1694-20-8Relevant articles and documents
Cis/trans conversion of potassium derivatives of 2- and 4-nitrostilbenes
Todres, Zori V.
, p. 349 - 354 (1992)
Potassium derivatives of 2- and 4-nitrostilbenes exist in non-dissociating solvents as coordination complexes with localization of the metal at the nitro group.Stilbene components of the complexes undergo cis/trans conversion, the extent of which does not
A new recyclable Pd catalyst supported on vertically aligned carbon nanotubes for microwaves-assisted Heck reactions
Janowska, Izabela,Chizari, Kambiz,Olivier, Jean-Hubert,Ziessel, Raymond,Ledoux, Marc Jacques,Pham-Huu, Cuong
, p. 663 - 670 (2011)
Palladium supported on vertically aligned multi-walled carbon nanotubes (Pd/VA-CNTs) is used as catalyst for the C-C coupling reactions of p-iodonitrobenzene with styrene and ethyl acrylate under microwaves irradiation. Pd/VA-CNTs catalyst exhibits higher
Mild and rational synthesis of palladium complexes comprising C(4)-bound N-heterocyclic carbenes
Kluser, Evelyne,Neels, Antonia,Albrecht, Martin
, p. 4495 - 4497 (2006)
Oxidative addition of pyridyl-functionalised 4-iodoimidazolium salts to palladium(0) gives catalytically active complexes in which the N-heterocyclic carbene is bound to the palladium(ii) centre in a non-classical bonding mode via C(4). The Royal Society of Chemistry 2006.
Oxazoline Chemistry. Part 11: Syntheses of natural and synthetic isoflavones, stilbenes and related species via C-C bond formation promoted by a Pd-oxazoline complex
Eisnor, Charles R.,Gossage, Robert A.,Yadav, Paras N.
, p. 3395 - 3401 (2006)
The complex trans-[PdCl2(2-ethyl-2-oxazoline- κ1N)2] (1) is shown to be an active and oxidatively robust catalyst for C-C bond forming reactions (Heck, Sonogashira, Ullmann, Miyaura-Suzuki, etc.). These reactions can be carried out in air without rigorous solvent/substrate purification and in the absence of additional free ligand. The general methodology described above has been applied to the high yield and regio-selective formation, via Miyaura-Suzuki coupling, of natural and synthetic isoflavones (i.e., isoflavone, 2′-methylisoflavone [7b], 3′-methylisoflavone [7c] and 3′,4′-benzoisoflavone: [7d]). Compounds 7c and 7d are previously unknown. In addition, the synthesis of (E)-tris-O-methylresveratrol and (E)-3,5-dimethoxystilbene is also described; the former is a recognized anti-cancer agent while the latter is a biologically active extract from the bark of the conifer species Pinus armandii. Both of these latter products are produced as a result of a Heck coupling reaction promoted by 1.
Application of an air stable Pd oxazoline complex for Heck, Suzuki, Sonogashira and related C-C bond-forming reactions
Gossage, Robert A.,Jenkins, Hilary A.,Yadav, Paras N.
, p. 7689 - 7691 (2004)
The novel complex trans-[PdCl2(η1-N-2-ethyl-2- oxazoline)2] is shown to be an active and oxidatively robust catalyst for C-C bond-forming reactions (Heck, Sonogashira, Ullman, Suzuki), which can be carried out in air witho
Enhanced Heck reaction on flower-like Co(Mg or Ni)Al layered double hydroxide supported ultrafine PdCo alloy nanocluster catalysts: The promotional effect of Co
Li, Jin,Song, Ying,Wang, Yajuan,Zhang, Hui
, p. 17741 - 17751 (2019)
A series of PdCo alloy nanocluster (NC) catalysts x-PdCor/Co(Mg or Ni)Al-LDH (x: Pd loading, r: Co/Pd molar ratio) were synthesized by immobilizing ultrafine PdCor-PVP NCs on flower-like layered double hydroxide (LDH) supports. The s
N-Heterocyclic carbene palladium (II)-pyridine (NHC-Pd (II)-Py) complex catalyzed heck reactions
Li, Dan,Tian, Qingqiang,Wang, Xuetong,Wang, Qiang,Wang, Yin,Liao, Siwei,Xu, Ping,Huang, Xin,Yuan, Jianyong
supporting information, p. 2041 - 2052 (2021/05/25)
A mild, efficient, and practical catalytic system for the synthesis of highly privileged stilbene pharmacophores is reported. This system uses N-heterocyclic carbene palladium (II) Pyridine (NHC-Pd (II)-Py) complex to catalyze the formation of carbon-carbon bonds between olefin derivatives and various bromide. This simple, gentle and user-friendly method can offer a variety of stilbene products in excellent yields under solvent-free condition. And its scale-up reaction has excellent yield and this system can be applied to industrial fields. The utility of this method is highlighted by its universality and modular synthesis of a series of bioactive molecules or important medical intermediates.
