An Unprecedented Example of Pt_4Ag_3 ClusterFormation: Synthesis and Crystal Structure of [Pt_2(dppy)_4(mu_3-S)_2Ag_3(mu_3-S)_2Pt_2(dppy)_4]~(3+)

摘要

The chemistry of soluble metal - sulfur complexes has been of considerable interest for a number years. Recently, we showed that a tetranuclear d~(10) copper(I) cluster containing a mu_3-sulfido moiety exhibits rich photophysical and photochemical properties. This together with our enormous efforts on the design of luminescent polynuclear d~8 and d~(10)l metal complexes prompted us to extend our studies to polynuclear d~8 metal-sulfur clusters. We report herein on the novel reaction of a dimeric [Pt_2(mu-S)_2(dppy)_4] complex (dppy = 2-diphenylphos-phanopyridine) with silver(I) that gives a heptanuclear het-erometallic complex, which contains a triangular Ag, unit and direct Pt-Ag bonding interactions. Although there have been reports on clusters containing triangular d~(10)-M_3 fragments, those of the coinage metals are mostly held together by polyhydrido complexes of late transition metals. Herein we report the X-ray crystal structure and luminescent behavior of the heptanuclear complex 1, whichcontains a non-hydrido bridged Ag, unit. Furthermore, the synthesis and photophysical behavior of the related letranuclear complex 2 dppm = bis(diphenyl-phosphanolmethane) is also described.