反应详情

温度

-20 °C

A suspension of 2.51 g of methyltriphenylphosphonium bromide in 80 ml of absolute tetrahydrofuran was placed at -20° C. while gassing with argon in a sulphonation flask provided with a dropping funnel and thermometer and treated with 7.6 ml of an about 0.8M solution of butyl lithium in hexane. After stirring at -20° C. for 30 minutes, a solution of 1.0 g of trans-4-(p-cyanophenyl)cyclohexanecarboxaldehyde in 10 ml of absolute tetrahydrofuran was added dropwise at -20° C. within 5 minutes to the yellow mixture, whereby the yellow colour disappeared. The mixture was now stirred at -20° C. for a further 30 minutes and then poured into 100 ml of water and extracted three times with 100 ml of diethyl ether each time. The organic phases were washed twice with 100 ml of water each time, dried over magnesium sulphate and concentrated. Low-pressure chromatography (0.5 bar) of the residue (2.3 g) on silica gel with ethyl acetate/petroleum ether (vol. 3:97) gave 897 mg (91%) of p-(trans-4-vinylcyclohexyl)benzonitrile as colourless crystals; purity 99.4%. By additional crystallization from 22 ml of methanol there was obtained p-(trans-4-vinylcyclohexyl)benzonitrile in a purity of 99.95%; m.p. (C--I) 56.4° C., cl.p. 28.5° C.

1. customwas placed at -20° C.
2. customwhile gassing with argon in a sulphonation flask
3. customprovided with a dropping funnel
4. stirringThe mixture was now stirred at -20° C. for a further 30 minutes
5. extractionextracted three times with 100 ml of diethyl ether each time
6. washThe organic phases were washed twice with 100 ml of water each time
7. dry with materialdried over magnesium sulphate
8. concentrationconcentrated