Sodium Hydroxide → 3-(4-Bromophenyl)-2-methylpropanoic acid

HRID 1107497Notes

Reaction equation

HRID 1107497 reaction equation
[OH-].[Na+].[Br:3][C:4]1[CH:9]=[CH:8][C:7]([CH2:10][CH:11]([C:17](OCC)=O)[C:12]([O:14]CC)=[O:13])=[CH:6][CH:5]=1>O.C(O)C>[Br:3][C:4]1[CH:5]=[CH:6][C:7]([CH2:10][CH:11]([CH3:17])[C:12]([OH:14])=[O:13])=[CH:8][CH:9]=1

Participants

5

Reactant 2

HCID 14798Sodium HydroxideHCID 10860456Diethyl 2-(4-bromobenzyl)malonate

Product 1

HCID 217141913-(4-Bromophenyl)-2-methylpropanoic acidYield 82.2%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 962WaterSolvent

Conditions

Temperature
200 °C

Procedure

A solution of sodium hydroxide (175 g) in water (800 ml) was added to a solution of diethyl (4-bromophenyl)methylmalonate (150 g) in ethanol (850 ml) and the mixture was heated under reflux for 9 hours. Volatile material was removed by evaporation and the residue was dissolved in a solution of sodium hydroxide (130 g) in water (250 ml). The solution was heated under reflux for 2.5 hours, filtered through a bed of diatomaceous earth and the filtrate was acidified with 6M sulphuric acid. The mixture was extracted with ether (4×500 ml) and the extracts were dried (MgSO4). The solution was concentrated and the residue was heated at 200° C. until evolution of carbon dioxide ceased. The residue was dissolved in 1M sodium hydroxide solution (500 ml) and the solution was acidified with 6M sulphuric acid. The mixture was extracted with ether (4×500 ml) and the extracts were dried (MgSO4). The solvent material was removed by evaporation to give 3-(4-bromophenyl)-2-methylpropionic acid (91 g), m.p. 72-73° C.; 1H NMR (d6 -DMSO): 1.0 (d, 3H), 2.05-2.15 (m, 2H), 2.85-2.9 (m, 1H), 7.1 (d, 2H), 7.4 (d, 2H).

Workup

  1. temperaturethe mixture was heated
  2. temperatureunder reflux for 9 hours
  3. customVolatile material was removed by evaporation
  4. dissolutionthe residue was dissolved in a solution of sodium hydroxide (130 g) in water (250 ml)
  5. temperatureThe solution was heated
  6. temperatureunder reflux for 2.5 hours
  7. filtrationfiltered through a bed of diatomaceous earth
  8. extractionThe mixture was extracted with ether (4×500 ml)
  9. dry with materialthe extracts were dried (MgSO4)
  10. concentrationThe solution was concentrated
  11. dissolutionThe residue was dissolved in 1M sodium hydroxide solution (500 ml)
  12. extractionThe mixture was extracted with ether (4×500 ml)
  13. dry with materialthe extracts were dried (MgSO4)
  14. customThe solvent material was removed by evaporation

Sources & evidence

ORD record
ord-e1ea5e91bb4847d6a4843c5c17bee021
Source dataset
uspto-grants-2000_05
Patent number
US06060475

Reaction notes

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