Thiophenol → 5-Phenylthiophene-3-carboxylic acid

HRID 894237Notes

Reaction equation

HRID 894237 reaction equation
[C:1]1(S)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.Br[C:9]1[S:13][CH:12]=[C:11]([C:14]([OH:16])=[O:15])[CH:10]=1>CN(C)C=O>[C:1]1([C:9]2[S:13][CH:12]=[C:11]([C:14]([OH:16])=[O:15])[CH:10]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1

Participants

4

Reactant 2

HCID 7969ThiophenolHCID 120399785-Bromothiophene-3-carboxylic acid

Product 1

HCID 162272215-Phenylthiophene-3-carboxylic acid

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Conditions

Temperature
135 °C

Procedure

In an open flask, thiophenol (2.86 g., 13 mmoles), cuprous oxide (1.86 g., 13 mmoles) and dimethyl formamide (30 ml.) were combined and heated in a 135° C. oil bath. The reaction mixture was allowed to cool slightly, 5-bromothiophene-3-carboxylic acid [2.5 g., 13 mmoles; Fournari et al., Bull. Chim. Soc. Fr., 4115 (1967)] in 50 ml. of dimethylformamide was added, and the mixture refluxed for 2 days. The reaction mixture was cooled, clarified by filtration, the filtrate evaporated to an oil, the oil triturated with 1 N hydrochloric acid, and gummy solids recovered by filtration and taken up in 1 N sodium hydroxide. The basic solution was extracted with ether, reacidified with conc. hydrochloric acid, product recovered by filtration, triturated with hexane and refiltered (912 mg., m.p. 97°-100° C., m/e 220). Recrystallization from methanol/water afforded purified 5-phenylthiofuran-3-carboxylic acid (439 mg., m.p. 101°-103° C.).

Workup

  1. temperatureto cool slightly
  2. temperaturethe mixture refluxed for 2 days
  3. temperatureThe reaction mixture was cooled
  4. filtrationclarified by filtration
  5. customthe filtrate evaporated to an oil
  6. customthe oil triturated with 1 N hydrochloric acid, and gummy solids
  7. filtrationrecovered by filtration
  8. extractionThe basic solution was extracted with ether
  9. filtrationrecovered by filtration
  10. customtriturated with hexane
  11. customRecrystallization from methanol/water
  12. customafforded
  13. custompurified 5-phenylthiofuran-3-carboxylic acid (439 mg., m.p. 101°-103° C.)

Sources & evidence

ORD record
ord-f8b459e4680841b49feeacc8d44c1dd2
Source dataset
uspto-grants-1981_08
Patent number
US04282246

Reaction notes

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