You are here: Home :: Area NEM :: Chemistry :: Inorganic chemistry

H. Bock, N. Nagel, P. Eller

1,1´,3,3´-Tetramethyl-2,2´-diimidazolium dication: Its bromide salt and the tetraphenylborates of its ketone adducts

The crystal structures of several 1,1´,3,3´-tetramethyl-2,2´-diimidazolium dication salts were determined at low temperatures. The dihedral angles between the planes of the two five-membered rings vary between 64° in the bromide salt and up to 80° in the ketone adduct tetraphenylborates, indicating some conformational flexibility around the central C–C bond of the 1,1´,3,3´-tetramethyl-2,2´-diimidazolium dication. Semiempirical calculations predict the conformation with a dihedral angle of 90° to be most favourable and the conformations within the crystal structures to be results of packing effects. In tetra phenyl borate salts of ketone and diketone adducts, the oxygen centers coordinate to the dication from above as well as below the defined molecular least squares plane and form chains of alternating dications and ketones. Since this packing motif is found in tetraphenylborate salts with different ketones, it might prove to be a robust supramolecular synthone in crystal engineering.

Zeitschrift für Kristallographie, Oldenbourg Wissenschaftsverlag

Print ISSN: 0044-2968
Volume: 215, 01/2000
Pages: 39

Journal homepage (external site)

Show all available items of this journal

 

Area NEM