On the "gluing" effect of lithium: the lithium-driven assembly of circum-arranged, edge-fused cyclopentadienyl lithium compounds and aza analogues.
Predictions (DFT/B3LYP calculations) are that cyclopentadienyl lithium edge-fused to [n]circulenes in a circum-like manner should self-assemble as rod-like, nanometer long, supersandwich compounds (see figure). On the contrary, triazolyl lithium analogues prefer to dimerize thereby giving rise to shell-like dimers of variable curvatures.This study is aimed at exploring M. Etter's (T. W. Panunto, Z. Urbanczyk-Lipkowska, R. Jonhson, M. Etter, J. Am. Chem. Soc. 1987, 109, 7786-7797) bottom-up approach towards the design of organic-solid sate materials. Guided by the electrostatic paste ("gluing") effect of lithium, we examined the self-assembly modes of a series of cyclopentadienyl lithium edge-fused to benzene, as well as to [n]circulenes, arranged in a circum-like manner by means of DFT/B3 LYP calculations. We have also examined the self-assembly modes of the analogous triazolyl derivatives. Generally, well defined trends have been found. Thus, whereas cylcopentadienyl derivatives 1, 3 and 5 tend to aggregate as rod-like, nanometer-long, supersandwich compounds, the corresponding triazolyl analogues 2, 4 and 6 tend to dimerize thus giving rise to shell-like dimers of variable curvatures. In our view, M. Etter's bottom-up approach combined with high level calculations appears to have great potential for designing complex molecular architectures and nanostructures. Hopefully, these studies will spur the activity of synthetic and materials chemists.
Saá
José M
JM
Departamento de Química, Universidad de las Islas Baleares, 07122 Palma de Mallorca, Spain. jmsaa@uib.es
Yañez
Manuel
M