™, Te" 
qe inning, ; a es salt ae as Ptecnedie SrdieL but in fie course of the bexeHon 
a dark red liquid results which, on standing, separates into two unequal layers. After 
3 all the magnesium methyl bromide has been added, the mixture is allowed to stand 
_ for an hour and then decomposed by means of icy cold solution of ammonium chloride. 
In order to eliminate completely the halogenous bodies, the rectified product is boiled 
for 4 hours with 1 vol. of ethyl alcohol and 1 vol. of methyl alcoholic potash. Methyl- 
s 
= 
3 
methylenecamphor free from halogens melts between 28 and 29°; b.p. 109 to 110° 
(12 mm.); [e], + 178.58° (solution of about 10 per cent. in benzene). The smell is 
aromatic, camphor-like. Some crystalline bodies, melting between 280 and 281°, and 
183 and 184°, had formed as by-products. Methylmethylenecamphor cannot be purified 
_ through distillation over sodium, as it then decomposes, forming camphor and a bua 
melting between 169 and 170°. 
é C:CH-CH,-CH 
Pace yatiesis of ethylmethylenecamphor (propylidenecamphor), CsH; oe a8 2° ) e 
is carried oat like that of the methyl derivative just described, by the action of mag- — 
nesium ethyl bromide on chloromethylenecamphor. It forms a colourless, aromatic oil,. 
boiling between 121 and 122° (13 mm.); da. 0.9448; [o]pno -+ 172.95° (in alcoholic 
solution of about 10 per cent. +-171.26°; in a benzene solution of about 10 per cent. 
+ 157.44°); np 1.49042. The purification of the crude product, containing chlorine, 
with the aid of alcoholic potash proved to be accompanied by a considerable loss; 
an attempt to eliminate the chlorinated products by treatment with aluminium amalgam — 
led again to the substance melting between 169 and 170°. 
y C:CH: CH2:CH es 
. n-Propylmethylenecamphor (n-butylidenecamphor), CsHu< ; Co pee 
boils between 131 and 132° (12 mm.); das 0.9380; &p»0 + 161.959; np 1.48946. The 
product had been obtained free from chlorine by boiling with alcoholic potash and 
distilling over metallic sodium. 
y ©:CH: CH: CH(CHs)2 
Zsobutylmethylenecamphor (Isoamylidenecamphor), CoH 2G ee Ne 
“may be freed from chlorine by boiling witn alcoholic potash and distilling over sodium. 
B. p. 136 to 138° (12 mm.); dee 0.9275; [@]px%0 + 156.09°; np 1.48772. It forms a rather 
liquid, aromatic oil. It yibided on ozonization camphorquinone (m. p. 198°), camphoric 
acid (m. p. 186 to 187°) and isovaleric acid (b. p. 173 to 1749). 
The action of magnesium allyl bromide on chloromethylenecamphor did not lead 
to the expected camphor derivative, but to a mixture of hydrocarbons. On the con- 
trary, from magnesium phenyl bromide and chloromethylenecamphor, phenylmethylene- 
se: CH: CoH . 
camphor?) (benzylidenecamphor), CsHuc ; CO : . was obtained in the usual way. 
M. p. 98.59; [4]px0 + 426.55° (solution of about 10 per cent. in benzene). 
C:CH-CH2: C,H 
Benzylmethylenecamphor (phenylethylidenecamphor), CoH ¢ ¢ 0 rise Z boils 
between 124 and 126° (0.1 mm.); dS 1.0250; ely 120: Np 1.54948. It was ac- 
companied by a body boiling Benieen 143 and 144.5° (14 mm.), presumably of the 
formula Ci2HiO. When submitted to ozonization, benzylmethylenecamphor gave 
1) This compound has been previously described by Haller and March. Compt. rend. 142 (1906), 316; 
Report April 1906, 101. 
