Synthesis, Optical Properties, Structures and Molecular Orbital Calculations of Subazaporphyrins, Subphthalocyanines, Subnaphthalocyanines and Related Compounds

Abstract

<jats:p> The synthesis of and spectroscopic data on subazaporphyrins, subphthalocyanines, subnaphthalocyanines and their related compounds reported to date are summarized, together with the results of molecular orbital (MO) calculations from our laboratory. Thus the problems and key points in the synthesis of these subazamacrocycles and their electronic absorption and magnetic circular dichroism (MCD) spectra are discussed, together with those of the monosubstituted-type low-symmetrical phthalocyanines obtained by their ring expansion reaction. The Q bands of these subazamacrocycles are orbitally doubly degenerate, and in the Soret band region, three transitions to the orbitally degenerate state are found. The MO calculations suggest that the HOMO levels destabilize considerably while the LUMO levels change slightly with increasing size of the π system. In addition, the electronic adsorption data are reproduced by the calculation only when the two pyrrole hydrogens in the monosubstituted-type phthalocyanines are assumed to be linked to the two pyrrole nitrogens along the short axis. </jats:p>

Synthesis of Aza-, Oxa-, and Thiaporphyrins and Related Compounds

“…The chemistries of subphthalocyanines and subtriazaporphyrins (subporphyrazines) have been reviewed in detail by research groups of Torres 241 and Kobayashi. 242 In this section, we have focused exclusively on the synthesis and selected properties of several subporphyrazines. In 2005, Torres and co-workers reported the development of a boron-templated cyclization method for the synthesis of subporphyrazines.…”