Direct Catalytic Asymmetric Aldol Reaction of Hydroxyketones: Asymmetric Zn Catalysis with a Et<sub>2</sub>Zn/Linked-BINOL Complex
作者:Naoya Kumagai、Shigeki Matsunaga、Tomofumi Kinoshita、Shinji Harada、Shigemitsu Okada、Shigeru Sakamoto、Kentaro Yamaguchi、Masakatsu Shibasaki
DOI:10.1021/ja028926p
日期:2003.2.1
are described. A Et(2)Zn/(S,S)-linked-BINOL complex was developed and successfully applied to direct catalytic asymmetric aldol reactions of hydroxyketones. A Et(2)Zn/(S,S)-linked-BINOL 1 = 2/1 system was initially developed, which efficiently promoted the direct aldol reaction of 2-hydroxy-2'-methoxyacetophenone (7d). Using 1 mol % of (S,S)-linked-BINOL 1 and 2 mol % of Et(2)Zn, we obtained 1,2-dihydroxyketones
描述了我们新开发的具有不对称锌络合物作为II类含锌醛缩酶模拟物的催化剂的全部细节。Et(2)Zn /(S,S)-联-BINOL复合物被开发并成功地用于直接催化羟基酮的不对称羟醛羟醛反应。最初开发了Et(2)Zn /(S,S)-linked-BINOL 1 = 2/1系统,该系统有效地促进了2-羟基-2'-甲氧基苯乙酮的直接羟醛反应(7d)。使用1 mol%的(S,S)-连接的BINOL 1和2 mol%的Et(2)Zn,我们以高收率(最高95%),良好的非对映异构体比例(1,2-二羟基酮)选择性合成。高达97/3)和出色的对映体过量(高达99%)。Et(2)Zn /(S,S)-联苯酚1的机理研究,包括X射线分析,NMR分析,冷喷雾电离质谱(CSI-MS)分析和动力学研究,提供了对活性低聚物Zn /(S,S)-连接的BINOL 1 /酮7d活性物种的新见解。在机理研究的基础上,开发了具有分子筛3A(MS