2 января, 2016 
Pokraskin 50 cc. of the aniline solution is measured out and mixed with 50 cc. concentrated hydrochloric acid. The mixture is cooled by placing the measuring flask in ice water, and 50 cc. 1 N nitrite solution is added while the mixture is swirled to provide agitation. The solution is kept in ice water for 20 minutes after which it should show only the slightest reaction for nitrous acid. Ice water is added to make the volume up to 500 cc. and the solution is ready for use. Under no circumstances must the diazotization be carried out in less than 20 minutes, since the reaction takes this long under the conditions employed. The diazo solution can
be held unchanged for about 4 hours at 0°C. in the dark, and must always be freshly prepared.
Опубликовано в рубрике 