Alkyl-and Functionalized Alkylthiophenes

摘要: Alkylthiophenes are prepared from alkanes, alkenes and alkadienes, sulfur, hydrogen sulfide, carbon disulfide other sulfur-containing reagents, using various types of catalysts high temperatures. These methods mostly technical interest. by dehydrocyclization dialkyl sulfides. A classical method, still very useful for the preparation alkylthiophenes, is action sulfide on 1, 4-difunctionalized acyclic compounds. Many different can be used alkylthiophenes thiophene alkenes, such as zeolites, zinc dichloride, aluminum trichloride, sulfuric acid, phosphoric boron trifluoride etherate. Care has to taken not work a large scale concentrations reaction go out hands. It better use dimethyl sulfate than methyltosylate methylating agent latter reacts more slowly, giving instable lithium derivatives an opportunity rearrange. Alternatively obtained thienyllithium with trialkyl boranes.