Bromotrifluoromethane → 3',4'-Dimethyl-2,2,2-trifluoroacetophenone

HRID 1763068Notes

Reaction equation

HRID 1763068 reaction equation
[F:1][C:2](Br)([F:4])[F:3].[CH3:6][C:7]1[CH:8]=[C:9]([CH:13]=[CH:14][C:15]=1[CH3:16])[C:10](Cl)=[O:11].CCCCCC>C(Cl)Cl>[CH3:6][C:7]1[CH:8]=[C:9]([C:10](=[O:11])[C:2]([F:4])([F:3])[F:1])[CH:13]=[CH:14][C:15]=1[CH3:16]

Participants

5

Reactant 3

HCID 6384BromotrifluoromethaneHCID 8058HexaneHCID 27585353,4-Dimethylbenzoyl chloride

Product 1

HCID 27586663',4'-Dimethyl-2,2,2-trifluoroacetophenoneYield 41.2%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

Under protective gas, 41 g (0.27 mol) of trifluoromethyl bromide are condensed into a solution of 42 g (0.25 mol) of 3,4-dimethylbenzoyl chloride in 150 ml of CH2Cl2 in a round-bottomed flask at about -70° C. A solution of 66.7 g (0.27 mol) of phosphorous acid trisdiethylamide in 50 ml of CH2Cl2 are then metered in at about -70° C., the first 90% of the solution being added rapidly and the last 10% of the solution being metered in slowly (during the course of about 2 hours). The mixture is subsequently stirred for one hour more at this temperature and then warmed to room temperature. After addition of the same volume of hexane, 2 phases are formed. After phase separation, the lower phase is carefully extracted using hexane; the combined hexane phases are concentrated and distilled under reduced pressure. 20.8 g (41% yield) of 1-(3,4-dimethylphenyl)- 2,2,2-trifluoroethan-1-one of b.p. 98°-99° C./22 mbar are obtained.

Workup

  1. customare then metered in at about -70° C.
  2. customduring the course of about 2 hours
  3. customare formed
  4. customAfter phase separation
  5. extractionthe lower phase is carefully extracted
  6. concentrationthe combined hexane phases are concentrated
  7. distillationdistilled under reduced pressure

Sources & evidence

ORD record
ord-12f5c3ec032b470c9fb551c1e57fc71b
Source dataset
uspto-grants-1989_05
Patent number
US04835318

Reaction notes

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