Tailored Palladate Tunable Aryl Alkyl Ionic Liquids (TAAILs)

Abstract

We present a new class of tunable aryl alkyl ionic liquids (TAAILs) containing different palladate counter ions. Solid‐state structures for representative compounds have been obtained. Their properties are presented in comparison to those of newly synthesized and reported palladate ionic liquids with conventional counter ions. It was found that the aryl substitution pattern and the type of anion have a profound influence on the melting point. The speciation of the different anions in solution has been rationalized by DFT calculations.

Palladium Complexes with Phenoxy- and Amidate-Functionalized N-Heterocyclic Carbene Ligands Based on 3-Phenylimidazo[1,5-a]pyridine: Synthesis and Catalytic Application in Mizoroki–Heck Coupling Reactions with Ortho-Substituted Aryl Chlorides

“…The use of ionic liquids as solvents in Pd-catalyzed cross-coupling reactions has been well-documented, 16 and most recently, tunable aryl alkyl ionic liquids containing different palladate counteranions have also been developed. 17 The use of a slight excess of styrene was essential to give a quantitative yield, as the use of 1 equiv Reaction conditions unless specified otherwise: 1.4 mmol of styrene, 1 mmol of aryl halide, 1.1 mmol of NaOAc, 2 g of TBAB, 0.1−0.2 mol % of monopalladium loading, 140 °C. NMR yield using 1,3,5-trimethoxybenzene as an internal standard.…”

Tetrakis(pentafluoroethyl)gallate, [Ga(C2F5)4]−, Ionic Liquids

“…The viscosities of the substituted TAAILs depicted in Figure 4 are following the same pattern in terms of the alkyl chain length, however, they show higher viscosities at all. The 4-OMe substituted ILs (12)(13)(14) exhibits the highest viscosities between 162-91 cP followed by 2-Me (7-10) at 139-77 cP and 2,4-F (15-18) at 126-67 cP. Following the Vogel-Fulcher-Tammann equation, viscosities decrease exponentially at higher temperatures and reach less than 50 cP at 60°C.…”

“…The combination with a dicyanamide anion [N(CN) 2 ] À results in very wide electrochemical windows, [13] while TAAILs with palladate anions gave access to catalytically active ionic liquids. [14] Weakly coordinating anions are well suited for ionic liquids, since positive effects were achieved by reduced ion interactions. [15] New TAAILs with weakly coordinating anions were synthesized previously containing boron as the central atom.…”

Hexacyanidosilicates with Functionalized Imidazolium Counterions

“…Compound Syntheses: Bromide salts [R‐Ph( n Bu)Im]Br with R = 2‐Me, 4‐Me, 2,4,6‐Me and 2‐MeO were prepared according to the literature . The synthesis of the starting compounds K 2 [Si(CN) 6 ], [2,4‐FPh( n Bu)Im]Br and [4‐BrPh( n Bu)Im]Br can be found in the supporting information.…”