Structural Diversity Ranging from Oligonuclear Complexes to 1‐D and 2‐D Coordination Polymers Generated by Tetrasubstituted Adamantane and Spirobifluorene Derivatives

Abstract

Using tetrahedral and tetragonal spacers, seven new complexes have been obtained: [Co(hfac)2(L1)0.5] 1, [Cu2(hfac)4L2] 2, [Co(hfac)2L2] 3, [Co(hfac)2(L2)0.5]·8H2O 4, [AgL2](SbF6)·CH3COOC2H5 5, [Mn(hfac)2(L3)0.5] 6, [Zn(OAc)2(L3)0.5] 7, {L1 = 1,3,5,7‐tetrakis(4‐cyanophenyl)adamantane, L2 = 2,2′,7,7′‐tetracyano‐9,9′‐spirobifluorene and L3 = 2,2′,7,7′‐tetra(4‐pyridyl)‐9,9′‐spirobifluorene, Hhfac = hexafluoroacetylacetone}. Compound 1 exhibits a 2‐D grid‐like structure with the tetradentate spacer acting as a 4‐connecting ligand. The 2,2′,7,7′‐tetrasubstituted‐spirobifluorene derivatives connect the {MII(hfac)2} entities into a binuclear complex (2), a linear chain (3) and diamond chains (4, 6). The cis or trans configuration of the metal nodes influences the overall topology (MII = CuII, CoII, MnII). Similarly, a 1‐D double chain topological motif results by linking zinc ions and L3 in compound 7. Compound 5 is a 2‐D coordination polymer featuring a layered framework with square cavities. Compound 5 undergoes a reversible single‐crystal‐to‐single‐crystal process, with removal of the solvent molecules (ethyl acetate). The luminescence properties of compounds 5, 7 have been investigated and reveal blue emission with maxima at 402 and 483 nm, respectively. The dynamic magnetic properties and EPR spectrum of 1 have been investigated, revealing the occurrence of slow relaxation of the magnetization that most likely involves a Raman process.