Dimeric, Two‐Dimensional and Metal‐Centered Rectangular Heterometallic Cu^II–Ag^I/Cd^II/Ba^II Systems Derived from a Single Compartmental Ligand

Abstract

The present study deals with one dimer‐of‐dinuclear type compound, [{CuIILAgI(NO3)}2] (1), one pentametallic and metal‐centered rectangle type compound, [BaII(CuIIL)4](ClO4)2 (2), and one dinuclear based two‐dimensional coordination polymer, [CuIILCdII(μ1,5‐dicyanamide)2]n (3), where H2L=N,N′‐bis(salicylidene)‐1,4‐butanediamine. The syntheses and crystal structures of 1–3, electrospray ionization mass spectra in positive mode of 1 and 2 and variable‐temperature magnetic properties of 2, are described. Two symmetry related diphenoxo‐bridged dinuclear CuIIAgI moieties are interlinked in 1 by Ag–π (η2‐) bonds to form dimer‐of‐dinuclear type structure. One diphenoxo‐bridged dinuclear CuIICdII moiety is interlinked with four symmetry related dinuclear moieties by four μ1,5‐dicyanamide ligands, which link CdII centers, to generate two‐dimensional polymeric structure in 3. In the [BaII(CuIIL)4]2+ cation in 2, the BaII ion is coordinated to two μ‐phenoxo oxygen atoms of each of the four [CuIIL] fragments; the four copper(II) ions are positioned to form an approximate rectangle, i. e., the pentametallic [BaII(CuIIL)4]2+ cation in 2 is a metal‐centered rectangle. ESI‐MS positive of 1 and 2 have been recorded and the ions in the spectra have been reasonably assigned. Variable‐temperature magnetic studies of 2 reveal very weak antiferromagnetic interaction (J=–0.14 cm–1) between the copper(II) ions. The structure of 2 represents a new type among compounds from related ligands.