Expanding the allyl analogy: accessing η3-P,B,P diphosphinoborane complexes of group 10

A neutral, acyclic, borataalkene-like ligand for group 11 metals: L- and Z-type ligands side by side

The overall neutral α-borylated phosphorus ylide Ph₃PC(Me)BEt₂ behaves like a polar borataalkene and can act as acyclic, ambiphilic π-type ligand with L- and Z-type functionalities side by side. In the complexes [MX{η²-Ph₃PC(Me)BEt₂}] (M = Cu, (Ag), Au; X = Cl, NTf₂), the bonding is dominated by the highly nucleophilic ylidic carbon atom (L-type ligand). The Lewis acidic boron atom furnishes nonetheless a small but significant bonding contribution (Z-type ligand).

Dynamics of the efficient cyclometalation of the undercoordinated organoplatinum complex [Pt(COD)(neoPh)]+ (neoPh = 2-methyl-2-phenylpropyl)

The cyclometalation reaction of [Pt(COD)(κ¹-neoPh)]⁺ (neoPh = 2-methyl-2-phenylpropyl) to [Pt(COD)(κ²-neoPh)] was studied experimentally and mechanistically using DFT and MD simulations.

Platinum complexes of a boron-rich diphosphine ligand

Herein, we describe the preparation, characterization, and reactivity of two Pt^II bis-hydrocarbyl complexes containing the 1,2-bis(di(3-dicyclohexylboraneyl)propylphosphino)ethane (P₂B^Cy₄) ligand.

Structural and spectroscopic analysis of a new family of monomeric diphosphinoboranes

We present a series of amino- and aryl(diphosphino)boranes R₂PB(R'')PR'₂, where R₂P, R'₂P = tBu₂P, tBuPhP, Ph₂P, Cy₂P, and R'' = iPr₂N, Ph, which were obtained via the metathesis reaction of iPr₂NBBr₂ or PhBBr₂ with selected lithium phosphides. The structures of isolated diphosphinoboranes were characterized in the solid state and in solution by means of X-ray diffraction and NMR spectroscopy, respectively. The utility of these P-B-P species as ligands for transition metal complexes was tested in the reaction with [(COD)PtMe₂]. Moreover, we carried out DFT calculations to elucidate bonding interactions and philicity of the reactive centers as well as to analyze conformations of the studied species. Electronic and steric properties of substituents on P and B atoms were found to have a strong influence on the structures of the obtained compounds. Three main types of diphosphinoboranes were distinguished, based on the strength of P-B π-interaction within the molecule: (i) application of strong electron-donating substituents on P-atoms and electron-accepting phenyl groups on B atoms led to the structure with one double P[double bond, length as m-dash]B and one single P-B bond and diverse planar and pyramidal geometry of phosphanyl groups; (ii) reduction of the donor ability of phosphanyl groups gave diphosphanylboranes with delocalized P-B-P π-interactions; (iii) introduction of amino groups with strong donor abilities on B atoms canceled P-B π-interactions and allowed compounds with two very long P-B bonds and two pyramidal phosphanyl groups to be obtained.

Reactions of the organoplatinum complex [Pt(cod) (neoSi)Cl] (neoSi = trimethylsilylmethyl) with the non-coordinating anions SbF6– and BPh4–

Reactions of the organoplatinum complex [Pt(cod)(neoSi)Cl] (neoSi = (trimethylsilylmethyl) with the Ag(I) salts of oxo or fluoride containing anions A– = NO3–, ClO4–, OTf – (trifluoromethanesulfonate) and SbF6– lead to the desired abstraction of the chlorido ligand and precipitation of AgCl. However, further reaction of the resulting Pt complexes [Pt(cod)(neoSi) (solvent)]+ with diverse N-heterocyclic ligands L such as pyridines, caffeine, and guanine did not yield the targeted complexes [Pt(cod)(neoSi)(L)](A) in most of the cases, but to extensive decomposition yielding [Pt(cod)(Me) (solvent)]+, thus transforming the neoSi into a methyl ligand. A detailed study on the reaction with SbF6– combining DFT calculations with NMR and MS revealed that Pt catalysed decomposition of SbF6‒ and fluorination of the neoSi silicon atom leading to FSiMe3. When reacting the parent complex with Ag(BPh4), the arylated derivative [Pt(cod)(neoSi)(Ph)] was obtained and characterised by multinuclear NMR, MS and single crystal XRD.