Cyclometalated organoplatinum(ii) complexes: first example of a monodentate benzo[h]quinolyl ligand and a complex with bridging bis(diphenylphosphino)ethane

Abstract

The cyclometalated complexes [Pt(ppy)R(SMe(2))] or [Pt(bhq)R(SMe(2))], where ppyH = 2-phenylpyridine, bhqH = benzo[h]quinoline and R = methyl or p-tolyl, react with bis(diphenylphosphino)ethane, dppe, in a 1:1 ratio to give the corresponding complexes [Pt(κ(1)-C-ppy)R(dppe)] or [Pt(κ(1)-C-bhq)R(dppe)], in which the ppy or bhq ligands are monodentate and dppe is chelating. The similar reaction in a 2:1 ratio gives the binuclear complexes [{Pt(ppy)R}(2)(μ-dppe)] or [{Pt(bhq)R}(2)(μ-dppe)], in which the dppe ligands are in the unusual bridging bidentate bonding mode.

Kinetics and mechanism of oxidative addition of MeI to binuclear cycloplatinated complexes containing biphosphine bridges: Effects of ligands

“…Consistently, attempts to prepare the complex [PtMe(dppf)(bhq-k 1 C)] with the reaction of [PtMe(bhq)(SMe 2 )] with 1 equiv of dppf was unsuccessful. These observations indicate that the rigid ligand bhq, as compared to the more flexible ppy ligand, is less prone to bind as the k 1 form [34].…”

“…Benzo{h}quinoline and 1,1 0 -bis(diphenylphosphino)ferrocene were purchased from commercial sources. [PtMe(bhq)(SMe 2 )] [34] and [Pt 2 Me 2 (bhq) 2 (m-dppm)] [36] were prepared as reported. …”

Oxidative addition of MeI to some cyclometalated organoplatinum(II) complexes: Kinetics and mechanism

“…The starting complexes [PtMe(C^N)(SMe 2 )], A or B, in which C^N ¼ deprotonated 2-phenylpyridine, ppy, or deprotonated benzo [h]quinoline, bhq, respectively, were prepared as reported previously [52]. The analogous complex [PtMe(tpy)(SMe 2 )], C, where tpy ¼ deprotonated 2-(p-tolyl)pyridine, was synthesized similarly by the reaction of [PtMe 2 (m-SMe 2 )] 2 with 2 equiv of 2-(p-tolyl) pyridine.…”

“…The complexes [PtMe 2 (m-SMe 2 )] 2 ,[59] [PtMe(ppy)(SMe 2 )], A, or [PtMe(bhq)(SMe 2 )], B,[52] and [PtMe(ppy)(PPh 3 )], 1a, or [PtMe 2 I(ppy)(PPh 3 )], 2a,[49] were prepared as described previously.4.1.1. [PtMe(tpy)(SMe 2 )], C Pure 2-(p-tolyl)pyridine (120 mL, 0.7 mmol) was added dropwise via syringe to a solution of [PtMe 2 (m-SMe 2 )] 2 (200 mg, 0.35 mmol) in acetone (20 mL) at room temperature.…”

Mono- and binuclear orthopalladated complexes of phosphorus ylides containing nitrogen, phosphorus or bridging diphosphine ligands: Self-assembly, theoretical calculations and comparative catalytic activity

“…The reaction of the precursor complex with diphosphine ligands in a 1:2 molar ratio (Scheme 1) gives the mononuclear bischelate cyclopalladated complex, structurally determined in our previous studies [24,25] while the reaction in a 1:1 molar ratio gives the diphosphino-bridged binuclear complexes (Scheme 1). It is noteworthy that dppe and dppp are very strong chelating ligands in square planar complexes and there are few examples of d 8 metal complexes with bridging dppe and dppp due to their appropriate bite angles [26].…”