A chemically induced, room temperature, single source precursor to CuS (covellite) nanomaterials: synthesis and reactivity of [Cu(S2CNHBz)]n

Abstract

Addition of two equivalents of NaS₂CNHBz to CuSO₄ affords the yellow diamagnetic coordination polymer [Cu(S₂CNHBz)]_n (1), resulting from intramolecular electron-transfer and concomitant formation of the thiourea, (BzNH)₂CS. 1 reacts with PPh₃ and 1,1′-bis(diphenylphosphino)ferrocene (dppf) in CH₂Cl₂ to give monomeric [Cu(κ²-S₂CNHBz)(PPh₃)₂] (2) and [Cu(κ²-S₂CNHBz)(κ²-dppf)] (3), respectively, both of which have been crystallographically characterised. While 1 is thermally stable in dimethylsulfoxide (DMSO) up to ca. 70 °C, addition of ⁿBuNH₂ to 1 leads to its rapid decomposition to afford CuS (covellite) nanomaterials; indeed in neat ⁿBuNH₂, covellite formation is rapid at room temperature. Thus, 1 serves as an effective low-temperature base-induced single source precursor to covellite nanomaterials.