COORDINATION-COMPOUNDS OF THE CHELATING TRIDENTATE PYRAZOLE-CONTAINING LIGAND BIS[2-(3,5-DIMETHYL-1-PYRAZOLYL)ETHYL]AMINE (DDAH) - CRYSTAL AND MOLECULAR-STRUCTURES OF [CU(DDAH)CL](2)(CUCL4), [CO(DDAH)CL](2)(COCL4), [CU(DDAH)CL](BF4), AND [CO(DDAH)CL](BF4)
Pm. Vanberkel et al., COORDINATION-COMPOUNDS OF THE CHELATING TRIDENTATE PYRAZOLE-CONTAINING LIGAND BIS[2-(3,5-DIMETHYL-1-PYRAZOLYL)ETHYL]AMINE (DDAH) - CRYSTAL AND MOLECULAR-STRUCTURES OF [CU(DDAH)CL](2)(CUCL4), [CO(DDAH)CL](2)(COCL4), [CU(DDAH)CL](BF4), AND [CO(DDAH)CL](BF4), Inorganic chemistry, 33(25), 1994, pp. 5920-5926
The synthesis, spectroscopy, and structure of transition-metal coordin
ation compounds of the ligand bis[2-(3,5-dimethyl-1-pyrazolyl)ethyl]am
ine (abbreviated ddaH) are described. The ligand acts as a tridentate
Ns-donor Ligand in the compounds [M(ddaH)Cl](2)(MCl(4)) with M = CU2+,
Co2+, and Zn2+, and in the compounds [M(ddaH)-Cl](BF4) with M = CU2and Co2+ as shown spectroscopically and - in a selected number of case
s - proven by X-ray diffraction. The compound [Cu(ddaH)Cl](2)(CuCl4) c
rystallizes in the monoclinic space group C2/c (Z = 4). The cell dimen
sions are a = 23.207(9) Angstrom, b = 11.614(5) Angstrom, c = 14.408(4
) Angstrom, beta = 90.26(4)degrees, V = 3883(2) Angstrom(3), D-x = 1.5
84 g/cm(3), and R = 0.056 (R(W) = 0.058) for 1765 significant reflecti
ons. The copper(II) ion in the cationic part is surrounded by two pyra
zole nitrogens (Cu-N distances are 1.999(8) and 1.980(7) Angstrom) and
an amine nitrogen (Cu-N distance is 2.022(7) Angstrom) from the ligan
d and by one chloride anion (Cu-Cl distance is 2.232(3) Angstrom) in a
distorted tetrahedral coordination geometry. The compound [Co(ddaH)Cl
](2)(CoCl4) crystallizes in the monoclinic space group C2/c (Z = 4). T
he cell dimensions are a = 20.810(7) Angstrom, b = 13.429(3) Angstrom,
c = 14.284(2) Angstrom, beta = 92.53(2)degrees, V = 3988(2) Angstrom(
3), D-x = 1.519 g/cm(3), and R = 0.040 (R(W) = 0.052) for 2825 signifi
cant reflections. The cobalt(II) ton in the cationic part is surrounde
d by two pyrazole nitrogens (Co-N distances are 2.004(3) Angstrom and
1.982(3) Angstrom) and an amine nitrogen (Co-N distance is 2.068(3) An
gstrom) from the ligand and by one chloride anion (Co-Cl distance is 2
.216(1) Angstrom) in a distorted tetrahedral coordination geometry. Th
e anionic part of both compounds consists of a distorted tetrahedral t
etrachlorometalate(II) with a Cu-Cl distance of 2.215-2.282 Angstrom,
a Co-Cl distance of 2.255-2.289 Angstrom, a Cl-Cu-Cl bond angle of 100
.8-137.0 degrees, and a Cl-Co-Cl bond angle of 104.1-116.4 degrees. Th
ere is a moderately strong hydrogen bridge between the (MCl(4))(2-) an
ion and the amine nitrogen of the ligand ddaH. The shortest distances
from the (MCl(4))(2-) anion to the M(2+) in the cation are 4.26 Angstr
om and 3.673 Angstrom for respectively Co2+ and Cu2+. The compound [Cu
(ddaH)Cl](BF4) crystallizes in the orthorombic space group Pbca (Z = 8
). The cell dimensions are a 10.163(2) Angstrom, b = 19.542(3) Angstro
m, c = 19.647(3) Angstrom, V = 3898(2) Angstrom(3), D-X = 1.524 g/cm(3
), and R = 0.056 (R(W) = 0.032) for 1134 significant reflections. The
Cu2+ ion in [Cu(ddaH)Cl](+) is surrounded by two pyrazole nitrogens (C
u-N distances are 1.977(8) and 1.962(9) Angstrom) and an amine nitroge
n (Cu-N distance is 2.038(9) Angstrom) from the ligand and by one chlo
ride anion (Cu-Cl distance is 2.247(3) Angstrom) in a distorted tetrah
edral coordination geometry. The compound [Co(ddaH)Cl](BF4) crystalliz
es in the monoclinic space group P2(1)/c (Z = 4). The cell dimensions
are a = 12.372(1) Angstrom, b = 14.297(1) Angstrom, c = 12.753(1), bet
a = 117.55(1)degrees, V = 2000(1) Angstrom(3), D-x 1.470 g/cm(3), and
R = 0.046 (R(W) = 0.035) for 2198 significant reflections. The Co2+ io
n in [Co(ddaH)Cl](+) is surrounded by two pyrazole nitrogens (Co-N dis
tances are 1.977(3) and 1. 985(5) Angstrom) and an amine nitrogen (Co-
N distance is 2.057(5) Angstrom) from the ligand and by one chloride a
nion (Cu-Cl distance is 2.207(2) Angstrom) in a distorted tetrahedral
coordination geometry. In all compounds, the tetrafluoroborate anions
are weakly hydrogen bridged to the amine nitrogen of the ligand. The c
ompound [Zn(ddaH)Cl](2)(ZnCl4) is IR isomorphous with the correspondin
g copper(II) and cobalt(II) compounds.