- Preparation method of 4-methyl-1,3,2-dioxathiane 2-oxide
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The invention discloses a preparation method of 4-methyl-1,3,2-dioxathiane 2-oxide. The preparation method comprises the following steps: 1, taking 1,3-butylene glycol and thionyl chloride as raw materials, dropwise adding thionyl chloride to 1,3-butylene glycol for a synthesis reaction, and controlling the reaction system temperature to be 35-45 DEG C, so as to obtain a reaction crude product 10-30 min after the thionyl chloride is dropwise added and when the reaction is finished; 2, performing reduced-pressure rotary evaporation on the reaction crude product for acid removal, controlling thetemperature of reduced-pressure rotary evaporation to be 35-45 DEG C and the time to be 15-30 min, so as to obtain a crude product subjected to acid removal; 3, adding an acylation reagent into the crude product subjected to acid removal for a reaction, after the reaction is finished, adding an alkaline aqueous solution until the pH value is 6-7; 4, performing standing layering, separating the organic phase and the aqueous phase, washing the organic phase to obtain a first crude product, and performing extraction on the aqueous phase to obtain a second crude product; and 5, merging the firstcrude product and the second crude product, performing reduced-pressure rectification, so as to obtain the target product 4-methyl-1,3,2-dioxathiane 2-oxide. The preparation method of the invention has the advantages that the yield, productivity and purity are greatly improved.
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Paragraph 0021; 0024-0033
(2018/05/16)
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- Preparation method for butylene glycol sulfite
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The invention relates to a preparation method for butylene glycol sulfite and belongs to the technical field of battery additives. The preparation method is characterized by comprising the following steps: performing transesterification on sulfurous dialkyl ester and dry butanediol in a rectifying reactor under an effect of a compound catalyst at 90 DEG C-180 DEG C, and then reacting for 2-10 hours, wherein the mole ratio of sulfurous dialkyl ester to dry butanediol is 1:(1.0-1.5) and the compound catalyst is the compound catalyst of alkyl sodium alkoxide and magnesium oxide; and after the ending of reaction, rectifying and recrystallizing, thereby obtaining the butylene glycol sulfite. The preparation method provided by the invention is low in risk of reaction raw materials, high in yield and free from acid side product.
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Paragraph 0016
(2017/07/11)
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- Chemo- and Regioselective Functionalization of Polyols through Catalytic C(sp3)-C(sp3) Kumada-Type Coupling of Cyclic Sulfate Esters
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This contribution describes a copper-catalyzed, C(sp3)-C(sp3) cross-coupling reaction of cyclic sulfate esters, a distinct class of electrophilic derivatives of polyols, with alkyl Grignard reagents to afford functionalized alcohol products in good yields. The method is operationally simple and highlights the potential of cyclic sulfate esters as highly reactive substrates in catalytic, chemoselective polyol transformations.
- Ramírez-Contreras, Rodrigo,Morandi, Bill
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supporting information
p. 3718 - 3721
(2016/08/16)
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- 2-Oxo-1,3,2-dioxathianes. I. Preparation of the Alkyl-substituted Derivatives
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2-Oxo-1,3,2-dioxathiane, all methyl- and several other alkyl-substituted 2-oxo-1,3,2-dioxathianes have been synthesized by condensing 1,3-alkanediols and thionyl chloride.The amount of the S==O-axial and S==O-equatorial isomers can be controlled by adding pyridine to the reaction mixture.
- Virtanen, Terttu,Nikander, Hannu
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p. 113 - 116
(2007/10/02)
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