SYNTHESIS AND CHARACTERIZATION OF A NEW NI(II) PYRIMIDINE COMPLEX - CRYSTAL AND MOLECULAR-STRUCTURE OF TRANS-BIS(ISOCYTOSINE-O-4) BIS(ETHYLENEDIAMINE) NI(II) BIS(TETRAPHENYLBORATE)

The lilac complex [Ni(en)(2)(isocyt)(2)] [B(C6H5)(4)](2) (en=ethylened iamine; isocyt=isocytosine) has been prepared by reaction of [Ni(en)(2 )Cl](2)Cl-2 and the pyrimidine base in ethanol-water medium. The compl ex crystallizes in the triclinic space group P-1 with a = 9.488(6), b = 11.020(5), c = 13.986(6) Angstrom, alpha = 84.09(4), beta = 85.33(5) , gamma = 69.04(6)degrees, V= 1356.8(12) Angstrom(3) and Z=1. As obser ved in the cytosine analog, both unsubstituted isocytosine bases are b ound in trans position exclusively via O(4) to the nickel atom. The oc tahedral coordination of Ni(II) is completed by four nitrogen atoms of two ethylenediamine molecules. IR, electronic spectra and magnetic pr operties of the former compound are discussed.