85744-68-9Relevant academic research and scientific papers
Influence of the phosphine arrangement on the reactivity of palladium(II) and platinum(II) polyphosphine complexes with copper(I) chloride
Fernández, Damián,García-Seijo, M. Inés,Sevillano, Paloma,Casti?eiras, Alfonso,García-Fernández, M. Esther
, p. 2527 - 2584 (2008/10/09)
The distorted square-planar complexes [Pd(PNHP)Cl]Cl (1) (PNHP = bis[2-(diphenylphosphino)ethyl]amine), [M(P3)Cl]Cl [P3 = bis[2-(diphenylphosphino)ethyl]phenylphosphine; M = Pd (2), Pt (3)] and [Pt(NP3)Cl]Cl (5) (NP3 = tris[2-(diphenylphosphino)ethyl] amine), coexisting in the later case with a square-pyramidal arrangement, react with one equivalent of CuCl to give the mononuclear heteroionic systems [M(L)Cl](CuCl2) [L = PNHP, M = Pd (1a); L = P3, M = Pd (2a), Pt (3a); L = NP3, M = Pt (5a)]. The crystal structure of 3a confirms that Pt(II) retains the distorted square-planar geometry of 3 in the cation with P3 acting as tridentate chelating ligand, the central P atom being trans to one chloride. The counter anion is a nearly linear dichlorocuprate(I) ion. However, the five-coordinate complexes [Pd(NP 3)Cl]Cl (4), [M(PP3)Cl]Cl (M = Pd (6), Pt (7); PP 3 = tris[2-(diphenylphosphino)ethyl] phosphine) containing three fused five-membered chelate rings undergo a ring-opening by interaction with one (4, 6, 7) and two (6, 7) equivalents of CuCl with formation of neutral MCu(L)Cl3 [L = NP3, M = Pd (4a); L = PP3, M = Pd (6a), Pt (7a)] and ionic [MCu(PP3)Cl2](CuCl 2) [M = Pd (6b), Pt (7b)] compounds, respectively. The heteronuclear systems were shown by 31P NMR to have structures where the phosphines are acting as tridentate chelating ligands to M(II) and monodentate bridging to Cu(I). Further additions of CuCl to the neutral species 6a and 7a in a 1:1 ratio resulted in the achievement of the ionic complexes 6b and 7b with CuCl2- ions as counter anions. It was demonstrated that the formation of heterobimetallic or just mononuclear mixed salt complexes was clearly influenced by the polyphosphine arrangement with the tripodal ligands giving the former compounds. However, complexes [M(NP3)Cl]Cl constitute one exception and the type of reaction undergone versus CuCl is a function of the d 8 metal centre.
Crystal structure and reactivity of mononuclear cationic palladium(II) and platinum(II) triphos complexes with phenyltin(IV) anions. The formation of polynuclear platinum-triphos ionic and covalent complexes
García-Seijo,Castieiras, Alfonso,Mahieu, Bernard,Jánosi, László,Berente, Zoltán,Kollár, László,García-Fernández
, p. 855 - 868 (2008/10/08)
The ionic complexes [M(triphos)Cl]X [M = Pd, X = Cl (1), SnCl3 (1a), SnPh2Cl3 (1c); M = Pt, X = Cl (3), SnCl3 (3a), SnPh2Cl3 (3c)], [M(triphos)Cl]2X [X = SnPh2Cl4, M = Pd (1b), Pt (3b); X = PtCl4, M = Pt (3d)] and [M(triphos)2]X2 [X = SnPh2Cl3, M = Pd (2), Pt (4)] where triphos = bis(2-diphenylphosphinoethyl)phenylphosphine, were synthesised and characterised by microanalysis, mass spectrometry, IR, 119Sn M?ssbauer, NMR (31P, 195Pt and 119Sn) spectroscopies and conductivity measurements. The X-ray crystal structures of compounds 1b, 3b and 3c, where tetrachlorodiphenylstannate(IV) and trichlorodiphenylstannate(IV) act as counterions stabilising cationic metal complexes, are reported. These compounds contain the cation [M(triphos)Cl]+ with distorted square-planar geometry at palladium or platinum, triphos acting as a tridentate chelating ligand. The anions [SnPh2Cl4]2- (1b, 3b) and [SnPh2Cl3]- (3c) have trans-octahedral and distorted trigonal-bipyramidal environments for the metal, respectively. Although the dinegatively charged [SnPh2Cl4]2- is counteracted by the presence of two singularly positively charged [M(triphos)Cl]+ species, interanion contacts via hydrogen bonds were found for 1b and 3b but were absent for compound 3c. The crystalline solids [M(triphos)2][SnPh2Cl3]2 M = Pd (2), Pt (4)] were formed via a chelate ring-opening reaction of [M(triphos)Cl]+ induced by triphos. The formation of heterometallic complexes by reaction of AgCl or Au(I) with the complex [Pt(triphos)2][SnPh2Cl3]2 (4), followed by 31P NMR in solution, did not take place. The presence of dangling arm phosphine oxide groups, on oxidation of complex 4 with H2O2, was detected. Other ring-opening reactions were observed by 31P NMR and conductivity measurements when solutions containing PtCl2(PhCN)2 and triphos in a molar ratio 3:2 were refluxed C6H6. Besides [Pt(triphos)Cl]2[PtCl4] (3d) and the ionic complex with a dinuclear anion, [Pt(triphos)Cl][Pt2(triphos)Cl5] (5), the covalent trinuclear complexes [{PtCl2(Ph2PCH2CH2) 2PPh-P1,P2}2(P3, P3)PtCl2] (6a, 6b) were formed as minor products. These latter diastereomeric species become the dominant species upon heating, being thermodynamically controlled complexes. Mixtures of 3d, 5, 6a and 6b converted to complex [Pt(triphos)Cl]Cl (3) by addition of triphos, chelate ring-closure reactions of 6a, 6b and the complex anion 5 occurring. With an excess of triphos (Pt:triphos = 3:4 or higher ratio), broad peaks reflecting fast equilibria between ring-opened and ring-closed products were found.
