Acetyl chloride → 3-(2',4'-Difluoro-4-biphenylyl)-3-hydroxybutyric acid ethyl ester

HRID 26899

Reaction equation

HRID 26899 reaction equation
[C:1]([C:4]1[CH:9]=[CH:8][C:7]([C:10]2[CH:15]=[CH:14][C:13]([F:16])=[CH:12][C:11]=2[F:17])=[CH:6][CH:5]=1)(=[O:3])[CH3:2].FC1C=C(F)C=CC=1C1C=CC=CC=1.C(Cl)(=O)C.[Al+3].[Cl-].[Cl-].[Cl-].Br[CH2:41][C:42]([O:44][CH2:45][CH3:46])=[O:43]>C1(C)C=CC=CC=1.C1C=CC=CC=1>[CH2:45]([O:44][C:42](=[O:43])[CH2:41][C:1]([C:4]1[CH:9]=[CH:8][C:7]([C:10]2[CH:15]=[CH:14][C:13]([F:16])=[CH:12][C:11]=2[F:17])=[CH:6][CH:5]=1)([OH:3])[CH3:2])[CH3:46]

Participants

8

Reactant 5

HCID 6367Acetyl chlorideHCID 7748Ethyl bromoacetateHCID 1045421-(2',4'-Difluoro(1,1'-biphenyl)-4-yl)ethan-1-oneHCID 1699742,4-Difluoro-1,1'-biphenylHCID 6451240Aluminum(III) Chloride

Product 1

HCID 538342513-(2',4'-Difluoro-4-biphenylyl)-3-hydroxybutyric acid ethyl ester

Reagents, catalysts & solvents 2

HCID 241BenzeneSolventHCID 1140TolueneSolvent

Procedure

23.2 g. of 4-acetyl-2',4'-difluorobiphenyl, obtainable by reacting 2,4-difluorobiphenyl with acetyl chloride in the presence of AlCl3, and 11.1 ml. of ethyl bromoacetate are dissolved in a mixture of 75 ml. of benzene and 75 ml. of toluene. A 40 ml. portion of the resulting solution is added to 7 g. of zinc powder, previously washed successively with 1% hydrochloric acid, water and acetone and dried and the mixture is warmed to 70° with stirring and under a nitrogen atmosphere. After the reaction has begun, the remainder of the solution is added dropwise, the mixture is heated under reflux for one hour and cooled and 40 ml. of 20% sulfuric acid are added drop-wise in order to decompose the alcoholate Z--C(CH3) (OZnBr)--CH2 --COOC2H5 (Z is 2',4'-difluoro-4-biphenylyl). The organic phase is separated off and worked up in the customary manner to give 3-(2',4'-difluoro-4-biphenylyl)-3-hydroxybutyric acid ethyl ester, m.p. 96°-97° C.

Workup

  1. additionportion of the resulting solution is added to 7 g
  2. washof zinc powder, previously washed successively with 1% hydrochloric acid, water and acetone
  3. customdried
  4. temperaturethe mixture is warmed to 70°
  5. additionthe remainder of the solution is added dropwise
  6. temperaturethe mixture is heated
  7. temperatureunder reflux for one hour
  8. temperaturecooled
  9. additionof 20% sulfuric acid are added drop-wise in order
  10. customThe organic phase is separated off

Sources & evidence

ORD record
ord-e10f69b05c2e4c25830c03c54053918b
Source dataset
uspto-grants-1979_04
Patent number
US04151302

Linked notes

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