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Updated: Jun 29, 2025
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Synthesis, polymorphism, and shape complementarity-induced co-crystallization of hexanuclear Co(II) clusters capped
Michał Terlecki1, Arkadiusz Kornowicz2, Kornel Sacharczuk1
1Faculty of Chemistry, Warsaw University of Technology, Noakowsiego 3, 00-664 Warsaw, Poland. michal.terlecki@pw.edu.pl.
Abstract:
Polymorphism and co-crystallization have gradually gained attention as new tools in the development of modern crystalline functional materials. However, the study on the selective self-assembly of metal clusters into multicomponent crystals is still in its infancy. Herein, we present the synthesis and characterization of two new heteroleptic hydroxido-acetato and acetato Co(II) clusters [Co6(OH)2(OAc)4(pyret)6] (1) and [Co6(OAc)6(pyret)6] (2) incorporating auxiliary 2-pyrrolidinoethoxylate (pyret) ligands. On this occasion, we revealed that the commonly used thermal procedure for dehydration of cobalt(II) acetate leads to a reagent comprising substantial contamination by cobalt hydroxido moieties. Comprehensive structural analysis of new compounds demonstrated intriguing crystal structure diversity of hydroxido-acetato cluster 1, which represents a rare example of both conformational and packing polymorphism in one compound, originating from the flexibility of organic O,N-ligands in the secondary coordination sphere. Furthermore, both clusters exhibit an interesting propensity for the selective formation of co-crystals 1·2 driven mainly by van der Waals forces and specific shape complementarity between co-formers.
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