title: Lanthanoid-based ionic liquids incorporating the dicyanonitrosomethanide anion.
abstract: A series of low-melting-point salts with hexakisdicyanonitrosomethanidolanthanoidate anions has been synthesised and characterised: (C(2) mim)(3) [Ln(dcnm)(6)] (1 Ln; 1 Ln=1 La, 1 Ce, 1 Pr, 1 Nd), (C(2) C(1) mim)(3) [Pr(dcnm)(6)] (2 Pr), (C(4) C(1) pyr)(3) [Ce(dcnm)(6)] (3 Ce), (N(1114))(3) [Ln(dcnm)(6)] (4 Ln; 4 Ln=4 La, 4 Ce, 4 Pr, 4 Nd, 4 Sm, 4 Gd), and (N(1112OH) )(3) [Ce(dcnm)(6)] (5 Ce) (C(2) mim=1-ethyl-3-methylimidazolium, C(2) C(1) mim=1-ethyl-2,3-dimethylimidazolium, C(4) C(1) py=N-butyl-4-methylpyridinium, N(1114) =butyltrimethylammonium, N(1112OH) =2-(hydroxyethyl)trimethylammonium=choline). X-ray crystallography was used to determine the structures of complexes 1 La, 2 Pr, and 5 Ce, all of which contain [Ln(dcnm)(6)](3-) ions. Complexes 1 Ln and 2 Pr were all ionic liquids (ILs), with complex 3 Ce melting at 38.1 °C, the lowest melting point of any known complex containing the [Ln(dcnm)(6)](3-) trianion. The ammonium-based cations proved to be less suitable for forming ILs, with complexes 4 Sm and 4 Gd being the only salts with the N(1114) cation to have melting points below 100 °C. The choline-containing complex 5 Ce did not melt up to 160 °C, with the increase in melting point possibly being due to extensive hydrogen bonding, which could be inferred from the crystal structure of the complex.
authors: School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
authors: Anthony S R
authors: AS
authors: Chesman
authors: Mei
authors: M
authors: Yang
authors: Nicolas D
authors: ND
authors: Spiccia
authors: Glen B
authors: GB
authors: Deacon
authors: Stuart R
authors: SR
authors: Batten
authors: Anja-Verena
authors: AV
authors: Mudring