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Phenylene-Bridged Expanded Porphyrazines
Fumiya Iizuka1, Yuto Kage2, Nagao Kobayashi1,3
1Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, 980-8578, Japan.
Abstract:
Novel expanded porphyrazines comprising o- and p-phenylene units were synthesized from self-condensation reactions of acyclic [2+1]-type precursors prepared from 1,3-diiminoisoindoline and the corresponding phenylenediamines. Möbius and Hückel topological structures of [4+2]-type and [3+2]-type expanded porphyrazines, respectively, were elucidated by X-ray crystallography. Despite the Möbius and Hückel [4n]π-electron systems, these expanded porphyrazines are virtually nonaromatic as a result of their flexible structures in solution, which may diminish intrinsic aromaticity and antiaromaticity.
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