Synthesis, Characterization and Photophysical Properties of Thiophene-containing Chloro Re(I) Complex

Two tricarbonyl rhenium complexes with the formula of [Re(CO)(3)(L)Cl], where L=1,10-phenanthrol me (Phen-Re) and 2-(3-thienyl)-imidazo[4,54]-1,10-phenanthroline (TIPh-Re), were successfully synthesized and characterized by H-1 NMR and UV-Vis with the aim to analyze the effect of the thiophene(TI) moiety on the photophysical properties of TIPh-Re. It was found that the introduction of an pi-electron density moiety into diimine ligands leads to a dramatic red shift of the absorption of the corresponding Re(1) complex. At the same time, the results verify that the triplet metal-to-ligand charge-transfer d pi(Re)->pi*(N-N) emission ((MLCT)-M-3) of Phen-Re and TIPh-Re centered at ca. 566 nin and ca.569 nm, respectively.