Syntheses and structures of two rhenium–sulfur–copper cubane-like cluster compounds with the bridging sulfate anions

Treatment of [Et4N][ReS4] with three equivalents of CuSO4·5H2O in the presence of three equivalents PPh3 gave a tetranuclear cubane-like cluster compound [(μ3-SO4)(μ3-ReS4)Cu3(PPh3)3]·2dmf (1·2dmf) in which a ReS4Cu3 core is capped by a μ3-SO42− moiety, leaving a SO double bond. A similar reaction of [Et4N][ReS4] with three equivalents of CuSO4·5H2O in the presence of two equivalents of PPh3 gave rise to isolation of a neutral one-dimensional polymeric cubane-like cluster compound [(μ4-SO4)(μ3-ReOS3)Cu3(PPh3)2]n (2) in which the ReOS3Cu3 cores are bridged by the μ4-SO42− anions. Both cluster compounds were characterized by single-crystal X-ray diffraction along with the spectroscopic methods.