NOTES ON SCIENTIFIC RESEARCH. 77 
Hydrocarbons. | 
Hydrocarbons from hydroaromatic alcohols and ketones. 
K. von Auwers, together with W. Treppmann and F. Krollpfeiffer*), investigated 
some unsaturated hydroaromatic hydrocarbons and ketones. Dehydration of 1-phenyl- 
cyclohexanol yielded phenyleyclohexene, CiezHi4, on which Friedmann and Bauer’) have 
reported already. From 1-benzylcyclohexanol-1 or phenylcyclohexylcarbinol, 1-benzyl- 
cyclohexene-1, Ci3His, forms by dehydration. The nitrosochloride of the benzylcyclo- 
hexene can be converted into the oxime of the 1-benzylcyclohexene-5-one-2, from 
which, on hydrolysis with 30 p.c. sulphuric acid, 1-benzylcyclohexen-5-one-2, CisHi,O 
resulted. .By reduction with hydrogen and colloidal palladium it yields 1-benzyl- 
eyclohexanone-2, Ci3HisO. The action of magnesium-phenylbromide on 1,3-dimethyl- 
cyclohexen-3-one-5 leads to 1,3-dimethyl-5-phenylcyclohexanol-5, which passes into 
1,3- dimethyl -5-phenylcyclohexadiene-3,5, CisHie by dehydration. When boiled with 
sodium and alcohol, this hydrocarbon yields 1,3-dimethyl-5-phenylcyclohexene-3, Cis His. 
1-Methyl-3-oxymethylenecyclohexanone-2, CsHi4Oz, results through the action of sodium 
and amyl formate on methylcyclohexanone. The reduction with palladium and hydrogen 
leads to 1,3-dimethylcyclohexanone-2, CigHisO, from which, by treatment with methyl 
iodide and magnesium, 1,2,3-trimethylcyclohexene-1, CyHis, forms, an easily mobile 
liquid of agreeable, mild odour; b. p. 149.6 to 150° (749 mm.). 
Mercuric acetate in the investigation of essential oils. 
In order to investigate the terpenic portion of volatile oils, L. Balbiano*) recommends 
to use an aqueous solution of mercuric acetate. This reacts, as it is known, with 
pinene in the heat, forming dihydroxypinene, whereas with camphene it gives a quan- 
titative yield of an unsoluble compound melting at 187°, from which the camphene 
can be recovered by heating with zinc and dilute hydrochloric acid*). Mercuric acetate 
does not react with either aromatic hydrocarbons, such as cymene, or bicyclic hydro- 
carbons (CioHis) of the pinane type. 
Already as far back as 1903°), we pointed out that this reaction may be used to 
advantage in the investigation of volatile oils. We then succeeded, with the aid of 
the mercuric acetate compound, in isolating camphene from the fractions of Ceylon 
citronella oil that boil between 158 and 162°, and to characterize it by transforming 
it into isoborneol. 
The therapeutical use of pinene ozonide has been discussed on p.71 of this Report. 
As to the content of 8-pinene in Spanish oil of turpentine, see p. 40. 
Phellandrene. So far, solid, well defined hydrogen haloids had not been prepared 
from §-phellandrene. L.Francesconi and E. Sernagiotto®) have now treated $-phellan- 
drene, obtained from bupleurum oil, with alcoholic hydrochloric acid, when, in addition 
to an oily product, terpinene dihydrochloride resulted (m.p. 51 to 52°). 
Azulene. On page 87 of our previous Report, we discussed a paper by A. E. Sherndal 
on this interesting, intensely blue hydrocarbon, to which some essential oils owe their 
colour. The author has meanwhile continued his investigations and has arrived at 
1) Berl. Berichte 48 (1915), 1207, 1226. — *) Annal. de Chim. IX. 1 (1914), 384. — 3) Berl. Berichte 48 
(1915), 394. — *) Comp. Reports April 1903, 85; April 1904, 100; October 1906, 101; April 1911, 118; April 
1915, 44. — *) Report April 1903, 86. — %) Gazz. chim. ital. 44 (1914), Il. 456; Chem. Zentralbl. 1915, I. 892. 
