Trichloroacetyl chloride → 4-(trichloroacetyl)-1H-pyrrole-2-carbonitrile
Reaction equation
[Cl:1][C:2]([Cl:7])([Cl:6])[C:3](Cl)=[O:4].[Cl-].[Cl-].[Cl-].[Al+3].[C:12]([C:14]1[NH:15][CH:16]=[CH:17][CH:18]=1)#[N:13]>ClCCl.C(OCC)(=O)C>[Cl:1][C:2]([Cl:7])([Cl:6])[C:3]([C:17]1[CH:18]=[C:14]([C:12]#[N:13])[NH:15][CH:16]=1)=[O:4]Participants
Procedure
Trichloracetyl chloride (44.4 g, 27.3 mL, 244 mmol) in dichloromethane (75 mL) was added over 20 min to a mechanically stirred suspension of aluminum trichloride (54.3 g, 407 mmol) in dichloromethane (150 mL). The resulting mixture was stirred for 30 min, and then 2-cyanopyrrole (15.0 g, 163 mmol) in dichloromethane (75 mL) was added over 30 min. The reaction was heated at reflux for 5 h and then allowed to cool. The reaction was diluted with ethyl acetate (600 mL) and then quenched slowly with water (300 mL). The layers were separated and then the organic layer was washed with water and brine, dried (magnesium sulfate) and evaporated under reduced pressure to afford a quantitative yield of desired product (39.0 g, 100%) containing trace impurities. This material was used in the next step without further purification. 1H NMR (DMSO-d6) δ 8.14 (s, 1H), 7.55 (s, 1H).
Workup
- temperatureThe reaction was heated
- temperatureat reflux for 5 h
- temperatureto cool
- customquenched slowly with water (300 mL)
- customThe layers were separated
- washthe organic layer was washed with water and brine
- dry with materialdried (magnesium sulfate)
- customevaporated under reduced pressure
Sources & evidence
- ORD record
- ord-38241251c7ca410398662e4acae52fc8
- Source dataset
- uspto-grants-2012_03
- Patent number
- US08133995B2
Reaction notes
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