Benzenedicarbonyl and benzenetricarbonyl linker pyrazolyl complexes of palladium(ii): synthesis, X-ray structures and evaluation as ethylene polymerisation catalystsElectronic supplementary information (ESI) available: molecular structures and bond lengths and angles for L2, L3, L6 and 2. See http://www.rsc.org/suppdata/dt/b2/b208376k/

Ethylene polymerization catalyzed by substituted pyrazole nickel complexes

“…4 shows the dependence of molecular weight on pressure. But generally polymer molecular weight distribution, measured by polydispersity indices, showed that they were approximately 2 and similar to distribution reported for other late-transition metal catalyzed ethylene polymerization [2][3][4][5][6][7][8][9][10].…”

“…In addition we also subsequently reported another class of palladium complexes, in which benzenedicarbonyl and benzenetricarbonyl linkers bridge pyrazolyl units [10]. These palladium complexes, with benzenecarbonyl linkers, are even better ethylene polymerization catalysts than the substituted pyrazole palladium complexes.…”

Palladium Complex Bearing 3,5-Bis(benzotriazol-1-Ylmethyl)toluene Ligand Catalyzes Oxidative Amination of Allyl Butyl Ether

“…Due to the insoluble nature of complex 2 in standard NMR solvents the proposed stoichiometry is mainly supported by elemental analysis and FT-IR spectra. Although mononuclear or binuclear complexes have been obtained using related bis(azolyl) ligands, 12,13,22 in our case the isolation of non-soluble material indicates the probable formation of a polymeric species with the ligand acting as N,N-bridge between two palladium centers. This assumption is supported by the presence of one band at 350 cm -1 in the infrared spectrum, assigned to the stretching frequency of the Pd-Cl bond, which is characteristic of a trans dichloride isomer.…”

“…[4][5][6][7][8] Another family of active late transition metal polymerization catalysts based on pyrazol and poly(pyrazolyl) ligands has been described. [9][10][11][12][13][14][15][16] These types of ligands are attractive since their steric and electronic properties can be changed by the appropriate selection of the substituents in the pyrazol ring.…”

Bis(3,5-dimethylpyrazol-1-yl)alkanones and their reactivity with [PdCl2(NCMe)2]: Isolation of bis(3,5-dimethylpyrazol-1-yl)propan-1-one palladium(II) chloride and C–H activation of propanone linker

“…Such linker binding atoms have allowed the design of tridentate chromium and nickel complexes that catalyze the polymerization or oligomerization of ethylene [6]. Recently we have used carbonylbenzene [7], carbonylpyridine [8], methylbenzene [9] and methylpyridine [10] linkers to prepare mainly bis(pyrazolyl)palladium complexes some of which catalyze oligomerization or polymerization of ethylene. For palladium complexes with pyridine-containing linkers the pyridine nitrogen binds in preference to one of the pyrazolyl units, thus leaving this pyrazolyl unit dangling; however bis(pyrazolylmethyl)pyridine ligands act a tridentate ligand when reacted with nickel(II) halides [11].…”