With the intention of taking up pharmacy he entered Heidelberg University about 1835, and after graduating went to Giessen as preparateur to Liebig, with whom he elucidated the composition of paraldehyde and metaldehyde.
It is readily polymerized, small quantities of hydrochloric acid, zinc chloride, carbonyl chloride, &c. converting it, at ordinary temperatures, into paraldehyde, (C 2 H 4 0) 3, a liquid boiling at 124° C. and of specific gravity oï¿½998 (15° C.).
Paraldehyde is moderately soluble in water, and when distilled with sulphuric acid is reconverted into the ordinary form.
Metaldehyde, (C 2 H 4 0) 3, is produced in a similar way to paraldehyde, but at lower temperatures (e.g.
Paraldehyde is oxidized by dilute nitric acid, with formation of much glyoxal, (CHO) 2.
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.
The substance investigated was acetaldehyde, C 2 H 4 O, in its relation to paraldehyde, a polymeric modification.
The phenomena were first observed without mutual transformation, aldehyde melting at - 118°, paraldehyde at 13°, the only mutual influence being a lowering of melting-point, with a minimum at - 120° in the eutectic point.
In that mixture which contains 88% of paraldehyde and 12% of acetaldehyde, which the catalytic agent leaves unaffected.
PARALDEHYDE, in medicine, a clear colourless liquid (for the chemistry see Aldehydes), soluble in i in 10 of water and freely in alcohol.
Paraldehyde is a powerful hypnotic, giving a refreshing quiet sleep which is not followed by unpleasant after effects.
When taken continuously the drug soon loses its power as a hypnotic. Its unpleasant taste usually prevents the formation of a paraldehyde habit, but it occasionally occurs with symptoms resembling delirium tremens.
When taken in an overdose paraldehyde kills by producing respiratory failure.
Amongst those which lessen excitability of the brain-cells are opium, morphine, hyoscyamus, chloral, sulphonal, trional, paraldehyde, chloralamide, chloralose, hop and many others.
Ethyl alcohol is taken as a type of the action of methyl alcohol, amyl alcohol, propyl alcohol, ether, acetic ether, paraldehyde, sulphonal, chloroform, methyl chloride, ethyl chloride, chloral hydrate, butylchloral hydrate, and almost any number of derivatives from these.
The introduction into practical use of many medicines, such as paraldehyde, phenazone and strophanthus, has followed the study of their actions on animals, and this tends to be more and more the case.
Quinaldine (a-methylquinoline) is present in coal-tar; it may be prepared by condensing aniline with paraldehyde and concentrated hydrochloric acid (0.
It may be prepared synthetically by condensing ortho-aminoacetophenone with paraldehyde and caustic soda (L.