Enantioselective α-Arylation of Cyclic Ketones Catalyzed by a Combination of an Unmodified Cinchona Alkaloid and a Palladium Complex
作者:Christian Richter、Kalluri V. S. Ranganath、Frank Glorius
DOI:10.1002/adsc.201100669
日期:2012.2
A palladium/Cinchona alkaloid-catalyzed α-arylation between cyclic ketones and aryl halides under phosphine-free conditions is presented. The use of a simple, unmodified Cinchona alkaloid results in high levels of activity and selectivity with up to 93% ee. These enantioinduction levels are comparable or even higher than the ones reported using palladium/BINAP complexes. To the best of our knowledge
提出了在无膦条件下,环酮与芳基卤化物之间钯/金鸡纳生物碱催化的α-芳基化反应。使用简单的未经修饰的金鸡纳生物碱可导致高水平的活性和选择性,ee最高可达93%。这些对映体诱导水平与使用钯/ BINAP复合物所报道的对映体诱导水平相当或什至更高。据我们所知,这代表未修饰的金鸡纳生物碱在不对称过渡金属络合物催化的交叉偶联反应中首次用作配体/催化剂。