(聚酰胺-胺)-水杨醛席夫碱树枝状大分子钯配合物的合成、表征及催化性能

Synthesis,Characterization and Catalytic Performance of PAMAM-Salicylidene Schiff Base Dendrimer Palladium Complex

首先通过发散法合成出1.0G～5.0G聚酰胺-胺树枝状大分子PAMAM;然后利用氨基与醛的脱水缩合反应,用水杨醛对大分子进行修饰合成出(聚酰胺-胺)-水杨醛席夫碱树枝状大分子配体PAMAMSA;再通过PAMAMSA与氯钯酸锂在甲醇中反应制得一系列钯配合物PAMAMSA-Pd.用红外光谱、核磁共振谱、热重-差热法对所合成的材料结构组成进行了表征与确证.研究了在纯水介质中PAMAMSA-Pd作为催化剂前躯体对碘代苯及其衍生物与丙烯酸Heck交叉偶联反应的催化性能,并比较了钯配合物和PdCl2的催化活性,结果表明树枝状大分子催化剂显示出良好的催化活性,其中1.0G PAMAMSA-Pd和5.0G PAMAMSA-Pd的活性较高.

First,1.0G～5.0G polyamidoamine dendrimers（PAMAM） were synthesized by divergent ap-proach.Then the PAMAM were modified with salicylaldehyde by the dehydration condensation reaction of amino and aldehyde,and the Schiff base ligands（PAMAMSA） were prepared successfully.Finally,a series of PAMAMSA palladium complexes were synthesized by the reaction of Schiff base with Li2PdCl4 in methanol.The structures and components of PAMAMSA-Pd were confirmed by the characterization of FT-IR,elemental analysis and TG-DSC.Using PAMAMSA-Pd as catalyst precursor,the catalytic perform-ances were evaluated in the Heck cross-coupling of iodobenzene（or its derivatives） with acrylic acid in neat water medium.The dendrimer catalyst showed higher activity comparing to PdCl2.The 1.0G PAMAMSA-Pd and 5.0G PAMAMSA-Pd were found to have the higher activity in the Heck reaction.