Search results for "PALLADIUM"

Dinuclear palladium(ii) compounds with bridging cyclometalated phosphines. Synthesis, crystal structure and electrochemical study

2006

The structural characterization of bis-cyclometalated palladium(II) compounds of formula Pd2[(micro-(C6X4)PPh2]2(micro-O2CR)2 [X = H, R = CH3 (3), CF3 (4), C(CH3)3 (5) and C6F5 (6); X = F, R = CH3 (7) and CF3 (8)], has confirmed its paddle wheel structure with two palladium atoms bridged by two acetates and two metalated phosphines in a head-to-tail arrangement. The Pd...Pd distances are in the range 2.6779(16)-2.7229(8) A. Under cyclic voltammetric conditions, compounds 3-6, in CH2Cl2 solution, were found to undergo a reversible oxidation peak in the range of potential values 0.84-1.25 V. A second partially-reversible oxidation is observed at more positive potentials (1.37-1.55 V). For com…

Hexaphosphine: A Multifaceted Ligand for Transition Metal Coordination

2011

We report the synthesis and characterization of the first ferrocenyl polyphosphane incorporating six phosphorus donor atoms. In this unique ligand, the cyclopentadienyl rings of the ferrocenyl backbone adopt a staggered position, which leads to a piano-stool arrangement for each of the two sets of three P atoms facing the same direction. As a consequence of its remarkable flexibility, this hexaphosphane displays versatile coordination behaviour towards metals, leading to unexpected structures of palladium and platinum bimetallic complexes. Analogous molybdenum and rhodium complexes are more classical.

New Di- and Trinuclear Complexes with Pyrazolato Bridges. Crystal Structures of [{(C6F5)2Pd(μ-pz)(μ-Cl)}2Pd]2– and [(C6F5)2Pd(μ-pz)2Pd(η3-C4H7)] (pz …

2000

Benzoato and Thiobenzoato Ligands in the Synthesis of Dinuclear Palladium(III) and ‐(II) Compounds: Stability and Catalytic Applications

2015

New palladium(III) compounds of formula Pd2[(C6H4)PPh2]2[OXC(C6H5)]2Cl2 [3a (X = O); 3b (X = S)] were obtained by the oxidation of the analogous palladium(II) ones with PhICl2 and were characterized by 31P, 1H, and 13C NMR spectroscopy at 223 K. Compound 3a was also structurally characterized by single-crystal X-ray diffraction methods, which revealed a Pd–Pd distance of 2.5212(10) A. DFT calculations were conducted to study the stability of all of these new palladium(III) and -(II) compounds with focus on the influence of the OS substitution of the donor atom in the ligand. The palladium(II) compounds Pd2[(C6H4)PPh2]2[OXC(C6H5)]2 [2a (X = O), 2b (X = S)] were also tested as precatalyst in …

Chiral Self‐Sorting of trans ‐Chelating Chiral Ligands upon Formation of Pd II Complexes (Eur. J. Inorg. Chem. 15/2014)

2014

Chiral Self-Sorting of trans-Chelating Chiral Ligands upon Formation of PdII Complexes

2014

Invited for the cover of this issue is the group of Arne Lutzen at the University of Bonn, Germany. The cover image shows two dissymmetric bis(3-pyridyl) ligands based on a planar chiral pseudo-ortho-disubstituted [2.2]paracyclophane scaffold. Upon forming a mononuclear [ML2] complex with palladium(II) ions, these ligands act in a trans-chelating manner and undergo complete chiral self-sorting.

Palladium-Based Metal Organic Frameworks as Heterogeneous Catalysts for C-C Couplings

2022

Among the various cross coupling reactions, C−C cross coupling reaction has attracted many researchers to investigate in the last four decades. The continuous, constant, and consistent progress in this field fetched a Noble prize in 2010, showing the importance of this reaction in diversified fields. Among the various transition metals studied for this reaction, Pd is one of the metals that has exhibited the highest activity due to its unique features and reactivity. Although Pd-based homogeneous catalyst was the preferred choice for many researchers, the field slowly diverted towards the development of Pd-based heterogeneous catalysts for C−C coupling reactions. This is obviously due to th…

Synthesis and Reactivity of Ortho-Mercuriated and Ortho-Palladated Arylacetals and Cyclic and Acyclic Aryldithioacetals. New Examples of the Rearrang…

2004

The arylmercurial [Hg{C6H3(CHO)2-2,5}Cl] (1) reacts with CH(OMe)3 or HS(CH2)2SH to give [Hg{C6H3{CH(OMe)2}2-2,5}Cl] (2) or [Hg(Ara)Cl] [Ara = C6H3{CH(SCH2CH2S)}2-2,5 (3a)], respectively. The mercur...

Synthesis and characterization of new oxazoline-based palladacycles with bridging or terminal imidate ligands. Crystal structures of [{Pd(μ-dibromoma…

2008

Abstract The dinuclear hydroxo complex [{Pd(μ-OH)(Phox)}2] (I) (Phox = 2-(2-oxazolinyl)phenyl) reacts in a 1:2 molar ratio with several imidate ligands to yield new cyclometallated palladium complexes [{Pd(μ-NCO)(Phox)}2] containing asymmetric imidate –NCO– bridging units. [–NCO– = succinimidate (succ) (1), phtalimidate (phtal) (2), maleimidate (mal) (3), 2,3-dibromomaleimidate (2,3-diBrmal) (4) and glutarimidate (glut) (5)]. The reaction of these complexes with tertiary phosphines provides novel mononuclear N-bonded imidate derivatives of the general formula [Pd(imidate)(Phox)(PR3)] [R = Ph (a), 4-F–C6H4 (b) or CH2CH2CN (c)]. The new complexes were characterized by partial elemental analys…

Synthesis and X-ray Crystallographic Characterization of (μ-(Diphenylphosphino)phenyl-C2,P)palladium Bromide. A Novel Tetranuclear Metalated Compound

1997

The synthesis and crystal structure of a tetranuclear palladium cluster, [Pd(PC)Br]4 (PC) = [P(C6H4)Ph2]-), is described. Cleavage of this cluster with phosphines yields the mononuclear species Pd(PC)Br(P) in the form of cis and trans isomers. An equilibrium between mono- and tetranuclear species is observed for P = PCBr.