Acetyl chloride → 3-(2',4'-Difluoro-4-biphenylyl)-3-hydroxybutyric acid ethyl ester
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
Reactant 5
Product 1
Reagents, catalysts & solvents 2
Procedure
23.2 g. of 4-acetyl-2',4'-difluorobiphenyl, obtainable by reacting 2,4-difluorobiphenyl with actyl 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 actone 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 dropwise 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
- additionportion of the resulting solution is added to 7 g
- washof zinc powder, previously washed successively with 1% hydrochloric acid, water and actone
- customdried
- temperaturethe mixture is warmed to 70°
- additionthe remainder of the solution is added dropwise
- temperaturethe mixture is heated
- temperatureunder reflux for one hour
- temperaturecooled
- additionof 20% sulfuric acid are added dropwise in order
- customThe organic phase is separated off
Sources & evidence
- ORD record
- ord-c985c20feb2c4e9c9187879b5b48680b
- Source dataset
- uspto-grants-1977_11
- Patent number
- US04057647
Reaction notes
Loading…