π-Extended and strongly coupled chromophores are constantly explored because of their
potential for finding a place in many fields of research focusing on both aspects
– the fundamental knowledge and the application studies. The synthetic approach leading
to controlled formation of porphyrinoid system with two coordination cores shows an
alternative way for controlling the delocalization within the extended π-system. It
drastically influences the optic response which after a basic initiator (reversibly)
shifts the absorbance to the red region following the significant planarization that
increases observed communication between two subunits. Even deeper modification can
be done within the system by doping the obtained structure with boron(III) that in
addition introduces another switching factor based on Lewis acidity of the introduced
metalloid.
Key words
aromaticity - boron - porphyrinoids - triphyrins - π-delocalization - polycyclic aromatic
hydrocarbons (PAHs)