991 
The suspicion now arose that the (readily obtainable) Na-formyl- 
acetic ester would react with cyanacetic acid as follows: 
A | H 
ie joe 
CH, + CH — EtOOC.CNa(CN).CH = CH.COOEt + H,O 
| 5 
COOEt COOEt (Ethyl « cyano glutaconate). 
This indeed appeared to be so. 
60 grams of Na-formylacetie ester (which according to a statement 
in the literature only consists of the desired compound to the extent 
of about 70 °/, 
diately afterwards 45 grams of cyanoacetic ester were added and the 
whole heated on a boiling waterbath for + half an hour (until 
) were dissolved in 150 ce. of absolute alcohol. Imme- 
the decomposition sets in). The yellow gelatinous contents of the 
flask were then taken up with dilute hydrochloric acid and the 
liquid shaken with ether. After washing with dilute soda solution 
and water the ether was evaporated. The result was 380—35 grams 
(+ 45°/, of the theory) of a pale yellow, very thick viscid oil. 
In its properties this ester completely resembled the a-cyanoglu- 
taconic ester obtained by Gurazerr and Eyssen') from 7so-imidodi- 
carboylglutaconic ester with e-cyanoglutaconic ester prepared with 
aqueous sodiam hydroxide. It had a very bitter taste, gave a carmine- 
red colour with ferrichloride in alcoholic solution and could not be 
distilled under any circumstances. *) 
By saponifying the ester with acids or alkalis Guruzeir and Eyssen 
could isolate nevther glitaconic acid nor any other product of hydro- 
lysis. I have myself tested this saponification with dilute potassium 
hydroxide, potassium methoxide, hydrochloric acid (10°/, HCD, 
concentrated sulphuric acid and 30°/, hydrogen peroxide + potassium 
hydroxide and tested the reaction fluids carefully with regard to the 
presence of glutaconic acid, malonic acid ethyl-2.6-dioxypyridine.5. 
carboxylate, 2.6.dioxypyridine.5.carboxylic acid and 2.6.dioxy pyridine, 
all products which might be expected here in consequence of the 
research of THorpr and Roeerson. The result, however, was always 
negative. 
The acid thus prepared is, therefore, certain to have another 
structure. Probably it possesses an iso-vmido structure: for instance 
1) J, pr. Chem. (2) 80. 34 (1909). 
*) The cyanoaconitic esters prepared by ErreRA PascraBosco (Ber. 34, 3704) 
cannot be distilled even in vacuum without decomposition. 
} 64 
Proceedings Royal Acad. Amsterdam, Vol. XVIIL 
