Luminescent Heterometallic Branched Alkynyl Complexes of Rhenium(I)−Palladium(II): Potential Building Blocks for Heterometallic Metallodendrimers

The photophysical and electrochemical behavior of a novel series of luminescent rhenium(I) complexes bearing a trialkynyl ligand, [1,3-(HC⋮C) 2 -5-{(N ∧ N)(CO) 3 ReC⋮C}C 6 H 3 ] (N ∧ N = t Bu 2 bpy 1, Me 2 bpy 2, bpy 3 ), and their heterometallic branched complexes, [1,3-{Cl(PEt 3 ) 2 PdC⋮C} 2 -5-{(N ∧ N)(CO) 3 ReC⋮C}C 6 H 3 ] (N ∧ N = Me 2 bpy 4, bpy 5 ), have been studied; the X-ray crystal structures of 2 and 5 have been determined. Density functional theory calculations have also been carried out in order to probe the bonding in these compounds.