ic8b02974_si_001.pdf (1.89 MB)
Supramolecular Construction of Cyanide-Bridged ReI Diimine Multichromophores
journal contribution
posted on 2019-01-11, 18:03 authored by Kristina S. Kisel, Alexei S. Melnikov, Elena V. Grachova, Antti J. Karttunen, Antonio Doménech-Carbó, Kirill Yu. Monakhov, Valentin G. Semenov, Sergey P. Tunik, Igor O. KoshevoyThe
reactions of labile [Re(diimine)(CO)3(H2O)]+ precursors (diimine = 2,2′-bipyridine, bpy; 1,10-phenanthroline,
phen) with dicyanoargentate anion produce the dirhenium cyanide-bridged
compounds [{Re(diimine)(CO)3}2CN)]+ (1 and 2). Substitution of the axial carbonyl
ligands in 2 for triphenylphosphine gives the derivative
[{Re(phen)(CO)2(PPh3)}2CN]+ (3), while the employment of a neutral metalloligand
[Au(PPh3)(CN)] affords heterobimetallic complex [{Re(phen)(CO)3}NCAu(PPh3)]+ (4). Furthermore,
the utilization of [Au(CN)2]−, [Pt(CN)4]2–, and [Fe(CN)6]4–/3– cyanometallates leads to the higher nuclearity aggregates [{Re(diimine)(CO)3NC}xM]m+ (M = Au, x = 2, 5 and 6; Pt, x = 4, 7 and 8;
Fe, x = 6, 9 and 10). All
novel compounds were characterized crystallographically. Assemblies 1–8 are phosphorescent both in solution
and in the solid state; according to the DFT analysis, the optical
properties are mainly associated with charge transfer from Re tricarbonyl
motif to the diimine fragment. The energy of this process can be substantially
modified by the properties of the ancillary ligands that allows to
attain near-IR emission for 3 (λem =
737 nm in CH2Cl2). The Re–FeII/III complexes 9 and 10 are not luminescent
but exhibit low energy absorptions, reaching 846 nm (10) due to ReI → FeIII transition.