220466-27-3Relevant articles and documents
Chemical-Reductant-Free Electrochemical Deuteration Reaction using Deuterium Oxide
Cheng, Xu,Li, Guigen,Liu, Ruoyu,Liu, Xu,Qiu, Jiaxing
supporting information, p. 13962 - 13967 (2020/06/10)
We report a method for the electrochemical deuteration of α,β-unsaturated carbonyl compounds under catalyst- and external-reductant-free conditions, with deuteration rates as high as 99 percent and yields up to 91 percent in 2 h. The use of graphite felt for both the cathode and the anode was key to ensuring chemoselectivity and high deuterium incorporation under neutral conditions without the need for an external reductant. This method has a number of advantages over previously reported deuteration reactions that use stoichiometric metallic reductants. Mechanistic experiments showed that O2 evolution at the anode not only eliminates the need for an external reductant but also regulates the pH of the reaction mixture, keeping it approximately neutral.
Nickel nanoparticles supported on diphenylphosphinated poly(vinyl alcohol-co-ethylene) as a new heterogeneous and recyclable catalyst for Mizoroki–Heck reactions
Ebrahimzadeh, Farzaneh
, p. 541 - 546 (2017/10/03)
Nickel nanoparticles (NiNPs) supported on diphenylphosphinated poly(vinyl alcohol-co-ethylene) (DPP-PVA-co-PE) were synthesised by first reacting poly(vinyl alcohol-co-ethylene) with chlorodiphenylphosphine (ClPPh2) under basic conditions and then treating the product with Ni(OAc)2 followed by reduction with NaBH4. (DPP-PVA-co-PE)-NiNPs, a new metallised polymer, was then shown to efficiently catalyse Mizoroki–Heck reactions of aryl iodides, bromides or activated chlorides with olefins such as styrene and n-butyl acrylate in dimethylformamide. In contrast with other polymer-supported catalysts, the main advantage of this method is the low cost of the catalyst due to the simple synthetic route using easily obtained materials and good recoverability. Transmission electron microscopy and X-ray diffraction measurements were used to show the high metal dispersion and small sizes of Ni nanoparticle on the surface of the modified polymer. DPP-PVA-co-PE-NiNPs could be recycled several times.
Preparation and characterization of palladium nanoparticles supported on phosphinated poly(Vinyl Alcohol) as new recyclable catalyst and their application for heck cross-coupling reactions
Ebrahimzadeh, Farzaneh,Tamami, Bahman
, p. 144 - 157 (2015/05/20)
Diphenylphosphinated poly(vinyl alcohols) (DPP-PVA) were synthesized by the insertion of chlorodiphenylphosphine to PVA in the presence of triethyl amine as base. The structure of this new polymer was confirmed by FT-IR and NMR spectroscopy. This polymer can be used as ligand for the preparation of nanoparticles of palladium. The complexation of PVA-grafted phosphinite with palladium(II) acetate was carried out to obtain the heterogeneous catalytic system. X-ray diffraction techniques, X-ray photoelectron spectroscopy, and transmission electron microscopy imaging revealed that palladium was dispersed into the nanometer scale through the support. This catalytic system showed excellent activity in the cross-coupling Heck reactions of olefinic compounds with aryl iodides, bromides as well as chlorides and gave high yields within short reaction times. Elemental analysis of Pd by the inductively coupled plasma technique on the supported catalyst exhibited low leaching of the metal into the solution. The catalyst can be reused several times in the repeated Heck reaction cycles without considerable loss in its activity.