利用原位变温EPR研究富勒烯双体笼间的弱C―C键（英文）

A Weak Intercage C―C Bond in a [C_(60)]fullerene Dimer Studied by In situ Variable Temperature EPR Spectroscopy

本文研究了(C_(60))_2-[P(O)(OCH_3)]_2富勒烯双体内的笼间C―C键的热力学性质(该双体的结构详见文献,Chem.Commun.2011,47,6111)。原位、变温电子顺磁共振波谱实验结果表明,该C―C键的键离解能(BDE)为72.4 k J?mol^(-1)(17.3 kcal?mol^(-1)),仅约为常见氢键的两倍,或约为常见有机C―C键的五分之一。因此,该二聚体于较高温度时容易发生均裂反应,形成单体自由基;降温时又容易发生自由基聚合反应。基于该笼间C―C键所具有的这些热力学特性,我们对其可被用于制备有序的富勒烯分子元器件等材料作展开讨论。

This work studied the thermodynamic properties of a single intercage C--C bond in a [C60]fullerene dimer, （C60）2-[P（O）（OCH3）]2, previously synthesized by Wang et aL （Chem. Commun. 2011, 47, 6111）. Data obtained from in situ variable temperature electron paramagnetic resonance （EPR） indicated a relatively low bond dissociation enthalpy （BDE） for this bond of 72.4 kJ · mol^ -1 （17.3 kcal· mol^ -1）. This value is only approximately twice that of a typical hydrogen bond, or one fifth of the values determined for bonds in diamond or saturated hydrocarbons. The application of this pre-synthesized dimer to the formation of aligned fullerenes is discussed.