Ammonia → 2,6-Dimethylaniline

Participants

Reaction Steps

A solution of 19.7 g (0.158 mole) of 2,6-dimethyl-cyclohex-2-en-1-one in 180 ml of conc. ammonia is heated, after the addition of 4.0 g of palladium on charcoal (5%), in a hydrogenating autoclave for 4 hours at 280°-290° C., whereby a pressure of 20 bars is established, and is then maintained under these conditions for 5 hours. Cooling and pressure release are then carried out; the contents are again heated for about 5 hours and the pressure is again released. In order to effect the complete removal of hydrogen, the procedure of heating and pressure release is carried out in all three times. An addition is then made of 150 ml of ether and the catalyst is filtered off. The filter residue is washed three times alternately with 100 ml of ether and water, respectively. The mother liquor is extracted, after separation of the ether phase, five times with 150 ml of ether each time. The combined ether phases are dried over magnesium sulphate. After the ether has been distilled off, there remains 17.0 g of crude 2,6-dimethylaniline, from which is obtained, by distillation in a water-jet vacuum, 12.0 g (63% of theory) of pure 2,6-dimethylaniline; b.p. 103° C./ 18 Torr.

Provenance & Evidence