705-08-8Relevant academic research and scientific papers
Quaternary Alkyl Ammonium Salt-Catalyzed Transformation of Glycidol to Glycidyl Esters by Transesterification of Methyl Esters
Tanaka, Shinji,Nakashima, Takuya,Maeda, Toshie,Ratanasak, Manussada,Hasegawa, Jun-Ya,Kon, Yoshihiro,Tamura, Masanori,Sato, Kazuhiko
, p. 1097 - 1103 (2018/02/14)
Catalytic transformation of glycidol while maintaining its epoxide moiety intact is challenging because the terminal epoxide that interacts with the hydroxyl group via a hydrogen bond is labile for the ring-opening reaction. We found that a quaternary alkyl ammonium salt catalyzes the selective transformation of glycidol to glycidyl esters by transesterification of methyl esters. The developed method can be applied to the synthesis of multiglycidyl esters, which are valuable epoxy resin monomers. Mechanistic studies revealed the formation of a binding complex of glycidol and quaternary alkyl ammonium salt in a nonpolar solvent and the generation of the alkoxide anion as a catalyst through the ring-opening reaction of the epoxide. Computational studies of the reaction mechanism indicated that the alkoxide anion derived from glycidol tends to abstract the proton of another glycidol rather than work as a nucleophile, initiating the catalytic transesterification. Payne rearrangement of the deprotonated glycidol, which produces a destabilized base that promotes nonselective reactions, is energetically unfavorable due to the double hydrogen bond between the anion and diol. The minimal interaction between the quaternary alkyl ammonium cation and the epoxide moiety inhibited the random ring-opening pathway leading to polymerization.
METHOD FOR PRODUCING GLYCIDYL ESTER
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Paragraph 0032; 0034-0038; 0040-0041, (2017/11/09)
PROBLEM TO BE SOLVED: To provide a production method which makes it possible to obtain glycidyl ester with high yields from the ester exchange reaction between ester and glycidol with a convenient catalyst in a mild reaction condition. SOLUTION: Glycidyl ester is produced by the ester exchange reaction between ester and glycidol in the presence of a polystyrene-carrying quaternary ammonium salt. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
Transition-metal-free aerobic oxidative cleavage of C-C bonds in α-hydroxy ketones and mechanistic insight to the reaction pathway
Liu, Hui,Dong, Chao,Zhang, Zeguang,Wu, Peiyu,Jiang, Xuefeng
supporting information, p. 12570 - 12574 (2013/02/22)
Clear cut: For the title reaction, O2, the ideal oxidant, was used as the only oxidizing reagent. The dimer intermediate (see scheme) and isotopic labeling control experiments with 18O2 partially disclosed the reaction mec
Enantioselective incorporation of carbon dioxide into epoxides catalyzed by optically active cobalt(II) complexes
Yamada, Wataru,Kitaichi, Yasunori,Tanaka, Hirotaka,Kojima, Tomohide,Sato, Mitsuo,Ikeno, Taketo,Yamada, Tohru
experimental part, p. 1391 - 1401 (2009/06/20)
The enantioselective chemical fixation of CO2 into an epoxide was developed using an optically active ketoimi-natocobalt(II) complex as a chiral Lewis acid. In the presence of a catalytic amount of the cobalt complex and amine base, enantioselective CO2 fixation with an epoxide proceeded with kinetic resolution to afford the corresponding carbonate along with unreacted epoxide, both of which were optically active. To improve their enantioselectivities, the ligand structures of the cobalt complexes and amine bases were examined. Thus, the optimized catalytic system was successfully applied to various epoxides to obtain the corresponding optically active cyclic carbonates and to recover epoxides with good-to-high enantioselectivities.
