2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → 1-Benzothiophene-4-carbonitrile

HRID 2183613Notes

Reaction equation

HRID 2183613 reaction equation
[S:1]1[CH:5]=[CH:4][C:3]2[C:6]([C:10]#[N:11])=[CH:7][CH2:8][CH2:9][C:2]1=2.ClC1C(=O)C(C#N)=C(C#N)C(=O)C=1Cl>C1(C)C=CC=CC=1>[S:1]1[CH:5]=[CH:4][C:3]2[C:6]([C:10]#[N:11])=[CH:7][CH:8]=[CH:9][C:2]1=2

Participants

4

Reactant 2

HCID 67752,3-Dichloro-5,6-dicyano-1,4-benzoquinoneHCID 224741326,7-Dihydrobenzo[b]thiophene-4-carbonitrile

Product 1

HCID 218165751-Benzothiophene-4-carbonitrileYield 64.9%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
80 °C

Procedure

A mixture of the crude 6,7-dihydrobenzo[b]thiophene-4-carbonitrile (88.3 g), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (120 g) and toluene (750 ml) was stirred at 80° C. for 2 hours then allowed to cool to ambient temperature. The resulting solid was removed by filtration and washed with toluene (500 ml). The filtrate and washings were combined, the solvent was removed in vacuo, and the residue was purified by Biotage flash chromatography over silica using 3-5% mixtures of ethyl acetate in petroleum ether (b.p. 60-80° C.) as eluant. Appropriate fractions were combined and the solvents were removed in vacuo to leave benzo[b]thiophene-4-carbonitrile (56.6 g) as a pale yellow solid which was used without further purification.

Workup

  1. temperatureto cool to ambient temperature
  2. customThe resulting solid was removed by filtration
  3. washwashed with toluene (500 ml)
  4. customthe solvent was removed in vacuo
  5. customthe residue was purified by Biotage flash chromatography over silica using 3-5% mixtures of ethyl acetate in petroleum ether (b.p. 60-80° C.) as eluant
  6. customthe solvents were removed in vacuo

Sources & evidence

ORD record
ord-6da50344f6664f3cbf76544af399b341
Source dataset
uspto-grants-2005_05
Patent number
US06900216B2

Reaction notes

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