Synthesis and Application of Chiral Cyclopropane-Based Ligands in Palladium-Catalyzed Allylic Alkylation
作者:Gary A. Molander、Jason P. Burke、Patrick J. Carroll
DOI:10.1021/jo048782s
日期:2004.11.1
A series of chiral, cyclopropane-based phosphorus/sulfur ligands have been synthesized and evaluated in the palladium-catalyzed allylic alkylation of 1,3-diphenylpropenyl acetate with dimethyl malonate. Variation of the ligand substituents at phosphorus, sulfur, and the carbon backbone revealed 24d to have the optimal configuration for this reaction, giving the product in high yield and with good enantioselectivity
已经合成了一系列手性的,基于环丙烷的磷/硫配体,并在钯催化的1,3-二苯基丙烯基乙酸甲酯与丙二酸二甲酯的钯催化的烯丙基烷基化反应中进行了评估。磷,硫和碳主链上的配体取代基的变化揭示了24d具有该反应的最佳构型,从而以高收率和良好的对映选择性(93%)提供了产物。使用X射线晶体学数据,溶液相NMR研究和产物的绝对立体化学,在现有模型的背景下讨论了观察到的对映选择性的模型。还在钯催化的分子间Heck反应和铑催化的脱氢氨基酸氢化中评估了选定的配体。