Immobilized Pd on a NHC-functionalized metal-organic FrameworkMIL-101(Cr): An efficient heterogeneous catalyst in the heck and copper-free Sonogashira coupling reactions
Niknam, Esmaeil,Panahi, Farhad,Khalafi-Nezhad, Ali
supporting information, (2021/01/12)
A heterogeneous palladium catalyst system based on immobilization of palladium moieties on a N-heterocyclic carbene (NHC) modified metal organic framework (MOF) was developed for the Heck and copper-free Sonogashira coupling reactions. In order to prepare this catalyst system, first, MIL-101(Cr) was functionalized with NHC moieties through a post synthetic modification (PSM) approach, and then Pd metal was stabilized on the prepered MIL-101(Cr)-NHC substrate. This material was characterized using various microscopic and spectroscopic techniques and then was used as an efficient heterogeneous Pd catalyst system in the Heck and copper-free Sonogashira reactions. Results of the heterogeneity tests showed that the Pd-NHC-MIL-101(Cr) catalyst can efficiently catalyzed these coupling reactions heterogeneously and no remarkable changes observed in the morphology and structure of MIL-101(Cr) template during the reaction progress. Also, existence of palladium nanoparticles immobilized on the MOF structure affirmed by the TEM and XPS analysis confirmed the oxidation state of Pd. A variety of alkene and alkyne derivatives were synthesized in good to excellent yields using this heterogeneous Pd catalyst system under normal conditions. More importantly Pd-NHC-MIL-101(Cr) catalyst was simply recovered from the reaction medium without remarkable decreasing in its catalytic activities after five times of reusability. The ICP analysis showed the very low Pd and Cr metals leaching, representing high stability and applicability of this catalyst in Pd coupling reactions.
Immobilizing palladium on melamine-functionalized magnetic nanoparticles: An efficient and reusable phosphine-free catalyst for Mizoroki–Heck reaction
Aryanasab, Fezzeh,Shabanian, Meisam,Laoutid, Fouad,Vahabi, Henri
, (2021/02/22)
A highly efficient and stable heterogeneous catalyst was successfully prepared by anchoring palladium(0) onto melamine-functionalized Fe3O4 magnetic nanoparticles (MNPs-Mel-Pd). With the aid of amine functional groups, melamine was covalently bonded on epoxy functionalized magnetic nanoparticles and then Pd(0) was immobilized on this support with high dispersion. The prepared nanocatalyst exhibits excellent catalytic activity for C-C cross coupling (Mizoroki–Heck) of various aryl halides (iodide, bromides, and chrlorides) with olefins under mild reaction condition in relatively short reaction times. The synthesized nanocatalyst was characterized using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and X-ray photoelectron spectroscopy (XPS) techniques. The loading level of Pd in MNPs-Mel-Pd catalyst was measured to be 1.26 × 10?3 mol g?1 by atomic absorption spectroscopy (AAS). In addition, the catalyst can be easily separated and recovered from the reaction mixture by using an external magnet. The heterogeneity of the catalyst was confirmed by the hot filtration test, which was reused for at least six times under the optimized conditions without any significant loss of its activity.
