Activated dihydridocarbonyltris(triphenylphosphine)ruthenium (Ru) catalyzes the dehydrogenative silylation condensation copolymerization of o-quinones with alpha,omega -dihydridooligodimethylsiloxanes to give high molecular weight copoly(arylene-1,2-dioxy/oligodimethylsiloxanylene)s in good chemical yield. These copolymers have been characterized by H-1, C-13, and Si-29 NMR as well as IR and UV. Their molecular weight distributions (M-w/M-n) have been determined by GPC. Their thermal stability was measured by TGA, and their glass transition temperatures (T(g)s) were determined by DSC. The photoluminescence properties of the copolymers were studied along with those of two model compounds. The decrease in T(g)s with increase in siloxane chain length as well as fluorescence spectra will be discussed. A mechanism of the copolymerization is proposed, in which, for these substrates, beta -hydride elimination is favored over reductive elimination.