Water → 5-(2-Hydroxyphenyl)-thiophene-2-carboxylic acid

HRID 896468Notes

Reaction equation

HRID 896468 reaction equation
Br[C:2]1[S:6][C:5]([C:7]([OH:9])=[O:8])=[CH:4][CH:3]=1.[C:10]1([OH:16])[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1.C([O-])([O-])=O.[Na+].[Na+].O>C1COCC1.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[OH:16][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][C:11]=1[C:2]1[S:6][C:5]([C:7]([OH:9])=[O:8])=[CH:4][CH:3]=1

Participants

7

Reactant 4

HCID 962WaterHCID 996PhenolHCID 10340Sodium CarbonateHCID 3491155-Bromothiophene-2-carboxylic acid

Product 1

HCID 223508435-(2-Hydroxyphenyl)-thiophene-2-carboxylic acidYield 83%

Reagents, catalysts & solvents 2

HCID 178418397HCID 178418397, compoundCatalystHCID 8028TetrahydrofuranSolvent

Procedure

Tetrakis(triphenylphosphine)palladium(0) (133 mg, 0.12 mmol) is added to a solution of 5-bromothiophene-2-carboxylic acid (850 mg, 4.6 mmol) in degassed THF (10 mL). The resulting solution is stirred for 5 min and then 2-(4,4,5,5-tetramethyl)-1,3,2-dioxaborolan-2-yl) phenol (1 g, 4.6 mmol) is added followed by aqueous Na2CO3 (2M, 6.9 mL). The mixture is heated at reflux overnight. The reaction mixture is allowed to cool, poured into water (50 mL), and washed with ether (3×50 mL). The aqueous layer is acidified with concentrated HCl to pH<2. The resulting precipitate is collected by filtration, washed with water and dried in vacuo to yield 5-(2-hydroxyphenyl)-thiophene-2-carboxylic acid (761 mg, 83%). MS for C11H7O3S (ESI) (M−H)+ m/z 219.

Workup

  1. temperatureThe mixture is heated
  2. temperatureat reflux overnight
  3. temperatureto cool
  4. washwashed with ether (3×50 mL)
  5. filtrationThe resulting precipitate is collected by filtration
  6. washwashed with water
  7. customdried in vacuo

Sources & evidence

ORD record
ord-04c6fe9e4ab943618fb9d2090c541446
Source dataset
uspto-grants-2005_07
Patent number
US06919359B2

Reaction notes

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