Synthesis of Functional Organometallic Complexes Involving a Pentahaptofullerene Ligand

五苯基富勒烯阴离子C_&lt；60&gt；Ph_5-由有机铜试剂五次加成而成，其金属络合物代表了一类新的环戊二烯衍生物，可通过母体化合物去质子化得到。在C&lt；60&gt；中的十二个五边形中，有一个是由C_&lt；60&gt；分子中剩余的50个sp2碳原子通过周围的5个SP3碳原子分离出来的，每个SP3碳原子都带有一个苯基。以往的X射线结晶学研究揭示了由五个苯基围绕环戊二烯基(CP)形成的高度独特的空穴结构，但未能提供这些独特分子的电子性质的信息。在这个研究项目中，我们进行了从头算分子轨道计算和电化学实验，得到了C&lt；60&gt；Ph_5-和C_&lt；60&gt；Ph_5H；C_&lt；60&gt；Ph_5H；与有机铜试剂反应生成三加成产物[C_&lt；70&gt；]的证据。Ar_3H，Ar=4-Cf_3-C_6H_4]。用金属醇盐去质子化三加成物形成相应的金属络合物C_&lt；70&Gt；Ar_3M[M=K，Tl]。从头算分子轨道计算和X-射线衍射研究结果表明，C&lt；70&gt；Ar3-在C&lt；7O&gt；Ar3M中是以eta^5-吲哚配位，而不是以eta^3-配位。

The pentaphenylated fullerene anion C_<60>Ph_5-, which is obtained through the five-fold addition of an organocopper reagent to C_<60>, and its metal complexes represent a new class of cyclopentadiene derivatives, which can be prepared through deprotonation of the parent compond. One out of twelve pentagons in C_<60> is isolated from the remaining 50 sp^2 carbon atoms of the C_<60> molecule by five surrounding sp3 carbon atoms each bearing a phenyl group. The previous X-ray crystallographic studies revealed the highly unique cavity structure formed around the cyclopentadienyl (Cp) moiety by the five phenyl groups, but failed to give us information on the electronic properties of these unique molecules. In this research project, we have carried out ab-initio molecular orbital calculations and electrochemical experiments and obtained evidence that there is endohedral homoconjugation, that is, an electronic interaction between the upper Cp and the lower C_<50> moiety in C_<60>Ph_5-and C_<60>Ph_5H through inside of the C_<60> cage.We also found that the reaction of C_<70> with an organ ocopper reagent gives a trisaddition product [C_<7O>Ar_3H, Ar = 4-CF_3-C_6H_4] with an indene-like substructure flanked by the three sp^3 carbons in a quantitative yield. The trisadduct was deprotonated with metal alkoxides to form the corresponding metal complexes C_<70>Ar_3M [M=K, Tl]. The results of ab initio molecular orbital calculations and X-ray diffraction study suggested that C_<70>Ar_3- coordinates to the metal as an eta^5-indenylide rather than a eta^3-ligand in C_<7O>Ar_3M.