__ borny! acetate in addiiba © % camphene on. being heated with 
and glacial acetic acid. 
identical camphene hydrate. As no transposition need be suspected, owing to th 
action of the milk of lime, he thinks that the chlorides in question, viz., cam 
hydrochloride, bornyl chloride and isobornyl chloride are likewise identical+). ~ 
On being boiled with acetic anhydride, camphene hydrate is partly conveliea: 
the acetate, boiling between 103 and 105° (14 mm.); diso 0.9852. Methyleamphenilo 
forms an acetate boiling between 100 and 102° (11 mm); dZ5 1.003; [¢]p + 18.99. 
While methylcamphenilol is but slightly attacked by boiling glacial acetic acid, cam- 
phene hydrate is almost entirely converted into camphene. 
On isopulegolphosphonic acid, see page 121 of this Report. 
Aldehydes. 
Phytochemical reduction of citronellal to citronellol. 
In former Reports, we have discussed already C. Neuberg and his collaboraiens 
publications on the phytochemical reduction of aldehydes to alcohols with the aid of 
yeast”). Neuberg’s latest works have been compiled together with E. Schwenk, P. Mayer 
and M. Ringer*). They refer to the reduction of glycolaldehyde to ethyleneglycol, the 
transformation of ethyl disulphide into ethylmercaptane, that of citronellal into citronellol, 
the succinic acid fermentation of the @-ketoglutaric acid and the formation of succinic 
acid from decaying «-ketoglutaric acids. . 
_In order to reduce citronellal, Neuberg and Mayer filled four 5 litre bottles ithe 
250 g. of cane sugar, 2500 cc. of water of 40° and 250 g. of yeast (Unterhefe Ge: 
As soon as the fermentation was vivid, 12 cc. of d-citronellal, dissolved in 13 cc. of 
absolute alcohol, were added to each bottle. After vigorous shaking, the fermentation : 
soon stopped but started again after 10 minutes. As the citronellal floats on the sur- 
face, the shaking must be repeated frequently. All the four bottles were at first kept a 
at 30° for twelve hours and then at room temperature during the night. The fermentation a 
remained feeble, although the bottles were afterwards placed in an incubator (37°), an é 
it was, therefore, roused by adding another 150 g. of cane sugar and 150g. of yea: 
) (Hefe K). A very slow fermentation resulted, but it extended over a fortnight. Th 
content of the bottles, which had been closed with cotton wool stoppers, was vigorousl 
| shaken at least three times daily, when the whole incubator filled with the typi 1 
rose odour. After 15 days, the whole content of the four bottles, which had remainec 
absolutely sterile, was distilled with steam and the distillate treated with ether. T 
residue of the extraction was treated with sodium hydrogen sulphite solution, in 
_ to remove the possibly present citronellal, and then fractionated in vacuo 
-_ d-citronellol thus obtained boiled between 107 and 110° (11 mm.); [e]puo - 
The silver salt of the ester of the citronellyl phthalic acid melted at 123°, #3 
= See ofl ah ie ar 
t . ¢ om. 
1) See A. Hesse, Berl. Berichte 89 (1906), 1127; Report October 1906, 113. — Di See ‘Rosi sf 
128; April 1915, 91; October 1915, 82. — 1) Biochem. Zeitschr. 71 ea, 114, 117, we 226 
