Synthesis of 3- and 3,4-substituted some novel thiophene derivatives for producing functional conducting polymers and their polymerization

In this thesis, research on aromatic nucleophilic substitution reactions of 3,4-dibromothiophene with various nucleophiles were performed to synthesize new 3,4- substituted thiophene derivatives. For this purpose, substitution reactions of 3,4-dibromothiophene were investigated with cyano and alkoxy nucleophiles and derivatization studies was performed with obtained 3,4-dicyanothiophene.In the second part of this study, nucleophilic substitution reactions (SNAr) of 3,4-dibromothiophene with several primary and secondary amines were investigated to synthesize some novel thiophene derivatives containing nitrogen heteroatom at 3,4- positions. For optimization of reaction conditions, catalyst, base and solvent effects were examined on the model reaction between 3,4-dibromothiophene and 1-butylamine. After determining the appropriate reaction conditions, this method was applied to reaction of 3,4-dibromothiophene with different primary and secondary amines. The yields and product distribution of monoalkyllaminothiophene and dialkylaminothiophene derivatives under optimized conditions were determined. Ring closure reactions of 3,4-bis(N-butylamino)thiophene with 1,2-dibromoethane and 1,3-dibromopropane were realized and two new type thiophene derivatives have been synthesized accordingly. Characterizations of all thiophene derivatives were performed by FTIR, 1H-NMR, 13C-NMR, GCMS techniques.In the last part of the thesis, polymerization of synthesized monoalkyl-aminothiophene and dialkylaminothiophene derivatives were investigated by the electrochemical and chemical methods. Electrochemical behavior of the new thiophene derivatives were examined by cyclic voltammetry (CV) technique in different solvent-electrolyte systems. In addition, homopolymer of 3,4-bis(N-bütilamino)thiophene was prepared by chemical polymerization method using RuCl3 as oxidant and its structural characterization was performed by FTIR and 1H NMR techniques.