Thermochemical Properties of Tunable Aryl Alkyl Ionic Liquids (TAAILs) based on Phenyl‐1H‐imidazoles

Abstract

Vaporization enthalpies of five different imidazolium based Tunable Aryl Alkyl Ionic Liquids (TAAILs) with a common bis(trifluoromethylsulfonyl)imide ([NTf2]) anion were measured using a Quartz Crystalline Microbalance (QCM) and by Thermogravimetric Analysis (TGA). The counter anion and the alkyl chain of these imidazolium‐based ionic liquids with one N‐aryl and one N‐alkyl substituent were kept constant to study the influence of the ortho‐ and para‐substituted aryl moieties on the vaporization enthalpies of these ionic liquids. For comparison, enthalpies of vaporization measured at elevated temperatures were adjusted to the reference temperature 298 K. Structure‐property relations between TAAILs and similarly shaped corresponding 1‐(R‐phenyl)‐imidazoles were analyzed. An incremental approach to predict vaporization enthalpies of ionic liquids by group contributions was suggested. The procedure is based on vaporization enthalpy of a starting IL and group contributions well established from molecular compounds.

Synthesis of alcohol ester 12 in 1, 8‐diazabicyclo [5.4.0] undec‐7‐ene (DBU)‐based Self‐separation catalytic system

“…From Figure , when anions are same, [ODBU]OH and [BDBU]OH decomposed at ca . 110 °C, by contrast, [ODBU]IM and [BDBU]IM could withstand high temperature of 134 °C and 145 °C, respectively, which is consistent with the feature that the thermal stability decreases significantly with increasing carbon chain . When there are same cations, the thermal stability of [BDBU]IM ([ODBU]IM) is higher than [BDBU]OH ([ODBU]OH).…”

Synthesis of 2, 2, 4‐trimethyl‐1, 3‐pentaerediol monoisobutyrate catalyzed by homogeneous catalysis‐liquid/liquid separation catalytic system based on Bibasic sites Ionic Liquids

“…3425 and 3,419 cm −1 (Figure 2(B)b, c and 2(C)a, c) proved the existence of carboxyl groups. [ 19 ] There was an obvious peak around 1,610 cm −1 in the spectrum of DBU cation group (Figure 2(C)), due to typical characteristic peak of C=N species in DBU ring.…”

Vaporization Thermodynamics of Morpholinium Based Ionic Liquids

“…Imidazolium‐based ILs have been studied extensively over the past decade [7,9] . On the other hand, very few studies exist on other classes of ILs, such as those based on morpholinium cation.…”

“…The synthesis and aggregation control of metal nanoparticles from Ru, Rh, Ir, and Pt in ionic liquids can be performed successfully, and nanoparticles have been investigated as catalysts for the solvent‐free hydrogenation of benzene to cyclohexane under mild conditions [2,3] . Knowledge and the ability to predict the physico‐chemical properties of ILs are indispensable for the practical application of ILs [7–9] . To further improve the quality of the materials, the thermal behaviour and thermodynamic properties of IL solvents should be carefully studied.…”