- (b.p. 119 to 121° [28 mm.]; days 0.9156; ‘uae 4666: mat -refr. 4 
_ obtained must be according to this, a AY Sn- mentnndiene: avy. 
tag ine synthesis, of menthadienes from ‘thymol and e: 
shortly — reproduced here: 
water by pene with oxalic acid gives An Ne & ‘167 t 
en ientiadiens i means of alesiolte patashi Bee i 
The hydrocarbon CipHis obtained from me-Taenibank 6-01 (I) might 
thene ug or A°-menthene (lil). The constitution of this. compe 
The compound is a colourless, pleasant smelling liquid (b. p. 169 to 171° 200 ( 
Np2»0 1.47270; mol. refr. 44.89; calculated 45.24). With sulphuric acid it giv = 
with sulphuric acid and -alcohol, a reddish-brown; and with acetic. ani ri 
sulphuric acid a violet coloration. The substance probably polymerises on 
After 7 days the purified compound had the following ‘constants: a 
Npwo 1.47437, mol. refr. 44.44. anes | ce 
the presence of two conjugated double fnkihs.. The Molecule releaeneen was. 
normal and the exaltation to be expected was not forthcoming; the molecular dis 
on the contrary, speaks for the ae ane system. The observation stands i in we 
than from the molecular reRactan. ye Re” 
CH=(CHs)2 a | | ae Oe ee 
<) OH cH Hp 
Ce 
(1) m-Menthan-6-ol. tik ai APonetenthon. te 
, roa : ¥ e * ‘ CoFls ie ; 
eg RAPES | | age. CH, oe 
CHs—C fe >CH Oe Pe Oran AL 
te NGS Se era am, CREE 6 fs \ Ce ae cH ee 
(III) A®-m-Menthene. a | (Iv) A® ee ‘ee 
for a seartinn and laste Spuiis denounce eeoeone ‘Stadiad: romae 
P. Sabatier, A. Mailhe, and G. Gaudion investigated the ee of (fey | 
nickel, cobalt, and iron on pinene vapours’®). . ve 
The pinene was obtained from French feel oi by choosing 
1) Cf. Report ‘April 1918, 136. — °) Bert. site wate 
