Feng Lai, Wakahara Takatsugu, Nakahodo Tsukasa, Tsuchiya Takahiro, Piao Qiuyue, Maeda Yutaka, Lian Yongfu, Akasaka Takeshi, Horn Ernst, Yoza Kenji, Kato Tatsuhisa, Mizorogi Naomi, Nagase Shigeru
Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.
Chemistry. 2006 Jul 17;12(21):5578-86. doi: 10.1002/chem.200501545.
The reaction of La@C82 with diethyl bromomalonate in the presence of base (the Bingel reaction) generated five monoadducts which have been fully characterized. It was found that four of them (mono-A, -B, -C, and -D) are ESR-inactive, suggesting singly bonded regioisomers. In contrast, the fifth product (mono-E) is ESR-active, indicating that it possesses a cyclic moiety between the appended malonate group and the fullerene cage, analogous to conventional Bingel adducts. The differences in the molecular structures of mono-A, -B, -C, and -E result in varying thermal stabilities and electrochemical behavior. In particular, the singly bonded monoadducts undergo the retro-Bingel reaction either under thermal treatment or during electron transfer on the cyclic voltammetric timescale. However, mono-E shows remarkable thermal stability and perfect reversibility under the same experimental conditions.
在碱存在的情况下，La@C82与溴代丙二酸二乙酯发生反应（宾格尔反应），生成了五个单加合物，且这些单加合物均已得到充分表征。结果发现，其中四个（单加合物A、B、C和D）无电子自旋共振活性，表明它们是单键区域异构体。相比之下，第五个产物（单加合物E）具有电子自旋共振活性，这表明它在连接的丙二酸酯基团和富勒烯笼之间存在一个环状部分，类似于传统的宾格尔加合物。单加合物A、B、C和E的分子结构差异导致了热稳定性和电化学行为的不同。特别是，单键单加合物在热处理或循环伏安时间尺度上的电子转移过程中会发生逆宾格尔反应。然而，在相同的实验条件下，单加合物E表现出显著的热稳定性和完美的可逆性。
