Controlling conformations and physical properties of meso-tetrakis(phenylethynyl)porphyrins by ring fusion: synthesis, properties and structural characterizations.
The boron trifluoride-catalyzed Rothemund condensations of phenylpropargylaldehyde with 4,7-dihydro-4,7-ethano-2H-isoindole or 3,4-diethylpyrrole in dichloromethane at low temperature give 5,10,15,20-tetrakis(phenylethynyl)porphyrins bearing bicyclo[2.2.2]octadiene and octaethyl substituents, respectively. The former undergoes a retro Diels-Alder reaction to afford 5,10,15,20-tetrakis(phenylethynyl)benzoporphyrin quantitatively. The different conformations of the porphyrin periphery were determined by X-ray diffraction and their redox and spectroscopic properties have been investigated.
Shen
Zhen
Z
Department of Chemistry, Faculty of Science, Ehime University, Matsuyama, Japan.
Uno
Hidemitsu
H
Shimizu
Yusuke
Y
Ono
Noboru
N