The true nitrile of malonic acid is methylene cyanide, CH 2 (CN) 2, which is obtained by distilling a mixture of cyanacetamide and phosphorus pentoxide.
It is a most important synthetic reagent; with sodium or sodium ethylate it forms sodio-malonic ester, which reacts readily with alkyl halides, forming alkyl malonic esters, which are again capable of forming sodium derivatives, that by further treatment with alkyl halides yield the di-alkyl malonic esters.
Herrmann, Ann., 1882, 211, p. 306; also see below, Configuration of the Benzene Complex); the condensation of acetone dicarboxylic ester with malonic ester to form triketohexamethylene dicarboxylic ester (E.
Of foremost importance are the reactions termed the malonic acid and the aceto-acetic ester syntheses; these are discussed under their own headings.
Potassium bichromate oxidizes it to malonic acid; nitric acid oxidizes it to oxalic acid; and hydriodic acid reduces it to succinic acid.
Riiber (Ber., 1902, 35, p. 2411; 1904, 37, P. 22 74), by oxidizing diphenyl-2.4-cyclo-butane-bismethylene malonic acid (fron cinnamic aldehyde and malonic acid in the presence of quinoline) with potassium permanganate.
Crotonic acid, so named from the fact that it was erroneously supposed to be a saponification product of croton oil, may be prepared by the oxidation of croton-aldehyde, CH3 CH:CH CHO, obtained by dehydrating aldol, or by treating acetylene successively with sulphuric acid and water; by boiling allyl cyanide with caustic potash; by the distillation of 0-oxybutyric acid; by heating paraldehyde with malonic acid and acetic acid to, oo C. (T.
From the nitroacetic acid obtained above, malonic acid was prepared, and from this a monochlormalonic acid was obtained; we assume the chlorine atom to replace the c hydrogen atom.
The oxyderivatives of the tetrahydroand hexahydro-pyrimidines are the uracils and the ureides of malonic acid (see PuRIN).
Many esters of malonic acid have been prepared, the most important being the diethyl ester (malonic ester), CH 2 (000C 2 H 5) 2, which is obtained by dissolving monochloracetic acid in water, neutralizing the solution with potassium carbonate, and then adding potassium cyanide and warming the mixture until the reaction begins.