CRYSTAL STRUCTURES OF
[Cu(L)2(dca)]PF6 COMPLEXES, WHERE L =
1,10-PHENANTHROLINE OR 2,2’-BIPYRIDINE, AND dca = DICYANAMIDE ANION, N(CN)
.
Milan Burčák and Ivan Potočňák
Department
of Inorganic Chemistry, Faculty of Science, P. J. Šafárik University, Moyzesova 11, SK-041 54 Košice, Slovakia
With the aim of finding
out possible reasons for different shapes of coordination polyhedra (SCP) in
related compounds, we have previously studied the structures of
five-coordinated copper(II) complexes of the general formula [Cu(L)2(dca)]X, where dca = N(CN)
, L = phen and X = C(CN)
, CF3SO3 (phen = 1,10-phenanthroline),
or L = bpy and X = BF
, ClO
, C(CN)
, CF3SO3 (bpy =
2,2´-bipyridine) [1, 2]. The SCP in these compounds is more or less distorted
trigonal-bipyramidal. Now, we widen the series by X = PF
, and here we present the structures of [Cu(phen)2dca]PF6
(1) and [Cu(bpy)2dca][Cu(bpy)2(H2O)](PF6)3
(2). The copper atom in 1 is coordinated by two phen molecules
and one dca. On the other hand, there are two different copper atoms in 2,
which are coordinated by two bpy molecules, while the fifth coordination places
are occupied by one dca or water molecule, respectively. Nevertheless,
according to [3], all copper atoms in 1 and 2 are coordinated in
the form of a distorted trigonal bipyramid. The charges of the complex
cations in 1 and 2 are neutralized by uncoordinated PF
anions. In addition to ionic forces, the structures are
stabilized by weak hydrogen bonds and possible p-p interactions. The problems that occurred
during the solving of the structures will be discussed.
This work was supported by the VEGA no. 1/0447/03
and APVT-20-009902 grants.
REFERENCES
1.
I. Potočňák, M
Burčák, C. Wagner & L. Jäger, Acta Cryst. -
accepted.
2.
M. Burčák &
I. Potočňák, submitted to 55th Congress of chemical societies, Košice,
Slovakia, 2003.
3. R.R.Holmes & J.A. Deiters, J. Am. Chem. Soc., (1977) 3318-3326.