Synthesis, characterization and investigation of optical properties of acrylonitrile substituted spirocyclotriphosphacenes: Device fabrication

In this thesis, first of all methoxy-substituted phenylacrylonitrile compounds 4-MeO-Ph-AN-Ar were synthesized by the Knoevenagel condensation reaction, and then the demethylation of the 4-methoxy group in these compounds was carried out using a microwave method to optain 4-hydroxy-substituted phenylacrylonitrile 4-HO-Ph-AN-Ar compounds. Subsequently, spirocyclictrifosphazene compounds were synthesized in the intermediate stage by reacting 2,2-dichloro-4,4,6,6-bis[spiro(2',2″-dioxy-1',1'-biphenyl)]cyclotriphosphazane (BPP) and 2,2,4,4-tetrachloro-6,6-bis[spiro(2',2"-dioxy-1',1"-biphenyl)]cyclotriphosphazane (DPP) with hexachlorocyclotriphosphazane (HCCP) in the presence of 2,2'-biphenol. Finally, the reactions of the obtained 4-HO-Ph-AN-Ar derivatives with DPP and BPP compounds resulted in the synthesis of DPP-4-O-Ph-AN-Ar and BPP-4-O-Ph-AN-Ar which are acrylonitrile substituted spirocyclictrifosphazene compounds. The structures of all intermediate and final products were characterized by FT-IR, 1H-NMR, and 13C-APT-NMR spectroscopic techniques. Additionally, 31P-NMR and mass spectrometry (MALDI-TOF MS) were used to characterize the final spirocyclictrifosphazene compounds. The thermal stability and optical properties of the obtained acrylonitrile substituted spirocyclictrifosphazene derivatives were thoroughly investigated. Based on the data obtained, appropriate comments were made regarding the production of stable and high-performance organic semiconductor materials for the design of optoelectronic devices (such as diodes, photodiodes, and solar cells). A Schottky diode is fabricated.