PdCl2-NiCl2-PPh3/PVP催化苯乙烯高区域选择性的氢酯化反应

烯烃与CO和醇的催化氢酯化反应是合成竣酸酯的一种简便方法．当烯烃是芳香烯烃时,其产物可用来制备极有价值的非自类解热镇痛抗炎药物ibaprofe。。、naproxen（支链型2一芳基丙酸类）：ArCH。（二。＋CO＋ROH、ArCH（CH。）COOR＋ArCH。CH。COOR＋ArCHfH。toRPd（OAc）。－rnontmorlllonlte－PPh。－HC卜和Pd（OAc）。－PPh。－p－toluenesulfonicacid'惮金属体系在高PPh。／Pd比的PPhs存在下,可高转化率、高选择性地催化芳香烯烃氢酯化反应生成支链酯．近年来高分子负载的双金属体系在选择性加氢"'、加氢脱氯"'中表…

Regioselective Hydroesterification of Styrene Catalyzed by PdCl_2-NiCl_2-PPh_3/PVP

Polymer-supported bimetallic system of PdCl2-4NiCl2-PPH3/PVP PVP= poly(N-vinyl-2-pyrrolidone)] provided an almost regiospecific conversion of styrene to thebranched methyl 2-propionate at a high conversion. Typical reaction conditions are: 353 K,2.1 MPa of CO pressure (gauge pressure), 10h; styrene (1 mmol); methanol (0. 8 mL) ;benzene (10 mL); PdCl2/PVP(0. 04 mmol Pd, N/Pd= 20 in molar ratio); n (Pd): n(Ni): n(PPh3) = 1: 4:1. A remarkable synergic effect of bimetallic catalyst can be observed.Effects of PVP, amount of triphenylphosphine and temperature on the reaction were studied.The system of PdCl2-4NiCl2-PPh3/PVP gave 100% conversion of styrene and 99% selectivityto the branched chain ester under the typical reaction conditions.