Reaction of anionic oxygen donors with the antitumour copper(II)–pyridine-2-carbaldehyde thiosemicarbazone (HL) system and the crystal structure of [{Cu(HL)(H2PO4)}2][H2 PO4]2·2H3PO4 ·2H2O
Abstract
The complexes
[(CuL)
2
(XO
4
)]·nH
2
O
(HL = pyridine-2-carbaldehyde thiosemicarbazone,
X = HP, n = 6;
X = Mo, n = 1),
[{CuL(ptp)}
2
]·4H
2
O
(Hptp = p-tritylphenol) and
[{CuL(tip)}
2
]
(Htip = 2,4,6-triiodophenol) have been prepared from the
reaction of aqueous solutions of
[{CuL(CH
3
CO
2
)}
2
] with salts
of the appropriate oxygen donor. Also prepared were
[{Cu(HL)(H
2
PO
4
)}
2
][H
2
PO
4
]
2
·xH
3
PO
4
·nH
2
O (x = 0,
n = 3; x = 2,
n = 2) from the reaction of
[{CuL(CH
3
CO
2
)}
2
] with 2 mol
dm
-3
H
3
PO
4
and phosphate species
(arising from the hydrolysis of 2 mol dm
-3
HPF
6
) respectively. The complexes have been characterized by
a range of physicochemical techniques and the crystal and molecular
structure of
[{Cu(HL)(H
2
PO
4
)}
2
][H
2
PO
4
]
2
·2H
3
PO
4
·2H
2
O determined by single-crystal X-ray diffraction.
The complex cation is a centrosymmetric dimer, the monomeric units
having one-atom bridges from two
H
2
PO
4
-
anions. The copper atom
has a distorted square-pyramidal geometry with three donor atoms (NNS)
from the neutral, tridentate HL ligand and the fourth in-plane donor (an
oxygen) from the bridging anion. The fifth position is occupied by a
less strongly bound oxygen from the second bridging anion. An extensive
hydrogen-bonding scheme involving the bridging
H
2
PO
4
-
anions, non-co-ordinated
H
2
PO
4
-
anions,
H
3
PO
4
moieties, water molecules and ligand exists
with one very strong contact of 2.436 Å. These complexes
may serve as simple models for the interaction of this antitumour system
with oxygen donors.
Please wait while we load your content...
