2-Iodothiophene → 2-(Thien-2-ylethynyl)benzothiophene

HRID 1460988Notes

Reaction equation

HRID 1460988 reaction equation
C[Si](C)(C)[C:3]#[C:4][C:5]1[S:6][C:7]2[CH:13]=[CH:12][CH:11]=[CH:10][C:8]=2[CH:9]=1.O.O.O.[F-].C([N+](CCCC)(CCCC)CCCC)CCC.[F-].[K+].I[C:40]1[S:41][CH:42]=[CH:43][CH:44]=1>C(OCC)C>[S:41]1[CH:42]=[CH:43][CH:44]=[C:40]1[C:3]#[C:4][C:5]1[S:6][C:7]2[CH:13]=[CH:12][CH:11]=[CH:10][C:8]=2[CH:9]=1

Participants

6

Reactant 4

HCID 189212-IodothiopheneHCID 522689Potassium FluorideHCID 11726816Tetrabutylammonium Fluoride TrihydrateHCID 199814162-Trimethylsilylethynylbenzothiophene2×

Product 1

HCID 131937012-(Thien-2-ylethynyl)benzothiophene

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

The reaction mixture from Step A containing 2-trimethylsilylethynylbenzothiophene was stirred, and 4.96 grams (0.0157 mole) of tetrabutylammonium fluoride trihydrate and 10.1 grams (0.173 mole) of potassium fluoride were added. Upon completion of addition, the reaction mixture was stirred at ambient temperature for 4.5 hours. After this time 36.3 grams (0.173 mole) of 2-iodothiophene was added via syringe. Upon completion of addition, the reaction mixture was stirred at ambient temperature for 60 hours. After this time the reaction mixture was dissolved in diethyl ether and a small amount of methylene chloride, and it was washed with two portions of an aqueous solution of 10% ammonium chloride, one portion of water and one portion of an aqueous solution saturated with sodium chloride. The organic layer was dried with sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to a residue. The residue was subjected to column chromatography on silica gel. Elution was accomplished with hexane and 20% methylene chloride in hexane. The appropriate fractions were combined and concentrated under reduced pressure, yielding 35.1 grams of 2-(thien-2-ylethynyl)benzothiophene.

Workup

  1. additionUpon completion of addition
  2. additionUpon completion of addition
  3. stirringthe reaction mixture was stirred at ambient temperature for 60 hours
  4. washa small amount of methylene chloride, and it was washed with two portions of an aqueous solution of 10% ammonium chloride, one portion of water and one portion of an aqueous solution saturated with sodium chloride
  5. dry with materialThe organic layer was dried with sodium sulfate
  6. filtrationfiltered
  7. concentrationThe filtrate was concentrated under reduced pressure to a residue
  8. washElution
  9. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-d18929488ab649af9f0931ecc02c91c5
Source dataset
uspto-grants-1991_12
Patent number
US05073564

Reaction notes

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