1710 - 1750 Makoto Fujita

EmergentSelf-assembly of Molecular Spheres

Self-assembly is a powerful technique for the bottom-up construction of discrete, well-defined nano-scale structures.^1,2   Large (> 50) multi-component systems offer mechanistic insights into biological assembly but are daunting synthetic challenges.   Here, we report the self-assembly of giant, M₂₄L₄₈ coordination spheres from 24 palladium ions (M) and 48 curved bridging ligands (L).³   The structure of this multi-component system is highly sensitive to the geometry of the bent ligands.   Even a slight change in the ligand bend angle critically switches the final structure observed across the entire ensemble of building blocks between M₂₄L₄₈ and M₁₂L₂₄ coordination spheres.   The amplification of a small initial difference into an incommensurable difference in the resultant structures is a key mark of emergent behavior. Functionalization at the periphery and the interior of the giant spheres will be also discussed.⁴ 

References

(1)  S. Sato, J. Iida, K. Suzuki, M. Kawano, T. Ozeki, and M. Fujita, Science 2006, 313, 1273-1276

(2)   K. Suzuki, S. Sato, and M. Fujita, Nature Chem. 2010,.2, 25

(3)   Q.-F. Sun, J. Iwasa, D. Ogawa, Y. Ishido, S. Sato, T. Ozeki, Y. Sei, K. Yamaguchi, and M. Fujita, Science 2010, in press. 

(4)  M. Ikemi, T. Kikuchi, S. Matsumura, K. Shiba, S. Sato,  and M. Fujita, Chem. Sci., 2010, in press.