Crystal and molecular structure of trichloro(π-trans-but-2-en-1,4-diammonium)platinum(II) chloride

The structure of the olefin complex, [PtCl3(C4H12N2)]+, of platinum(II) with the trans-but-2-en-1,4-diammonium cationic ligand, has been determined as its hemihydrate chloride salt, by single-crystal X-ray methods. The compound [PtCl3(C4H12N2)]Cl,½H2O forms yellow monoclinic crystals, a= 23·911, b= 6·942, c= 13·586 A, β= 102·07°, space group C2/c with Z= 8. The structure, solved by standard methods, has been refined anisotropically by full-matrix least-squares methods to R 0·037, by use of 2447 independent reflections collected by counter methods.The structure contains discrete ions linked into infinite two-dimensional layers by chains of O–H ⋯ Cl, N–H ⋯ O, N–H ⋯ Cl hydrogen bonds. In the cation, platinum is four-co-ordinate with the three chlorine atoms and the double bond of the unsaturated diammonium cationic ligand. The structure of the complex is discussed together with the changes in the olefin caused by co-ordination. Comparison with similar platinum(II)–olefin complexes is made.