106500-79-2Relevant academic research and scientific papers
Transition-metal derivatives of the cyclopentadienylphosphine ligands. 7. Electrochemical oxidation of [Rh(μ-C5H4PPh2)(CO)]2 and rereduction: An ECE process including a fast reversible configurational switch
Tommasino, Jean-Bernard,De Montauzon, Dominique,He, Xiadong,Maisonnat, André,Poilblanc, René,Verpeaux, Jean-Noel,Amatore, Christian
, p. 4150 - 4156 (2008/10/08)
The electrochemical oxidation of the cyclopentadienylphosphine-bridged complex [Rh(μ-C5-H4PPh2)(CO)]2 and the reduction of the dicationic parent compound [Rh(μ-C5H4PPh2)(CO)]2 2+ have been performed at various scan rates from 0.1 to 1200 V·s-1 using ultramicroelectrodes. The analysis of the voltammograms and their digital simulation reveal an ECE process where the intervening chemical step is a very fast reversible conformational change (k1 = 4000 s-1; k-1 = 2000 s-1) involving two monocationic intermediates assumed to be respectively a non-metal-metal-bonded mixed-valence complex and a metal-metal-bonded complex (with a bond order closed to 0.5). The high rates of this conformational change, pictured as a disrotatory deformation of the (μ-C5H4PPh2)2 central unit, point out to an interesting specificity of this bridging ligand.
Transition-metal derivatives of the cyclopentadienyl phosphine ligands. 3. New pathways to polymetallic complexes
He, Xiao Dong,Maisonnat, André,Dahan, Fran?oise,Poilblanc, René
, p. 2618 - 2626 (2008/10/08)
A series of new derivatives of heterodifunctional ligands have been synthesized starting from lithium (diphenylphosphino)- or ((diphenylphosphino)ethyl)cyclopentadienide and from ((diphenylphosphino)-cyclopentadienyl)- or ((dimethylphosphino)cyclopentadienyl)thallium. These are monometallic (1,2, and 4) and heterobimetallic molybdenum(0), tungsten(0), iridium(I), and iridium(I) complexes (3) together with dissymmetric (5) and symmetric (6) homobimetallic rhodium(I) and iridium(I) complexes. They have been fully characterized by their spectroscopic data (including phosphorus-rhodium and phosphorus-tungsten coupling constant measurements) and by electron-impact mass spectroscopy. Interestingly, the synthesis of the bimetallic compounds involves a novel pathway beginning with steps of coordination of the phosphorus extremity of the bifunctional ligands. Of special interest are the compounds L2Rh(η5-C5H4)Ph 2PRhCl(PPh3)L (5), which associate one 18-electron and one 16-electron site, and the compounds [M(η5-C5H4)PR2(CO)]2 (M = Rh, Ir; R = Ph, Me) (6), which associate two 18-electron sites. Complex 6a (M = Rh; R = Ph) crystallizes in the triclinic space group P1 with one molecule in the unit cell of dimensions a = 9.475 (1) A?, b = 9.527 (1) A?, c = 9.145 (1) A?, α = 99.80 (1) A?, β = 109.86 (1)°, γ = 90.36 (1)°, and V = 763.2 (3) A?3. Least-squares refinement leads to a value of 0.032 for the conventional R index for 2938 reflections having I > 3σ(I). The dinuclear molecule consists of two "Rh(CO)" moieties bridged by two (diphenylphosphino) cyclopentadienyl ligands that are in a mutual head-to-tail arrangement, and the large Rh-Rh separation, 4.3029 (6) A?, precludes any metal-metal interaction.
(Dimethylphosphino)- and (diphenylphosphino)cyclopentadienyl derivatives of cobalt, rhodium, and iridium: The crystal and molecular structure of dicarbonyl{μ-[(η5-cyclopentadienyl)dimethylphosphine-P]}-dirhodium
Rausch, Marvin D.,Spink, W. Craig,Atwood, Jerry L.,Baskar, Andrew J.,Bott, Simon G.
, p. 2627 - 2631 (2008/10/08)
The reaction of cyclopentadienylthallium with chlorodimethylphosphine followed by thallium ethoxide has produced [(dimethylphosphino)cyclopentadienyl]thallium (3) in 80% yield. Reactions of 3 as well as its diphenyl analogue (2) with group 9 metal carbonyl halides afford new homobimetallic complexes [M(η5-C5H4)PR2(CO)]2 (M = Co, Rh, Ir; R = CH3, C6H5) (4, 7-10) in good to excellent yields. These complexes possess novel cyclic, dimeric structures. The product from the reaction of 3 with [Rh(CO)2Cl]2 (9) has been characterized by means of a single-crystal X-ray diffraction study. 9 crystallizes in the triclinic space group P1 with a = 7.188 (6), b = 7.725 (6), c = 8.675 (3) A?, α = 102.34 (5)°, β = 96.26 (5), and γ = 102.05 °. The final R value based on 1528 observed reflections was 0.036. The dimer resides on a crystallographic center of inversion. The Rh-C(η5) lengths range from 2.232 (7) to 2.303 (8) A?, and the Rh-P length is 2.233 (2) A?.
Synthesis and characterization of new rhodium and iridium complexes containing the heterodifunctional ligand (diphenylphosphino)cyclopentadienyl
He, XiaoDong,Maisonnat, André,Dahan, Fran?oise,Poilblanc, René
, p. 678 - 680 (2008/10/08)
The new complexes (η5-C5H4)PPh2M(CO)(PPh 3) (1a, M = Rh; 1b, M = Ir), [(η5-C5H4FPh2]2M 2(CO)2 (2a, M = Rh; 2b, M = Ir), and IrCl(CO)Ph2P(η5-C5H 4)Ir(CO)(PPh3)2 (3b) have been prepared and characterized. In the mononuclear complexes 1a and 1b, the heterodifunctional ligand possesses a free phosphine group that may attach to a second metal center as illustrated by the conversion of 1a into the dinuclear complex 2a. Complexes 2a and 2b have dinuclear symmetrical structures where the metallic centers are linked by two bridging (diphenylphosphino)cyclopentadienyl ligands in a head-to-tail configuration.
