( 74 ) 



mz=|iiO|, b — \{)ï()\ broad iiiid lustrous; o = \i22\ large; r = |102| 

 narrower; q = \012\ small very completely cleavable towards b, 

 fairly so towards a. Optical axial plane is |001|; First diagonal is 

 the ri-axis. Faint dispersion, apparent axial angle in « monobromo- 

 naplitaline about 70°. 



Dr. JxVEGER intends publishing a more detailed examination later on. 



If symmetric nitro-m-xylene is allowed to remain in contact for 

 some time at the ordinary temperature with nitric acid of sp. gr. 1.52, 

 the 4-5-dinitro-product is formed^). If the solution is poured into 

 water a white flocculent precipitate is formed, which when recrys- 

 tallised from alcohol yields fine, colorless needles m.p. '132°. As this 

 substance on subsequent nitration with HNO3 and H^SO^ yields chiefly 

 trinitroxylene m.p. 125° the NO^-group must have been introduced 

 into the position 4, for, if it had been introduced into position 2 

 the subsequent nitration would have formed exclusively trinitroxylene 

 m.p. 90°. 



Clin CII3 CH, 



' ' 132° 1 II0SO4 125° 



NO2 NO, 



All etfort to pre|)arc tetrani(ro-m-xylene from 4-5-(>trinitro-m-xylene 

 ended in failure. The trinitro-xylene was treated at 150^ with HNO^ 

 (sp. gr. 1.52) and HjSO^. The substance was to a large extent 

 destroyed but a small crop of colorless crystals was obtained m. p. 

 lOO''. These crystals were readily soluble in alcohol or warm water; 

 the solutions had a strongly acid reaction so that probably one of 

 the CH3 groups was oxidised to COOH. Tetranitio-m-xylene which 

 ought to have readily yielded trinitro-s.xylidine ') on treatment with 

 alcoholic ammonia was not found. 



As the compound described by Drossbach ') as trinitro-o-xylene 

 has been found by Nölting^) to be an impure triuitro-m-xylene, four 

 of the possible six trinitro-xylenes (0. m. and p.) are now known, 

 namely, the three trinitro-m-xylenes and also trinitro-p-xylene. 



Summary. Symmetric nitro-m-xylene yields on treatment with 

 nitric acid 4-5-dinitro-ni-xylene ; on nitration with HNO3 (sp. gr. 1.52) 

 and H,SO, two isomeric trinitro-m-xylenes are formed being chiefly 

 the 4-5-6-trinitro-l-3-xylene m. p. 125' besides a smaller quantity 

 of 2-5-6-trinitro-l-3-xylene m. p. 90''. 



Amsterdam, May 1905. 



1) A perceptible amount of 2-5-dinitro-m-xylene was not found. 



2) Ber. 28. 2047. Rcc. 21. 329. 



3) Ber. 19. 2519. 



4) Ber. 35. 634. 



