212 M. Kolbe on the Synthesis of Salicylic Acid. 
Alphatoluylic acid is oxidized, but with difficulty, with forma- 
tion of hydride of benzoyle. Strecker and Miller have prepared 
the chloride, the amide, and the nitro-compound of this acid. 
They represent its formation from vulpie acid in the following 
manner :— 
Vulpic acid. CHO) eq. Alphatoluylicacid C3? H'*O® 
+8eq.water H® OF (= Oxalic acid... <O44H?,0° 
Ce Heo’ Methylic alcohol. C? H* O? 
CH= O08 
If, in the decomposition of vulpic acid, potash be used instead 
of baryta, other products occur. Methylic alcohol distils over ; 
and when the residue is supersaturated with hydrochloric acid, 
carbonic acid is disengaged in abundance and a crystalline pre- 
cipitate formed. This is a new acid, which, when recrystallized 
from boiling alcohol, appears in the form of rhombic prisms. The 
crystals are brittle, but tolerably hard ; they melt at 154°; they 
are difficultly soluble in water, but readily so in alcohol. The 
formula of this acid is C5? H!® 0®; and the authors name it owa- 
toluylic acid. The baryta-, silver-, and lead-salts are all crystal- 
lized, and are monobasic. Oxatoluylic ether, C®* H!® (C4 H®) 06, 
is best obtained by the action of iodide of ethyle on the silver- 
salt. It forms colourless prismatic crystals, which melt at 
45°-5. By the action of nitric acid on the acid, a nitro-compound 
is formed. The formation of oxatoluylic acid is as follows :-— 
Vulpic acid . C** H!4 01° CHS OQ Oxatoluylic acid. 
Water “2% H® O° | —C? H* O? Methylic alcohol. 
C38 20 Ole C4 O® Carbonic acid. 
C38 2 O16 
When boiled with strong potash, oxatoluylic acid readily un- 
dergoes a further change ; it becomes converted into oxalic acid 
and toluole. From this deportment it appears to have received 
its name. The decomposition may be thus expressed :— 
C2 H16 064 2HO=C* H208+2C" HB, 
Oxatoluylic acid. Oxalic acid. Toluole. 
The difference in the decomposition of vulpic acid by potash and 
by baryta is remarkable as showing a great mobility of the atoms. 
It appears probable that the insolubility of oxalate of baryta is 
the determining moment in the first reaction, as is frequently 
observed in double decompositions of salts. 
Salicylic acid, C!4 H® 0, has been considered by Kolbe to have 
a constitution analogous to that of carbovinic acid; in short, to 
be carbophenylic acid,— 
