Self-assembly of the unique heterotrimetallic Cu/Co/M complexes possessing triangular antiferromagnetic {Cu2CoPb}2 and linear ferromagnetic {Cu2CoCd2} cores

Two novel heterotrimetallic octa-[Cu2CoPbCl4(L)4]2 (1) and pentanuclear [Cu2CoCd2Cl6(L)4(HOMe)2] (2) complexes have been prepared in one-pot reactions of zerovalent copper with metal chlorides in a methanol (for 1) or acetonitrile (for 2) solution of 2-(dimethylamino)ethanol (HL) in open air. The crystal structures of both compounds consist of discrete centrosymmetric heterotrimetallic molecules revealing triangular (1) and unique consecutive (2) arrangements of magnetic CuII2CoII cores. The complex 1 can be viewed as a dimer made up of tetranuclear Cu2CoPbCl4(L)4 units linked through the two µ2-Cl atoms. The molecular structure of 2 is a pentanuclear assembly containing the previously unknown Cu(µ-O)2Co(µ-O)2Cu core. The magnetic studies of 1 revealed an antiferromagnetic coupling (JCoCu = 37 cm−1 and JCuCu = 87 cm−1) while 2 exhibits a weak ferromagnetic behavior (JCoCu = −3.2 cm−1 and JCuCu = −14.2 cm−1). The correlations between magnetic behaviour and structures as well as synthetic features are also discussed.