CHIMIA 2014, Volume 68 ISSN 0009-4293 www. chimia.ch Supplementa to Issue 7-8/2014 SCS Fall Meeting 2014 Poster Abstracts Session of Computational Chemistry September 11, 2014 University of Zurich, Irchel Campus http://scg.ch/fallmeeting2014 Swiss Chemical Society Schwarztorstrasse 9 3007 Bern Switzerland
[email protected] www.scg.ch Computational Chemistry, Poster CC-101 Theoretical conformation analysis of a triazine-based, double decker rotor molecule with three anthracene blades Maike Bergeler1, Max Kory1, A. Dieter Schlüter1, Markus Reiher1 * 1ETH Zurich In this theoretical study we investigate the relative stability of a rotor-shaped molecule based on two triazine cores connected by three anthracene-derived blades, which is useful for polymerization, by Density Functional Theory. The structure has been synthesized on a gram scale from readily available building blocks by exploiting the selectivity difference for the nucleophilic substitution of cyanuric chloride [1]. Since the rotor-shaped molecule can flip its anthracene shovels to a conformation with two pi-stacked anthracene rings in which the cog wheel-like structure is no longer existent and the desired polymerization gets unfeasible, a detailed understanding of the reaction barrier between the rotor-shaped and the pi-stacked structures and an insight into the solvation effects on the relative stability of the two structures is neccessary to predict their occurence. Our theoretical analysis reveals a delicate balance between solvent-solute and solute-solute dispersion interactions that determine the relative stability of the two stable conformers. We found that in the gas phase the structure with pi- stacked anthracene rings is by 3 kcal/mol more stable than the rotor-shaped molecule, if we take dispersion interactions into account.