Hydrochloric Acid → 8-fluoro-3-(4-fluorophenyl)-2,3-dihydro-4H-1-benzothiopyran-4-one

HRID 1646987Notes

Reaction equation

HRID 1646987 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([CH:8]([CH2:12][S:13][C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][C:15]=2[F:20])[C:9]([OH:11])=O)=[CH:4][CH:3]=1.[Cl-].[Cl-].[Cl-].[Al+3].Cl>S(Cl)(Cl)=O>[F:20][C:15]1[C:14]2[S:13][CH2:12][CH:8]([C:5]3[CH:4]=[CH:3][C:2]([F:1])=[CH:7][CH:6]=3)[C:9](=[O:11])[C:19]=2[CH:18]=[CH:17][CH:16]=1

Participants

5

Conditions

Temperature
0 °C

Procedure

The acid from Step C (4.5 g, 15 mmole) was dissolved in 30 ml of thionyl chloride and refluxed for four hours. After cooling the thionyl chloride was concentrated and the residue taken up in carbon tetrachloride. The carbon tetrachloride was concentrated and the residue was taken up in 30 ml of dichloroethane. To the dichloroethane solution being cooled in an ice bath, was added aluminum trichloride (total of 2.1 g, 16 mmole) in three portions every 15 min. After stirring the black solution for an additional 30 min at 0° C., a 5% aqueous HCl solution was added. The aqueous phase was separated and extracted twice with methylene chloride. The organic phases were combined, dried (MgSO4), and concentrated to give the crude product as a yellow oil (3.4 g, 82% yield).

Workup

  1. temperaturerefluxed for four hours
  2. concentrationwas concentrated
  3. concentrationThe carbon tetrachloride was concentrated
  4. temperatureTo the dichloroethane solution being cooled in an ice bath
  5. customThe aqueous phase was separated
  6. extractionextracted twice with methylene chloride
  7. dry with materialdried (MgSO4)
  8. concentrationconcentrated

Sources & evidence

ORD record
ord-0a4260efac9d41d8ad0b12ffbc8a1e52
Source dataset
uspto-grants-1993_01
Patent number
US05182303

Reaction notes

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