Two New Catalysts for the Dehydrogenative Coupling Reaction of Carboxylic Acids with Silanes—Convenient Methods for an Atom‐Economical Preparation of Silyl Esters
作者:Guo‐Bin Liu、Hong‐Yun Zhao、Thies Thiemann
DOI:10.1080/00397910701465669
日期:2007.8
Abstract Tris(triphenylphosphine)cuprous chloride [Cu(PPh3)3Cl] has been found to be an efficient catalyst for the dehydrosilylation of carboxylic acids with silanes. In the presence of 4 mol% Cu(PPh3)3Cl, dehydrosilylation reactions in acetonitrile afforded the corresponding silyl esters at 80°C in good yields. It was noted that triphenylphosphine itself also functions as an adequate catalyst for
obtained by conventional radicalpolymerization of silyl methacrylates followed by simple postreactions. The high isotacticity and insolubility of poly(TTMSSMA) suggested the formation of helical polymers as in the polymerization of similarly bulky triarylmethyl methacrylate. Reversible addition–fragmentation chain-transfer (RAFT) polymerization also worked for these silyl methacrylates, which resulted in
一系列甲硅烷基甲基丙烯酸酯的[CH 2 = C(CH 3)CO 2 SIR 3 ]用不同的甲硅烷基的膨松度[R 3的Si:ME 3的Si,等3的Si中,Me 2吨布丝,我镨3的Si中,Ph 2吨BuSi,Ph 3 Si和(Me 3 Si)3合成[Si]并进行自由基聚合,以有效地制得可溶的聚合物,但高体积的甲基丙烯酸三(三甲基甲硅烷基)甲硅烷基酯(TTMSSMA)除外,这导致了不溶的聚合物。通过酸或氟化物引起的甲硅烷基的脱保护,所有聚合物都可以轻松转化为聚(甲基丙烯酸)(PMAA),并通过与三甲基甲硅烷基重氮甲烷进行甲基化进行甲基化进一步转化为聚甲基丙烯酸甲酯(PMMA),用于分析分子量和战术。立构规整度取决于甲硅烷基取代基的体积。随着体积的增加,全同立构规整度增加。因此,一系列具有各种策略的PMAA和PMMA,从富含间同立构(rr = 74%; Me 2 t BuSi)到无规立构(mr= 50%;i