Potassium Cyanide → 4-Cyanoacetyl-2',4'-difluorobiphenyl

Beteiligte Stoffe

Reaktionsschritte

Grignard reagent obtained from 14.2 g. of methyl iodide and 2.4 g. of magnesium in 100 ml. of THF is added dropwise to a solution of 30.4 g. of 3-(2',4'-difluoro-4-biphenylyl)-3-oxopropionic acid ethyl ester, obtained by brominating 4-acetyl-2',4'-difluorobiphenyl to 4-bromoacetyl-2',4'-difluorobiphenyl, reacting this with KCN to give 4-cyanoacetyl-2',4'-difluorobiphenyl, hydrolyzing the latter and esterifying the reaction product, in 200 ml. of THF. When the addition is complete, the mixture is heated and stirred for 2 hours more on a water bath and cooled. The resulting alcoholate is hydrolyzed with ice and saturated NH4Cl solution. The ether phase is dried and evaporated to give 3-(2',4'-difluoro-4-biphenylyl)-3-hydroxybutyric acid ethyl ester, m.p. 96°-97°.

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