Halogen as Template to Modulate the Structures of the Nanocage-Based Silver(I)-Thiolate Coordination Polymers

TL;DR

This paper shows how different halogen ions can control the structure of silver-thiolate coordination polymers.

Contribution

The study reveals how halogen ion size influences the formation of nanocage-based silver-thiolate structures.

Findings

Fluoride and chloride lead to one-dimensional Ag6-cage structures without halogen encapsulation.

Bromide and iodide produce distinct chain-like structures with encapsulated halogens in silver cages.

Halogen templates guide the nucleation and structural evolution of silver-thiolate clusters.

Abstract

By the reaction of AgNO3, 2-methyl-2-propanethiol (HStBu), with various-sized halogen ions as templates, three multi-nuclear silver-thiolate cluster-based chain-like coordination polymers, [Ag6(μ-SBu)6]n (USC-CP-2), [Ag6(μ-StBu)5Br]n (USC-CP-4) and [Ag14(μ-StBu)12I2]n (USC-CP-3) constructed by different Ag(I)-nanocages, have been synthesized and characterized by X-ray diffraction analyses. With F−, Cl− or without template, USC-CP-2 exhibits a one-dimensional structure composed of detached Ag6-cages, absent of fluoride or chloridion. While with Br− and I−, USC-CP-4 and USC-CP-3, two distinct halogen-templating multi-sliver cages-based chain-like polymeric structures have been observed, which are a mono-Br− encapsulated Ag8-cage, or a dual-I− embedded Ag16-cage, respectively. In these three compounds, the multi-Ag(I) cages were self-assembled by Ag-S bonds through bridged μ2-StBu ligands, and stabilized argentophilic interactions between neighboring silver atoms. This study demonstrates that the halide anions of varying sizes play a critical role in inducing the nucleation and structural evolution of the silver-thiolate clusters.

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