Hydrochloric Acid → 4-Hydroxy-4'-chlorobenzophenone

HRID 225118

Reaction equation

HRID 225118 reaction equation
[Cl-].[Al+3].[Cl-].[Cl-].[C:5]1([O:11]C)[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1.[Cl:13][C:14]1[CH:22]=[CH:21][C:17]([C:18](Cl)=[O:19])=[CH:16][CH:15]=1.Cl>C(Cl)Cl>[Cl:13][C:14]1[CH:22]=[CH:21][C:17]([C:18](=[O:19])[C:8]2[CH:7]=[CH:6][C:5]([OH:11])=[CH:10][CH:9]=2)=[CH:16][CH:15]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 7519AnisoleHCID 85014-Chlorobenzoyl chlorideHCID 6451240Aluminum(III) Chloride

Product 1

HCID 1235044-Hydroxy-4'-chlorobenzophenone

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
25 °C

Procedure

510 g of aluminium chloride (3.82 M), then 3.5 l of dry methylene chloride, and, slowly, 430 g (4 M) of anisole are added to a 5-liter flask; the flask is cooled to maintain the temperature at about 25° C., and 600 g (3.44 M) of 4-chlorobenzoyl chloride is then added dropwise; the reaction mixture is next heated 6 hours under reflux, is left to cool to about 25° C., and the reaction mixture is poured onto 5 kg of ice and 0.5 l of concentrated HCl; the mixture is stirred well during this hydrolysis; the methylene chloride phase is decanted, washed once with water, and transferred to another 5-liter vessel. The methylene chloride is removed by evaporation and replaced in the flask by 2 l of chlorobenzene; a Dean-Stark apparatus is connected and the reaction mixture is refluxed to dehydrate the medium; when this operation is complete the mixture is cooled to approximately 50° C. and 800 g (6 M) of aluminium chloride is added; the reaction mixture is heated 1 hour 30 minutes under reflux (very gentle reflux), and demethylation proceeds rapidly; the reaction mixture is cooled and poured onto 6 kg of ice and 0.5 l of concentrated HCl; the mixture is stirred for 1 hour 30 minutes and the precipitate is dried; the latter is washed with water, with methylene chloride, and then dried:

Workup

  1. temperaturethe flask is cooled
  2. temperaturethe reaction mixture is next heated 6 hours
  3. temperatureunder reflux
  4. waitis left
  5. temperatureto cool to about 25° C.
  6. customthe methylene chloride phase is decanted
  7. washwashed once with water
  8. customtransferred to another 5-liter vessel
  9. customThe methylene chloride is removed by evaporation
  10. temperaturethe reaction mixture is refluxed
  11. temperatureis cooled to approximately 50° C.
  12. addition800 g (6 M) of aluminium chloride is added
  13. temperaturethe reaction mixture is heated 1 hour 30 minutes
  14. temperatureunder reflux (
  15. temperaturevery gentle reflux), and demethylation proceeds rapidly
  16. temperaturethe reaction mixture is cooled
  17. additionpoured onto 6 kg of ice and 0.5 l of concentrated HCl
  18. stirringthe mixture is stirred for 1 hour 30 minutes
  19. customthe precipitate is dried
  20. washthe latter is washed with water, with methylene chloride
  21. customdried

Sources & evidence

ORD record
ord-5dd2b099dc234fd39c8c8d14a7856e43
Source dataset
uspto-grants-1980_11
Patent number
US04235896

Linked notes

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