Thiele (Th) and tetrabenzo-Chichibabin (TBC) derivatives with terminal dibenzocycloheptatriene (DBHept) units were prepared. A clear correlation between their electronic and molecular structures was stablished. Insights into their closed- or open-shell ground states were gained, where particular contribution of the heptagonal carbocycles as end-groups was proved. Remarkably, a thermally accessible triplet diradical configuration was confirmed for the DBHept-TBC compound.

中文翻译：

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作为Thiele和四苯并-Chichibabin烃的端基的二苯并环庚三烯。

制备了带有末端二苯并环庚三烯（DBHept）单元的Thiele（Th）和四苯并-Chichibabin（TBC）衍生物。他们的电子和分子结构之间建立了明确的联系。获得了对它们的封闭或开放壳基态的洞察力，其中证明了七边形碳环化合物作为端基的特殊贡献。显着地，证实了DBHept-TBC化合物的热可接近三重双自由基结构。