Sawhorse-Type Tetracarbonyldiruthenium Tweezers

Molecular tweezers built from sawhorse-type dinuclearruthenium 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 hostguest interactions between the sawhorse-type tetracarbonyldiruthenium tweezers and different guest molecules [fullerene (C60), pyridine (pyr), 4,4'-bipyridine (bpy), 1,2-bis(4-pyridyl)ethylene (bpe), 5,10-bis(4-pyridyl)-15,20-diphenyl-21H,23H-porphyrin (5,10-dpp), and 5,15-bis(4-pyridyl)-10,20-diphenyl-21H,23H-porphyrin (5,15-dpp)] have been studied in solution by using optical spectroscopic methods.