37523-60-7Relevant academic research and scientific papers
Synthesis and oxidation reactions of the unsaturated anion [Mn2(CO)6(μ-Ph2PCH2 PPh2)]2-
Liu, Xiang-Yang,Riera, Victor,Ruiz, Miguel A.,Bois, Claudette
, p. 3007 - 3016 (2008/10/08)
Chemical reduction of the unsaturated dihydride [Mn2(μ-H)2(CO)6(μ-dppm)] (dppm = Ph2PCH2PPh2) with several reagents (Na-Hg, K, etc.) promotes dihydrogen elimination to yield the deep green
dppm-assisted synthesis and reactivity of bimetallic M-Mo, M-W, M-Co, and M-Mn (M = Pt, Pd) complexes. Crystal structure of [(η2-dppm)Pt(μ-dppm)W(CO)2Cp][PF 6]·CH2Cl2 (dppm = Ph2PCH2PPh2)
Braunstein, Pierre,De Méric De Bellefon, Claude,Oswald, Beno?t,Ries, Michel,Lanfranchi, Maurizio,Tiripicchio, Antonio
, p. 1638 - 1648 (2008/10/08)
Heterometallic carbonyl complexes and clusters were prepared by reaction of dppm (dppm = Ph2PCH2PPh2) with linear trinuclear chain complexes trans-[Pt(or Pd){m(CO)}2(NCPh)2] (m(CO) = Mo(CO)3Cp, W(CO)3Cp, Mn-(CO)5, Co(CO)4). The reaction of trans-[Pd{m(CO)}2(NCPh)2] with dppm afforded products having very different structures depending on the nature of the metal carbonyl fragment m(CO), as exemplified by the synthesis of the cationic bimetallic complexes [Pd(μ-dppm)2m]+ (m = Mo(CO)2Cp, 1+;m = W(CO)2Cp, 2+), the neutral bimetallic [ClPd(μ-dppm)2Mn(CO)3] (3a), and the trinuclear cluster [PdCo2(CO)5(μ-dppm)2] (6). In contrast, the reaction of the Pt precursor trans-[Pt{m(CO)}2(NCPh)2] with dppm is much more selective, giving only bimetallic ionic complexes [(η2-dppm)Pt(μ-dppm)m][m(CO)] (m = Mo(CO)2Cp, 7a; m = W(CO)2Cp, 8a; m = Mn(CO)4, 9; m = Co(CO)3, 10). Exchange of the anions in 7a and 8a with PF6- afforded [(η2-dppm)Pt(μ-dppm)Mo(CO)2Cp]-[PF6] (7b) and [η2-dppm)Pt(μ-dppm)W(CO)2Cp] [PF6] (8b), respectively, which are more soluble. The solid-state structure of the dichloromethane solvate of 8b has been determined by a single-crystal X-ray analysis. It crystallizes in the triclinic space group P1 with Z = 1 in a unit cell of dimensions a = 11.257(7) A?, * = 12.691(6) A?, c = 11.055(6) A?, α = 112.20(3)°, β = 101.68(3)°, and γ = 76.71(4)°. The structure has been solved from diffractometer data by Patterson and Fourier methods and refined by full-matrix least squares on the basis of 5157 observed reflections to R and Rw values of 0.0372 and 0.0494, respectively. In the structure of the chiral cation of 8b, a dppm chelates the Pt atom and the other bridges the W and Pt metals, which are linked by a rather long metal-metal bond [2.902(2) A?]. Compounds 7b and 8b react with NaBH4 to give the hydrido complexes [(η1-dppm)(H)Pt(μ-dppm)m] (m = Mo(CO)2Cp, 11; m = W(CO)2Cp, 12) in which the hydride ligand occupies a position trans to phosphorus. The situation is different for [(η1-dppm)(H)Pt(μ-dppm)Co(CO)3] (13), obtained from 10, in which the hydride ligand is cis to the Pt-bound phosphorus atoms. The structures of all these complexes are consistent with the IR and 1H, 31P, and 195Pt spectroscopic data.
Synthesis and reactivity of Pd2Mn, MPdFe, MPdMn2, and MPdFe2 clusters (M = Pd, Pt) stabilized by Ph2PCH2PPh2 (dppm) ligands. Crystal structure of [Pd2Mn2(μ3-CO)(μ-CO)(CO) 7(μ-dppm)2]
Braunstein, Pierre,De Bellefon, Claude De Méric,Ries, Michel,Fischer, Jean
, p. 332 - 343 (2008/10/08)
Heterotetranuclear dppm-stabilized metalloligated clusters have been prepared by reaction of [Fe(CO)3NO]- or [Mn(CO)5]- with the dinuclear d9-d9 complexes [PdMCl2(μ-dppm)2] (M = Pd, Pt). These clusters, of formula [PdMFe2(CO)5(NO)2(μ-dppm)2] (M = Pd, 1a; M = Pt, 1b) and [PdMMn2(CO)9(μ-dppm)2] (M = Pd, 4a; M = Pt, 4b), are characterized by an almost planar metal core, whose Pd-M, M-Fe, and M-Mn edges are bridged by a dppm ligand. The metalloligand Fe(CO)3NO or Mn(CO)5 is always connected to the triangular core PdMFe or PdMMn, respectively, via a Pd atom. This was established by an X-ray diffraction study on 4a: monoclinic, space group P21/c, with Z = 4, a = 17.561 (7) A?, b = 21.319 (8) A?, c = 19.461 (8) A?, β = 113.50 (2)°, and d(calcd) = 1.44 g/cm3. The structure was solved by using 4473 reflections with I > 3σ(I) and refined to conventional R = 0.059 and Rw = 0.082. The Pd(2)-Mn(1) distance (2.580 (2) A?) is shorter than the Pd(1)-Mn(1) distance (2.698 (2) A?) and the exocyclic, unsupported Pd(1)-Mn(2) distance (2.821 (2) A?). The Pd(1)-Pd(2) distance is 2.681 (1) A?. Whereas the coordination about Mn(2) is octahedral, that about Mn(1) can be viewed as highly distorted octahedral. These clusters result from the formal insertion of a Fe(CO)2NO or Mn(CO)4 fragment into the Pd-P bond of the dinuclear precursor. This accounts for the complete regioselective formation of the platinum-containing clusters in which the less labile Pt-P bonds have been retained. The chemistry reported here for the dinuclear MPdP4 and for the MPdFe2P4 or MPdMn2P4 systems takes place within their plane, in contrast to the chemistry leading to A-frame structures. Furthermore, the exocyclic Pd-Fe or Pd-Mn bond of 1 or 4, respectively, is very labile and may be broken sometimes reversibly in dissociating solvents or by other nucleophiles, e.g., halides. Whereas clusters 1 do not react with CO, [PdMFeI(CO)2(NO)(μ-dppm)2] affords cationic clusters in the presence of Tl[PF6], which are characterized by a Pd-bound terminal CO. An effect of platinum that renders its neighboring palladium center more electron-rich is noted and influences the reactivity of the clusters. The Mn-containing clusters are generally more labile than their Fe analogues, and 4b slowly rearranges in solution with formation of the binuclear cation [(OC)4Mn(μ-dppm)Pt(dppm)]+. All complexes were characterized by elemental analyses and IR, 1H NMR, and 31P{1H} NMR spectroscopies. The latter is particularly informative because of the inequivalence of the four phosphorus atoms, and comparisons are made between related systems.
