Binuclear and polynuclear transition metal complexes with macrocyclic ligands 1. Synthesis and the structure of an antiferromagnetic binuclear nickel complex prepared by the reaction of o-phenylenediamine with pyrrole-2,5-dicarbaldehyde and nickel pivalate.
The reaction of pyrrole-2,5-dicarbaldehyde (1) with o-phenylenediamine (2) in anhyd. EtOH afforded a [1+1]-condensation product, viz., Schiff's base. The structure of the latter was established by NMR spectroscopy and x-ray diffraction anal. The reaction of this product or a mixt. of 1 and 2 with Ni9(mn-OOCBut)12(HOOCBut)4(m4-OH)3(m3-OH)3 in MeCN in the presence of AcOH gave rise to an antiferromagnetic binuclear complex. According to the x-ray diffraction data, the macrocycle in the latter complex is a [2+2]-condensation product of compds. 1 and 2, meff ranging from 0.569 to 2.614 mB (2-301 K), -2J = 360 cm-1. The Ni2(OAc)2 fragment is located in the central cavity of the macrocycle. The structures of the condensation products are discussed based on the results of DFT quantum-chem. calcns.
Record created on 2006-10-11, modified on 2016-08-08