Ionic Liquids Based on Hexachloridometalate(V) Anions (Sb, Nb and Ta) and Nitrile-functionalized Pyridinium Cations

Abstract

Single crystals of 1-(cyanoethyl)-3-methyl-pyridin-1-ium hexachloridoantimonate(V) (1), 1- (cyanomethyl)-3-methyl-pyridin-1-ium hexachloridoniobate(V) (2), 1-(cyanomethyl)-3-methylpyridin- 1-ium hexachloridotantalate(V) (3), 1-(cyanopropyl)-3-methyl-pyridin-1-ium hexachloridoniobate( V) (4), and 1-(cyanopropyl)-3-methyl-pyridin-1-ium hexachloridotantalate(V) (5) have been synthesized and characterized by X-ray diffraction. Compounds 1-3 crystallize in the triclinic space group P1̄ with Z = 2, and compounds 4 and 5 in the monoclinic space group C2/c with Z = 8. FTRaman spectra have been recorded and interpreted, especially with respect to the anions [MCl6]-. In addition, NMR spectra, a study of the melting behavior and elemental analyses complete the characterization.