Perspectives in the selective synthesis of phthalocyanines and related compounds

Abstract

<jats:p> The main aim of this paper is to describe the state of the art and the key problems of the selective synthesis of phthalocyanines and related compounds. This non-exhaustive overview comments on the synthesis of isomerically pure, unsymmetrically substituted and non-centrosymmetric phthalocyanines as well as intrinsically unsymmetric phthalocyanine-related compounds. </jats:p>

Synthesis and electrochemical and spectroelectrochemical characterization of chloromanganese(III) phthalocyanines

“…Due to the presence of single substituents on each phthalonitrile precursor, the Pcs were isolated as a mixture of isomers as expected for tetra-substituted Pcs. 26,27 No attempt was made to separate the isomers of the complexes.…”

Isomeric separation and identification of tetra-, tri-, and di-β-sulphonic phthalocyanine zinc complexes

“…For the cyclotetramerization reaction of 4-substituted phthalyl derivatives, which leads to β-substituted PCs, statistical distribution is always observed [30]. Whatever the reaction conditions are, neither steric effects of the substituents nor electric ones are able to act as driving forces for regioselective ring closure [31]. Thus, based on statistical distribution, the isomer distribution ratios of each group of sulphonic PCs are predicted and listed in Table 1.…”

Tetrapyrazinoporphyrazines and their metal derivatives. Part I: Synthesis and basic structural information

“…These substituents have usually a key role either in the mechanism of the action in selected applications [59,132,164] or they are used for further functionalization [56,57,156,167,168,239]. The synthesis of low-symmetry TPyzPzs requires alternative approaches and many of them have been extensively reviewed for Pc analogs [240][241][242]. Reports on synthetic methods for low-symmetry TPyzPz are aimed almost exclusively on statistical condensation (also known as mixed cyclotetramerization) of two dinitrile precursors A and B.…”