A colorless liquid, C4 H4 S, containing an aromatic ring composed of a sulfur atom and four carbon atoms, used as a solvent and in organic synthesis.
A heterocyclic, colorless liquid, C4H4S, resembling benzene and found in coal tar.
A colorless liquid used as a solvent. The chemical properties of thiophene resemble those of benzene, which occurs with it in coal tar. Thiophene has a ring of four carbon atoms and one sulfur atom, and among its derivatives are biotin, various plant pigments, and some pharmaceuticals. Chemical formula:C4H4S.
Thus benzene, (CH) gives thiophene, (CH) S, from which it is difficultly distinguished; pyridine, (CH) N, gives thiazole, (CH) N S, which is a very similar substance; naphthalene gives thionaphthen, C 11 S, with which it shows great analogies, especially in the derivatives.
The three primary members are furfurane, thiophene and pyrrol, each of which contains four methine or CH groups, and an oxygen, sulphur and imido (NH) member respectively; a series of compounds containing selenium is also known.
Thiophene yields a similar series: isothiazole (only known as the condensed ring, isobenzothiazole), thiazole, diazosulphides, piazthioles, azosulphimes and thiobiazole (the formulae are easily derived from the preceding series by replacing oxygen by sulphur).
Thiophene also gives rise to triazsulphole, three nitrogen atoms being introduced.
One or two benzene nuclei may suffer condensation with the furfurane, thiophene and pyrrol rings, the common carbon atoms being vicinal to the hetero-atom.