Nov. 24 ,1923 
Studies on Rancidity 
347 
hydrochloric acid; and somewhat more soluble, possibly with decom¬ 
position, in alkaline solutions. The solubility in all of these solvents 
seemed to be too small for purposes of crystallization. The substance 
also appeared to char before it melted. No indication could be obtained, 
therefore, as to its probable purity. It was nevertheless dried to con¬ 
stant weight at a temperature of 105° C. and analyzed with the following 
results: 
c. 
H. 
Cl. 
I. 
Per ct. 
61. 34 
61.02 
61.18 
Per ct. 
Per ct. 
1. 79 
1. 76 
1. 77 
2 . 
Average. 
4 * TO 
If the chlorin were an integral part of the molecule, then the molecule 
must be an extremely complicated structure with a molecular weight 
of about 2,000, whereas the phloroglucid of epihydrin aldehyde would 
be expected to have a molecular weight of less than 200. It seems prob¬ 
able, therefore, that the chlorin is present as an impurity in the form of 
adsorbed hydrochloric acid, and on this assumption the following revised 
analytical results have been calculated : 
c. 
H. 
Found 1. 
Per ct. 
62. 48 
62. 16 
62.32 
Per ct. 
4 * 53 
4.48 
4 * 5 ° 
2. 
Average. 
CjgH^Oj... 
62.49 
62.05 
4. 20 
4. 86 
CikHiaO*. 
While the revised analytical results correspond somewhat more closely 
to the formula C 15 H 12 0 6 than to C 15 H 14 0 6 , they are not sufficiently close 
to either to indicate a decided choice between them. As a matter of fact 
they correspond almost exactly to the composition of an equimolecular 
mixture of the two compounds. 
The compound C 15 H 14 0 6 , however, could not very well result from the 
condensation of epihydrin aldehyde and phlorogludn except through a 
process of reduction, and according to von Euler (12) color formation in 
similar condensations is generally due to oxidation rather than to reduc¬ 
tion. On the other hand, a compound C 15 H 4 O e would be expected to 
result from the condensation of acrolein and phloroglucin. 
CH a : CH.CHO+2C 8 H 3 (OH) 3 -» CH* : CH.CH : [QH^OHJsh+HaO. 
But whereas some acrolein phloroglucid might well have been formed 
from uncombined acrolein in the preparation of our analytical material, 
the acrolein phloroglucid has already been found by experiment to differ 
in color from the red phloroglucid which is obtained equally well from the 
acetal of epihydrin aldehyde and from mixtures of acrolein and hydrogen 
peroxid. 
