26413-18-3Relevant academic research and scientific papers
Synthesis method of 1, 3-dithiane 1, 1, 3, 3-tetroxide
-
Paragraph 0015-0026, (2020/07/15)
The invention discloses a synthesis method of 1, 3-dithiane 1, 1, 3, 3-tetroxide, and belongs to the technical field of battery electrolyte. The preparation method comprises the following steps: taking 1, 3-propanedithiol and polyformaldehyde; adding a diethyl ether complex of boron trifluoride, carrying out heating reflux for 2-3 hours by taking chloroform as a solvent, then cooling to room temperature, separating out an organic layer for drying and concentration after water washing, dissolving residues with methanol, heating to boiling, filtering while the residues are hot, cooling a filtrate to room temperature, standing overnight at -20 to -25 DEG C, crystallizing and drying to obtain an intermediate product; dissolving the intermediate product into methylbenzene; adding sodium tungstate dehydrate into an obtained mixed solution at 0-5 DEG C, stirring for 10-15 minutes, dropwise adding hydrogen peroxide into the mixed solution, heating to 30-40 DEG C after dropwise adding, reactingfor 1-2 hours, adding water and sodium sulfite into the mixed solution, extracting by using acetonitrile, and distilling an organic layer under reduced pressure to remove the solvent so as to obtain1, 3-dithiane 1, 1, 3, 3-tetroxide. The synthesis method disclosed by the invention is simple, and the obtained 1, 3-dithiane 1, 1, 3, 3-tetraoxide is high in yield, high in purity and less in moisture.
Base-free Enantioselective C(1)-Ammonium Enolate Catalysis Exploiting Aryloxides: A Synthetic and Mechanistic Study
McLaughlin, Calum,Slawin, Alexandra M. Z.,Smith, Andrew D.
supporting information, p. 15111 - 15119 (2019/11/05)
An isothiourea-catalyzed enantioselective Michael addition of aryl ester pronucleophiles to vinyl bis-sulfones via C(1)-ammonium enolate intermediates has been developed. This operationally simple method allows the base-free functionalization of aryl esters to form α-functionalized products containing two contiguous tertiary stereogenic centres in excellent yield and stereoselectivity (all ≥99:1 er). Key to the success of this methodology is the multifunctional role of the aryloxide, which operates as a leaving group, Br?nsted base, Br?nsted acid and Lewis base within the catalytic cycle. Comprehensive mechanistic studies, including variable time normalization analysis (VTNA) and isotopologue competition experiments, have been carried out. These studies have identified (i) orders of all reactants; (ii) a turnover-limiting Michael addition step, (iii) product inhibition, (iv) the catalyst resting state and (v) catalyst deactivation through protonation.
Highly atom-economic, catalyst- and solvent-free oxidation of sulfides into sulfones using 30% aqueous H2O2
Jereb, Marjan
supporting information, p. 3047 - 3052,6 (2020/09/16)
Highly atom-efficient oxidation of sulfides into sulfones under solvent- and catalyst-free reaction conditions using a 30% aqueous solution of H 2O2 at 75 °C is reported. A structurally diverse set of phenyl alkyl-, phenyl benzyl-, benzyl alkyl-, dialkyl-, heteroaryl alkyl- and cyclic sulfides were transformed into sulfones regardless of the aggregate state and electronic nature of the substituents. In spite of the heterogeneous reaction mixtures throughout the work, no difficulties with stirring and reaction progress were noted. In numerous cases, only 10 mol% excess of H 2O2 was used, thus contributing considerably to the high atom economy of the process. Some solid substrates required a variable excess of hydrogen peroxide; however, the reactions were performed strictly without organic solvents. The transformation was demonstrated to be amenable for scale-up with both liquid and solid sulfides. In addition, isolation and purification of the crude products can be simply done with only filtration and crystallization.
