Pyridin-thiophene derivatives: Synthesis, characterization and electrochemical behavior on graphite pencil in atmospheric condition

•The synthesis of eight new nonsymmetric thiophene monomers, featuring a pyridin-type substituent in α or β position, is described.•These structures were thoroughly analyzed using both 1D and 2D experiments.•Cyclic voltammetry experiments demonstrated the redox activity of all thiophene derivatives, with current intensities reaching up to 0.86 mA.•An eco-friendly method for the electrochemical polymerization of these compounds is also reported.•HB2 graphite pencil was used as the working electrode instead of expensive noble metal electrodes.•Polymeric thiophene films were deposited under atmospheric conditions in a mixture of acetonitrile and sulfuric acid, exhibiting remarkable stability. A new family of eight benz(imida, oxa and thiazole)-pyridin-thiophene derivatives was synthesized via the Suzuki-Miyaura reaction conditions. Once the structures of all compounds were confirmed by 1D and 2D Nuclear Magnetic Resonance (NMR) analyses, electrochemical studies using Cyclic Voltammetry (CV) revealed enhanced redox activity. Under our experimental conditions, a solvent mixture of acetonitrile and sulfuric acid played a key role in boosting the electrochemical response, yielding anodic current values of up to 0.86 mA. For direct comparison, we also synthesized the parent pyridin-thiophene compounds, which exhibited anodic current values of up to 0.72 mA. Those values are significantly higher than the 0.002 mA observed for analogous materials synthesized in dry acetonitrile and ammonium salt mixture under nitrogen atmosphere. The electrochemical response of the synthesized compounds is comparable to that of commercially available monomers 3,4-ethylenedioxythiophene (EDOT) and bithiophene (BiThio), which could be exploited in the production of conductive organic films with diverse optoelectronic applications. [Display omitted]