Benzene → 4-cyano-2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran

HRID 264819Notes

Reaction equation

HRID 264819 reaction equation
C[Si]([C:5]#[N:6])(C)C.[F:7][CH2:8][C:9]1([CH2:23][F:24])[CH2:14][C:13](=O)[C:12]2[CH:16]=[C:17]([N+:20]([O-:22])=[O:21])[CH:18]=[CH:19][C:11]=2[O:10]1.C1C=CC=CC=1.P(Cl)(Cl)(Cl)=O>[I-].[Zn+2].[I-].CCCCCC.C(Cl)Cl.N1C=CC=CC=1>[F:7][CH2:8][C:9]1([CH2:23][F:24])[CH:14]=[C:13]([C:5]#[N:6])[C:12]2[CH:16]=[C:17]([N+:20]([O-:22])=[O:21])[CH:18]=[CH:19][C:11]=2[O:10]1

Participants

9

Reactant 4

HCID 241BenzeneHCID 24813Phosphorus oxychlorideHCID 82115Trimethylsilyl cyanideHCID 155458532,2-bisfluoromethyl-3,4-dihydro-6-nitro-2H-1-benzopyran-4-one

Product 1

HCID 211949804-cyano-2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran

Reagents, catalysts & solvents 4

HCID 9883512zinc(II)iodideCatalystHCID 1049PyridineSolventHCID 6344DichloromethaneSolventHCID 8058HexaneSolvent

Procedure

2.52 ml of trimethylsilylcyanide and 0.82 g of zinc iodide were added to a mixture of 4.05 g of 2,2-bisfluoromethyl-3,4-dihydro-6-nitro-2H-1-benzopyran-4-one and 10 ml of dried benzene, and the mixture was stirred at room temperature for 12 hours. Further, 8 ml of pyridine and 4.41 ml of phosphorus oxychloride were added thereto, followed by heat-refluxing for 6 hours. Ice water was added to the reaction mixture which was then made acidic with hydrochloric acid, and the mixture was extracted with methylene chloride. After washing the organic layer with water and drying, the residue obtained by concentration under reduced pressure was subjected to silica gel column chromatography (an eluting solvent: methylene chloride:hexane=7:3) to obtain 0.99 g of 2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran-4-carbonitrile having a melting point of 136°-137° C.

Workup

  1. temperatureby heat-refluxing for 6 hours
  2. extractionmade acidic with hydrochloric acid, and the mixture was extracted with methylene chloride
  3. washAfter washing the organic layer with water
  4. customdrying
  5. customthe residue obtained by concentration under reduced pressure

Sources & evidence

ORD record
ord-17d750409f484810851a5b94615258e5
Source dataset
uspto-grants-1997_07
Patent number
US05646310

Reaction notes

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