顺磁性内嵌金属富勒烯La@C82的自由基偶联反应

Radical coupling reaction of paramagnetic endohedral metallofullerene La@C82.

作者信息

Takano Yuta, Yomogida Akinori, Nikawa Hidefumi, Yamada Michio, Wakahara Takatsugu, Tsuchiya Takahiro, Ishitsuka Midori O, Maeda Yutaka, Akasaka Takeshi, Kato Tatsuhisa, Slanina Zdenek, Mizorogi Naomi, Nagase Shigeru

机构信息

Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.

出版信息

J Am Chem Soc. 2008 Dec 3;130(48):16224-30. doi: 10.1021/ja802748q.

DOI:10.1021/ja802748q

PMID:18998645

Abstract

The thermal reaction of La@C(82)(C(2v)) with 3-triphenylmethyl-5-oxazolidinone (1) in toluene affords benzyl monoadducts La@C(82)(C(2v))(CH(2)C(6)H(5)) (2a-2d). The same monoadducts are also obtained by the photoirradiation of La@C(82)(C(2v)) in toluene without the existence of 1. These reactions are applicable to paramagnetic metallofullerenes, such as La@C(82)(C(s)) and Ce@C(82)(C(2v)). The photoirradiation of La@C(82)(C(2v)) in 1,2-dichlorobenzene in the presence of alpha,alpha,2,4-tetrachlorotoluene also affords the monoadducts La@C(82)(C(2v))(CHClC(6)H(3)Cl(2)) (3a-3d). The monoadducts are fully characterized by spectroscopic analyses. Single-crystal X-ray structure analysis for 3d reveals the unique structure. Theoretical calculations show that the cage carbons having high spin densities are selectively attacked by radical species to form the monoadducts linked by a carbon-carbon single bond. The thermal reaction of La@C(82)(C(2v)) with 1 in benzene affords metallofulleropyrrolidine La@C(82)(C(2v))(C(2)H(4)NCPh(3)) (5), unlike the reaction in toluene.

摘要

La@C(82)(C(2v))与3-三苯基甲基-5-恶唑烷酮（1）在甲苯中发生热反应，生成苄基单加成产物La@C(82)(C(2v))(CH(2)C(6)H(5))（2a - 2d）。在不存在1的情况下，通过对甲苯中的La@C(82)(C(2v))进行光照射也可得到相同的单加成产物。这些反应适用于顺磁性金属富勒烯，如La@C(82)(C(s))和Ce@C(82)(C(2v))。在α,α,2,4-四氯甲苯存在下，对1,2-二氯苯中的La@C(82)(C(2v))进行光照射，也可得到单加成产物La@C(82)(C(2v))(CHClC(6)H(3)Cl(2))（3a - 3d）。通过光谱分析对单加成产物进行了全面表征。对3d的单晶X射线结构分析揭示了其独特结构。理论计算表明，具有高自旋密度的笼状碳被自由基物种选择性攻击，形成通过碳 - 碳单键连接的单加成产物。与在甲苯中的反应不同，La@C(82)(C(2v))与1在苯中发生热反应生成金属富勒吡咯烷La@C(82)(C(2v))(C(2)H(4)NCPh(3))（5）。