Hydrogen Bromide → Benzoic Acid

HRID 27466

Reaction equation

HRID 27466 reaction equation
C([O:3][C:4](=[O:12])[C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=1O)C.Br.OC1C=CC=CC=1C(O)=O.C(O)C.Cl.[H-].[Na+].C(Br)C=C>CN(C=O)C>[C:4]([OH:12])(=[O:3])[C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1

Participants

8

Reactant 6

HCID 260Hydrogen BromideHCID 338Salicylic AcidHCID 7841Allyl bromideHCID 8365Ethyl SalicylateHCID 24758Sodium hydrideHCID 21887872Ethanol hydrochloride

Product 1

HCID 243Benzoic Acid

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

13.6 g of 4-(2-<5-chloro-2-methoxy-benzamido>-ethyl)-2-hydroxy-benzoic acid ethyl ester, M.p. 88°-89° C., (prepared by treatment of 4-(2-aminoethyl)-2-methoxy-benzoic acid. HCl with hydrobromic acid/glacial acetic acid, reaction of the resulting 4-(2-<5-chloro-2-methoxy-benzamido>-ethyl)-2-hydroxy-benzoic acid with ethanol/HCl) were dissolved in 75 ml of DMF and combined with 1.2 g of sodium hydride/80% strength in white oil. The whole was stirred for half an hour, 4.4 g of allyl bromide were added and stirring was continued for 4 hours at 65° C. The dimethylformamide was then eliminated by distillation under reduced pressure, the residue was dissolved in ether, washed with sodium hydroxide solution and water, the ether solution was concentrated by evaporation and the residue was hydrolyzed by heating with 100 ml of 10% sodium hydroxide solution in the presence of a small amount of ethanol. After cooling, the solution was acidified, the substance that had precipitated was re-precipitated from ammonia with the aid of charcoal and then crystallized from dilute methanol. The 2-allyloxy-4-(2-<5-chloro-2-methoxy-benzamido>-ethyl)-benzoic acid so obtained was found to melt at 122°-123° C.

Workup

  1. stirringstirring
  2. distillationThe dimethylformamide was then eliminated by distillation under reduced pressure
  3. dissolutionthe residue was dissolved in ether
  4. washwashed with sodium hydroxide solution and water
  5. concentrationthe ether solution was concentrated by evaporation
  6. temperatureby heating with 100 ml of 10% sodium hydroxide solution in the presence of a small amount of ethanol
  7. temperatureAfter cooling
  8. customthe substance that had precipitated
  9. customwas re-precipitated from ammonia with the aid of charcoal
  10. customcrystallized from dilute methanol

Sources & evidence

ORD record
ord-33c62ca187fe495582433e380d245f61
Source dataset
uspto-grants-1980_09
Patent number
US04221815

Linked notes

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