Asymmeric Formal [3 + 3]-Cycloaddition Reactions of Nitrones with Electrophilic Vinylcarbene Intermediates
作者:Xiaochen Wang、Xinfang Xu、Peter Y. Zavalij、Michael P. Doyle
DOI:10.1021/ja207664r
日期:2011.10.19
With metal carbene access to dipolar intermediates, 3,6-dihydro-1,2-oxazines are produced in high yields by dirhodium(II) carboxylate catalyzed reactions between nitrones and a β-TBSO-substituted vinyldiazoacetate. High enantiocontrol occurs with catalysis by N-phthaloyl-(S)-(amino acid)-ligated dirhodium carboxylates for [3 + 3]-cycloaddition reactions with both acyclic and cyclic nitrones.
随着金属卡宾进入偶极中间体,3,6-二氢-1,2-恶嗪通过羧酸二铑 (II) 催化硝酮和 β-TBSO 取代的重氮乙酸乙烯酯之间的反应以高产率生产。N-邻苯二甲酰基-(S)-(氨基酸)-连接的羧酸二铑催化与无环和环状硝酮进行[3 + 3]-环加成反应,发生高对映控制。