142 0. L. Jackson—Methyl and Benzyl Compounds. 
alcohol. It saves time to make a first rough separation with 
ether, in which the monoselenide is the most soluble. 
Calculated for (CH;),Se. Observed. 
Carbon - -_- | _..64°62 63°15 63 
Hydrogen --_--. 5°38 5°54 5°56 
If an excess of benzyl chloride is used, a yellow oily liquid 
is obtained, which after some time deposits the benzyl mono- 
selenide in large well-formed flat prisms apparently belonging 
to the monoclinic system. These, as well as the white needles 
deposited by the alcoholic solution, melt at 45-°5 (uncorr.) and 
burn with a smoky flame, which shows the blue color charac- 
teristic of selenium. It has very little odor, is insoluble in 
water, freely soluble in alcohol and ether. 
verted by heating gently with strong nitric acid into a white 
mass, which formed on crystallization from hot alcohol well- 
marked little rhombic crystals. Melting-point 88° (uncorr.). 
It is almost insoluble in water and ether, freely soluble in hot 
alcohol, less so in cold. Its solutions decompose very easily, so 
that the greater part of the substance disappears on recrystal- 
lization. 
Chloride of Benzyl Selenide. An alcoholic solution of the 
nitrate gave with hydrochloric acid a white precipitate which 
yielded yellow or brown needles on recrystallization from. 
alcohol. It consists of branching needles either yellow or 
brown ; the color, however, is probably due to partial decomposi- 
tion, as it is extremely unstable, being decomposed even below 
the boiling point of alcohol into selenium and benzyl chloride. 
It is slightly soluble in hot alcohol, and its solution is even 
more unstable than that of the nitrate. : 
An alcoholic solution of nitrate of benzyl] monoselenide 
treated with hydrobromic acid gave selenium, and vapors which 
attacked the eyes violently, and were probably benzyl bromide 
C,H,CH,Br. It seems, therefore, that the chloride and 
bromide of benzylselenide are decomposed according to the 
following reaction : 
(C.H,),SeBr, =2C,H,Br+Se, 
while the bromide and iodide of methylselenide undergo an 
entirely different decomposition : 
(CH,),SeBr, =(CH ,),Se+Br,. 
It is interesting that the replacement of one atom of hydrogen 
