222 Scientific Proceedings, Royal Duhlin Society. 



mass of tetiyl became quite soft, and formed into lumps, but on continuing the 

 washing it began to harden and break up. B'rom the first wash waters 77 g. of 

 a yellow solid was obtahied on evaporation, m.p. 176-177° C, which, on crystal- 

 lisation from benzene, gave almost colourless crystals, melting at 180-181° C. 

 (uncorr.) with decomposition, and was identified as trinitro methyl nitro amido 

 phenol (oxy-tetryl). A further 23 g. was obtained from the second wash 

 waters, but none from the third. 



The washed tetryl, which was very brown in colour, weighed 53 g., being 

 65-8 per cent, of the theoretical yield. The melting point of the product was 

 125-5°-126-5° C. (corr.). On crj^stallising from aqueous acetone the melting 

 point of the product was 126-127° C. (corr.). 



Experiment 2. — Nitration of Methyl Phenyl Nitrosamine (pure). 



30 g. of the methyl phenyl nitrosamine, b.p. 128-130° C. at 15 mm., was 

 added gradually to 97 per cent, sulphuric acid (300 g.), with cooling and 

 efficient stirring, the temperature being maintained at 0° C. 92 per cent, nitric 

 acid (84 g.) was warmed to 45° C, and the nitrosamine solution slowly added, 

 the temperature being maintained at 50-55° C. by external cooling. It was 

 noticed that the heat of reaction was much lower than had been the case with 

 monomethylaniline — in fact, the easy running of the nitration was a distinct 

 feature of the process. "When about half of the sulphate solution had been 

 added, the reacting mass became slightly turbid, and almost immediately hard 

 crystals of tetryl began to separate. After all the sulphate solution had been 

 added, the mixture was maintained at 50-55° C. for a further period of one hour 

 by external heating. The whole was then allowed to cool to 20° C. and filtered. 

 The acid tetryl was treated exactly as in Experiment 1. From the first wash water 

 on evaporation 02 g. of a yellow, somewhat tarry solid was obtained, which on 

 crystallisation from aqueous acetone melted at 119-121° C, showing it to be 

 probably a crude tetryl. The second and third washings gave no weighable 

 residue. The washed tetryl was cream in colour, and weighed 55 g., being 

 87 per cent, of the theoretical yield. The melting point of the product was 

 128 0-1290° C. (corr.), which on crystallising from aqueous acetone melted at 

 1290-129-5° C. 



Experiment 3. — Nitration of Crude Methyl Phenyl Nitrosamine. 



In view of the good results obtained with pure methyl phenyl nitrosamine, it 

 was considered advisable to examine the behaviour of the crude product, such 

 as would be obtained directly from the commercial grade methylaniline. A 

 synthetic mixture of 79 per cent, methylaniline and 21 per cent, dimethyl- 

 aniline was made up, dissolved in the requisite amount of dilute hydrochloric 

 acid, and treated with just sufficient sodium nitrite solution to form the 

 nitrosamine from the secondary base. The yield of crude nitrosamine was 

 90 per cent, of the theoretical. This product appeared to contain a little 

 p-nitroso compound. The nitration was cax^ried out with the same quantities 

 and under the same conditions as in Experimeiit 2. The reaction proceeded 

 exactly as in the previoiis instance. No weighable residue was obtained from 

 any of the wash waters, and the tetryl, which was cream to straw-yellow in 

 colour, weighed 553 g., being 87-3 per cent, of the theoretical jdeld. The 

 melting point of the product was 127-5-128-5° C. (corr.), which on recrystallisa- 

 tion from aqueous acetone melted at 128-129° C. 



Consequently the crude nitrosamine is a suitable material for the production 

 of tetryl. This indicates the possibility of using the monomethylaniline in the 



