Anisotropic Templating Effect in the Formation of Two-Dimensional Anionic Cadmium−Thiocyanate Coordination Solids [(12C4)₂Cd][Cd₂(SCN)₆] and [(12C4)₂Cd][Cd₃(SCN)₈] with Checkerboard and Herringbone Patterns, Respectively

Abstract

This paper reports the syntheses, characterization, and structures of two new two-dimensional cadmium-thiocyanate coordination solids [(12C4)(2)Cd][Cd(2)(SCN)(6)] (1) and [(12C4)(2)Cd][Cd(3)(SCN)(8)] (2), where 12C4 denotes 12-crown-4, C(8)H(16)O(4). 1 crystallizes in a monoclinic unit cell, space group C2/c with lattice parameters a = 16.297(3) Å, b = 26.267(3) Å, c = 16.296(2) Å, beta = 90.20(1) degrees, and Z = 8. 2 crystallizes in a monoclinic unit cell, space group P2(1)/n with lattice parameters a = 11.604(7) Å, b = 11.366(7) Å, c = 15.736(4) Å, beta = 92.84(3) degrees, and Z = 2. The structure of 1 exhibits a two-dimensional tetragonal motif consisting of Cd(2) units arranged in a checkerboard pattern with the dimeric [Cd(2)(SCN)(6)](2)(-) complex as the building block. The crystal structure of 2 can be described as a two-dimensional hexagonal array of linear trimeric Cd(3) units arranged in a herringbone pattern with the [Cd(3)(SCN)(8)](2)(-) complex as the building block. In both 1 and 2, the [(12C4)(2)Cd](2+) dications are housed in cavities within and between the anionic cadmium-thiocyanate layers but with different orientations ("upright" in 1 and "sideways" in 2) with respect to the cadmium-thiocyanate layers, giving rise to an anisotropic templating effect.

Synthesis and characterization of bis[dicarboxylatotetraorganodistannoxane] units involving 5-[(E)-2-(aryl)-1-diazenyl]-2-hydroxybenzoic acids: An investigation of structures by X-ray diffraction, NMR, electrospray ionisation MS and assessment of in vitro cytotoxicity

“…In all four of the structures reported here, the Sn(2)-O(1) and Sn(2)-O(6) distances are almost equal. In a closely related structure with p-fluorophenylacetate ligands [6], the corresponding distances are less symmetrical at 2.498(5) and 2.746(6) Å , respectively, and it was debated as to whether or not the latter contact should be considered as part of the coordination sphere of atom Sn (2). The occurrence of a more symmetrical arrangement in 1 and 4-6 adds weight to the argument for including both interactions in the assessment of the coordination geometry.…”

“…1) where the Sn coordination geometry was skew-trapezoidal bipyramidal [20]. The results of the in vitro cytotoxicity test in human tumour cell lines on compounds 1 and 4 are given as ID 50 values in Table 3 and compared with the data for n Bu 2 Sn(L 2 H) 2 and some compounds that are in current clinical use as antitumour agents. The table clearly shows that compounds 1 and 4 are more active in vitro than n Bu 2 Sn(L 2 H) 2 and most of the standard drugs against all seven human cancer cell lines.…”

“…doi:10.1016/j.jorganchem.2006.08.005 discovery and fabrication of various technologically useful materials [1][2][3][4]. The majority of such species have been constructed from organic ligands and metal ions by spontaneous self-assembly and such assemblies have resulted in a host of intriguing structural topologies and has also extensive application in material science [5].…”

Two-Dimensional Silver-Thiocyanate Layers Directed by Viologens: Structural Transformations upon Low Pressure Stimuli, Piezochromic Luminescence, Photocurrent Responses, and Photocatalytic Properties

“…During the molecular assemblies processes, viologens can serve as steric templates by adjusting their torsion angles defined by two pyridinium rings . Therefore, the use of photoactive viologens as templates can not only obtain sensitive structures, but also bring new functions such as photo-/thermo-/piezo-chromisms to hybrid materials. , As far as the inorganic moiety, halides or pseudohalides of d 10 metals such as Ag­(I) are specially interesting owing to their structural diversities and charming optical/electrical properties. , Among the pseudohalides, SCN – is the most extensively explored owing to its versatile bonding modes, including μ 1 -terminal, μ 2 -bridging (end-on, end-to-end), μ 3 -1,1,3-bridging. , The SCN – -based complexes containing the light transition metals (for example, Cr to Zn) − and actinide­(IV) have been extensively documented. It is worth mentioning that the Ni-SCN/organic cocrystal can be used as a frequency-regulated dielectric switch .…”

Controlling multiple orderings in metal thiocyanate molecular perovskites Ax{Ni[Bi(SCN)6]}

“…1 and ESI Section 3 ‡]. Indeed, for the well studied A + {Cd(NCS) 3 } composition, although changing A results in a wide variety of structures, including ferroelastics and non-linear optical materials, [28][29][30][31][32] only Cs{Cd(NCS 3 )} adopts the perovskite structure. Introducing A-site vacancies allows us to reduce s and thereby stabilise NCSperovskites containing larger organic cations, increasing the range of available orderings.…”