113379-50-3Relevant academic research and scientific papers
A quasi-covalent metal-metal bond in an early-late heterobimetallic Ti-Pt complex stabilized by phosphinoenolate ligands
Braunstein, Pierre,Morise, Xavier,Benard, Marc,Rohmer, Marie-Madeleine,Welter, Richard
, p. 610 - 611 (2003)
An unusual early-late bimetallic complex with direct metal-metal bonding is obtained from a phosphinoenolate ligand-assisted reaction between Ti(IV) and Pt(0) reagents which occurs by formal insertion of the Pt(0) centre into a Ti(IV)-O bond; X-ray data and EHMO calculations indicate the presence of a quasi-covalent Ti(III)-Pt(I) bond (2.721(2) A).
Synthesis and reactivity of aryl- and alkyl-palladium(II) complexes with functional phosphines and phosphinoenolate ligands: First analogues of model nickel catalysts
Andrieu, Jacques,Braunstein, Pierre,Naud, Frederic
, p. 2903 - 2909 (2007/10/03)
Phenyl- and methyl-palladium(II) complexes analogous to model nickel(II) catalysts were prepared from readily available precursors. The methods used allow different ligands to be introduced in the co-ordination sphere. For example, the chelating phosphinoenolate ligand in [PdPh{Ph2PCH-..C(-..O)NPh2}L 2] [L2 = Ph2PCH2C(O)NPh2] was displaced by 1 equivalent of Ph2PCH2C(O)Ph(L1) to give [PdPh{Ph2PCH-..C(-..O)Ph}L2] whereas the terminal functional phosphine was displaced by P(C6H11)3 to give [PdPh{Ph2PCH-..C(-..O)NPh2}{P(C 6H11)3}]. Owing to favourable ligand-redistribution reactions, treatment of a mixture of complexes trans-[PdMe(Cl)L22], trans-[PdMe(Cl)L12] and trans-[PdMe(Cl)L1(L2)] (which cannot be isolated pure) with an excess of NaOMe in toluene selectively afforded the phosphinoenolate complex [PdMe{Ph2PCH-..C(-..)Ph}L2]. The enolate moiety of [PdPh{Ph2PCH-..C(-..O)NPh2}L 2] and of [PdMe{Ph2PCH-..C(-..O)NPh2}L 2] reacted with R′N=C=O (R′ = Ph or p-tolyl) with formation of a carbon-carbon bond in a Michael-type addition and the products were shown to exist in the form of two isomers a and b, characterised by a N-H ... O or a N-H ... N hydrogen bond within the ligand system. Insertion of CO into the Pd-Me bond of [PdMe{Ph2PCH-..C(-..O)NPh2}L 2] or [PdMe{Ph2C[=C(O)NHPh]C(O)NPh2}L2] yielded the corresponding acyl complexes. Although [PdMe{Ph2PCH-..C(-..O)Ph}(PPh3)] inserted ethylene into its Pd-Me bond, as evidenced by quantitative formation of propylene, the palladium hydride that must be generated by the β-elimination reaction decomposes before further ethylene insertion can occur.
Complexes of Functional Phosphines. Part 11. β-Ketophosphine Complexes of Nickel, Palladium, and Platinum. Crystal Structures of trans-
Braunstein, Pierre,Matt, Dominique,Nobel, Dominique,Balegroune, Fadila,Bouaoud, Salah-Eddine,et al.
