Anthracene Sentence Examples

Phenazone is an isomer of phenazine, to which it bears the same relation that phenanthrene bears to anthracene.

By fusing two nuclei we obtain the formula of naphthalene, C 1 oH 8; by fusing three, the hydrocarbons anthracene and phenanthrene, C14H10; by fusing four, chrysene, C18H12, and possibly pyrene, C16H1n; by fusing five, picene, C22 H 14.

Thomsen then investigated heats of combustion of various benzenoid hydrocarbons - benzene, naphthalene, anthracene, phenanthrene, &c. - in the crystallized state.

The next members are the -isomers anthracene and phenanthrene, C14H,0, formed from three benzene nuclei.

Here we shall only discuss the structure of these compounds in the light of the modern benzene theories; reference should be made to the articles Naphthalene, Anthracene and Phenanthrene for syntheses, decompositions, &c.

According to Armstrong, anthracene behaves unsymmetrically towards substituents, and hence one lateral ring differs from the other; he represents the molecule as consisting of one centric ring, the remaining medial and lateral ring being ethenoid.

For general purposes, however, the symbol (2), in which the lateral rings are benzenoid and the medial ring fatty, represents quite adequately the syntheses, decompositions, and behaviour of anthracene.

Similarly a CH group may be replaced by a nitrogen atom with the production of compounds of similar stability; thus benzene gives pyridine, naphthalene gives quinoline and isoquinoline; anthracene gives acridine and a and 3 anthrapyridines.

On passing the vapour through red-hot tubes it yields anthracene and toluene.

The crude anthracene cake is purified by treatment with the higher pyridine bases, the operation being carried out in large steam-jacketed boilers.

The whole mass dissolves on heating, and the anthracene crystallizes out on cooling.

The crystallized anthracene is then removed by a centrifugal separator and the process of solution in the pyridine bases is repeated.

Finally the anthracene is purified by sublimation.

Many synthetical processes for the preparation of anthracene and its derivatives are known.

Anthracene has also been obtained by heating ortho-tolylphenyl ketone with zinc dust C6H4(CH CH =H20+C6H4 I)C6H4.

Numerous sulphonic acids of anthracene are known, a monosulphonic acid being obtained with dilute sulphuric acid, whilst concentrated sulphuric acid produces mixtures of the anthracene disulphonic acids.

By the action of sodium amalgam on an alcoholic solution of anthracene, an anthracene dihydride, C14H12, is obtained, whilst by the use of stronger reducing agents, such as hydriodic acid and amorphous phosphorus, hydrides of composition C14H16 and C14H24 are produced.

Oxidizing agents convert anthracene into anthraquinone; the production of this substance by oxidizing anthracene in glacial acetic acid solution, with chromic acid, is the usual method employed for the estimation of anthracene.

After this treatment, the mixture is run into lead-lined vats and treated with sulphuric acid, steam is blown through the mixture in order to bring it to the boil, and the anthracene is rapidly oxidized to anthraquinone.

Liebermann in 1868 prepared that substance synthetically from anthracene, but their process was not practicable on a large scale, and it was left to him to patent a method that was commercially valuable.

For naphthalene quinones see Naphthalene; for anthracene quinone see Anthraquinone; and for phenanthrene quinone see Phena Nt H Rene.

The first step in the synthetical production of alizarin was the discovery in 1868 of C. Graebe and C. Liebermann that on heating with zinc dust, alizarin was converted into anthracene.

In practice, the crude anthracene is purified by solution in the higher pyridine bases, after which treatment it is frequently sublimed.

Thus by using benzene, benzaldehyde and anthracene are obtained.

Dewar and Jones suggest that in the latter reaction it is the metallic nickel which is probably the reducing agent effecting the change, since it is only dissolved in any quantity when the anthracene hydrocarbon is produced.

Moreover, these secondary products cannot be successfully reduced, by further heating, to simpler hydrocarbons of any high illuminating value, and such bodies as naphthalene and anthracene have so great a stability that, when once formed, they resist any efforts again to decompose them by heat, short of the temperature which breaks them up into methane, carbon and hydrogen.

But it must be here understood that each member of these condensed nuclei need not necessarily be identical in structure; thus the central nuclei in anthracene and phenanthrene differ very considerably from the terminal nuclei (see below, Condensed Nuclei).

It is prepared commercially from anthracene by stirring a sludge of anthracene and water in horizontal cylinders with a mixture of sodium bichromate and caustic soda.

In order to synthesize alizarin, they converted anthracene into anthraquinone and then brominated the quinone.