Synthesis, Characterization and Photophysical Properties of Metallopolyynes and Metallodiynes of Platinum(II) with Dibenzothiophene Derivatives

Soluble, thermally stable, and easily processable platinum(II) polyyne polymers of the form trans-[-Pt(PBu3)(2)Ca parts per thousand CRCa parts per thousand C-](n) (R = 2,8-disubstituted dibenzothiophene, 2,8-disubstituted and 3,7-disubstituted dibenzothiophene-S,S-dioxide units) have been prepared in good yields by CuI-catalyzed polymerization involving the dehydrohalogenating coupling of trans-[PtCl2(PBu3)(2)] and HCa parts per thousand CRCa parts per thousand CH. We report their optical absorption and photoluminescence spectra and compare the results with the monomeric model complexes trans-[Pt(Ph)(PEt3)(2)Ca parts per thousand CRCa parts per thousand CPt(Ph)(PEt3)(2)]. The different electronic properties and linkage geometry of the central R group lead to new organometallic materials with distinct photophysical traits. The polymer with more conjugated 3,7-disubstituted dibenzothiophene-S,S-dioxide mainly displays fluorescence band, while its isomer with less conjugated 2,8-disubstituted spacer effectively enhances the intersystem crossing rate and strong phosphorescence emission can be detected even at room temperature.