Sawhorse‐Type Tetracarbonyldiruthenium Tweezers

Abstract

Molecular tweezers built from sawhorse-type dinuclear ruthenium units and carboxyphenyl porphyrin derivatives {5-(4-carboxyphenyl)-10,15,20-triphenyl-21H,23H-porphyrin, [5-(4-carboxyphenyl)-10,15,20-triphenylporphyrin]zinc, 5,10-bis(4-carboxyphenyl)-15,20-diphenyl-21H,23H-porphyrin, and [5,10-bis(4-carboxyphenyl)-15,20-diphenylporphyrin]zinc} are presented. Molecular modeling shows that in all cases the two porphyrin moieties are adequately positioned to encapsulate guest molecules. Therefore, the [a] Institute

Heterocomponent ternary supramolecular complexes of porphyrins: A review

“…Two guests are subsequently attracted to this receptor due to the dual binding character of this bis-porphyrin: the anion binding the diindol subunit and the diamine binding two Zn-porphyrin moieties. The complexation with DABCO induces the diindol conformational change to its s-cis-configuration, and this creates a well-defined binding pocket for the [39] with permission from The Royal Society of Chemistry) and sawhorse type tweezers (c) [40] anion. Binding of either guest, chloride or DABCO to the starting host induces the formation of a molecular tweezer and therefore facilitates the second guest binding (Fig.…”

“…Therrien and Armaroli demonstrated an alternative strategy for noncovalent coupling of porphyrin units [40].…”

“…5c). The sawhorse tweezers are connected through single or double dinuclear ruthenium complexes and can bind pyridinegroup-bearing guests such as pyridine, 4,4′-bipyridine, 1,2-bis(4-pyridyl)ethylene and also (4-pyridyl)-substituted porphyrins to Zn-porphyrin units with association constant of up to 4.0 × 10 7 M -1 in toluene [40].…”