Stereoselective C-X and regioselective C-H activation to, and selective C(sp)-C(sp) reductive elimination from, platinum compounds with thiophene-derived ligands

Ligand-Mediated C–Br Oxidative Addition to Cycloplatinated(II) Complexes and Benzyl-Me C–C Bond Reductive Elimination from a Cycloplatinated(IV) Complex

“…C–C bond-forming reductive elimination is well recognized as the last step in many catalytic cycles used in organic synthesis. − Such processes have been studied extensively including Pt­(IV) complexes. − Although there are some reports on C–C bond formation from the organoplatinum (IV) complex involving Me–Me or acyl-Me, ,,− a limited number of studies on the intramolecular C–C reductive elimination from Pt­(IV) complexes, especially C–C benzyl-methyl reductive elimination, are reported . Goldberg and Crumpton reported C–C reductive elimination reactions from Pt­(IV) complexes .…”

Synthesis, Structure, and Photophysical Properties of Platinum Compounds with Thiophene-Derived Cyclohexyl Diimine Ligands

“…26,30 Among aromatic rings, thiophenes have been reported to be reactive toward C−H activation and are excellent candidates for preparing cyclometated complexes through C−H activation reactions. 14,31 Using this diimine C^N^N ligand framework, we report the synthesis, structural characterization, and photophysical properties of new Pt(II)/ Pt(IV) complexes and have compared their properties with the structurally related benzene-derived complexes reported earlier by Puddephatt. 19,20 We report their luminescence in both solution and solid media for these four complexes, as a major focus of recent research in luminescent inorganic complexes is the impact of physical state and intermolecular order on photophysical properties.…”

“…Cyclometalated complexes of Pt are most often prepared by the well-known C–H and C–X (X = Cl, Br, I) oxidative addition reactions of appropriately designed ligands. The initial coordination of neutral donor atoms in the ligands such as N, O, and P direct the oxidative addition in heteroatom-assisted C–H/C–X activation, leading to the cyclometalated product. ,− In order to realize high-yielding syntheses of cyclometalated Pt complexes, ligands that react with high regioselectivity and stereoselectivity are essential. In general, this requires careful ligand design, as many possible regiochemical and stereochemical products may result from C–H/C–X reactivity of organic ligands.…”

“…In this work, we explore a new type of cyclohexyl diimine C^N^N ligand featuring a thiophene ring, as is shown in Scheme . Conjugated thiophene polymers and oligomers are attractive organic optoelectronic materials in their own right, − and metal complexes featuring metalated or pendant thiophenes with interesting photophysical properties have been reported. − In particular, metalated thiophenes as compared to phenyl groups in structurally analogous Pt­(II) complexes have been reported to enhance fluorescence over phosphorescence in recent studies. , Among aromatic rings, thiophenes have been reported to be reactive toward C–H activation and are excellent candidates for preparing cyclometated complexes through C–H activation reactions. , Using this diimine C^N^N ligand framework, we report the synthesis, structural characterization, and photophysical properties of new Pt­(II)/Pt­(IV) complexes and have compared their properties with the structurally related benzene-derived complexes reported earlier by Puddephatt. , We report their luminescence in both solution and solid media for these four complexes, as a major focus of recent research in luminescent inorganic complexes is the impact of physical state and intermolecular order on photophysical properties. − …”