146 REPORTS ON THE STATE OF SCIENCE. 
115° and 71° were obtained. The methyl groups in the hydrocarbons 
are both attached to the same carbon atom, and in such cases it has been 
frequently observed! that the transformation into an aromatic substance 
C(CH;), C(CH;). C(CH;), 
HC CH H,C CH, H.C ‘CH 
< = 
HC CH B,HC CHB, HC CH 
CH, CH, CH 
results in one of the methyl groups wandering into an ortho position, 
but never into a meta or para position. It was therefore presumed that 
the above-mentioned substances melting at 115° and 71° were trinitro- 
o-xylenes. 
No trinitro-o-xylenes had, up to that time, been described, and 
experiments were therefore undertaken with the object of preparing 
these substances. The work has now been completed,? and has shown 
that the above-mentioned derivatives, melting at 115° and 71°, are the 
two possible trinitro-o-xylenes. In the course of the work all the 
mono-, di-, and trinitro-o-xylenes were isolated and described. 
2. Hydro-aromatic Kelones. Part 1.—Synthesis of trimethylcyclo- 
hexenone (Isophorone) and some homologues.” 
Chlorodimethylcyclohexenone contains a reactive chlorine atom, 
easily replaceable by an ethoxy group under the influence of sodium 
ethoxide, giving rise to the ethyl ester of dimethyldihydroresorcin. 
Condensation takes place readily between chlorodimethyleyclo- 
hexenone and ethyl sodiomalonate. The product is not, as might have 
been expected, the substance having formula I., but consists of ethyl 
(CHY.CCot DCH 
| CH,— CO 
(L)  CH(CO,C,H,), + C,H,OH = (CH,),CKGy" gg >CH 
| 
(Il.)  CH,. C0,C,H, + CO(0C,H,), 
dimethyleyclohexenoneacetate II, whose formation necessitates the 
elimination of a carbethoxy group, and this has been proved to take 
place with formation of ethyl carbonate. The product of hydrolysis 
of this ethyl ester is trimethylcyclohexenone III, identical with 
isophorone. 
(CHL CH _o PCH +H,0 =(CH,),C <qlp 28 +00, +C,H,OH 
| 
CH, .CO,C,H, (IL) CH, 
As, however, it gives only one oxime melting at 78°, whereas the 
isophorone prepared from acetone gives two oximes, melting at 75° and 
1 J.0.8., 1904, 85, 264 ; 1906, 89, 875. i 
2 Tbid., 1909, 95, 202. 8 Crossley and Gilling, J.€.S., 1909, 95, 19. 
4 Proc. C. 8., 1909, 25, 96. 
