5-Chlorosalicylic Acid → 4,4'-Dihydroxybiphenyl-3,3'-dicarboxylic acid

HRID 232245Notes

Reaction equation

HRID 232245 reaction equation
[OH:1][C:2]1[CH:10]=[CH:9][C:8](Cl)=[CH:7][C:3]=1[C:4]([OH:6])=[O:5]>[OH-].[Na+].[Pd]>[OH:1][C:2]1[CH:10]=[CH:9][C:8]([C:8]2[CH:9]=[CH:10][C:2]([OH:1])=[C:3]([C:4]([OH:6])=[O:5])[CH:7]=2)=[CH:7][C:3]=1[C:4]([OH:6])=[O:5]

Participants

4

Reactant 1

HCID 94475-Chlorosalicylic Acid

Product 1

HCID 109346364,4'-Dihydroxybiphenyl-3,3'-dicarboxylic acidYield 80%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 14798Sodium HydroxideSolvent

Conditions

Temperature
120 °C

Procedure

2-hydroxy 5-chlorobenzoic acid (3.4 g, 20 mmol) was dissolved in 45 cm3 of a sodium hydroxide solution (10% w/v) and palladium on charcoal (10%, 0.5 g) was added. The mixture was placed in a glass liner in an autoclave which was flushed thoroughly with carbon monoxide, then pressurised with carbon monoxide to 2 MNm-2 and heated to 120° C. with stirring for three hours. The mixture was then allowed to cool, the catalyst removed by filtration, and the product precipitated from the aqueous solution by acidification to pH1 with 1M hydrochloric acid. The coupled product (4,4'-dihydroxybiphenyl 3,3'-dicarboxylic acid) was obtained in 80% yield.

Workup

  1. customwas flushed thoroughly with carbon monoxide
  2. temperatureto cool
  3. customthe catalyst removed by filtration
  4. customthe product precipitated from the aqueous solution by acidification to pH1 with 1M hydrochloric acid

Sources & evidence

ORD record
ord-213558fc03db4d83888ce9827233321a
Source dataset
uspto-grants-1989_07
Patent number
US04851538

Reaction notes

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