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Synthesis of a Tetrabenzotetraaza[8]circulene by a “Fold‐In” Oxidative Fusion Reaction
Author(s) -
Chen Fengkun,
Hong Yong Seok,
Shimizu Soji,
Kim Dongho,
Tanaka Takayuki,
Osuka Atsuhiro
Publication year - 2015
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.201505124
Subject(s) - cyclooctatetraene , chemistry , crystallography , fusion , fluorescence , quantum yield , oxidative phosphorylation , photochemistry , stereochemistry , molecule , organic chemistry , physics , linguistics , philosophy , quantum mechanics , biochemistry
Tetrabenzotetraaza[8]circulene ( 1 ) has been synthesized in good yield by a “fold‐in” oxidative fusion reaction of a 1,2‐phenylene‐bridged cyclic tetrapyrrole. X‐ray diffraction analysis of 1 has revealed a planar square structure with a central cyclooctatetraene (COT) core that shows little alternation of the bond lengths. Despite these structural features, 1 shows aromatic‐like character, such as sharp absorption bands, high fluorescence quantum yields ( Φ F =0.55 in THF), and a single exponential fluorescence decay with τ F =3.8 ns. These observations indicate a dominant contribution of an [8]radialene‐like π conjugation and hence aromatic character of the local aromatic segments in 1 .