A luminescent 2,2′-bipyridyl tricarbonyl rhenium(I) complex containing a non-bridging dicyanamide ligand

fac-(bpy)Re(CO)3CF3SO3 reacts with sodium dicyanamide in THF/MeOH/H2O to give fac-(bpy)Re(CO)3N(CN)2 (1) in 81% yield. Complex 1 was characterized spectroscopically and electrochemically using NMR, IR, UV–Vis, fluorescence and cyclic voltammetry. Complex 1 crystallizes in the P21/c space group with a=7.2004(3) Å, b=12.9547(5) Å, c=16.8523(6) Å, β=101.989(1) °, and Z=4. Photophysical measurements indicate the π-acceptor ability of N(CN)2− as equivalent to that of the 4-N,N-dimethylaminopyridine ligand. Strong luminescence is observed in solution at room temperature and in 4:1 ethanol:methanol matrices at 77K attributed to the 3MLCT state.