Phosphorus oxychloride → 3-(2-(3-Chlorophenyl)ethyl)-2-pyridinecarbonitrile
Reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([CH2:8][CH2:9][C:10]2[C:11]([C:16]([NH:18]C(C)(C)C)=O)=[N:12][CH:13]=[CH:14][CH:15]=2)[CH:5]=[CH:6][CH:7]=1.P(Cl)(Cl)(Cl)=O>>[Cl:1][C:2]1[CH:3]=[C:4]([CH2:8][CH2:9][C:10]2[C:11]([C:16]#[N:18])=[N:12][CH:13]=[CH:14][CH:15]=2)[CH:5]=[CH:6][CH:7]=1Participants
Procedure
Heat a solution of the title compound of Preparative Example 1B, 3-[2-(3-chlorophenyl)ethyl]-N-(1,1-dimethylethyl)-2-pyridine carboxamide (175 g, 0.554 mole) in phosphorous oxychloride (525 mL, 863 g, 5.63 mole) and reflux for 3 hours. Determine completion of the reaction by thin layer chromatography. Remove any excess phosphorous oxychloride by distillation at reduced pressure and quench the reaction in a mixture of water and isopropanol. Bring to pH 5-7 by adding 50% aqueous NaOH solution while maintaining the temperature below 30° C. Filter the crystalline slurry of crude product and wash with water. Purify the crude product by slurrying the wet cake in hot isopropanol, and cool to 0°-5° C. Filter the product, wash with hexane and dry at a temperature below 50° C. to yield the title compound. (Yield: 118 g (HPLC purity 95.7%), m.p. 72° C.-73° C., 89.4% of theory).
Sources & evidence
- ORD record
- ord-67b9ae0fc29540f890527e7ccb203ca4
- Source dataset
- uspto-grants-1998_02
- Patent number
- US05714609
Reaction notes
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