反应详情

温度

-50 °C

27 ml (48 mmol) of a 1.8 M solution of phenyllithium in cyclohexane/diethyl ether (7:3) are added dropwise at −65° C. to a solution/suspension of 45 mmol of methoxymethyltriphenylphosphonium chloride in 280 ml of dry diethyl ether. The mixture is stirred at the same temperature for 30 minutes, then kept at −10° C. for 30 minutes and subsequently re-cooled to −50° C. 16 mmol of 3,4,5-trifluoro-4′-(4-propylcyclohexyl)biphenyl -2-carbaldehyde are added at this temperature. The reaction mixture is allowed to thaw slowly, and stirring is continued at room temperature. Ice-water is added to the reaction mixture, and the organic phase is separated off and washed with cold water. After drying using sodium sulfate, the mixture is evaporated under reduced pressure, and the residue is stirred with n-heptane and filtered. The filtrate is chromatographed on silica gel (n-heptane/ethyl acetate 98:2), giving 3,4,5-trifluoro-2-(2-methoxyvinyl)-4′-(4-propylcyclohexyl)biphenyl (mixture of Z and E isomers).

1. waitkept at −10° C. for 30 minutes
2. stirringstirring
3. customis continued at room temperature
4. customthe organic phase is separated off
5. washwashed with cold water
6. customAfter drying
7. customthe mixture is evaporated under reduced pressure
8. stirringthe residue is stirred with n-heptane
9. filtrationfiltered
10. customThe filtrate is chromatographed on silica gel (n-heptane/ethyl acetate 98:2)