, p. 353 - 362 (2007/10/02)
The synthesis and spectroscopic properties (1H and 31P n.m.r., i.r.) of complexes containing the β-ketophosphine Ph2PCH2C(O)Ph (HL) are described.In , (4), (5), and 2> (6), HL behaves as a P-bonded monodentate ligand whereas in the cationic complexes 2 and 2>2 it acts as a P, O chelate.The crystal structures of (1) and (3) have been determined using single-crystal X-ray diffraction methods.Compound (1) crystallises in space group P21/n, with a=10.079(3), b=11.510(3), c=15.411(3) Angstroem, β=93.42(2) deg, and Z=2.Compoumd (3) crystallises in space group P21/c, with a=9.283(1), b=10.261(1), c=19.318(1) Angstroem, β=96.20(1) deg, and Z=2.The structures have been refined to R 0.050 (R' 0.060) for (1) and to R 0.032 (R' 0.041) for (3).The geometries of these complexes are essentially identical although the ν(CO) frequencies of these complexes are significantly different -1 for (1) and 1 620 cm-1 for (3)>; the nickel atom occupies a centre of symmetry and has thus a square-planar environment.Although the ketone group is bent towards the nickel atom, no significant Ni-O bonding interaction occurs, as deduced from the Ni-O distances .In refluxing toluene (1), (4), or (5) lead to the phosphine-phosphinite complexes cis- (M=Ni, Pd, or Pt).Treatment of (1), (4), or (5) with base gives the enolato-complexes cis- (M=Ni, Pd, or Pt).Reaction of (6) with NaH affords the binuclear complex .The latter reacts with PPh3 to give cis-, and with Ph2PCH2CH2PPh2-TIPF6 to give .The P-O coupling products (R=Cl or Ph) are obtained by reaction of the complex with PCl3 and PPhCl2 respectively, and shown to have a five-co-ordinate structure.The square-planar P,P,P complex results from reaction of with TIPF6.
Complexes of functional phosphines. 10. Palladium complexes with the ligands Ph2PCH2COPh, (Ph2PCHCOPh)-, and Ph2PCHC(Ph)OPPh2. Crystal and molecular structure of cis-[PdCl2{Ph2PCHC(Ph)OPPh2}]
Bouaoud, Salah-Eddine,Braunstein, Pierre,Grandjean, Daniel,Matt, Dominique,Nobel, Dominique
, p. 3765 - 3770 (2008/10/08)
(Diphenylphosphino)acetophenone, Ph2PCH2COPh (L), was synthesized by reacting Ph2PCl with PhCOCH2Li in THF. In the complexes [PdCl2L2] (1), [(η3-C4H7)PdClL] (2), [(o-C6H4CH2NMe2)PdClL] (3), [(C10H8N)PdClL] (4), and [(C14H13N2)-PdClL] (5), L behaves as a monodentate ligand (through phosphorus), and in [(o-C6H4CH2NMe2)Pd{Ph 2PCH2C(O)Ph}]-[CF3SO3] (6), [(C10H8N)Pd{Ph2PCH2C(O)Ph}][CF 3SO3] (7), and [(C14H13N2)Pd{Ph2PCH 2C(O)Ph}][CF3SO3] (8), L behaves as a chelating ligand (through phosphorus and the keto group). Treatment of 3-5 with NaH in THF led to the corresponding enolato-phosphine complexes 9-11, in which the P,O-chelate ligand behaves as a three-electron donor. Reaction of Li2PdCl4 with 2 equiv of L in the presence of NEt3 afforded cis-[Pd{Ph2PCHC(O)Ph}2] (12). Thermolysis of 1 in toluene resulted in the quantitative formation of cis-[PdCl2{Ph2PCHC(Ph)OPPh2}] (13). The molecular structure of 13 has been determined by X-ray diffraction: monoclinic, space group P21/c, with Z = 4, a = 10.602 (6) A?, b = 19.503 (4) A?, c = 14.631 (9) A?, β = 97.27(3)°, and d(calcd) = 1.476 g/cm3. The structure was solved by using 2780 reflections with Fo2 ≥ 3σ(Fo2) and refined to conventional R = 0.038, Rw = 0.049. The coordination around Pd is square planar, with Cl(1)-Pd-Cl(2) and P(1)-Pd-P(2) angles of 91.77 (6) and 92.88 (6)°, respectively. The puckering of the six-membered ring is accompanied by a large P(1)-O(1)-C(14) angle of 131.1 (4)°. All complexes were characterized by elemental analyses and IR, 1H NMR, and 31P[1H] NMR spectroscopy.
