Homopiperazine platinum(II) complexes containing substituted disulfide groups:: crystal structure of [PtII(homopiperazine)(diphenylsulfide)Cl]NO3

A series of new cationic platinum(II) complexes of the type [Pt(L)(R'R"S)Cl]NO3 (where L = homopiperazine or 1-methylhomopiperazine and R'R"S = dimethylsulfide, diethylsulfide, dipropylsulfide. diisopropylsulfide, dibutylsulfide, diphenylsulfide, dibenzylsulfide, methylphenylsulfide, or methyl p-tolylsulfide) were synthesized and characterized by elemental analysis and infrared, H-1 and Pt-195 nuclear magnetic resonance spectroscopy. Among the complexes synthesized, [Pt-11(homopiperazine)(diphenylsulfide)Cl]NO3 was examined by single--crystal X-ray diffraction. The slightly distorted square plane or the platinum complex included the amino groups of the homopiperazine molecule in a cis orientation, the sulfur atom of diphenyl sulfide, and a chloride ion. The homopiperazine molecule adopts a boat conformation and forms five- and six-membered chelating rings with platinum. Hydrogen bonding plays an important part in holding the crystal together. (C) 2002 Elsevier Science Ltd. All rights reserved.