The reaction of formaldehyde on phenols: 0.
Its tetramethyl-diamino derivative, which is formed by condensing formaldehyde with dimethyl-meta-aminophenol and subsequent elimination of water from the resulting diphenyl methane derivative, is the leuco base of pyronine, into which it passes by oxidation.
The original hypothesis of Baeyer suggested that the course of events is the following: the carbon dioxide is decomposed into carbon monoxide and oxygen, while water is simultaneously split up into hydrogen and oxygen; the hydrogen and the carbon monoxide unite to form formaldehyde and the oxygen is exhaled.
The formation of formaldehyde has till recently not been satisfactorily proved, though it has been obtained from certain leaves by distillation.
It was formerly thought that its action was due to the setting free of formaldehyde in the urine, but it is now known by the researches of P. Cammidge that this is not so.
The first chemical change suggested is an interaction between carbon dioxide and water, under the influence of light acting through chlorophyll, which leads to the simultaneous formation of formaldehyde and hydrogen peroxide.
The chief aldehydes are shown in the following table: - For formaldehyde see Formalin.
The steps which lead from the appearance of formaldehyde to that of the first well-defined carbohydrate are again matters of speculation.
Knorr, Ann., 1886, 236, p. 69) or from aniline, acetone, formaldehyde and hydrochloric acid (C. Beyer, Jour.
Soc., 18 9 8, 73, p. 35 2) as a colourless liquid by the addition of hydroxylamine hydrochloride to an aqueous solution of formaldehyde in the presence of sodium carbonate; the resulting solution was extracted with ether and the oxime hydrochloride precipitated by gaseous hydrochloric acid, the precipitate being then dissolved in water, the solution exactly neutralized and distilled.