Supramolecular Construction of Cyanide-Bridged Re<sup>I</sup> Diimine
Multichromophores
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. Koshevoy
10.1021/acs.inorgchem.8b02974.s001
https://acs.figshare.com/articles/journal_contribution/Supramolecular_Construction_of_Cyanide-Bridged_Re_sup_I_sup_Diimine_Multichromophores/7578716
The
reactions of labile [Re(diimine)(CO)<sub>3</sub>(H<sub>2</sub>O)]<sup>+</sup> precursors (diimine = 2,2′-bipyridine, bpy; 1,10-phenanthroline,
phen) with dicyanoargentate anion produce the dirhenium cyanide-bridged
compounds [{Re(diimine)(CO)<sub>3</sub>}<sub>2</sub>CN)]<sup>+</sup> (<b>1</b> and <b>2</b>). Substitution of the axial carbonyl
ligands in <b>2</b> for triphenylphosphine gives the derivative
[{Re(phen)(CO)<sub>2</sub>(PPh<sub>3</sub>)}<sub>2</sub>CN]<sup>+</sup> (<b>3</b>), while the employment of a neutral metalloligand
[Au(PPh<sub>3</sub>)(CN)] affords heterobimetallic complex [{Re(phen)(CO)<sub>3</sub>}NCAu(PPh<sub>3</sub>)]<sup>+</sup> (<b>4</b>). Furthermore,
the utilization of [Au(CN)<sub>2</sub>]<sup>−</sup>, [Pt(CN)<sub>4</sub>]<sup>2–</sup>, and [Fe(CN)<sub>6</sub>]<sup>4–/3–</sup> cyanometallates leads to the higher nuclearity aggregates [{Re(diimine)(CO)<sub>3</sub>NC}<sub><i>x</i></sub>M]<sup><i>m</i>+</sup> (M = Au, <i>x</i> = 2, <b>5</b> and <b>6</b>; Pt, <i>x</i> = 4, <b>7</b> and <b>8</b>;
Fe, <i>x</i> = 6, <b>9</b> and <b>10</b>). All
novel compounds were characterized crystallographically. Assemblies <b>1</b>–<b>8</b> 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 <b>3</b> (λ<sub>em</sub> =
737 nm in CH<sub>2</sub>Cl<sub>2</sub>). The Re–Fe<sup>II/III</sup> complexes <b>9</b> and <b>10</b> are not luminescent
but exhibit low energy absorptions, reaching 846 nm (<b>10</b>) due to Re<sup>I</sup> → Fe<sup>III</sup> transition.
2019-01-11 18:03:30
charge transfer
diimine fragment
Cyanide-Bridged Re
novel compounds
Diimine Multichromophores
CH 2 Cl 2
near-IR emission
energy absorptions
dicyanoargentate anion
NC
CN
737 nm
Supramolecular Construction
DFT analysis
x M
846 nm
Re tricarbonyl motif
III
II
carbonyl ligands