NOTES ON SCIENTIFIC RESEARCH. 135 
This body, when treated with sodium acetate in glacial acetic acid solution and 
subsequent saponification, affords, according to the original material, either d- or 
l-rhodinol. In addition to this, the reaction results in 3,7-dimethyl-octanediol, the 
citronellol-hydrate or -glycol of Tiemann and Schmidt*). When citronellol is taken as 
the starting-point, it is possible to arrive at rhodinol by converting citronellal oxime 
into citronellic acid from primarily-produced citronellic acid nitrile, and converting the 
citronellic acid into the chloride of hydrochloride of rhodinic acid by means of thionyl 
chloride in benzene solution at water-bath temperature. By boiling the ester of this acid 
(b. p. 137 to 140°, 15 mm.) with sodium acetate, as described above, rhodinic ester is 
obtained. This body is reduced to the corresponding alcohol, rhodinol, with sodium 
and absolute alcohol, according to the method of Bouveault and Blanc. The easiest 
way of converting citronellol into rhodinol is by means of the glycol already referred 
to. This glycol also results from the reduction of hydroxycitronellic ester, a liquid 
which boils between 139 and 142° (13 mm.), and which is formed in fairly considerable 
quantities as a by-product in the esterification of citronellic acid with absolute alcohol 
and concentrated sulphuric acid. Less simple is the preparation of the glycol by pro- 
longed shaking of citronellol with 30 p.c. sulphuric acid. When boiled with 5 p.c. 
sulphuric acid the glycol again gives off water and is converted into rhodinol. 
According to the author the alcohol prepared in this manner has a much more rose- 
like odour than has the citronellol, which is so to speak almost odourless. As another 
proof of the difference between rhodinol and citronellol, it is stated that, when oxidised, 
_the first-named affords an aldehyde, rhodinal, of which the oxime differs from citronellal 
oxime in not yielding citronellic acid nitrile when treated with acetic anhydride, and 
subsequently citronellic acid when treated with alcoholic potash, but, in concordance 
with Bouveault’s earlier experience, acetylmenthone oxime. It was found impossible 
to accomplish the converse reaction, that is to say, the conversion of rhodinol into 
citronellol. 
We intend later on to deal in detail with this matter on the basis of results 
obtained by us from experiments on the same subject. 
Linalool. E. Ferrario and M'le Xiesopolska*) stated at the meeting of the Sociétés 
de chimie de Genéve et de Lausanne, held on July 9, 1913 that they have succeeded 
in preparing linalool synthetically by reacting with vinylmagnesium bromide upon 
natural methylheptenone. Up to the present no further particulars of this synthesis 
appear to have been published. 
Menthol. By heating dimethylcinnamic acid in the liquid form with twice the 
theoretical quantity of menthol, hydrogen chloride, being occasionally passed through, 
H. Rupe, H. Steiger and F. Fiedler*) obtained the methylester of this acid in the form 
of a colourless, viscous oil, boiling at 198° (14mm.). The body thus obtained was 
not wholly pure; it still gave a faint chlorine-reaction. 
p-Menthonol. A. Kétz*) reports a synthesis of methyl-1-csopropyl-4-cyclohexa- 
none-3-ol-2 (p-menthonol). He started from methyl-1-isopropyl-4-cyclohexanone-3-carb- 
oxylate-4, which he converted into methyl-1-isopropyl-4-chloro-2-cyclohexanone-3-carb- 
oxylate-4. By boiling with a hot saturated potash solution the chlorine of this 
*) Berl. Berichte 29 (1896), 907. — *) Chem. Ztg. 37 (1913), 1122. — %) Berl. Berichte 47 (1914), 71. — 
*) Liebigs Annalen 400 (1913), 55. 
