Synthesizing 2D and 3D Selenidostannates in Ionic Liquids: The Synergistic Structure-Directing Effects of Ionic Liquids and Metal-Amine Complexes

Presented are the ionothermal syntheses, characterizations, and properties of a series of two- and three-dimensional selenidostannate compounds synergistically directed by metal-amine complex (MAC) cations and ionic liquids (ILs) of [Bmmim]Cl (Bmmim=1-butyl-2,3-dimethylimidazolium). Four selenidostannates, namely, 2D-(Bmmim)₃[Ni(en)₃]₂[Sn₉Se₂₁]Cl (1, en=ethylenediamine), 2D-(Bmmim)₈[Ni₂(teta)₂(μ-teta)]Sn₁₈Se₄₂ (2, teta=triethylenetetramine), 2D-(Bmmim)₄[Ni(tepa)Cl]₂[Ni(tepa)Sn₁₂Se₂₈] (3, tepa=tetraethylenepentamine), and 3D-(Bmmim)₂[Ni(1,2-pda)₃]Sn₈Se₁₈ (4, 1,2-pda=1,2-diaminopropane), were obtained. Single-crystal X-ray diffraction analyses revealed that compounds 1 and 2 possess a lamellar anionic [Sn₃Se₇]_n^2n- structure comprising distinct eight-membered ring units, whereas 3 features a MAC-decorated anionic [Ni(tepa)Sn₁₂Se₂₈]_n^6n- layered structure. In contrast to 1-3, compound 4 exhibits a 3D open framework of anionic [Sn₄Se₉]_n^2n-. The structural variation from 1 to 4 clearly indicates that on the basis of the synergistic structure-directing ability of the MACs and ILs, variation of the organic polyamine ligand has a significant impact on the formation of selenidostannates. MAC it happen: Presented is a study of the synergistic structure-directing effect of metal-amine complexes (MACs) with different chelating polyamine ligands and imidazolium-based ionic liquid (IL) cations. For the first time, a layered selenidostannate with an asymmetric eight-membered ring, an organic-decorated layered selenidostannate, and a 3D selenidostannate with both the MAC and IL cations as structure-directing agents and counterions are obtained. en=ethylenediamine, teta=triethylenetetramine, tepa=tetraethylenepentamine, 1,2-pda=1,2-diaminopropane.