Crystal Structure of Hexamethylguanidinium Hexafluorosilicate Hexahydrate

Single crystals of the hexamethylguanidinium hexafluorosilicate hexahydrate salt, C(NMe2)32(+)SiF6(2-)(dot) 6H2O, were isolated when a product, obtained by water removal from aqueous C(NMe2)3F in a glass vessel, was recrystallized from CH3OH. The crystal structure of this salt was determined, and the structure of the free hexamethylguanidinium cation was calculated, showing that the propeller-shaped structure of the hexamethylguanidinium cation is not caused by solid state effects but is the true minimum energy structure.
Prepared in cooperation with Loker Hydrocarbon Research Institute, University of Southern California, Los Angeles, CA.