Conjugated Copolymers That Shouldn't Be

Multiple studies have explored using cage silsesquioxanes (SQs) as backbone elements in hybrid polymers motivated by their well-defined structures and physical mechanical properties. As part of this general exploration, we report unexpected photophysical properties copolymers derived from divinyl double decker (DD) SQs, [vinyl(Me)Si(O0.5)2][PhSiO1.5]8[(O0.5)2Si(Me)vinyl] (vinylDDvinyl). These exhibit strong emission red-shifts relative to model compounds, implying unconventional conjugation, despite vinyl(Me)Si(O-)2 siloxane bridges. In an effort identify minimum SQ that do/do not offer extended Heck catalyzed co-polymerization vinyl-ladder(LL)-vinyl vinyl(Me/Ph)Si(O0.5)2[PhSiO1.5]4(O0.5)2Si(Me/Ph)vinyl, with Br-Ar-Br. Most surprising, the resulting oligomers show 30–60 nm beyond those seen vinylDDvinyl analogs lacking a true cage. Further evidence for conjugation includes apparent integer charge transfer (ICT) between LL-co-thiophene, bithiophene, thienothiophene 10 mol % F4TCNQ, suggesting potential p-type doped organic/inorganic semiconductors.