Formation of two stable seven-membered chelate rings bound to one metal center due to addition of bifunctional amine to coordinated nitriles

Reaction of cis- and trans-[PtCl2(PhCN)(2)] with three equivalents of ethyl enediamine in water leads to [Pt(NH=C(Ph)NHCH2CH2NH2)(2)]Cl-2 isolated as h is-hydrate, Metathetical reactions of this complex with NaPF6 or KSbF6 in a queous solution give rise to precipitations of the appropriate [Pt(NH=C(Ph) NHCH2CH2NH2)(2)]X-2 . nH(2)O [X = PF6; n = 3; X = SbF6; n = 2] salts. The b is-hydrate [Pt(NH=C(Ph)NHCH2CH2NH2)(2)]Cl-2. 2H(2)O was also obtained upon treatment of the platinum(IV) complex [PtCl4(PhCN)(2)] with ethylenediamine in the same reaction conditions. The X-ray diffraction analysis performed on a single crystal having formulation [Pt(NH=C(Ph)NHCH2CH2NH2)(2)](sbF(6)) (2) showed that the complex ion contains two unusual seven-membered organic metallacycles bound to the same platinum(II) center. (C) 1999 Elsevier Sci ence S.A. All rights reserved.