Four trinuclear Cu(II) complexes bridged by N-heterocyclic multicarboxylic acids: [Cu 3(dien) 2(μ 2-Pz 3,5-dc) 2(H 2O) 2]·4H 2O (1), [Cu 3(pmdien) 2(μ 2-Py 2,5-dc) 2(ClO 4) 2(H 2O) 2] (2), [Cu 3(trpn) 2(μ 2-Py 2,5-dc) 2(ClO 4) 2] (3) and [Cu 3(ip 3tren) 2(μ 2-Py 2,4-dc) 2(H 2O)](ClO 4) 2 (4) and the coordination polymer: catena-[Cu 2(bedmpza) 2(μ 2-Py 2,4-dc)](ClO 4) 2·H 2O (5) as well as the monomeric [Cu(bdmpzpy)(Py 2,6-dc)] 2·3H 2O (6), where H 3Pz 3,5-dc = 3,5-pyrazole dicarboxylic acid, H 2Py 2,4-dc = 2,4-pyridine dicarboxylic acid, H 2Py 2,5-dc = 2,5-pyridine dicarboxylic acid, H 2Py 2,6-dc = 2,6-pyridine dicarboxylic, dien = diethylenetriamine, pmedien = N,N,N′,N″,N″-pentamethyldiethylene-triamine, bedmpza = bis(3,5-dimethylpyrazolyl-1H-ethyl)amine, trpn = tris(3-aminopropyl)amine, ip 3tren = tris(2-isopropyl-2-ethyl)amine and bdmpzpy = 2,6-bis[(3,5-dimethyl-1H-pyrazolyl)methyl]pyridine were synthesized. The compounds were structurally characterized by elemental microanalyses, IR and UV–Vis spectra as well as by single crystal X-ray crystallography for 1–3, 5 and 6. In 1–3 and 5, the N-heterocyclic multicarboxylate dianion linkers are simultaneously bound by at least one N,O chelating hetero-aromatic dicarboxylato anions via ring-N atom and one O-atom of the adjacent carboxylato group and an O-atom of the carboxylates located at the other side of the heteroxyclic ring. In complex 6 the adjacent bdmpzpy ligands constitute π-π interactions through the central pyridine rings with separation of the centers of gravities = 3.666(2) Å. The degree of nuclearity in the polynuclear species depends entirely on the skeletal structure of the linker N-heterocyclic multicarboxylic acids and the amine coligands.
ASJC Scopus subject areas
- Anorganische Chemie
- Physikalische und Theoretische Chemie