Phthalic Acid → 2-(5-Bromo-2,4-dihydroxybenzoyl)benzoic acid

HRID 1784330Notes

Reaction equation

HRID 1784330 reaction equation
[Cl-].[Al+3].[Cl-].[Cl-].[C:5]1(=[O:15])[O:10][C:8](=[O:9])[C:7]2=[CH:11][CH:12]=[CH:13][CH:14]=[C:6]12.[Br:16][C:17]1[CH:23]=[CH:22][C:20]([OH:21])=[CH:19][C:18]=1[OH:24].C(O)(=O)C1C(=CC=CC=1)C(O)=O>ClCC(Cl)(Cl)Cl.C(OCC)(=O)C.ClCCl.[N+](C)([O-])=O>[Br:16][C:17]1[C:18]([OH:24])=[CH:19][C:20]([OH:21])=[C:22]([CH:23]=1)[C:8]([C:7]1[CH:11]=[CH:12][CH:13]=[CH:14][C:6]=1[C:5]([OH:10])=[O:15])=[O:9]

Participants

9

Reactant 4

HCID 1017Phthalic AcidHCID 6811Phthalic AnhydrideHCID 811054-BromoresorcinolHCID 6451240Aluminum(III) Chloride

Product 1

HCID 223157072-(5-Bromo-2,4-dihydroxybenzoyl)benzoic acid

Reagents, catalysts & solvents 4

HCID 6344DichloromethaneSolventHCID 6375NitromethaneSolventHCID 8857Ethyl AcetateSolventHCID 124181,1,1,2-TetrachloroethaneSolvent

Procedure

Aluminum chloride (8.48 g, 64 mmol) was added to a stirring suspension of phthalic anhydride (2.36 g, 16 mmol) in tetrachloroethane (40 mL) under nitrogen. Nitromethane (6 mL) was added to dissolve the reactants. 4-Bromoresorcinol (3 g, 16 mmol) was added and the mixture continued to stir under nitrogen. The reaction was monitored by high performance liquid chromatography (HPLC) over a period of 2 hours. It was observed that the reaction had ceased within the first 30 minutes, with starting materials remaining. The solution was diluted with ethyl acetate (˜150 mL) and washed with 1 M hydrochloric acid (2×100 mL). The product was extracted from the organic layer into a saturated solution of sodium bicarbonate in water (200 mL). The basic aqueous phase was acidified with 3M hydrochloric acid to a pH of 5. The product was extracted from the aqueous phase into ethyl acetate (150 mL), washed with brine (2×100 mL), dried over magnesium sulfate and concentrated to give an orange oil which solidified upon standing for about 10 minutes. The solid was slurried in dichloromethane (20 mL) and filtered to give a mixture of the desired product and phthalic acid. Slurrying in water (20 mL) followed by filtration gave the desired product as a beige powder (1.72 g, 5.1 mmol, 32% yield).

Workup

  1. dissolutionto dissolve the reactants
  2. customhad ceased within the first 30 minutes, with starting materials
  3. washwashed with 1 M hydrochloric acid (2×100 mL)
  4. extractionThe product was extracted from the organic layer into a saturated solution of sodium bicarbonate in water (200 mL)
  5. extractionThe product was extracted from the aqueous phase into ethyl acetate (150 mL)
  6. washwashed with brine (2×100 mL)
  7. dry with materialdried over magnesium sulfate
  8. concentrationconcentrated
  9. customto give an orange oil which
  10. waitupon standing for about 10 minutes
  11. filtrationfiltered
  12. customto give

Sources & evidence

ORD record
ord-4dfb463b99444444863b23ce4c1004a4
Source dataset
uspto-grants-2009_03
Patent number
US07504360B2

Reaction notes

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