New classes of porphyrazine macrocycles with annulated heterocyclic rings

Abstract

<jats:p> The present contribution summarizes the most recent results on the synthesis and chemical physical characterization of the new classes of porphyrazine macrocycles having annulated five- and seven-membered heterocyclic rings, i.e. tetrakis(thiadizole)porphyrazine, TTDPzH <jats:sub>2</jats:sub>, tetrakis(selenodiazole)porphyrazine, TSeDPzH <jats:sub>2</jats:sub>, tetrakis-2,3-(5,7dipheny-6H-1,4-diazepino)porphyrazine, Ph <jats:sub>8</jats:sub> DzPzH <jats:sub>2</jats:sub>, and a number of their metal derivatives, prepared by using, respectively, 3,4-dicyano-1,2,5-thiadiazole, 3,4-dicyano-1,2,5-selenodiazole, and 5,7-diphenyl-2,3-dicyano-6H-1,4-diazepine as monomeric precursors. The available information indicates that, owing to the presence of electron rich and soft atoms ( S , Se ) inserted in the proximity of the porphyrazine core, the TTDPz and TSeDPz macrocycles, closely resembling their phthalocyanine analogues in terms of structural and electronic features and physical behaviour (solubility, thermal stability, vaporizability, etc.), might be promising new materials for applicative properties. Particularly interesting is the operated peripheral ring opening of the TSeDPz macroxycle leading to the formation of octaaminoporphyrazine, followed by its conversion to a tetrakis(pyrazino)porphyrazine. The macrocycles containing the Ph <jats:sub>8</jats:sub> DzPz skeleton, due to the presence of the external non planar diphenyldiazepine units, appear to exhibit a distinct physical behaviour, which can be probably modulated by appropriate alternative substitutions in the 5, 6, and 7 positions of the diazepine rings. </jats:p>

Dedication to Professor Claudio Ercolani on the Occasion of his 75th Birthday

“…Professor Ercolani has published more than 120 scientific works including 8 book chapters and review articles. [1][2][3][4][5][6][7][8] Among other research items, he has developed especially intense and successful scientific activity and published 90 research articles in the field of tetrapyrrolic macrocycles, devoting his attention to: 1) Synthesis and characterization of new monophthalocyanine complexes. [9][10][11][12][13][14] 2) Interaction of metal phthalocyanines with small molecules (NO, CO, O 2 ) and N-bases.…”

Application of phthalocyanines in flow- and sequential-injection analysis and microfluidics systems: A review

“…A π deficiency due to the presence of a thiodiazole, instead of benzene ring of the phthalocyanine unit, results in a blue shifting of the Q band. The lowering of the highest occupied molecular orbital (HOMO) is larger than that of the lowest unoccupied molecular orbital (LUMO), resulting in a larger HOMO-LUMO gap [50].…”

Synthesis and Photophysical, Electrochemical and Theoretical Study of Thi­azole‐Annelated Phthalocyanines

“…[8] Heterocyclic annelation to the phthalocyanine skeleton also results in an improvement in the thermic, chemical, and photochemical stability of the macrocycle. [9] Another aspect is the modification of the Pc unit caused by the electron- donating and/or electron-withdrawing effects of the heterocycle.…”