Search results
Results from the WOW.Com Content Network
Thiophene is a heterocyclic compound with the formula C 4 H 4 S. Consisting of a planar five-membered ring, it is aromatic as indicated by its extensive substitution ...
Thieno[3,2-b]thiophene. In organic chemistry, thienothiophene is any of several compounds consisting of two fused thiophene rings. They have the molecular formula C 6 H 4 S 2. Three constitutional isomers have been synthesized: thieno[3,2-b]thiophene, thieno[2,3-b]thiophene, and thieno[3,4-b]thiophene. The other isomer features S(IV) and is ...
Included are pyridine, thiophene, pyrrole, and furan. Another large class of organic heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of pyridine, thiophene, pyrrole, and furan are quinoline, benzothiophene, indole, and benzofuran, respectively. The fusion of two benzene rings gives rise to a third ...
A carbocation mechanism is inferred from the structure of 3-(4-octylphenyl)thiophene prepared from ferric chloride. [33] Polymerization of thiophene can be effected by a solution of ferric chloride in acetonitrile. The kinetics of thiophene polymerization also seemed to contradict the predictions of the radical polymerization mechanism. [63]
The Fiesselmann thiophene synthesis is a name reaction in organic chemistry that allows for the generation of 3-hydroxy-2-thiophenecarboxylic acid derivatives from α,β-acetylenic esters with thioglycolic acid and its derivatives under the presence of a base. The reaction was developed by Hans Fiesselmann in the 1950s.
As a consequence, thiophene exhibits few properties expected for a sulfide – thiophene is non-nucleophilic at sulfur and, in fact, is sweet-smelling. Upon hydrogenation, thiophene gives tetrahydrothiophene, C 4 H 8 S, which indeed does behave as a typical sulfide.
Both unsubstituted and substituted tetrahydrothiophenes are reported to occur in nature. For example, tetrahydrothiophene occurs as a volatile from Eruca sativa Mill. . (salad rocket) [5] while monocyclic substituted tetrahydrothiophenes have been isolated from Allium fistulosum 'Kujou', [6] Allium sativum (garlic), [7] Allium cepa (onion), [8] Allium schoenoprasum (chives), [9] and Salacia ...
The amide structure of articaine is similar to that of other local anesthetics, but its molecular structure differs through the presence of a thiophene ring instead of a benzene ring. Articaine is exceptional because it contains an additional ester group that is metabolized by esterases in blood and tissue. [2]