Sodium Carbonate → 4-Bromo-1-(1,1-dimethylethyl)-1H-pyrazole

HRID 599311Notes

Reaction equation

HRID 599311 reaction equation
C([O-])([O-])=O.[Na+].[Na+].[C:7]([N:11]1[CH:15]=[CH:14][CH:13]=[N:12]1)([CH3:10])([CH3:9])[CH3:8].[Br:16]Br>C(Cl)Cl>[Br:16][C:14]1[CH:13]=[N:12][N:11]([C:7]([CH3:10])([CH3:9])[CH3:8])[CH:15]=1

Participants

5

Reactant 3

HCID 10340Sodium CarbonateHCID 24408BromineHCID 134698151-tert-Butyl-1H-pyrazole

Product 1

HCID 532168984-Bromo-1-(1,1-dimethylethyl)-1H-pyrazoleYield 85%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a suspension of Na2CO3 (36 g, 339 mmol) in CH2Cl2 (300 mL) was added 1-t-butyl-1H-pyrazole from Example B19 (21 g, 170 mmol) and Br2 (9 mL), and the resulting mixture was stirred at RT overnight. The solid was removed by filtration and the filter cake was washed with CH2Cl2. The filtrates were washed with water and brine, dried (MgSO4), and concentrated to give crude 4-bromo-1-t-butyl-1H-pyrazole (29 g, 85%), used without further purification. 1H NMR (300 MHz, CDCl3): δ 7.49 (s, 1 H), 7.45 (s, 1 H), 1.53 (s, 9 H); MS (ESI) m/z: 203 [M+H]+.

Workup

  1. customThe solid was removed by filtration
  2. washthe filter cake was washed with CH2Cl2
  3. washThe filtrates were washed with water and brine
  4. dry with materialdried (MgSO4)
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-ee725fc8e0fb440abc1da832549d77c4
Source dataset
uspto-grants-2011_03
Patent number
US07897762B2

Reaction notes

Loading…