Cu(II) complexes with a pendant octaazamacrocycle and μ-bonded aromatic carboxylates

Abstract

Three new cationic mixed-ligand Cu(II) complexes with N,N′,N″,N‴-tetrakis(2-pyridylmethyl)-1,4,8,11- tetraazacyclotetradecane (tpmc) and bridging aromatic mono- or dicarboxylate ligands were prepared. Elemental analysis, conductometric and magnetic measurements, as well as electronic and IR spectroscopy were employed for their characteriization. It is proposed that the complexes [Cu2(C6H5COO)tpmc](CIO4) 3MeOH and [Cu2(Hpht)tpmc](CIO4). 3H2O (H2pht = phthalic acid) are binuclear with μ-coordination of the carboxylate monoanions. The third complex, [Cu4ipht(tpmc)2](CIO4)6NaClO 42MeCN (H2ipht = isophthalic acid) is one of the rare tetranuclear Cu(II)-tpmc complexes with an aromatic dicarboxylate ion bridging two Cu2tpmc units. This was also confirmed by preliminary results of the determination of the crystal structure.