Abstract
The synthesis and a detailed reactivity study of a binuclear zinc(II) bis(benzenethiolate) complex, [Zn2(BPMP)(SPh)2]+ (4), and an unprecedented binuclear zinc(II) pentasulfido complex, [Zn2(BPMP)(μ2-S5)]+ (6), are presented. While one-electron oxidation of the coordinated benzenethiolate ligands in 4 by Cp2Fe+ produces diphenyl disulfide and [Zn2(BPMP)(μ2-OH)]2+ (5), a two-electron redox reaction between coordinated benzenethiolate ligands in 4 and elemental S (S8) generated diphenyl disulfide and the binuclear zinc(II) pentasulfido complex 6. Complex 6 features a chelating, dianionic, pentasulfido (S52-) chain and can consume up to a maximum of 3 equiv of PPh3 to generate Ph3PS and 5, while the reaction of 6 with 1 equiv of diphenylphosphinoethane allowed the isolation of [Zn2(BPMP)(μ2-S4)]+ (7). A proteolysis reaction of the coordinated S52- chain in 6 with fluoroboric acid (HBF4), benzoic acid (PhCOOH), and thioacetic acid (MeCOSH) generates the complexes [Zn2(BPMP)(MeCN)2]3+ (1), [Zn2(BPMP)(μ2-PhCOO)2]+ (8), and [Zn2(BPMP)(μ2-SCOMe)2]+ (9), respectively, while the protonated S52- chain liberates S8 and hydrogen sulfide (H2S). Finally, the transfer of the coordinated benzenethiolate ligands in 4 and the S52- chain in 6 to selected organic compounds, namely, PhCH2Br and PhC(O)Cl, for the generation of various organosulfur compounds is demonstrated.
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