New Coordination Polymers of Zinc(II), Copper(II) and Cadmium(II) with 1,3-Bis(1,2,4-triazol-4-yl)adamantane

Abstract

The new coordination polymers (CPs) [Zn(tr2ad)Cl2]n, {[Cu(tr2ad)Cl]Cl∙4H2O}n, [Cd2(tr2ad)Cl4]n, {[Cu(tr2ad)(NO3)](NO3)}n and {[Cd(tr2ad)(NO3)](NO3)∙H2O}n were obtained in the form of air- and moisture-stable microcrystalline powders by the solvothermal reactions of zinc(II), copper(II) and cadmium(II) chlorides or nitrates with the ligand 1,3-bis(1,2,4-triazol-4-yl)adamantane (tr2ad). Investigation of the thermal behaviour assessed the thermal stability of these CPs, with [Cd2(tr2ad)Cl4]n starting to decompose only around 365 °C. As retrieved by powder X-ray diffraction, while [Zn(tr2ad)Cl2]n features 1-D chains along which the metal centre shows a tetrahedral geometry and the spacer is exo-bidentate, the other CPs contain 2-D double-layers in which the metal ions possess an octahedral stereochemistry and the linker is exo-tetradentate. A comparative structural analysis involving known coordination compounds containing the tr2ad ligand enabled us to disclose (i) the versatility of the ligand, as far as the coordination modes are concerned; (ii) the variability in crystal structure dimensionality, ranging from 1-D to 3-D; (iii) the fact that, to the best of our knowledge, [Zn(tr2ad)Cl2]n is the first ZnII-based CP containing the tr2ad spacer.

Synthesis, Crystal Structure, and Luminescence of Cadmium(II) and Silver(I) Coordination Polymers Based on 1,3-Bis(1,2,4-triazol-1-yl)adamantane

“…Coordination polymers and metal-organic frameworks in particular are promising materials with a wide range of potential applications-gas storage and separation [11,12], enantioselective catalysis [13,14], supramolecular systems design [15], pollutant sensing [16,17], water purification [18], fabrication of electrochemical devices [19,20], and biological activity [21]. Coordination polymers based on 1,3-bis(1,2,4-triazol-4-yl)adamantane with Mo(IV), Cu(II), Zn(II), Cd(II), Ag(I), bimetallic Ag(I)/V(V), and Cu(II)/Mo(IV) were successfully synthesized and characterized by Domasevitch research group [22][23][24][25][26][27][28][29][30][31], but the coordination chemistry of its isomer, 1,3-bis(1,2,4-triazol-1-yl)adamantane remained unexplored.…”