A star‐shaped hexaquinocyclohexane molecule 4 c is reported, which turns out to be a closed‐shell extended [6]radialene with a twisted‐boat conformation according to X‐ray crystallographic analysis. It was formed by an unusually slow decay of its in situ generated open‐shell valence isomer, the hexa‐radicaloid 4 o, with a half‐life time of about 156 min at room temperature. Reaction progress kinetic analysis revealed a large energy barrier of about 95.5±4.3 kJ mol⁻¹ at room temperature from the hexa‐radical form 4 o to the contorted [6]radialene form 4 c, because the transformation needs to overcome large steric repulsion between the neighboring phenoxyl units. Compound 4 c can be chemically reduced to radical anion and dianion, and the dianion is actually a diradical dianion, with a calculated diradical character of 71.9 %. This study demonstrates the unique chemical bonding nature of contorted quinoidal π‐conjugated molecules and a very unusual valence isomerization process.

中文翻译：

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六（3,6-二叔丁基-4-氧代-2-2,5-环己二烯-1-亚基）环己烷：闭壳[6]芳烃或开壳六聚放射性大分子？

据报道，有一个星形的六喹啉环己烷分子4 c，根据X射线晶体学分析，它是具有扭曲的船形构型的闭壳扩展[6]芳烃。它是由它的原位产生的开壳层价异构体，六- radicaloid的异常缓慢衰变形成4 O，在室温下用约156分钟的半衰期的时间。反应进程动力学分析表明，在室温下，从六价自由基形式4 o到扭曲的[6]芳烃形式4 c约有95.5±4.3 kJ mol ^-1的大能垒，这是因为该转变需要克服两者之间的大空间排斥作用相邻的苯氧基单元。化合物 4 c可以被化学还原成自由基阴离子和二价阴离子，该二价阴离子实际上是双价双价阴离子，计算出的双价基特征为71.9％。这项研究证明了扭曲的quinoidalπ共轭分子的独特化学键合性质以及非常不寻常的化合价异构化过程。