Synthesis of new building blocks for conjugated oligomers

Sammanfattning: This thesis deals with the synthesis of new organicmaterials for electronic applications. Several new ring-formingmethods are employed to construct sulphur heterocycles: Tandemelectrophilic aromatic substitution and acid-catalyzedtransetherification of methoxythiophene, double electrophilicaromatic substitutions with ethane-1, 2-disulphenyl chloride,and also, the reaction of dienes with sulphur dichloride. Twonew condensed thiophenes have been incorporated in end-cappedoligothiophenes. An improvement of the synthesis of [3,2-b:2?, 3-d]thiophene is reported, with some attempts toincorporate it in oligomers. A synthesis of substitutednaphthalenes is also described. A new method of producingdisubstituted thiophenes from substituted butadienes anssulphur dichloride is employed in a new route to 3, 4-ethylenedioxythiophene, a very important monomer for conductingpolymers.Keywords :Organic Semiconductors, Thiophenes,Heterocyclic Synthesis, Dithienothiophene, Naphthalene,Ethylenedioxythiophene