104 REPORTS ON THE STATE OF SCIENCE. 
The Study of Hydro-aromatic Substances.—Report of the Committee, 
consisting of Dr. K. Divers (Chairman), Professor A. W. CROSSLEY 
(Secretary), Professor W. H. Perkin, Dr. M. O. Forster, and 
Dr. H. R. Le Sueur. 
1. The Action of Reducing Agents on 5-chloro-3-keto-1 : 1-dimethyl- 
A‘-tetrahydrobenzene.'\—Some little time since? it was shown that the 
principal product obtained by the action of sodium in moist ethereal 
solution on chloroketodimethyltetrahydrobenzene (I.) was 3-hydroxy- 
1 : 1-dimethylhexahydrobenzene (II.), which may be described as the 
CH,—CO CH, . CH(OH) 
CMe "_Scw CMe, Dou 
CH, . Coir NCH, 
(1.) 
(IL) 
limit-reduction product of the chloroketone. A further study of the 
reaction has proved that the addition of a small quantity of alcohol to the 
ether has a beneficial effect, considerably increasing the yield of hydroxy- 
dimethylhexahydrobenzene, and rendering it much easier to remove the 
chlorine completely from the chloroketone. As alcohol had such a decided 
influence it was thought advisable to try the reduction with sodium in 
absolute alcoholic solution. The reaction proceeded, however, in an 
unexpected direction, and demonstrated the fact that the chlorine atom in 
chloroketodimethyltetrahydrobenzene is very reactive, a fact which greatly 
enhances the possibilities of the use of this and similar chloroketones for 
synthetical purposes. Small quantities of hydroxydimethylhexahydro- 
benzene (II.), but principally 3-hydroxy-5-ethoxy-1 : 1-dimethylhexa- 
hydrobenzene (1V.), were obtained, and it is evident that the sodium 
CH,—co OH, . CH(OH) 
CMex 20 on CMe, Son 
hee Gun’ eye ons CHLORHY 
‘Nai OEt 
any (IV.) 
ethoxide formed in the first stages of the reduction reacts with the 
chlorine atom of the chloroketone to give the substance represented by 
formula III., which is then further reduced to the corresponding 
saturated compound. The constitution of the latter is proved by analysis 
and by the facts that a Zeisel determination shows it to contain an ethoxy- 
group, and that, when treated with acetyl- or benzoyl-chlorides, it yields 
acetyl- or benzoyl-derivatives UE dec 
The main object of the investigation was, however, to find reducing 
agents, less powerful than sodium in moist ethereal solution, which would 
be discriminating in their action ; so that it might be possible to prepare 
from chloroketodimethyltetrahydrobenzene, first, a ketodimethyltetra- 
hydrobenzene, differing from the former only in that chlorine would be 
replaced by hydrogen, and, secondly, the corresponding ketodimethyl- 
hexahydrobenzene. Complete success has attended the experiments, and 
further work is in progress with the object of proving that the reactions 
are general ones. 
' Crossley and Renouf, J.C.S., 1907, 91, 63. 
2 Thid., 1905, 87, 1487. 
