Molecular design, synthesis and structure-property relationship of oligothiophene-derived metallaynes

A series of conjugated bimetallic complexes and their polymeric analogues containing alkyne-functionalized α-coupled oligothiophenes have been synthesized and characterized. The introduction of transition metal centers, with their large variety of ligand environments and oxidation states, can impart interesting physical, optoelectronic and structural properties on these oligothiophene systems. It was demonstrated that π-conjugation of organometallic alkynyl units into the oligothiophene chain offers intriguing models that possess unique features that are not accessible in the classical organic counterparts. The photophysical, electrochemical and structural properties of these classes of metallaynes have been extensively investigated in terms of the type of metal centers and the number of oligothienyl rings within the bridging ligand. The experimental results have also been correlated to the theoretical data obtained by molecular orbital calculations using density functional theory.