Preparation and catalytic properties of immobilized chiral dirhodium(II) carboxamidates
Preparation and catalytic properties of immobilized chiral dirhodium(II) carboxamidates
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DOI：
10.1021/om011082i
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发表时间：
2002-04-29
期刊：
影响因子：
2.8
通讯作者：
Blossey, EC
中科院分区：
文献类型：
--
作者：
Doyle, MP;Timmons, DJ;Blossey, EC
用聚苯乙烯-聚乙二醇和梅里菲尔德树脂固定了手性二铑（11）四[2-氧代吡咯烷-5（S）-羧酸甲酯]。这些催化剂的分子内和分子间环丙烷化反应表现出其高选择性，与其均相对应物相当或更好，并且已经实现了回收和重复使用多达9个连续应用而不损失选择性。催化剂稳定性与配体所附着的可用位点的百分比有关，但聚合物上与铑（11）结合的配体位点的百分比似乎不影响稳定性或选择性。
Chiral dirhodium(11) tetrakis[methyl 2-oxypyrrolidine-5(S)-carboxylate] has been immobilized on polystyrene-poly(ethylene glycol) and Merrifield resins. Intra- and intermolecular cyclopropanation reactions with these catalysts demonstrate their high selectivity, comparable to or better than their homogeneous counterpart, and recovery and reuse for up to nine sequential applications have been achieved without loss of selectivity. Catalyst stability is related to the percentage of available sites to which the ligand is affixed, but the percentage of ligand sites on the polymer that are bound to dirhodium(11) does not appear to influence stability or selectivity.