188829-89-2Relevant academic research and scientific papers
Preparation, via double oxidative addition, and characterization of bimetallic platinum and palladium complexes: Unique building blocks for supramolecular macrocycles. 13C NMR analysis of the nature of the palladium-carbon bond
Manna, Joseph,Kuehl, Christopher J.,Whiteford, Jeffery A.,Stang, Peter J.
, p. 1897 - 1905 (1997)
The high-yield preparation, by double oxidative addition, of nine novel platinum and palladium bis(trans-M(PR3)2X)aryl (M = Pt or Pd; R = PPh3 or PEt3; X = Br or I; aryl = 1,4-benzene, 4,4′-biphenyl, 4,4″-ter-p-phenyl, 4,4′-tolane, or 4,4′-benzophenone) complexes from the reaction of Pt(PPh3)4, Pt(PEt3)4, or Pd(PPh3)4 with the respective dihalo aromatic in toluene is described. These complexes were fully characterized by elemental analysis, mass spectrometry, and NMR (1H, 13C{1H}, and 31P{1H}) and vibrational (IR or Raman) spectroscopies. The single-crystal molecular structure of 4,4′-bis(trans-Pt(PEt3)2I)biphenyl (2a) was determined by X-ray crystallography. The key structural feature of this complex is the dihedral angle of 18.9° between the two planes defined by the phenyl groups of the biphenyl linkage. The nature of the palladium-carbon bond is investigated by 13C{1H} NMR spectroscopy; Taft's σR parameter is found to correlate in a linear fashion with [δ(Cipso) - δ(Co)] for these palladium complexes. These data indicate the 13C chemical shift of Cipso is linearly related to the amount of π-electron density of the carbon bound to the palladium center. The potential utility of these bimetallic platinum and palladium complexes as subunits in the generation of organometallic macrocycles is described.
Preparation, structural studies, and magnetic properties of coordination complexes of bimetallic arylplatinum compounds and pyridyl nitronyl nitroxide radicals
Gardinier, James R.,Clerac, Rodolphe,Gabbai, Francois P.
, p. 3453 - 3458 (2007/10/03)
Treatment of 1,3-C6H4I2 with Pt(PEt3)4 in toluene leads to the isolation of [1,3-(Pt(PEt3)2I)2 C6H4] (2). This complex has been characterized by 1H, 13C and 31P NMR and elemental analysis. The structure of 2 as well as that of [1,4-(Pt(PEt3)2I)2C6H4] (1) have been determined by single crystal X-ray analysis. As expected, the platinum centers of these derivatives adopt a square planar coordination geometry with the phosphine ligands in a trans arrangement. Treatment of compounds 1 and 2 with AgPF6 and subsequent addition of two equivalents of NITpPy (NITpPy = [2-(4-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide]) results in the formation of [1,4-(Pt(PEt3)2(NITpPY))2C6H4 ]2+[PF6]-2 (3) and [1,3-(Pt(PEt3)2(NITpPy))2C6H4 ]2+[PF6]-2 (4), respectively. Compounds 3 and 4 have been characterized by +ESI/TOF, IR, UV and elemental analysis. Their structures have been determined by X-ray crystallography which confirmed the coordination of a NITpPy ligand at each platinum center. As in 1 and 2, the platinum centers adopt a square planar coordination geometry with the phosphine ligands in a trans arrangement. As shown by EPR spectroscopy and SQUID magnetometry, intramolecular magnetic coupling of the coordinated NITpPy moieties does not occur.
