| Novel materials based on dihydridocarbonyltris(triphenylphosphine)ruthenium [RuH2CO(PPh3)3] catalysis are presented. Polymers containing alternating aromatic ketone and tetramethyldisiloxane units have been synthesized and their properties investigated. This catalytic system has also been used to construct novel cross-conjugated polymers.;We have prepared 1-beta-(4'-acetylstyrenyl)-3-vinyl-1,1,3,3-tetramethyldisiloxane) and AB2 monomer, by a palladium catalyzed Heck reaction of 4-bromoacetophenone with 1,3-divinyl-1,1,3,3-tetramethyldisiloxane. Polymerization of this monomer in the presence of a catalytic amount of RuH2CO(PPh3) 3 yields a hyperbranched material. We have investigated the thermal properties of this material.;RuH2CO(PPh3)3 catalyzed copolymerization of benzophenone and 1,3-divinyltetramethyldisiloxane leads to a mixture of 5,6,8,9-dibenzo-2,2,12,12-tetramethyl-1-oxa-2,12-disilacyclododecan-7-one (I) and random copoly(2,2'-benzophenonylene alt. 2,6-benzophenonylene/3,3,5,5-tetramethyl-4-oxa-3,5-disila-1,7-heptanylene) (I-ip). The ratio of I to I-ip is concentration dependent. Triflic acid catalyzed ring opening polymerization of I yields copoly(2,2'-benzophenonylene/3,3,5,5-tetramethyl-4-oxa-3,5-disila-1,7-heptanylene) (I-rp).;RuH2CO(PPh3)3 catalyzed copolymerization of acetophenone and 1,4-bis(trimethylsilylethynyl)benzene yields copoly[2-acetyl-1,3-phenylene/alpha,alpha'- bis(trimethylsilylmethylene)-1,4-xylenylene]. Similar ruthenium catalyzed reaction of 4-(trimethylsilylethynyl)acetophenone yields a hyperbranched material. Both of these cross-conjugated unsaturated materials have regularly alternating arylene and 1,1-vinylene units. These materials are characterized by their blue fluorescence.;In particular, 4'-substituted acetylstilbene derivatives have been synthesized using Palladium (Heck) coupling reactions between p-bromoacetophenone and various substituted styrenes. When copolymerized with divinyltetramethyldisiloxane, these acetylstilbene derivatives give a siloxane copolymer with a donor/acceptor chromophore in the polymer backbone. Thus, this methodology enables one to construct a polymer containing a non-linear optical chromophore which is in the main chain of the chromophore.;The free radical polymerization of 7-methyl-1-methylene-3-phenylindene yields copoly(methylene/7-methyl-3-phenyl-1,1-indenylene) (V). This novel copolymer has an aliphatic backbone and pendant cross-conjugated 1,1-diphenylethylene chromophores. Due to the close proximity of neighboring chromophores, excimer formation is observed at 450 nm, even in dilute solution. A thin film of V shows a high-energy excimer at 390 nm, as well as monomer emission at 340 and excimer emission at 456 nm. 3-Phenylindene (I), which serves as a monomeric model compound, shows only monomer emission at 348 nm in dilute solution. The monomer, excimer and high-energy excimer are detected in a thin film of I. |
