneSolvent

Conditions

Temperature
-78 °C

Procedure

5-Benzyl-4-bromo-1-methyl-1H-pyrazole (0.27 g; 1.06 mmol) is dissolved in 5.0 ml anhydrous THF and cooled down to −78° C. Afterwards triisopropyl borate (0.46 ml; 2.01 mmol) and n-BuLi; 1.6 mol/l in Hexane; (0.69 ml; 1.11 mmol) are added. It is stirred for 1 hour within the desired product is formed. It is warmed to 25° C. and quenched with water. It is purified with reverse phase chromatography by using basic conditions.

Workup

  1. addition(0.69 ml; 1.11 mmol) are added

Sources & evidence

ORD record
ord-b3a39b6708e545159593533c6824bbd3
Source dataset
uspto-grants-2016_02
Patent number
US09266891B2

Reaction notes

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