58-95-7Relevant articles and documents
Synthesis and characterization of a new acid molten salt and the study of its thermal behavior and catalytic activity in Fischer esterification
Zaharani, Lia,Khaligh, Nader Ghaffari,Johan, Mohd Rafie,Gorjian, Hayedeh
, p. 7081 - 7088 (2021/05/03)
A new acid molten salt was prepared and its structure elucidation was conducted by FTIR, 1D NMR, 2D NMR, and mass spectrometry. Further support to elucidate the chemical structure of the 1H,4H-piperazine-N,N′-diium ring of the new acid molten salt was achieved by1H and13C NMR, and COSY analyses of 1H,4H-piperazine-N,N′-diium dibromide, which is synthesized and characterized for the first time in the current work. The analysis of FTIR and NMR spectra as well as pH and titrimetric analysis excluded the formation of [SO4]2?and the presence of an excess of H2SO4. Moreover, no distinguishing peak was detected for the acid proton of [HSO4]?in DMSO-d6. The thermal phase transition and thermal stability of the acid molten salt were also recorded, which approved the strong interaction between a dication and hydrogen sulfate anions. According to the acidity of the new molten salt, we encourage the study of its catalytic activity for the acetylation ofn-pentanol using glacial acetic acid. Pentyl acetate was obtained in 89.0% conversion and 78.0% isolated yield. The1H NMR spectrum of the residue showed an excess of HOAc together with molten salt, whereas the1H NMR spectrum of the upper phase exhibited pure pentyl acetate. After separation of the upper phase, the residue was concentrated and used in the next run without further purification. No significant changes in the chemical structure and catalytic activity of the new molten salt were observed even after the 5th run. Two chiral alcohols, including (?)-menthol and (+)-borneol, as well as α-tocopherol (α-TCP) were also acetylated with acetic acid in the presence of the new acid molten salt under optimized reaction conditions, which afforded the desired acetates in high yields.
4-Imidazol-1-yl-butane-1-sulfonic acid ionic liquid: Synthesis, structural analysis, physical properties and catalytic application as dual solvent-catalyst
Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie,Juan, Joon Ching
, p. 866 - 878 (2019/07/12)
4-Imidazol-1-yl-butane-1-sulfonic acid (ImBu-SO3H) has been successfully synthetized and fully characterized by FT-IR and high-resolution NMR spectroscopy (1H, 13C). The “plausible” alternative structures of ImBu-SO3H were discussed on the basis of its NMR data. The ionic liquid showed interesting dual solvent-catalyst property, which was studied experimentally for the acetylation of a variety of functionalized alcohols, phenols, thiols, amines and α-tocopherol (α-CTP) as the most active form of vitamin E with acetic anhydride and which provided good yields within a short reaction time. ImBu-SO3H was successfully recycled by product extraction with an average recovered yield of 82% for 5 subsequent runs. The catalytic activity of the recycled ImBu-SO3H showed almost no loss even after five consecutive runs.
Vitamin E acetate preparation method (by machine translation)
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Paragraph 0013, (2019/01/06)
The invention relates to a technical field of chemical synthesis, in particular relates to a vitamin E acetate preparation method, in order to trimethyl [...][...] as raw materials, innovative in a sulfuric acid and paratoluene sulfonic acid under acidic conditions, using magnesium sulfate as a catalyst, greatly improves the catalytic efficiency; in addition, in concentrated hydrochloric acid and ethyl acetate under the reaction environment, esterification synthetic vitamin E acetate efficiency is higher; and, synthetic route of this invention relates to the reaction of the routine chemical reaction, mild reaction conditions, simple operation, is suitable for industrial. (by machine translation)
