Synthesis and physical properties of tris(dialkylamino)cyclopropenium dicyanamide ionic liquids.

The synthesis and properties of 16 tris(dialkylamino)cyclopropenium (TDAC) cations with the dicyanamide (DCA) anion, [N(CN)], are described. - and -symmetric cations ([C(NR)]DCA (R = Me, Et, Pr, Bu, Pent, Hex, Dec) and [C(NRMe)]DCA (R = Bu, St), respectively) were synthesised by reaction of CClH with the corresponding amine. Reaction of the alkoxydiaminocyclopropenium salt [C(NEt)(OMe)] with amines led to a series of -symmetric salts [C(NEt)(NR)]DCA (R = Me, Bu, Hex) and two -symmetric salts and [C(NEt)(NRMe)]DCA (R = Me, Bu). Similarly, [C(NMe)(OMe)], was used to prepare the -symmetric salts [C(NMe)(NRMe)]DCA (R = Pr, Bu). In addition to characterisation by NMR, mass spectrometry and microanalysis, the salts were characterised by DSC, TGA, density, viscosity, conductivity and miscibility/solubility studies. Comparisons have been made with similar series of bistriflimide (NTf ) salts that have been previously reported to see whether the same trends are observed with a different anion.