Shang J.-Y.,Hangzhou NormalUniversity |
Li F.,Hangzhou NormalUniversity |
Bai X.-F.,Hangzhou NormalUniversity |
Jiang J.-X.,Hangzhou NormalUniversity |
And 3 more authors.
European Journal of Organic Chemistry | Year: 2012
A very simple, direct, bismuth-catalyzed conjugate reduction protocol that allows for the catalytic regioselective formation of substituted ketones from enones under mild conditions has been developed. We have shown for the first time that the combined poly(methylhydro)siloxane-malononitrile system can serve as an efficient reductant/reagent in 1,4-conjugate reduction of enones. The regioselectivity, efficiencies, and experimental simplicity of the present method complements the more complex methods previously employed in copper or palladium-catalyzed reduction. This method should prove attractive because of its mild reaction conditions and the interesting chemistry of combining the use of poly(methylhydro)siloxane and malononitrile for selective reduction. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zhang X.,East China University of Science and Technology |
Wang C.,East China University of Science and Technology |
Lai G.,Hangzhou NormalUniversity |
Zhang L.,East China University of Science and Technology |
Shen Y.,East China University of Science and Technology
New Journal of Chemistry | Year: 2010
A series of conjugated ethynylene-fluorene polymers with electro-donating TTF as pendant groups (P2-P4) were synthesized by using Sonogashira coupling reaction, and two functionalization methods, i.e. prepolymerization and postpolymerization, were developed. The composition and purity of the corresponding products were analyzed by 1H NMR. The results proved the functionalization of P2 (pre) and P2 (post) were 40% and 100%, respectively. The results also indicated that the postpolymerization method would be a better approach to prepare TTF-pendant conjugated ethynylene-fluorene polymers. The postpolymerization methodology could be extended to synthesize other conjugated fluorene-based polymers bearing TTF units (P3 and P4). The polymers mentioned above exhibited good solubility in normal organic solvents and higher conductivity (neutral conductivity ∼2-4 × 10-6 S cm -1; doped conductivity ∼1-3 × 10-3 S cm -1). Moreover, the fluorescence intensity of P2 (post) could be modulated by the oxidation of TTF units, which makes it an attractive candidate for the fluorescence switch. © 2010 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.