反应详情

In a 500-ml flask, equipped as described in Example 4(a), was placed 250 ml of anhydrous THF and 7.00 ml of diisopropylamine (via syringe). The flask was cooled in a dry ice bath and, with stirring, 21.0 ml of 2.4 molar n-butyllithium in hexane was added via a syringe. The mixture was stirred for 1 hour and then 3.42 g of freshly distilled isobutyronitrile in 20 ml of THF was added in 20 minutes. After an additional hour of stirring, 8.50 g of 4,4'-bis(bromomethyl)biphenyl was added all at once. Stirring at -76° was continued for several hours and overnight as the cooling bath warmed to room temperature. After an additional day of stirring, the solvent was distilled on the water pump. The resulting semisolid residue was dissolved in 500 ml of chloroform and the chloroform solution was extracted 4 times with water (with HCl acidification during the first extraction). Drying the solution over anhydrous magnesium sulfate, filtering, and removal of the solvent in vacuo gave 6.8 g of crude 4,4'-bis(2-methyl-2-cyanopropyl)biphenyl melting at 174° to 182°. After several recrystallizations from acetone, the product melted at 189.3° to 190.8°.

1. customIn a 500-ml flask, equipped
2. temperatureThe flask was cooled in a dry ice bath
3. stirringThe mixture was stirred for 1 hour
4. stirringAfter an additional hour of stirring
5. stirringStirring at -76°
6. stirringAfter an additional day of stirring
7. distillationthe solvent was distilled on the water pump
8. dissolutionThe resulting semisolid residue was dissolved in 500 ml of chloroform
9. extractionthe chloroform solution was extracted 4 times with water (with HCl acidification
10. extractionduring the first extraction)
11. dry with materialDrying the solution over anhydrous magnesium sulfate
12. filtrationfiltering
13. customremoval of the solvent in vacuo