7445-47-8Relevant articles and documents
Retention Indices and Sorption Enthalpies of Pentaerythritol and С2–С8 Acid Esters on Nonpolar Stationary Phases
Emel’yanov, V. V.,Krasnykh, E. L.,Portnova, S. V.
, p. 2168 - 2176 (2020/10/08)
Abstract: The retention and sorption enthalpy characteristics of 38 pentaerythritol esters of C2–C8 carboxylic acids of different structures were determined by gas-liquid chromatography on a nonpolar phase in the temperature range 433.2–563.2 K. The molecular structure was shown to affect the temperature dependence of the retention indices of the esters. The average change in the sorption enthalpy of pentaerythritol tetraesters per CH2 group is lower in magnitude than the similar contribution for normal alkanes. The excess mixing enthalpy at 298.2 K was evaluated for four fully substituted pentaerythritol esters.
Action of Organoaluminum Reagents on Esters: Alkene Production and the Degradation of Synthetic Lubricants
Slaughter, Jonathan,Molyneux, Samuel A.,Peel, Andrew J.,Wheatley, Andrew E. H.
supporting information, p. 395 - 408 (2019/01/11)
Reactions of methylaluminum reagents with ester-based lubricating oils are mimicked through the reaction of trimethylaluminum (TMA) with tetraesters C(CH2OC(O)R)4 (R = C5H11 4Pent, Bn 4Bn). Using a 2:1 stoichiometry gave adduct 4Pent(TMA)4. NMR spectroscopy on 1:1-12:1 TMA/4Pent systems suggested 4Pent gave dimethylated adduct C5H11CMe2OAlMe2(TMA), 2Pent(TMA). Similar combination of TMA with 4Bn at raised temperatures transformed 4Bn into C(CH2OAlMe2)4(2Bn)4 5(2Bn)4 by sequential reaction of each ester group. Doubly reacted {BnC(O)OCH2}2C(CH2OAlMe2)2(2Bn)2 7Bn(2Bn)2 was isolated and characterized. A Mitsubishi molecule could also be isolated, its formation rationalized by the elimination of 2Bn and TMA from 5(2Bn)4. The action of MenAlCl3-n (n = 1, 1.5, 2) was studied initially on monoester BnC(O)OMe 1Bn. Combining excess Me2AlCl with 1Bn gave adduct 1Bn(Me2AlCl) and small amounts of dimethylated BnCMe2OAlMe2(Me2AlCl), 2Bn(Me2AlCl), and MeOAlCl2 10. 2Bn(Me2AlCl) was fully characterized and, in the presence of 10, acted as a source of 2Bn(MeAlCl2). From this species, a mixture of alkenes could be generated by formal elimination of Me3Al2(OH)Cl2 13, the decomposition of which was presumed to also explain MeH observation. Replacing Me2AlCl with aluminum sesquichloride or MeAlCl2 led to progressively more sluggish but similar reactions. Using MenAlCl3-n (n = 1, 1.5, 2) with tetraesters suggested similar reactivity to monoesters.
Microwave-promoted synthesis of polyol esters for lubrication oil using a composite catalyst in a solvent-free procedure
Zhang, Fengxiu,Zhang, Guangxian
experimental part, p. 178 - 184 (2011/03/23)
A rapid, highly efficient and green synthetic approach to polyol esters for lubrication oils is proposed. Using sulfuric acid and p-toluene sulfonic acid as a composite catalyst and C5-C9 straight-chain monocarboxylic acids, with pentaerythritol (PE) and dipentaerythritol (di-PE) as starting materials, a series of lubrication oil polyol esters were synthesized in the absence of solvent under microwave irradiation. Compared with the conventional synthetic method, our proposed microwave method exhibits advantages, including higher yields, shorter reaction times and lower reaction temperatures. The viscosity coefficients of the products at 40 °C and their refractive indices at 25 °C were investigated. In addition, the thermal behavior of the starting materials under microwave irradiation was also investigated. The results reveal that the microwave absorbance of n-pentanoic acid is stronger than that of n-hexanoic acid and that of n-heptanoic acid is stronger than that of n-octanoic acid. The microwave absorbance of di-PE is also stronger than that of PE.
