622-38-8Relevant articles and documents
Radical Ion Probes. 7. Behavior of a "Hypersensitive" Probe for Single Electron Transfer in Reactions Not Involving Electron Transfer
Tanko, James M.,Brammer Jr., Larry E.
, p. 5550 - 5556 (1997)
1-Methyl-5,7-di-tert-butylspiro[2.5]octa-4,7-dien-6-one (8) and 1,1-dimethyl-5,7-di-tert-butylspiro-[2.5]octa-4,7-dien-6-one (1) react with thiophenoxide ion to produce cyclopropane ring-opened products. Thermodynamic considerations effectively rule out any possibility that single electron transfer is involved in theses reactions; the process PhS- + substrate → PhS. + substrate.- is endothermic by over 50 kcal/moll Nucleophilic attack occurs both at the least- and most-hindered carbons of the cyclopropyl group, and the product ratio (R(1°/2°) from 8 and A(1°/3°) from 1, where 1°, 2°, and 3° refer to the regioisomeric phenyl sulfides formed from these substrates) is found to vary with solvent. In dipolar, aprotic solvents, nucleophilic attack occurs preferentially at the least-hindered carbon of the cyclopropyl group (A(1°/2°) and A(1°/3°) ≈ 4-5), consistent with an SN2 mechanism. In protic solvents, products arising from nucleophilic attack at the more-substituted carbon of the cyclopropyl group become increasingly important, consistent with the onset of a carbocationic (SN2(C+)) pathway. The strengths and weaknesses of 1 and 8 as probes for single electron transfer are discussed in the context of these results.
A mild and chemoselective CALB biocatalysed synthesis of sulfoxides exploiting the dual role of AcOEt as solvent and reagent
Anselmi, Silvia,Liu, Siyu,Kim, Seong-Heun,Barry, Sarah M.,Moody, Thomas S.,Castagnolo, Daniele
supporting information, p. 156 - 161 (2021/01/14)
A mild, chemoselective and sustainable biocatalysed synthesis of sulfoxides has been developed exploiting CALB and using AcOEt with a dual role of more environmentally friendly reaction solvent and enzyme substrate. A series of sulfoxides, including the drug omeprazole, have been synthesised in high yields and with excellent E-factors.
Palladium complex containing meta-position carborane triazole ligand and preparation method and application of palladium complex
-
Paragraph 0041-0043, (2020/08/07)
The invention relates to a palladium complex containing a meta-position carborane triazole ligand and a preparation method and application of the palladium complex. The palladium complex is prepared by the following steps: (1) dropwise adding an n-BuLi solution into a meta-position carborane m-C2B10H12 solution, carrying out stirring and reacting, then adding 3-propargyl bromide for a reaction again, and after the reaction is finished, carrying out separating to obtain 1,3-dipropargyl meta-carborane; and (2) under the catalytic condition of a catalyst CuI, carrying out a reaction on 1,3-dipropargyl meta-carborane and aryl azide, then adding PdCl2 into a reaction system, continuing the reaction, and after the reaction is finished, carrying out separation to obtain the palladium complex containing the meta-carborane triazole ligand. Compared with the prior art, the preparation method provided by the invention is simple and green; the complex can efficiently catalyze a coupling reaction of mercaptan and halogenated hydrocarbon to synthesize thioether compounds; reaction conditions are mild, substrate universality is good, catalytic efficiency is high, and few byproducts are produced;and the catalyst has high stability and is not sensitive to air and water.