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Cellulose-derived platform chemicals offer viable substitutes for most petroleumbased polymers and also enable the development of novel functional materials. In the focus of this work are thermophysical and thermochemical studies of dihydro-levoglucosenone (Cyrene) and levoglucosenone, which are considered as potential "green" replacements for industrial polar aprotic solvents. The densities, viscosities, absolute vapor pressures, and combustion energies of cyrene and levoglucosenone were measured in this work. The thermodynamic properties of levoglucosan derivatives are reliable for thermochemical calculations and used to calculate reaction enthalpies of valorization of the cellulose component of biomass. These enthalpies of reaction are useful in the further optimization and development of sustainable syntheses of commodity chemicals and fuels from biomass. The data provided in this work will aid researchers and engineers as the use of these new solvents grows.

Conversion of epichlorohydrin to glycidyl ethers creates versatile precursors that can be transformed into a variety of molecular species with glycerol skeletons, enabling the design of molecules with highly tailored functionalities. The synthesis of 2,2,2-trifluoroethyl glycidyl ether (TFGE, IUPAC name: 2-[(2,2,2-trifluoroethoxy) methyl]oxirane, CAS# 1535-91-7) was optimized to provide high yield/selectivity and good "green metrics." TFGE was then used as a platform molecule in the synthesis of asymmetric glycerol 1,3-diether-2-alcohol derivatives, which were subsequently transformed to 1,2,3-triethers or 1,3-diether-2-ketones. The density, viscosity, and CO 2 solubility of each molecule were measured and compared with those of other glycerol-derived compounds as well as compounds with similar functional groups. Furthermore, quantum chemical calculations were performed to understand the structure-property-performance relationships of these molecules for CO 2 absorption. Based on the results in this work, we foresee that TFGE (and similar glycidyl ethers) would offer great flexibility in molecular design of green solvents and precursors to more complex compounds.

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Etherification with high selectivity and yield has been one of the challenges for expanding the realm of glycerol transformations. In this work, a small glycerol triether molecule, 1,2,3-triethoxypropane (1,2,3-TEP, CAS 162614-45-1), was designed and synthesized through a two-step strategy using epichlorohydrin as the starting material with ethanol and bromoethane as etherification reagents. The overall yield (after rigorous distillation) was 43.9%, higher than those of methods previously published in the literature. Thermophysical properties for 1,2,3-TEP are herein reported for the first time. Densities and viscosities measured at 1 atm from 20 to 80 °C show that 1,2,3-TEP is a less dense and less viscous liquid than glycerol and the corresponding 1,3-diether intermediate, 1,3-diethoxypropan-2-ol (1,3-DEP, CAS #4043-59-8). CO 2 solubility in 1,2,3-TEP was investigated under pressures of 2−8 atm at 30, 45, 60, and 75 °C with respective K H values of 46.2, 57.4, 69.4, and 81.7 atm, enabling reliable predictions on CO 2 solubility within this range of temperature and pressure conditions. Comparison of Henry's law constants and vapor pressure between 1,2,3-TEP and diglyme from 0 to 75 °C has indicated its potential as an alternative CO 2 capture solvent to those used in the Selexol process. 1,2,3-TEP showed broad miscibility with common solvents except water. The dipole moment of the minimum energy structure in the gas phase is calculated to be 1.47 D, but this value increases to 2.5−2.7 D in common solvents. The data obtained in this work are meaningful in guiding the further synthesis of a series of glycerol triether derivatives and developing uses for 1,2,3-TEP and related compounds.

Reports of imidazoliumionic liquids (ILs) with at least one benzylic substituent bound to the imidazolium cation are far less common than the ubiquitous 1-alkyl-3methylimidazolium ILs ([C n mim][X]). Yet, there is significant motivation to determine structure−property relationships for imidazolium-based ILs with at least one benzylic substituent. Not only are these ILs just as straightforward to synthesize as [C n mim][X] ILs, but ILs with benzylic substituents are also representative segments of poly(ILs) and ionenes where imidazolium cations with benzylic groups are commonly found. This report focuses on the effects of benzyl and methylbenzyl substituents on the density and viscosity of a series of imidazolium cations paired with bis[(trifluoromethyl)sulfonyl]imide (more commonly known as bistriflimide) ([Tf 2 N] − ) anions. Furthermore, the solubility of CO 2 in 1-benzyl-3-methylimidazolium bistriflimide [Bnmim][Tf 2 N] (CAS: 433337-24-7) was measured at 303.15, 318.15, 333.15, and 348.15 K at pressures in the range of 1−9 bar.

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