372 PBOCEEDINGS OP THE AMERICAN ACADEMY 



XIX. 



CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 



HARVARD COLLEGE. 



ON TPIE ACTION OF NITRIC ACID ON SYMMETRICAL 



TRICHLORBENZOL. 



By C. Loring Jackson and John F. Wing. 



Presented March 9, 1887. 



We were led to take up the study of this subject by our work upon 

 the constitution of benzoltrisulphonic acid, described in the preceding 

 paper, since the trichlorbenzol derived from that substance by re- 

 placing its sulpho groups with chlorine, although melting at 63° like 

 the symmetrical compound (melting point 63°.5 according to Beilstein 

 and Kurbatow*), gave on treatment with nitric acid a body melting at 

 130°, whereas Beilstein and Kurbatow obtained in this way trichlor- 

 mononitrobenzol,t melting point 68°. To find the cause of this dis- 

 crepancy we have prepared the symmetrical trichlorbenzol, and treated 

 it with nitric acid in the cold, when we found that the product was 

 the substance melting at 130° (or more accurately at 129°. 5) mentioned 

 above, which proved on analysis to be trichlordinitrobenzol. This 

 result was the more strange, because our nitric acid had a specific 

 gravity of only 1.505, whereas that used by Beilstein and Kurbatow 

 showed 1.52, and in order to get their trichlormononitrobenzol we 

 found it necessary to dilute our acid to 1.46. Since these experi- 

 ments seemed to sliow that our nitric acid was more efficient in its 

 action than that used by Beilstein and Kurbatow, we determined to 

 study the subject more carefully, and next attempted the preparation 

 of the trichlortrinitrobenzol, which we obtained without difficulty by 

 boiling the trichlordinitrobenzol for about two hours with a mixture 

 of our nitric acid and fuming sulphuric acid. Both this substance 



* Ann. Chem., cxcii. 233. t Ber. d. ch. G., 1877, p. 271. 



