154 REPORT—1905. 
the various steps involved being adequately indicated by the following 
formule :— 
C(CH,). C(CHs), C(CH;). 
H,c /~ cH, Hc /~\ cH, H,c / \ CH, 
her tee lly 
HO.C co cic co H.C CHOH 
\Z /, \7 
CH CH CH, 
(CH, ), C(CH,), 
H,c /~ cn, HG 7. “BEE 
Pe al | 
HC CHBr HC CH, 
4 nA 
CH, CH, 
It has not so far been found possible to prove whether the synthetical 
1 ; 1-dimethylhexahydrobenzene is identical with Zelinsky’s hydrocarbon, 
though preliminary experiments would point to their non-identity. 
Certainly neither laurolene nor isolaurolene is identical with 1 : 1-dimethyl- 
A3-tetrahydrobenzene, which has also been recently prepared.! 
Chloromethylhexahydrobenzene.” 
Brunel * has shown that tetrahydrobenzene may be prepared directly 
from hydroxyhexahydrobenzene by the action of dehydrating agents, e.g., 
phosphoric oxide, zinc chloride, or potassium hydrogen sulphate. In the 
latter case the yield amounts to 82 to 83 per cent. of the theoretical, the 
loss being due to the formation of condensation products. When tetra- 
hydrobenzene‘ is acted on with mercuric oxide, iodine, and acetic anhy- 
dride, or with mercuric acetate and iodine, iodocyclohexy] acetate is obtained 
as a yellow oil with aromatic odour. Iodocyclohexyl propionate is also 
described. 
On carefully heating the xanthogenic ether of 1-hydroxy-2-methyl- 
hexahydrobenzene * a hydrocarbon is obtained which, as it gives @-methyl- 
adipic acid on oxidation, must be 1-methyl-A*-tetrahydrobenzene. 
Methyltetrahydrobenzene.° (Compare p. 155.) 
The preparation and properties of A'**-dihydrobenzene, briefly alluded 
to in the last report,’ have been described in detail.® 
Hydrogenation.—Sabatier and Senderens® have published a general 
survey of their work on the reduction of various classes of organic 
substances by means of hydrogen in presence of finely divided metals. 
The first portion of the paper contains a description of the apparatus 
employed, choice of temperature, length of activity of the catalyst, &e. 
Then follows a description of the various substances which have been 
prepared. The great importance of choice of temperature in this reaction 
is well illustrated by the case of phenol. At 140° to 160° pure hydroxy- 
hexahydrobenzene is obtained ; at 215° to 230° a mixture of hydroxy- 
1 Crossley and Renouf, Proc. C. S., 1905, 21, 209. 
? Sabatier and Mailhe, Compt. Rend., 1905, 140, 840. 
$ Bull. Soc., 1905 (3), 38, 270. 
‘ Brunel, Compt. Rend., 1904, 189, 1029. 
5 Markownikoff and Stadnikoff, Annalen, 1904, 386, 310. 
® Sabatier and Mailhe, Compt. Rend., 1905, 140, 350. 
7 Reports, 1904, p. 65. 5 Crossley, J. C. S., 1904, 85, 1403. 
® Ann. Chim. Phys., 1905 (8). 4, 319. 
