SYNTHESIS AND MOLECULAR-STRUCTURE OF N-METHYLPIPERAZINIUM(-DIMETHYLPIPERAZINIUM(+2) PLATINUM(II) AND PLATINUM(IV) COMPLEXES - PART II(1) AND N,N')

Square-planar Pt(II) and octahedral Pt(IV) ionic complexes [H(2)Me(2)p pz](2+) [PtCl4](2-)(1), PtCl3(H(2)Meppz)](2)[H(2)Me(2)ppz](2+)[PtCl4]( 2-). 2H(2)O (2) and [H(2)Me(2)ppz](2+) [PtCl6](2-) (3) have been synth esized and their molecular structure and geometry investigated through X-ray diffraction. The N-methylpiperazinium(+ 1) Ligand bound to Pt(I I) in complex 2 and the dipositive N,N'-dimethylpiperazinium(+2) catio n in complexes 1, 2 and 3 are always present in the energetically favo ured chair conformation. Moreover the crystals of complex 2 show an un usual situation containing at the same time [PtCl3(H(2)Meppz)](2) amph iionic molecules and [H(2)Me(2)ppz](2+) [PtCl4](2-) ions. (C) 1998 Els evier Science S.A. All rights reserved.