18910-24-2Relevant academic research and scientific papers
Synthesis, crystal structure, and catalytic activity of bridged-bis(N-heterocyclic carbene) palladium(II) complexes in selective Mizoroki-Heck cross-coupling reactions
El Ali, Bassam,Fettouhi, Mohammed,Iali, Wissam,Mansour, Waseem,Suleiman, Rami
, (2021/08/09)
A series of three 1,3-propanediyl bridged bis(N-heterocyclic carbene)palladium(II) complexes (Pd-BNH1, Pd-BNH2, and Pd-BNH3), with + I effect order of the N-substituents of the ligand (isopropyl > benzyl > methoxyphenyl), was the subject of a spectroscopic, structural, computational and catalytic investigation. The bis(NHC)PdBr2 complexes were evaluated in Mizoroki-Heck coupling reactions of aryl bromides with styrene or acrylate derivatives and showed high catalytic efficiency to produce diarylethenes and cinnamic acid derivatives. The X-ray structure of the most active palladium complex Pd-BNH3 shows that the Pd(II) center is bonded to the two carbon atoms of the bis(N-heterocyclic carbene) and two bromide ligands in cis position, resulting in a distorted square planar geometry. The NMR data of Pd-BNH3 are consistent with a single chair-boat rigid conformer in solution with no dynamic behavior of the 8-membered ring palladacycle in the temperature range 25–120 °C. The catalytic activities of three Pd-bridged bis(NHC) complexes in the Mizoroki-Heck cross-coupling reactions were not found to have a direct correlation with +I effect order of the N-substituents of the ligand. However, a direct correlation was found between the DFT calculated absolute softness of the three complexes with their respective catalytic activity. The highest calculated softness, in the case of Pd-BNH3, is expected to favor the coordination steps of both the soft aryl bromides and alkenes in the Heck catalytic cycle.
Cu/Fe-Cocatalyzed Formation of β-Ketophosphonates by a Domino Knoevenagel-Decarboxylation-Oxyphosphorylation Sequence from Aromatic Aldehydes and H-Phosphonates
Zhou, Mingxin,Zhou, Yao,Song, Qiuling
supporting information, p. 10654 - 10658 (2015/07/20)
A domino Knoevenagel-decarboxylation-alkene difunctionalization sequence has been developed for the conversion of benzaldehydes into β-ketophosphonates, catalyzed by a cooperative Cu/Fe system, whereby CP and CO bonds are formed simultaneously in a one-pot reaction. The reaction proceeds in good yields and with a broad substrate scope and environmentally benign conditions.
One-pot synthesis of l-dopa-functionalized water-dispersible magnetite nano-palladium catalyst and its application in the Suzuki and Heck reactions in water: A novel and highly active catalyst
Niu, Jianrui,Wang, Fushan,Zhu, Xiaohang,Zhao, Jiahui,Ma, Jiantai
, p. 37761 - 37766 (2014/11/07)
A palladium catalyst supported on water-dispersible magnetite nanoparticles end-functionalized with amino and carboxyl groups was successfully prepared by a facile one-pot template-free method combined with a metal adsorption-reduction procedure. It was characterized by TEM, XRD, XPS, FT-IR and VSM. This catalyst exhibits excellent catalytic activity for Suzuki and Heck reactions in water. Furthermore, the newly developed catalyst is easy to be recovered and recycled by magnetic separation from aqueous phase reactions. More importantly, the catalyst revealed high efficiency and high stability under the reaction conditions and during recycling stages. This catalyst can be used consecutively six times without significant loss in catalytic activity. the Partner Organisations 2014.
Reusable and sustainable nanostructured skeleton catalyst: Heck reaction with nanoporous metallic glass Pd (PdNPore) as a support, stabilizer and ligand-free catalyst
Kaneko, Tetsuro,Tanaka, Shinya,Asao, Naoki,Yamamoto, Yoshinori,Chen, Mingwei,Zhang, Wei,Inoue, Akihisa
supporting information; experimental part, p. 2927 - 2932 (2011/12/16)
Nanoporous metallic glass palladium (PdNPore), which was fabricated by de-alloying of a glassy metallic alloy Pd30Ni50P 20, exhibited a remarkable catalytic activity for the Heck reaction of versatile aryl iodides and aryl bromides. Moreover, the PdNPore can be reused several times without a significant loss of catalytic activity, and the PdNPore has ahigher resistance to leaching than palladium black and palladium on carbon. Copyright
Linear polystyrene-stabilized PdO nanoparticle-catalyzed mizoroki-heck reactions in water
Ohtaka, Atsushi,Yamaguchi, Tomohiro,Teratani, Takuto,Shimomura, Osamu,Nomura, Ryoki
experimental part, p. 9067 - 9076 (2012/01/03)
Linear polystyrene-stabilized PdO nanoparticles (PS-PdONPs) were prepared by thermal decomposition of Pd(OAc)2 in the presence of polystyrene. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated the production of PdO nanoparticles. The loading of palladium was determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). PS-PdONPs exhibited high catalytic activity for Mizoroki-Heck reactions under air in water and could be recycled without loss of activity.
Metal-polymer hybrid material as a catalyst for the heck coupling reaction under phosphine-free conditions
Ul Islam, Rafique,Witcomb, Michael J.,Scurrell, Michael S.,Van Otterlo, Willem,Van Der Lingen, Elma,Mallick, Kaushik
experimental part, p. 3561 - 3572 (2011/10/02)
A method is described for making a poly-aminophenol-based hybrid material by in situ polymerization of aminophenol using palladium acetate as the oxidant. The oxidative polymerization of aminophenol leads to the formation of poly-aminophenol, while the reduction of palladium acetate results in the formation of palladium nanoparticles. The palladium nanoparticles were found to be highly dispersed and stabilized throughout the polymer matrix. The hybrid nanocomposite material showed excellent catalytic efficiency with respect to a Heck coupling reaction at a relatively low temperature and under flexible conditions.
N-Hydroxybenzimidazole inhibitors of ExsA MAR transcription factor in Pseudomonas aeruginosa: In vitro anti-virulence activity and metabolic stability
Grier, Mark C.,Garrity-Ryan, Lynne K.,Bartlett, Victoria J.,Klausner, Kevin A.,Donovan, Peter J.,Dudley, Caroline,Alekshun, Michael N.,Ken Tanaka,Draper, Michael P.,Levy, Stuart B.,Kim, Oak K.
scheme or table, p. 3380 - 3383 (2010/08/06)
ExsA is a multiple adaptational response (MAR) transcription factor, regulating the expression of a virulence determinant, the type III secretion system (T3SS) in Pseudomonas aeruginosa. Non-cytotoxic, non-antibacterial N-hydroxybenzimidazoles were identified as effective inhibitors of ExsA-DNA binding, and their potential utility as anti-virulence agents for P. aeruginosa was demonstrated in a whole cell assay. Select N-hydroxybenzimidazole inhibitors were stable in an in vitro human liver microsomal assay.
