Conjugated di- and trinuclear phthalocyanines and their analogs

Abstract

Extended π-electron delocalization is the most important property of phthalocyanines and structurally related systems. The position of the longest wavelength absorption (Q-band) is influenced by the kind of substituents and by additional fused benzene rings at the ligand. Very large wavelength shifts are obtained with planar annulated di- and trinuclear phthalocyanine analogs sharing a common benzene ring which are the main point of this review. In addition, condensed di- and trinuclear phthalocyanines, and di- and trinuclear phthalocyanines linked via one or two carbon atoms of the macrocycles are discussed for comparison.