Synthesis, Structures, and Properties of Polybenzo[n]spirenes with Carbon-Based Polyspiroconjugation
Kumpei Hasebe1, Kenichiro Itami2,3,4, Hideto Ito1
1Department of Chemistry, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
Abstract:
One-dimensional (1D) carbon-based polyspiroconjugated molecules, polybenzo[n]spirenes (n = 1-4), were synthesized using a simple and iterative synthetic protocol starting from anthraquinone. Polybenzo[n]spirenes possess one-dimensionally connected polyspirene cores with structures slightly distorted owing to peripheral benzo fusions. Because of the compact spiro-carbon centers, the surrounding p orbitals are orthogonal yet overlap significantly, enabling effective 1D-aligned polyspiroconjugation. As a result, the polybenzo[n]spirenes exhibited LUMO splitting and red-shifted absorption and emission as the number of spiro structures increased.
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