65097-96-3Relevant articles and documents
Thiosaccharinate binding to palladium(II) and platinum(II): Synthesis and molecular structures of sulfur-bound complexes [M(κ1-tsac) 2(κ2-diphosphane)]
Al-Jibori, Subhi A.,Al-Jibori, Mohamed H.S.,Hogarth, Graeme
, p. 117 - 123 (2013/05/22)
Palladium(II) and platinum(II) thiosaccharinate complexes [M(κ1-tsac)2{κ2-Ph 2P(CH2)nPPh2}] (M = Pd, Pt; n = 1-4) have been prepared, palladium complexes from reaction of [Pd(tsac) 2]·H2O with diphosphanes and platinum complexes from addition of thiosaccharin to [PtCl2{κ2-Ph 2P(CH2)nPPh2}] in the presence of triethylamine. All complexes have been fully characterized and the crystal structures of [Pd(κ1-tsac)2(κ2- dppp)] (n = 3) and [Pt(κ1-tsac)2(κ 2-dppm)] (n = 1) have been determined confirming that thiosaccharinate ligands are S-bound. The larger ring complexes (n = 3, 4) are fluxional in solution being attributed to the conformational flexibility of the diphosphane backbones The bis(diphosphane) complexes, [M(κ1- tsac)2(κ1-dppm)2] (M = Pd, Pt), have also been prepared upon treatment of [Pd(tsac)2]·H2O with two equivalents of dppm or addition of thiosaccharin to [Pt(κ2-dppm)2]Cl2 in the presence of triethylamine in which the diphosphanes bind in a monodentate fashion. Both are highly fluxional in solution, changes in the 31P{1H} NMR spectra as a function of temperature being interpreted as the exchange of bound and unbound phosphorus atoms.
Mechanistic insight into the protonolysis of the Pt-C bond as a model for C-H bond activation by platinum(II) complexes
Romeo, Raffaello,D'Amico, Giuseppina
, p. 3435 - 3446 (2008/10/09)
The kinetic and NMR features of the protonolysis reactions on platinum(II) alkyl complexes of the types cis-[PtMe2L2], [PtMe 2(L-L)], cis-[PtMeClL2], and [PtMeCl(L-L)] (L = PEt 3, P(Pri)3, PCy3, P(4-MePh) 3, L-L = dppm, dppe, dppp, dppb) in methanol suggest a rate-determining proton attack at the Pt - C bond. In contrast, a multistep oxidative-addition - reductive-elimination mechanism characterizes the methane loss on protonation of the corresponding trans-[PtMeClL2] species. Tools that were particularly diagnostic in suggesting different reaction pathways for the two systems were (i) the different results of kinetic deuterium isotope experiments, (ii) the detection or absence of Pt(IV) hydrido alkyl intermediate species by low-temperature 1H NMR experiments, and (iii) the detection or absence of isotope scrambling and incorporation of deuterium into Pt - CH3, combined with the loss of a range of CH nDn-4 isotopomers. For all systems, the rates of protonolysis are retarded by ligand steric congestion, accelerated by ligand electron donation, and almost unaffected by the chain length along the series of chelate complexes. A straight line correlates the rates of protonolysis of cis-dialkyl and cis-monoalkyl complexes, the difference in reactivity between the two systems being almost 5 orders of magnitude (slope of the line = 6 × 104). Factors controlling the dichotomy of behavior between complexes of different geometry have been taken into consideration. Application of the principle of microscopic reversibility suggests the reason why platinum complexes with nitrogen donor ligands appear to be far more efficient than platinum phosphane complexes in activating the C-H bond.
Stability of (Chloromethyl)platinum(II) Complexes
McCrindle, Robert,Arsenault, Gilles J.,Gupta, Anuradha,Hampden-Smith, Mark J.,Rice, Richard E.,McAlees, Alan J.
, p. 949 - 954 (2007/10/02)
The stabilities of , (cod = cycloocta-1,5-diene) and a range of phosphine-containing mono- and cis-bis-(chloromethyl)platinum(II) complexes have been investigated in deuteriochloroform at room temperature.Some of the bis(chloromethyl) derivatives appear to be indefinitely stable (cod and chelating arylphosphines), others suffer very slow decomposition to the dichlorides (non-chelating arylphosphines), and the remainder decompose relatively rapidly, and cleanly, to the dichlorides plus ethylene (alkylphosphines, non-chelating faster than chelating).Rapid decomposition of the arylphosphine complexes can be induced by adding hexafluoroisopropyl alcohol to the deuteriochloroform solutions.Attempts to generate 2> by addition of P(C6H11)3 to resulted in the formation of cis--+(C6H11)3>Cl2>; a mechanism is proposed.All cis-mono(chloromethyl) derivatives studied appear to be indefinitely stable.In contrast, the trans-mono(chloromethyl) complexes, although stable in very dry solvent, undergo decomposition in the presence of moisture to the corresponding hydrides plus formaldehyde; a mechanism is proposed.The hydrides undergo subsequent conversion into a mixture of cis and trans dichlorides.
