Formation of PPh₂C₆F₅ through Phosphido Platinum and/or Palladium(III) Intermediates^,

Abstract

The two-electron oxidation reactions of the neutral [(C6F5)2M(μ-PR2)2M‘(NCCH3)2] (M = M‘ = Pt or Pd, M = Pt, M‘ = Pd) complexes using I2 as oxidant have been investigated by experimental (R = Ph) and electronic structure calculation methods (R = H). It was found that a reductive coupling of PR2 and C6F5 takes place along the reaction pathway for all oxidized complexes. The most salient structural features of the [(C6F5)2Pt(μ-PR2)2Pd(C6F5)2]2-, [(C6F5)2Pd(μ-PR2)2Pd(acac)]-, and [(C6F5)2Pt(μ-PR2)2PtI2] complexes (experimental R = Ph) are reproduced very well by the B3LYP/lanl2dz calculations (R = H).

Chemoselectivity control in the reaction of a dinuclear chloro-bridged cyclopalladated complex with potassium diphenylphosphide

“…The Pd(III)e Pd(III) P-containing intermediates are expected to give 31 P NMR signals in a very low field (cf. data for compounds VIII, Chart 1) [25]. No signals above 130 ppm were observed in the 31 P NMR spectra of the studied reactions.…”

An organometallic tetranuclear cluster with phosphine and phosphido ligands in nonclassical bonding modes: X-ray structural characterization

“…We have recently reported a straightforward method for the synthesis of the heterodinuclear complex [(C 6 F 5 ) 2 Pt(lPPh 2 ) 2 Pd(NCCH 3 ) 2 ] (3) [3], as a yellow solid and studied some reactions of this complex. We observed that CH 2 Cl 2 solutions of 3 at room temperature became dark in colour and, after work up of the mixture, a purple solid was isolated.…”

“…Complexes [(C 6 F 5 ) 2 M(lPPh 2 ) 2 M 0 (NCCH 3 ) 2 ] (M = Pt, M 0 = Pd 3; M = M 0 = Pt, 4, Pd 5) were prepared as described in the references [3,59].…”

“…Several years ago we reported that the tetranuclear [{(C 6 F 5 ) 2 Pt(l-PPh 2 ) 2 M(l-Cl)} 2 ] 2À (M = Pd, Pt) anionic derivatives could be transformed into the tetranuclear clusters [Pt 2 Pd 2 (l-PPh 2 ) 3 (C 6 F 5 ) 3 (PPh 2 C 6 F 5 )] (1) and [Pt 4 (lPPh 2 ) 4 (C 6 F 5 ) 4 ] (2) when the bridging halide ligands were eliminated as silver chloride [1,2]. The structure of the homonuclear Pt complex 2 was established by X-ray diffraction and it resulted to be a tetranuclear cluster with three metal-metal bonds and one phosphido ligand bridging the three metal centres through at least two M-P bonds and a g 2 -phenyl-Pt interaction (see structure in Scheme 1) [2].…”

Reactivity of dimeric cyclopalladated complexes with an (sp)C–Pd bond toward KPPh2

“…Unfortunately, only the X-ray crystallographic data for this compound are available. The 31 P{ 1 H} NMR spectra of known di-m-PPh 2 Pd(II) complexes usually have the signals of the bridging PPh 2 group between À100 and À140 ppm [19,20,34,35,37]. We were able to isolate two complexes, 4a,c, which presumably have dimeric cyclopalladated structure with two bridging PPh 2 ligands.…”