S([O-])([O-])(=O)=O.[Na+].[Na+].[C:8]1([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[CH:13]=[CH:12][C:11]([CH:14]=O)=[CH:10][CH:9]=1.S([O-])([O-])(=O)=O.O[NH3+:28].O[NH3+]>O>[C:8]1([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)[CH:13]=[CH:12][C:11]([C:14]#[N:28])=[CH:10][CH:9]=1With stirring (20 rpm), a turbine dryer is charged at room temperature with 1007 parts by weight of anhydrous sodium sulfate, 222 parts by weight of biphenyl-4-carbaldehyde and 105 parts by weight of hydroxylammonium sulfate. Following evacuation to 13 mbar, the mixture is heated to 70° C. and stirred at this temperature for 3 hours. It is subsequently heated at 130° C., during which about 43 parts by weight of water are removed by distillation. After half an hour, the pressure is reduced to 4 mbar and the jacket temperature is raised successively to 170° C. over the course of 60-70 minutes, the product undergoing fractional distillation. 194 parts by weight of biphenyl-4-carbonitrile are obtained with an outstanding purity of ~98-99% (HPLC) and a melting point of 83°-85° C., along with 10 parts by weight of a less pure fraction.
Loading…
