- 87 - 
The Other hydrocarbon, trimethyl-i, i, 5-ethenyl-2-cyclopentene-4, 5, 
isomeric with camphene, is produced in an analogous manner from 
a-camphylamine. The quaternary ammonium iodide Cg H^g C • 
N(CH3)3l, melts with decomposition at 285°. This hydrocarbon 
is a mobile liquid with a camphene - like odour, and the boiling 
point 157° to 158° The tertiary base Cg H^g CH2 • CH2 N(CH3)2 
which is formed in an analogous manner to the one mentioned above, 
has a fish-like odour, and boils at 215°. Its hydrochloride crystal- 
lising in leaflets melts with decomposition. The following diagram 
represents the constitution of trimethyl-i, i, 5-ethenyl-2-cyclopentene: 
C.CH. 
CH 
CH3.C.CH3 
CH, 
CH 
CH 
Phellandrene. In order to clear up the constitution of phellan- 
drene, Semmler^) oxidised the crude hydrocarbon (from eucalyptus 
oil) at reduced temperature with a quantity of potassium permanganate 
corresponding to 4 atoms oxygen. On then distilling the oxidation 
product with steam, he obtained an oil containing cineol and cymol. 
In the residue there was present a mixture of non- crystallising acids, 
which could be separated by means of copper acetate. From the 
insoluble copper salt, a-oxy-/?-isopropyl glutaric acid CgH^^Og was 
obtained, which on further oxidation with peroxide of lead yielded 
1-isopropyl succinic acid Crjll^2^i with the following constants: boiling 
point == 138° to 140° (at 19 mm); n^ = 1,4519; = — 3°; 
^20° = 1. 105; niol- I'efr. = 34,7. 
The soluble copper salt was that of an a-oxy-isopropyl adipic 
acid CgH^gOg which was oxidised by peroxide of lead into 1-a-iso- 
propyl glutaric acid CgHj^404, whose physical constants are: boiling 
point = 155^ to 160° (at 19 mm); n-p = 1,4613; m. p. = 94° to 95°; 
dgQO = 1,088; mol. refr. = 39,2. 
The mixture of the crude acids could also be separated in this manner, 
that it w^as further oxidised direct with peroxide of lead, and the acid 
mixture thus obtained precipitated at boiling heat with calcium chloride. 
Calcium isopropyl succinate thereby separated off in an insoluble state. 
Semmler concludes from these results, that crude phellandrene 
consists of a mixture of two hydrocarbons. If two double linkings 
^) Berichte 36 (1903), 1749. 
