A new compound derived from Magnus' green salt: solid state structure and evidence for platinum chains in solution

The complex [Pt(NH(2)Eh)(4)][PtCl4], where Eh=2-ethylhexyl, was synthesized and analyzed using various methods. The results imply that [Pt(NH(2)Eh)(4)][PtCl4] forms supramolecular structures composed of chains of platinum atoms not only in the solid state but, most remarkably, also in solution, as indicated by membrane osmometry and viscosimetry. At 37 degreesC in toluene, the chains are present in a worm-like structure and contain ca. 750 platinum atoms on average. The solid state properties of [Pt(NH(2)Eh)(4)][PtCl4] are distinct from those of related compounds with linear 1-aminoalkanes. In particular, [Pt(NH(2)Eh)(4)][PtCl4] is cryochromic and amorphous. The 2-ethylhexyl chains obviously prevent side chain crystallization and, as a consequence, electrostatic interactions between the [Pt(NH(2)Eh)(4)](2+) and [PtCl4](2-) units seem to dominate the structure formation of [Pt(NH(2)Eh)(4)][PtCl4].