180 
IOWA ACADEMY OF SCIENCE 
Auger also points out that when the succinyl chloride is. 
treated with benzene and aluminium chloride, it gives two prod- 
ucts, mainly, however, one, to which he gives the unsymmetri- 
cal formula (IV) on the ground that when saponified with 
barium hydroxide, it gives not the original succinic acid, but 
a diphenyl derivative, a monobasic acid, which may be formu- 
lated (V), while the isomeric product, which may be ten per 
cent of the total, is not acted upon. 
IV V 
CH.-CHCeHs). CH,-C=(CeH5). 
I I 
I I 
CR,—C=0 CH 3 -COO(ba) 
The analogy is carried to the phthalic acids which, according 
to Auger, occur only in the unsymmetrical form. D. Vorlander® 
has objected to the idea of isomeric chlorides. He explains the 
action of the imine on the basis of the formation of an isomer 
of an amido acid. 
OH 
CHg— C=NH 
I 
CHg— COOH 
CH2-C=0 
I ^NH+HgO 
CHs— C=0 
He objects to any form of reasoning through the use of th& 
acid chloride with benzene where a. substance like aluminium 
chloride is involved in the reaction. However, the isolation of 
the ortho sulphobenzoic acid chlorides in two forms as carried 
on by Remsen and his pupils, has put an end to any doubt which 
there may have been regarding the existence of two separate 
distinct acid chlorides in such cases, and has strongly reflected 
credit on the work of Auger. We shall use the terms symmetri- 
cal and unsymmetrical in the same sense in which he used them. 
It was formerly stated^® that the treatment of the potassium 
salt of the 4-nitro-5-methyl-2-sulphobenzoic acid with phosphor- 
ous pentachloride in a flask with reflux condenser at boiling 
temperature produced an oily substance which solidified with 
difficulty, but on being dissolved in carbon tetrachloride, dried, 
and partly evaporated, gave two products, one melting at 133°, 
the other an oily substance for which a melting point of 93° 
was suggested. It had been the experience of others that the 
»Ber., 30, 2268, 1897. 
^®Loc. cit. (Karslake and Bond.) 
