3112-88-7Relevant articles and documents
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Ito et al.
, p. 2254 (1970)
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Shirota et al.
, p. 3299 (1967)
On the important transition of sugar-based surfactant as a microreactor for C-S coupling in water: From micelle to vesicle
Ge, Xin,Lei, Qiuyun,Liao, Xiong,Liu, Xuemin,Song, Weili,Wu, Lei,Wu, Siyuan,Zhou, Shaodong
, (2021/09/15)
A reversible, temperature-induced micelle-to-vesicle transition of a sugar-based pseudogemini surfactant (C11D12) was employed for copper-catalyzed C-S coupling in water. The phase behavior and morphology of the C11D12 aqueous solution were investigated by DLS and cryo-TEM. The aggregates undergo a series of transitions upon increasing the temperature: spherical micelles were initially transformed into large vesicles, but they eventually transformed into smaller vesicles. The vesicular catalytic protocol accommodates an excellent substrate scope with moderate to high yields. The mechanisms of temperature-induced aggregate transition and vesicular catalysis were elucidated by experimental results and DFT calculations. It was revealed that the charge layer of the vesicle grants stronger nucleophilicity to the PhSO2-Cu-D12Ga intermediate. Furthermore, the aqueous reaction medium can be recycled and reused several times after easily separating the precipitated product.
Cobalt-Catalyzed Redox-Neutral Sulfonylative Coupling from (Hetero)aryl Boronic Acids, Ammonium Salts and Potassium Metabisulfite
Fan, Qiangwen,Le, Zhang-Gao,Xie, Zongbo,Yang, Liu,Zhang, Yingying,Zhu, Haibo
, (2022/01/08)
An efficient cobalt-catalyzed redox-neutral sulfonylative coupling to afford (hetero)aryl alkyl sulfones from boronic acids, ammonium salts and potassium metabisulfite has been realized. Commercially available and air-stable CoCl2, in combination with phenanthroline ligand, is sufficient to achieve rapid and high-yielding conversion of the reactants into the corresponding sulfones. This practical transformation proceeds smoothly through C?N bond cleavage under redox-neutral catalytic conditions and shows broad functional-group tolerance. Other carbon based electrophiles, including diaryliodonium salts, heteroaryl halides, and carbonates were compatible. Further transformation of aryl alkyl sulfones then allows conversion into olefins, alkenyl sulfones and halogenated sulfones, respectively, in a one-pot process.
Synthesis, spectral characterization, SC-XRD, HSA, DFT and catalytic activity of novel dioxovanadium(V) complex with aminobenzohydrazone Schiff base ligand: An experimental and theoretical approach
Ashfaq, Muhammad,Behjatmanesh-Ardakani, Reza,Fallah-Mehrjardi, Mehdi,Kargar, Hadi,Munawar, Khurram Shahzad,Tahir, Muhammad Nawaz
, (2021/07/28)
A new dioxovanadium(V) complex was prepared by the reaction of VO(acac)2 with a tridentate ONO donor Schiff base, derived by condensing 3-ethoxysalicylaldehyde and 4-aminobenzohydrazide. The structures of synthesized products were characterized spectroscopically through FT-IR, 1H & 13C NMR and by elemental composition through combustion analysis. The structure of the complex was determined with the help of single crystal X-ray crystallography. It was inferred from the diffraction data that the geometry around the central metal ion in the complex is distorted square pyramidal. The tridentate Schiff base ligand is bonded to the central metal through the oxygen of the carbonyl group, the deprotonated phenolic oxygen atom and the azomethine nitrogen. The pyramid base is completed by other oxo ligands that are in cis positions. The theoretical calculations, performed by DFT using B3LYP/Def2-TZVP level of theory, determined that the intended outcomes are in compliance with the actual consequences. Furthermore, the catalytic potential of the vanadium complex was explored for the selective oxidation of the aryl and alkyl sulfides to the corresponding sulfones in the presence of 30% aqueous H2O2 in ethanol. In this work, rPBE and B3LYP methods are used to locate transition structures and to compare free energies of reactants, transition structures and the products involved in the reaction. Analyzing nudge elastic band data shows that the barrier free energy for the oxidation of sulfide to sulfoxide and sulfone are 13 and 83 kcal.mol?1, respectively. The main advantages of the present catalytic study are high yields of the products, less time required for the completion of the reaction and simple work-out procedure.
