Thiophenolate clusters as potential nanosized building blocks for zinc-based nanocomposite materials: synthesis and characterization

The synthesis, the spectroscopic and structural characterization of different thiophenolate-capped zinc clusters are reported and described. In particular, different reactions of 4-chlorobenzenethiol with zinc salts yield the clusters [Me4N][Et3NH][Zn4(mu-S-C6H4-Cl)6(S-C6H4-Cl)4] (2a), [Et3NH]2[Zn4(mu-S-C6H4-Cl)6(S-C6H4-Cl)4] (2b), and [Me4N]2[Zn4(mu-S-C6H4-Cl)6(S-C6H4-Cl)4] (2c), and also the thiophenolate derivative [Et3NH]2[Zn4(mu-S-C6H5)6(S-C6H5)4] (1b) was obtained. The nanosized thiophenolate-capped clusters were investigated by 1H and 13C NMR, elemental analysis, and electrospray ionization (ESI) mass spectrometry. NMR experiments provided insights into the dynamic behaviour of the clusters. The thermal decomposition patterns of 2c were analyzed in air as well as in nitrogen, indicating the formation of zinc oxide and metallic zinc, respectively. The X-ray structure of 2a revealed that the cluster core consists of an adamantane-like framework analogous to those realized in many other M4(SR)10 metal complexes.