Phthalocyanines of a novel structure: Dinaphthotetraazaporphyrins with D[sub 2h] symmetry

Journal Article · Wed Apr 27 00:00:00 EDT 1994 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00087a003· OSTI ID:6922437

Kobayashi, Nagao; Ashida, Tohru; Osa, Tetsuo ^[1]; Konami, Hideo

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1. Tohoku Univ., Aobayama, Aoba, Sedai (Japan) Tohoku Univ., Kathahira, Sendai (Japan)

Phthalocyanines (Pcs) are compounds in which a benzene ring is fused to each of the four pyrrole rings of tetraazaporphyrins (TAPs). In addition to traditional uses as dyes and in xerography, they are now rapidly increasing in importance in many fields such as batteries, photodynamic cancer therapy, chemical sensors, molecular metals, and liquid crystals. Two naphthalene molecule-fused tetraazaporphyrins (TAPs) with D[sub 2h] symmetry have been synthesized, and some of their spectroscopic and electrochemical properties are reported. These compounds are structural isomers of phthalocyanines (Pcs) in the sense that four benzene units are fused to the TAP skeleton. In contrast to MPcs (M = metal) with D[sub 4h] symmetry, both the Q[sub o-o] and Soret bands split into two as a result of the lowering of the molecular symmetry. Magnetic circular dichroism (MCD) shows Faraday B terms corresponding to the peaks and shoulders of the electronic absorption spectra, indicating that no degenerate state is included. The fluorescence quantum yield of the zinc complex is much smaller than in ZnPc with D[sub 4h] symmetry. The electronic absorption and electrochemical redox data of these complexes are reproduced by molecular orbital (MO) calculations within the framework of the Pariser-Parr-Pople (PPP) approximation. The results are compared with those of Pcs and mononaphtho-TAPs.

• OSTI ID: 6922437
• Journal Information: Inorganic Chemistry; (United States), Vol. 33:9; ISSN 0020-1669
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
25 ENERGY STORAGE
PHTHALOCYANINES
ABSORPTION SPECTROSCOPY
ELECTROCHEMISTRY
CHEMICAL PREPARATION
MOLECULAR ORBITAL METHOD
MOLECULAR STRUCTURE
SYMMETRY
CALCULATION METHODS
CHEMISTRY
DYES
HETEROCYCLIC COMPOUNDS
ORGANIC COMPOUNDS
SPECTROSCOPY
SYNTHESIS
400500* - Photochemistry
400400 - Electrochemistry
250903 - Energy Storage- Batteries- Materials
Components
& Auxiliaries