Four unprecedented 2D trinuclear Mn(II)-complexes with adenine nucleobase controlled by solvent or co-ligand: Hydrothermal synthesis, crystal structure and magnetic behaviour

• DOI: 10.1016/j.molstruc.2017.11.069
• Publication Date: 2017-11-17T16:30:42Z
• Authors: Hongkun Zhao; Hongming He; Xiuguang Wang; Zhongyi Liu; Bo Ding; Hanwen Yang
• Keywords: SBus; Dimethyl formamide; Adipate

Abstract Four unique infinite 2D Mn(II) aggregates, [Mn 3 ( μ 3 -ade) 2 (OAc) 4 X] n (X = DMF for 1 , DMA for 2 and C 2 H 5 O − for 3 ), [Mn 3 ( μ 3 -ade) 2 (ap) 2 DMF] n ( 4 ) (Hade = adenine; DMF = N , N- dimethylformamide; DMA = N , N- dimethylacetamide, OAc − = acetate ion, H 2 ap = adipic acid) with trinuclear Mn(II) as secondary building units (SBUs), have been successfully synthesized by the assembly of Hade nucleobase and manganese acetate under solvothermal conditions. The resultant complexes can be applied to explore the influence of solvent or co-ligands on the self-assembly and properties of metal complexes based on adenine. The Hade represent tridentate μ 3 -N3, N7, N9 bridging coordination modes. The acetate anions exhibit μ 2 - η 1 :η 1 bidentate, μ 2 - η 1 :η 2 tridentate mode, and μ 2 - η 0 :η 2 bidentate mode. The adipate anions in complex 4 adopt two coordination modes: one is μ 4 - η 2 :η 1 :η 1 :η 1 pentadentate mode, the other one is μ 3 - η 1 :η 2 :η 2 :η 1 hexadentate mode. Their magnetic behaviors exhibit interesting variations, in which the local net magnetization at low temperature increases from 1 to 3 . The Mn II 3 SBUs in 1 – 3 are symmetric with an inversion center, whereas that in 4 has three crystallographically independent Mn II atoms. Thus, the magnetic behaviors of 4 are different from complex 1 – 3 .