Syntheses, structural studies and spectroscopic characterisation of pyridyl–phthalimide complexes of fac-(CO)3ReI-diimines

The mono-dentate ligands, 3-aminomethyl-N-phthalimido-pyridine (L1) and 3-amino-N-phthalimido-pyridine (L2), were synthesised using a solvent-free melt method. These ligands were then used to access three pairs of functionalised luminescent ReI complexes of the generic type fac-{Re(CO)3(diimine)(Ln)}(BF4). The photophysical studies show that the visible emission from each of the six complexes is 3MLCT at room temperature. Within each pair of complexes the precise energy of the emission was subtly dependent upon the axial ligand, Ln with luminescence lifetimes in the range 121–288 ns