A. Garciaraso et al., SYNTHESIS AND STRUCTURE OF ISOCYTOSINE TERNARY COPPER(II) COMPLEXES, Journal of the Chemical Society. Dalton transactions, (6), 1998, pp. 1031-1036
The ternary complexes (glycylglycinato)(isocytosine)copper(II) dihydra
te 1 and (glycylglycinato)(6-methyl-isocytosine)copper(II) monohydrate
2 have been prepared and characterised by X-ray diffraction, electroc
hemistry and optical, ESR and IR spectroscopy. The two compounds are s
lightly distorted square planar, with the four co-ordination sites occ
upied by the tridentate glycylglycine dianion [O(7), N(13) and N(10)]
and N(3) of the pyrimidine base. An additional weak axial interaction
exists between an oxygen of a water molecule O(W1) and the copper atom
[Cu ... O(W1) distances 2.74 and 2.70 Angstrom respectively]. Spectro
scopic and electrochemical data are in accord with the crystal structu
res. Although both compounds exhibit irreversible oxidation processes,
the oxidation of Cu-II to Cu-III is best performed with the isocytosi
ne complex.