Transition metal compounds of the tridentate pyrazole substituted amine ligand bis(2-(3,5-dimethyl-1-pyrazolyl)ethyl)ethylamine (ddae). X-ray structures of [Co(ddae)(NO 3) 2], [Cu(ddae)(NO 3)(H 2O)](NO 3) and [Cu(ddae)(Cl) 2]·C 2H 5OH

• Published in: Inorganica Chimica Acta Vol. 216; no. 1; pp. 43 - 49
• Main Authors: Driessen, W.L., de Graaff, R.A.G., Parlevliet, F.J., Reedijk, J., de Vos, R.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1994
• Subjects: Chelate complexes; Copper complexes; Crystal structures; Tridentate ligand complexes; Crystal structures; Chelate complexes; Tridentate ligand complexes; Copper complexes
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/0020-1693(93)03707-H

Six new compounds of the ligand bis(2-(3,5-dimethyl-1-pyrazolyl)ethyl)ethylamine (ddae), viz. [Co(ddae)(NO 3) 2], [Ni(ddae)(NO 3) 2], [Cu(ddae)(Cl) 2]·(C 2H 5OH), [Cu(ddae)(NO 3)(H 2O)](NO 3), [Ni(ddae)(H 2O)(BF 4) 2] and [Cu(ddae)(F)(BF 4)] are described. These transition metal compounds are mononuclear. In all cases ddae acts as a tridentate ligand. The cobalt and nickel nitrates are isomorphous, otherwise these compounds all have different structures. The compound [Cu(ddae)Cl 2]·C 2H 5OH crystallizes in the monoclinic space group P2 1/ c with a=8.327(1), b=14.782(2), c=18.654(3) Å, β=96.53(1)° and Z=4. The structure was solved by heavy-atom methods and refined by least-squares methods to a residual R of 0.048 ( R w=0.081) for 2787 significant reflections. The asymmetric unit comprises the whole formula unit. The surrounding geometry of the Cu(II) ion is distorted square-pyramidal with the two pyrazole nitrogens (CuN distances 1.984(4) and 1.999(4) Å) and the two chloride ions (CuCl distances 2.322(2) and 2.400(2) Å) in a square and the amine nitrogen (CuN distance 2.181(4) Å) at the apex. The ligand is coordinated in a mer geometry. The ethanol molecule is hydrogen bonded to one of the chloride ions with a ClO distance of 3.24(1) Å. The compound [Cu(ddae)(NO 3)(H 2O)](NO 3) crystallizes in the orthorhombic space group Pna2 1 with a=24.984(5), b=10.798(2), c=8.466(3) Å and Z=4. The structure was solved by heavy-atom methods and refined by least-squares methods to a residual R of 0.048 ( R w=0.069) for 960 significant reflections. The asymmetric unit comprises the whole formula unit. The Cu(II) ion is in a distorted square-pyramidal environment of the two pyrazole nitrogens at 2.00(1) and 2.01(1) Å, a water oxygen atom at 1.938(9) Å, and an oxygen atom of one of the nitrate ions at 2.00(1) Å in a square, and the amine nitrogen at 2.34(1) Å at the apex. The ligand is folded and coordinated in a fac geometry. If the nitrate ion was regarded as bidentate-coordinate with the rather too long CuO distance of 2.63(1) Å, then the copper ion would be in a strongly distorted octahedral environment. The water molecule is hydrogen bonded to the non- coordinated nitrate ion in two different, symmetry related, positions, with OO distances of 2.74(1) and 2.81(2) Å, in such a way that the complex cations are linked together in a chain. The compound [Co(ddae)(NO 3) 2] crystallizes in the monoclinic space group P2 1/ c with a=16.351(3), b=15.708(2), c=8.484(1) Å, β=104.78(1)° and Z=4. The structure was solved by heavy-atom methods and refined by least-squares methods to a residual R of 0.077 ( R w=0.065) for 1502 significant reflections. The asymmetric unit comprises the whole formula unit. The surrounding geometry of the Co(II) ion is distorted octahedral, with the ligand folded in a fac geometry with the N(amine) at 2.209(9) Å and the N(pyrazoles) at 2.030(10) and 2.112(9) Å. One of the nitrate ions is monodentate with CoO of 2.060(8), the other nitrate is quite symmetrically bidentate coordinated to the cobalt ion with CoO distances of 2.172(8) and 2.216(8) Å.