화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.128, No.34, 11150-11159, 2006
Cyclization and catenation directed by molecular self-assembly
We report here that molecular self-assembly can effectively direct and enhance specific reaction pathways. Using perylene pi-pi stacking weak attractive forces, we succeeded in synthesizing perylene bisimide macrocyclic dimer and a concatenated dimer-dimer ring from dynamic self-assembly of monomeric bis-N,N'-( 2-( 2-( 2-( 2-thioacetylethoxy) ethoxy) ethoxy) ethyl) perylenetetracarboxylic diimide. The monocyclic ring closure and the dimer-dimer ring concatenation were accomplished through formation of disulfide bonds, which was readily triggered by air oxidization under basic deacetylation conditions. The perylene cyclic dimer and its concatenated tetramer were characterized using both structural methods (NMR, mass spectroscopy) and photophysical measurements (UV-vis spectroscopy). Kinetic analyses offer informative insights about reaction pathways and possible mechanisms, which lead to the formation of complex concatenated rings. Molecular dynamic behaviors of both the monocyclic dimer and the concatenated dime-dimer ring were modeled with the NWChem molecular dynamics software module, which shows distinct stacking activities for the monocyclic dimer and the concatenated tetramer.