Mr. Sundberg et al., EFFECT OF HYDROGEN-BONDING ON COORDINATION IN NOBENZOATO-O)DI(1,3-DIAMINOPROPANE-N,N')COPPER(II) (Z = 2, 3 OR 4) COMPLEX UNITS, Inorganica Chimica Acta, 268(1), 1998, pp. 21-30
The crystal structures of the series of compounds containing the di (Z
-aminobenzoato-O) di(1,3-diaminopropane-N,N')copper(II) (Z = 2, 3 or 4
) coordination units were determined by single-crystal X-ray methods.
In the ortho-and meta-aminobenzoate analogues the structures are compo
sed of monomeric complex units, where a copper(II) cation is located a
t a centre of symmetry and the chelate rings display a chair conformat
ion. The benzoate anions in the axial positions are coordinated via on
e oxygen only. In the para-aminobenzoate analogue the complex units ar
e similar, but there are two additional crystal water molecules in the
asymmetric unit. The main differences between the three coordination
units are seen in the bite angle of a chelate ring and the declination
value of a benzoate anion. The differences are likely due to variatio
n in the participation of an amine group of a chelate ring and a carbo
xylate group of a benzoate anion to form a hydrogen bonding network. I
ntramolecular hydrogen bonding seems to be correlated with inclination
of a benzoate anion. Small inclination and absolute declination value
s for a benzoate anion seem to be related with bifurcated intramolecul
ar hydrogen bonding and narrowing of a bite angle N-Cu-N. The hydrogen
bonding to the coordinated oxygen atom changes its hybridisation from
approximate sp(2) towards sp(3). The existence of hydrogen bonding is
supported by IR spectra. The crystallographic data are as follows (tn
: 1,3-diaminopropane; bzO: a benzoate anion): [Cutn(2)(2NH(2)bzO)(2)],
C20H32CuN6O4, monoclinic, space group P2(1)/a No. 14, a=10.513(2), b=
9.1789(12), c=12.126(2) Angstrom, beta=99.82(2)degrees, V=1153.0(4) An
gstrom(3); [Cutn(2)(3NH(2)bzO)(2)], C20H32CuN6O4, monoclinic, space gr
oup P2(1)/n No.14, a=6.7128(12), b=16.503(4), c=10.268(2) Angstrom, be
ta=92.022(15)degrees, V=1136.8(4) Angstrom(3); [Cutn(2)(4NH(2)bzO)(2)]
. 2H(2)O, C20H36CuN6O6, monoclinic, space group P2(1)/n No.14, a=9.484
(2), b=8.938(2), c=16.301(3) Angstrom, beta=103.910(14)degrees, V=1334
.6(5) Angstrom(3). (C) 1998 Elsevier Science S.A.