Thionyl Chloride → HCID 20070996, compound

HRID 981801Notes

Reaction equation

HRID 981801 reaction equation
S(Cl)(Cl)=O.[Br:5][C:6]1[CH:16]=[CH:15][C:9]([CH2:10][CH2:11][C:12]([OH:14])=O)=[CH:8][CH:7]=1>>[Br:5][C:6]1[CH:7]=[CH:8][C:9]2[CH2:10][CH2:11][C:12](=[O:14])[CH2:8][C:9]([CH3:15])([CH3:10])[C:15]=2[CH:16]=1

Participants

3

Reactant 2

HCID 24386Thionyl ChlorideHCID 27356093-(4-Bromophenyl)propionic acid

Product 1

HCID 20070996HCID 20070996, compound

Procedure

19.0 ml of thionyl chloride are added to 30 g of p-bromohydrocinnamic acid and heated to reflux for 30 minutes. After cooling, the excess reagent is removed by evaporation (finally at 0.5 Torr) and the crude acid chloride is dissolved in 300 ml of carbon disulfide. After cooling to -10°, 3.5 ml of tin tetrachloride are added under an argon atmosphere. Thereafter, 25 ml of isobutylene are introduced and the reaction mixture is warmed slowly to room temperature. After renewed cooling to 0°, 35 g of aluminum trichloride are added. The reaction mixture is stirred overnight, poured on to ice, extracted with diethyl ether and the extract is washed with water and phosphate buffer (pH 7) and dried. After evaporation, the residue is chromatographed on silica gel with petroleum ether (low-boiling) and ethyl acetate (9:1). There is obtained 2-bromo-5,6,8,9-tetrahydro-9,9-dimethyl-7-benzocycloheptenone in the form of yellowish crystals of m.p. 67°-68° (from hexane).

Workup

  1. temperatureheated
  2. temperatureto reflux for 30 minutes
  3. temperatureAfter cooling
  4. customthe excess reagent is removed by evaporation (finally at 0.5 Torr) and the crude acid chloride
  5. dissolutionis dissolved in 300 ml of carbon disulfide
  6. temperatureAfter cooling to -10°
  7. addition3.5 ml of tin tetrachloride are added under an argon atmosphere
  8. additionThereafter, 25 ml of isobutylene are introduced
  9. temperatureAfter renewed cooling to 0°
  10. addition35 g of aluminum trichloride are added
  11. additionpoured on to ice
  12. extractionextracted with diethyl ether
  13. washthe extract is washed with water and phosphate buffer (pH 7)
  14. customdried
  15. customAfter evaporation
  16. customthe residue is chromatographed on silica gel with petroleum ether (low-boiling) and ethyl acetate (9:1)

Sources & evidence

ORD record
ord-7fda8d88ac774fc08fdd2959e5b436a8
Source dataset
uspto-grants-1991_02
Patent number
US04992574

Reaction notes

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