Triplet emission in platinum-containing poly(alkynylsilanes)

Synthetic routes to novel oligomeric and polymeric platinum(II)-containing alkynylsilanes were developed. Soluble and thermally stable platinum(II) poly(alkynylsilanes) trans-[-Pt(PBu3)(2)Cequivalent to C(p-C6H4)Cequivalent toCSiPh(2)Cequivalent toC(p-C6H4)Cequivalent toC-](n) were prepared in good yield by CuI-catalyzed condensation polymerization of trans-[PtCl2(PBu3)(2)] with HCequivalent toC(p-C6H4)Cequivalent toCSiPh(2)Cequivalent toC(p-C6H4)Cequivalent toCH. The regiochemical structure of the polymer was studied by NMR (H-1, C-13, Si-29, and P-31) spectroscopy. We report the optical absorption and photoluminescence spectra of such metal-based organosilicon polymer and compare the data with their oligomeric model complexes trans-[Pt(Ph)(PEt3)(2)Cequivalent toC(p-C6H4)Cequivalent toCSiPh(2)Cequivalent to C(p-C6H4)Cequivalent toCPt(Ph)(PEt3)(2)] and trans- [Pt(Ph)(PEt3)(2)Cequivalent toC(p-C6H4)Cequivalent toCSiPh(2)Cequivalent toC(p-C6H4)Cequivalent toCPt(PBu3)(2)Cequivalent toC(p-C6H4)Cequivalent toCSiPh(2)Cequivalent toC(p-C6H4)Cequivalent toCPt(Ph)(PEt3)(2)] Our studies indicate that such organometallic poly(alkynylsilanes) show a strong triplet emission with a very high efficiency of intersystem crossing from the S, singlet excited state to the T, triplet excited state. The dependence of intersystem crossing and the spatial extent of singlet and triplet excitons as a function of the central spacer group is discussed in polymetallaynes possessing SiPh2, C6H4 and Pt(PR3)(2) (R = Et, Bu) linkers. The photoconducting properties of such silicon-linked platinum polyyne are described.