ic9b01140_si_001.pdf (1.28 MB)

Synthesis and Characterization of “Atlas-Sphere” Copper Nanoclusters: New Insights into the Reaction of Cu2+ with Thiols

Download (1.28 MB)
journal contribution
posted on 14.06.2019, 00:00 by Andrew W. Cook, Zachary R. Jones, Guang Wu, Simon J. Teat, Susannah L. Scott, Trevor W. Hayton
Thiolates are a widely used ligand class for the stabilization of M(0)-containing gold and silver nanoclusters. Curiously, though, very few thiolate-stabilized Cu nanoclusters are known. Herein, we report an examination of the reactivity of RSH (R = CH2CH2Ph, n-Bu, n-C12H25) with Cu2+ under anhydrous conditions. These reactions result in the formation of fluorescent “Atlas-sphere”-type copper thiolate nanoclusters, including [Cu12(SR′)6Cl12]­[(Cu­(R′SH))6] (2, R′ = nBu) and [H­(THF)2]2­[Cu17(SR′′)6Cl13­(THF)2(R′′SH)3] (3, R′′ = CH2CH2Ph), which were characterized by X-ray crystallography, electrospray ionization mass spectrometry, NMR spectroscopy, as well as X-ray absorption near-edge structure and extended X-ray absorption fine structure (EXAFS) spectroscopies. Consistent with our X-ray crystallographic results, the edge energies of 2 and 3 suggest they are constructed exclusively with Cu­(I) ions. Similarly, EXAFS of 2 and 3 reveals long Cu–Cu pathlengths, which is also consistent with their X-ray crystal structures. Given these results, as well as past work on Cu2+/thiol reactivity, we suggest that Cu(0) is unlikely to be formed by the reaction of Cu2+ with a thiol and that previous reports of Cu(0)-containing nanoclusters synthesized by reaction of Cu2+ with thiols are likely erroneous.