Reaction of [SNS][AsF6] with Hg(CN)2 and PhHgCN: Preparation and crystal structures of [Hg(CNSNS)2][AsF6]2 and [PhS4N3Ph][AsF6]

Article abstract of DOI:10.1016/0277-5387(95)00426-2

Reaction of Hg(CN)₂ with two equivalents of the salt [SNS][AsF₆] provided a high yield (92%) route to the first metallo-dithiadiazolylium salt, [Hg(CNSNS)₂][AsF₆]₂(I). Its structure and reactivity are compared with those of the analogous organic derivatives, [R.CNSNS][AsF₆]; I initiates the polymerization of tetrahydrofuran and undergoes metathesis reactions but reduction leads to decomposition (forming S₄N₄), whilst oxidation with the halogens provides a novel route to the salts [X.CNSNS][AsF₆] (X = Cl, Br and I). In contrast, reaction of PhHgCN with [SNS][AsF₆] yielded the sulfur-nitrogen chain compound, [PhS₄N₃Ph][AsF₆] (II) with a cation consisting of an alternating S/N chain strung between two phenyl groups.