389091-50-3Relevant articles and documents
Catalysis with palladium colloids supported in poly(acrylic acid)-grafted polyethylene and polystyrene
Bergbreiter, David E.,Kippenberger, Andrew,Zhong, Zhenqi
, p. 1343 - 1350 (2006)
Grafts of poly(acrylic acid) on polyethylene powder (PE-g-PAA) or polystyrene (PS-g-PAA) can be used to support Pd(O) crystallites that function like a homogeneous Pd(O) catalyst in some reactions. These Pd-PE-g-PAA catalysts were active in allylic substitution reactions in the presence of added phosphine ligand. A catalyst analogous to the Pd-PE-g-PAA powder catalyst on polystyrene (Pd-PS-g-PAA) was similarly active for allylic substitution and could also be used in Heck reactions at 80-100°C in N,N-dimethylacetamide (DMA). Analysis of the product solutions for Pd leachate and a correlation of the Pd leaching with product formation in the allylic substitution chemistry for both types of catalysts suggests that the active catalysts in these reactions are leached from the support. In the case of the allylic substitution reaction, external triphenylphosphine and substrate together are required for the chemistry and Pd leaching.
Palladium-Based Catalysts Supported by Unsymmetrical XYC–1 Type Pincer Ligands: C5 Arylation of Imidazoles and Synthesis of Octinoxate Utilizing the Mizoroki–Heck Reaction
Maji, Ankur,Singh, Ovender,Singh, Sain,Mohanty, Aurobinda,Maji, Pradip K.,Ghosh, Kaushik
, p. 1596 - 1611 (2020/04/29)
A series of new unsymmetrical (XYC–1 type) palladacycles (C1–C4) were designed and synthesized with simple anchoring ligands L1–4H (L1H = 2-((2-(4-methoxybenzylidene)-1-phenylhydrazinyl)methyl)pyridine, L2H = N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono)methyl)aniline, L3H = N,N-diethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono)methyl) aniline and L4H = 4-(4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono) methyl)phenyl)morpholine H = dissociable proton). Molecular structure of catalysts (C1–C4) were further established by single X-ray crystallographic studies. The catalytic performance of palladacycles (C1–C4) was explored with the direct Csp2–H arylation of imidazoles with aryl halide derivatives. These palladacycles were also applied for investigating of Mizoroki–Heck reactions with aryl halides and acrylate derivatives. During catalytic cycle in situ generated Pd(0) nanoparticles were characterized by XPS, SEM and TEM analysis and possible reaction pathways were proposed. The catalyst was employed as a pre-catalyst for the gram-scale synthesis of octinoxate, which is utilized as a UV-B sunscreen agent.
Bench-Stable and Recoverable Palladium(I) Dimer as an Efficient Catalyst for Heck Cross-Coupling
Sperger, Theresa,Stirner, Christopher K.,Schoenebeck, Franziska
supporting information, p. 115 - 120 (2016/12/24)
The application of air- and moisture-stable dinuclear palladium(I) complex [Pd(μ-I)(Pt-Bu3)]2 as an efficient catalyst for the Heck cross-coupling reaction of aryl iodides and bromides with acrylates and styrenes is described. The de
