Threefold Cross‐Linked Polystyrene–Triphenylphosphane Hybrids: Mono‐P‐Ligating Behavior and Catalytic Applications for Aryl Chloride Cross‐Coupling and C(sp³)H Borylation

Abstract

Covalently bound polystyrene-phosphane hybrids were prepared by a method based on radical emulsion polymerization of styrenes in the presence of a tris(p-vinylphenyl)phosphane cross-linker. These hybrids favor mono-P-ligation to transition-metal complexes and are useful for challenging catalysis, such as Pd-catalyzed CC/CN couplings with unactivated chloroarenes and Ir- or Rh-catalyzed C(sp(3) )H borylations.

Metal‐Phosphide‐Containing Porous Carbons Derived from an Ionic‐Polymer Framework and Applied as Highly Efficient Electrochemical Catalysts for Water Splitting

“…Given that the SS 13 C NMR spectra for HC‐TVP and HT‐I are quite similar, the 31 P NMR spectra (Figure b) were further used to define the structure of the two polymers. For HT‐I, the resonance at 29.5 ppm typically corresponded to the ionic phosphorous atoms, which is completely different from the signal at –5.6 ppm for the neutral phosphorous atoms of HC‐TVP . This result is consistent with the solution 31 P‐NMR chemical shift of the model compound PPh 3 ‐HI (Ph = phenyl; Figure S1 in the Supporting Information, SI), indicating the successful ionization of the phosphorous‐based polymer frameworks after treatment with hydriodic acid.…”

“…The strategy for the synthesis of cationic porous polymers loaded with metal‐containing anions is presented in Scheme . Firstly, tris(4‐vinylphenyl)phosphane (TVP) was utilized as the key monomer for preparing hyper‐cross‐linked tri(4‐vinylphenyl) phosphane (HC‐TVP) through azodiisobutyronitrile (AIBN)‐promoted radical polymerization. Afterwards, the resulting HC‐TVP was converted to the ionic polymer (HT‐I), consisting of a cationic framework and iodide counter‐anions under the treatment of aqueous HI for 24 h. HT‐I can be uniformly dispersed in some common organic solvents, such as dimethylformamide (DMF, 1.0 mg mL −1 ) and dioxane.…”

Tripod Immobilization of Triphenylphosphane on a Silica‐Gel Surface to Enable Selective Mono‐Ligation to Palladium: Application to Suzuki–Miyaura Cross‐Coupling Reactions with Chloroarenes

“…Immobilization on a solid surface, for site isolation, could be an efficient strategy for making Ph 3 P an effective ligand for Pd‐catalyzed cross‐coupling reactions. Linking the Ph 3 P core, which has C 3 v symmetry, to the solid surface in a tripodal manner13–15 by using linkers that possess minimal flexibility is possibly the most effective way to achieve immobilization. If the solid surface is assumed to be virtually flat, the cone‐shaped Ph 3 P core would stand upright on the surface, turning its P‐atom lone pair upwards, resulting in effective site isolation and preventing steric interactions between the solid surface and the catalytic center.…”

Palladium‐Catalyzed O‐Arylation Reaction Using Different Heterogeneous Catalyst Systems: The Role of Support

“…In the last decades, coupling reactions (like O‐arylation) catalyzed by palladium have played an important role in organic transformations and ligands with phosphorus atoms are excellent choice because of their high efficiency and applicability in transition metal‐catalysis . Furthermore, P,N ligands with the π ‐acceptor property of phosphorus can stabilize a palladium centre in a low oxidation state, whereas the σ‐donor character of nitrogen atom makes the palladium metal center more susceptible to oxidative addition reactions .…”