Nierengarten Jean-François, Hahn Uwe, Trabolsi Ali, Herschbach Haiko, Cardinali François, Elhabiri Mourad, Leize Emmanuelle, Van Dorsselaer Alain, Albrecht-Gary Anne-Marie
Groupe de Chimie des Fullerènes et des Systèmes Conjugués, Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 4, France.
Chemistry. 2006 Apr 12;12(12):3365-73. doi: 10.1002/chem.200501238.
Dendritic branches with 1, 2, or 4 peripheral fullerene subunits and an ammonium function at the focal point have been prepared. Their ability to form self-assembled dendritic structures with oligophenylenevinylene receptors bearing one or two crown ether moieties has been evidenced by ES-MS studies for the first time. These supramolecular complexes are multicomponent photoactive devices in which the emission of the central receptor is dramatically quenched by the fullerene units. This new property resulting from the association of the different molecular subunits allowed detailed investigations of the self-assembly process by means of fluorescence titrations. The binding studies have revealed positive cooperative effects for the assembly of the fullerodendrimers with the ditopic receptor. Interestingly, the stability of the supramolecular 2:1 structures increases as the size of the dendritic unit increases. This positive dendritic effect has been explained by the larger number of possible intramolecular fullerene-fullerene interactions between the two dendritic guests when the number of fullerene subunits is increased.
已制备出在焦点处带有1个、2个或4个外围富勒烯亚基及铵官能团的树枝状分支。首次通过电喷雾质谱（ES-MS）研究证实了它们与带有一个或两个冠醚部分的寡聚亚苯基乙烯基受体形成自组装树枝状结构的能力。这些超分子复合物是多组分光活性器件，其中中心受体的发射被富勒烯单元显著淬灭。不同分子亚基缔合产生的这一新特性使得能够通过荧光滴定对自组装过程进行详细研究。结合研究揭示了富勒烯树枝状大分子与双位点受体组装时的正协同效应。有趣的是，超分子2:1结构的稳定性随着树枝状单元尺寸的增加而提高。当富勒烯亚基数量增加时，两个树枝状客体之间可能的分子内富勒烯-富勒烯相互作用数量增多，从而解释了这种正树枝状效应。