Influence on reactivity of chloro ligand substitution in mononuclear cationic Pd(II) and Pt(II) triphos complexes: X-ray structure of the nitrate derivatives
Fernández, Damián,Sevillano, Paloma,García-Seijo,Castieiras, Alfonso,Jánosi, László,Berente, Zoltán,Kollár, László,García-Fernández
, p. 40 - 52 (2008/10/08)
The substitution of chloro ligand in [M(triphos)Cl]Cl complexes [M = Pd (1), Pt (2); triphos = Ph2PC2H4P(Ph)C2H4 PPh2] by reaction with 1 equiv. of KX resulted in the formation of the ionic complexes [M(triphos)X]Cl [X = I, M = Pd (3), Pt (4); X = CN, M = Pd (5), Pt (6)]. Methanolic solutions of silver nitrate in excess displace the chloro ligand and counterion of 1 and 2, giving rise to the formation of the crystalline complexes [M(triphos)(ONO2)](NO3) [M = Pd (7), Pt (8)] suitable for X-ray diffraction studies. The complexes show a distorted square-planar environment around the metal, there being three coordination sites occupied by phosphorus atoms from the triphos and the fourth by the oxygen atom from a nitrate acting as monodentate ligand. A second NO3- is acting as counterion with D3h symmetry. The use of a high excess of SnCl2 in the presence of 1 equiv. of PPh3 enabled the formation of complexes [M(triphos)(PPh3)](SnCl3)2 [M = Pd (9), Pt (10)]. These complexes, in addition to [M(triphos)X]X [X = Br, M = Pd (1a), Pt (2a); X = I, M = Pd (1b), Pt (2b)], were synthesised and all Pt(II) complexes characterised by microanalysis. Mass spectrometry, IR spectroscopy, NMR spectroscopy and conductivity measurements were also used for characterisation. The structure and reactivity studies in solution were carried out by 31P{1H} NMR. The trends in chemical shifts δ (P) and 1J(195Pt,31P) coupling constants were used to establish a sequence in the X ligand exchange reactions. While [Pd(triphos)I]I (1b) undergoes a ring-opening reaction by titration with AuI, the analogous Pt(II) complex (2b) does not react. The formation of new five-coordinate Pd(II) and Pt(II) complexes was observed by titration of 5-8 with potassium cyanide.
Gold(I)-induced chelate ring-opening of palladium(II) and platinum(II) triphos complexes
Sevillano, Paloma,Habtemariam, Abraha,Parsons, Simon,Castineiras, Alfonso,Garcia, M. Esther,Sadler, Peter J.
, p. 2861 - 2870 (2007/10/03)
The complexes [M(triphos)Cl]Cl [triphos = PhP(CH2CH2PPh2)2; M = Pd (1), M = Pt (2)] undergo ring-opening reactions with AU(I) to give [MAu(triphos)Cl3] [M = Pd (3), M = Pt (4)]. In these mixed metal c
Chelate ring-opening of Pd(II) triphos complexes: Ligand exchange, selective phosphine oxidation, and X-ray crystal structure of [Pd(Ph2P(CH2)2PPh(CH2) 2P(O)Ph2)2Br]Br
Sevillano, Paloma,Habtemariam, Abraha,Castineiras, Alfonso,Esther Garcia,Sadler, Peter J.
, p. 383 - 389 (2008/10/08)
31P NMR studies show that chelate ring-opening of [Pd(triphos)Cl]+ , 4, (triphos = Ph2P(CH2)2PPh(CH2) 2PPh2) can be achieved in solution by reaction with excess of triphos with the formation of [Pd(Ph2P(CH2)2PPh(CH2)2PPh 2-P,P)2]2+. In the X-ray crystal structure, [Pd(triphos)Br]Br, 1 has a distorted square-planar geometry, and the oxidation of 1 with H2O2 gives rise to [Pd(Ph2P(CH2)2PPh(CH2) 2P(O)Ph2-P,P)2]2+, 2, which contains two bidentate ligands. The presence of two dangling arm phosphine oxide groups was confirmed by X-ray crystallography for the related complex [Pd(Ph2P(CH2)2PPh(CH2) 2P(O)Ph2-P,P)2Br]Br, 3, which contained square-pyramidal five-coordinated Pd(II).
