1842-38-2Relevant articles and documents
Tamagaki,Hatanaka
, p. 301 (1976)
Reaction of 1,3-bis(alkylseleno)allenes with diphenyl diazomethane
Shimizu,Miyasaka,Kamigata
, p. 7202 - 7204 (2001)
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Bulky Selenium Ligand Stabilized Trans-Palladium Dichloride Complexes as Catalyst for Silver-Free Decarboxylative Coupling of Coumarin-3-Carboxylic Acids
Bhuvanesh, Nattamai,Himanshi,Joshi, Hemant,Kumar, Anil,Kumar, Sunil,Meena, Neha,Reddy, S. Rajagopala,Shinde, Vikki N.
, (2022/01/11)
This report describes the syntheses of three new trans-palladium dichloride complexes of bulky selenium ligands. These complexes possess a Cl?Pd?Cl rotor spoke attached to a Se?Pd?Se axle. The new ligands and palladium complexes (C1?C3) were characterized with the help of NMR, HRMS, UV-Vis., IR, and elemental analysis. The single-crystal structure of metal complex C2 confirmed a square planar geometry of complex with trans-orientation. The X-ray structure revealed intramolecular secondary interactions (SeCH—Cl) between chlorine of PdCl2 and CH2 proton of selenium ligand. Variable-temperature NMR data shows coalescence of diastereotopic protons, which indicates pyramidal inversion of selenium atom at elevated temperature. The relaxed potential energy scan of C2 suggests a rotational barrier of ~12.5 kcal/mol for rotation of chlorine atom through Cl?Pd?Cl rotor. The complex C3 possesses dual intramolecular secondary interactions (OCH2—Cl and SeCH2—Cl) with stator ligand. Molecular rotor C2 was found to be a most efficient catalyst for the decarboxylative Heck-coupling under mild reaction conditions. The protocol is applicable to a broad range of substrates with large functional group tolerance and low catalyst loading (2.5 mol %). The mechanism of decarboxylative Heck-coupling reaction was investigated through experimental and computational studies. Importantly the reaction works under silver-free conditions which reduces the cost of overall protocol. Further, the catalyst also worked for decarboxylative arylation and decarboxylative Suzuki-Miyaura coupling reactions with good yields of the coupled products.
Metal-free synthesis of unsymmetrical selenides from pyridinium salts and diselenides catalysed by visible light
Ji, Liangshuo,Qiao, Jiamin,Li, Ankun,Jiang, Zeyi,Lu, Kui,Zhao, Xia
, (2021/05/04)
We report the first metal-free selenolations of pyridinium salts with diselenides to prepare unsymmetrical organoselenides catalysed by visible light. This protocol is an efficient and green method for the preparation of unsymmetrical organoselenides because metal-free conditions and readily accessible diselenides are used.
Sodium Selenosulfate from Sodium Sulfite and Selenium Powder: An Odorless Selenylating Reagent for Alkyl Halides to Produce Dialkyl Diselenide Catalysts
Chen, Chao,Jiang, Xuefeng,Ling, Hai,Liu, Yonghong,Xu, Qing,Yu, Lei
supporting information, p. 1698 - 1702 (2019/08/26)
Na 2 SeSO 3, which can be generated in situ by the reaction of Na 2 SO 3 with Se power, was found to be an odorless reagent for the selenenylation of alkyl halides to produce dialkyl diselenides. These products have been recently shown to be good catalysts for the Baeyer-Villiger oxidation of carbonyl compounds, for the selective oxidation of alkenes, or for the oxidative deoximation of oximes. By using aqueous EtOH as the solvent and avoiding the generation of a malodourous selenol intermediate, the selenylation reaction with Na 2 SeSO 3 is much more environmentally friendly than conventional methods. Owing to the cheap and abundant starting materials and selenium reagents, our novel synthetic method reduces the production costs of dialkyl diselenides as organoselenium catalysts, thereby advancing practical applications of organoselenium-catalysis technologies.