Organoamidometallics. V. Syntheses of [N,N-diethyl-N'-polyfluorophenyl-ethane-1,2-diaminato(1-)]platinum(II) Complexes by Decarboxylation Reactions, and the X-Ray Crystal Structure of trans-[Pt(NC₆F₅CH₂CH₂Net₂)I(Py)]

Abstract

From reactions between PtX₂( deen ) (X=I, Br or Cl ; deen = N,N-diethylethane-1,2-diamine), thallous pentafluorobenzoate or 2,3,5,6-tetrafluorobenzoate, and the appropriate polyfluorobenzene in pyridine (py) or 4-methylpyridine ( mepy ), the organoamidoplatinum (II) complexes [Pt(NRCH₂CH₂Net₂)X(L)](R = p-HC₆F₄ or C₆F₅, X = 1, Br or Cl , L = py; R = p-HC₆F₄, X = I, L = mepy ; R = p-MeC₆F₄ or p-IC₆F₄, X = I, L = py; R = 2,3,5-F₃C₆H₂, X = Br, L = py) have been prepared. The X-ray crystal structure of [Pt(NC₆F₅CH₂CH₂Net₂)I(py)](triclinic, space group Pī (No. 2), a 9.308(1), b 9.615(2), C 11.143(2)Ǻ, α 88.70(2),β 88.58(1), γ 89.60(2)°, R 0.0518, Rw 0.0704 for 3237 observed reflections) shows the complex to have square planar stereo-chemistry with py trans to NEt₂ and NC₆F₅ trans to iodine. The stereochemistry of the amido nitrogen approaches triangular (sum of angles 353°) and the N-C₆F₅ bond has partial double-bond character. Surprisingly, the ethyl substituents have a configuration in which the methyl groups are orientated back towards platinum. Other [Pt(NRCH₂CH₂Net₂)X(L)] complexes are considered to have similar stereochemistry on the basis of comparison of spectroscopic data, particularly ³J_Pt,H(py) and ³J_Pt,H(CH2) coupling constants.