Electrosynthesis of Phthalocyanines:  Influence of Solvent

Abstract

Several methods for the synthesis of metal-free phthalocyanine (Pc or PcH2) and copper phthalocyanine (PcCu) from urea and phthalic anhydride, phthalimide, 1,3-diiminoisoindoline (1,3-D), and phthalonitrile have been studied. The results show that the nature of the solvent is the most important factor in the conventional chemical and direct electrochemical synthesis of the final products. Different routes for phthalocyanine preparation are discussed.

A simple synthesis of symmetric phthalocyanines and their respective perfluoro and transition‐metal complexes

“…Pcs can be made by the cyclisation of phthalonitriles in the presence of an organic base . However, all these procedures include cumbersome and/or difficult synthesis or separation steps.…”

Use of elemental metals in different grade of activation for phthalocyanine preparation

“…Various routes can yield PcH 2 or PcM at low temperature (0-60°C) from phthalonitrile, in particular the direct electrochemical procedure with use of sacrificial metal anodes or metal salts [1][2][3], use of solid strong bases [4], and by UV-irradiation of the reaction system [5]. The recent article [6] should be especially mentioned, in which softest conditions for Pc obtaining were offered.…”

“…At present, in order to optimize the low-temperature preparation of phthalocyanines, five routes are being developed in our laboratory: (1) UV-irradiation of the reaction system (without metals use) [1]; (2) use of elemental metals in the form of finely divided metal powders and Rieke metals as ''matrices'' for phthalonitrile 1387 cyclization and Pc core formation; (3) direct electrochemical synthesis using sacrificial anodes and even cathodes; (4) use of zeolites and other microporous materials (without metals use), and (5) use of so-called ''supported metals'' [7]. In this work, we present the experimental results of the second technique.…”

Microwave-assisted synthesis and characterization of novel symmetrical substituted 19-membered tetrathiadiaza metal-free and metallophthalocyanines and investigation of their biological activities

“…Generally, phthalocyanines can be obtained by the template reactions of diverse precursors such as phthalonitrile, cyano-benzamide, phthalic acid and phthalamide with metal salts in highboiling nonaqeous solvents at elevated temperatures [16,17].…”