Inducing Platinophilic Interactions in [Pt(SCN)] Salts by Cation Tuning.

A series of simple [Pt(SCN)] salts with a variety of cations was synthesized and characterized using X-ray crystallography to determine factors that could induce platinophilic interactions between [Pt(SCN)] anions, including cation size and shape, charge, and ability to participate in hydrogen bonding. The salts [N(PPh)][Pt(SCN)], [AsPh][Pt(SCN)], and [Co(1,10-phenanthroline)][Pt(SCN)] feature bulky, noncoordinating cations where the [Pt(SCN)] anions are completely separated from each other, with no Pt-Pt interactions present. Salts containing the hydrogen-bonding cations [Co(NH)][Pt(SCN)] and [Co(en)][Pt(SCN)] (en = 1,2-ethylenediamine) display close Pt-Pt distances, with both compounds exhibiting platinophilic interactions with distances of 3.