Department of Chemistry, University of California, Berkeley, California, 94720, United States.
J Am Chem Soc. 2011 Mar 16;133(10):3517-27. doi: 10.1021/ja1095045. Epub 2011 Feb 22.
Azlactones participate in stereoselective reactions with electron-deficient alkenes and N-sulfonyl aldimines to give products of 1,3-dipolar cycloaddition and Mannich addition reactions, respectively. Both of these reactions proceed with good to excellent diastereo- and enantioselectivity using a single class of gold catalysts, namely C(2)-symmetric bis(phosphinegold(I) carboxylate) complexes. The development of the azlactone Mannich reaction to provide fully protected anti-α,β-diamino acid derivatives is described. 1,3-Dipolar cycloaddition reactions of several acyclic 1,2-disubstituted alkenes and the chemistry of the resultant cycloadducts are examined to probe the stereochemical course of this reaction. Reaction kinetics and tandem mass spectrometry studies of both the cycloaddition and Mannich reactions are reported. These studies support a mechanism in which the gold complexes catalyze addition reactions through nucleophile activation rather than the more typical activation of the electrophilic reaction component.
氮丙啶酮可以与缺电子的烯烃和 N-磺酰基亚胺进行立体选择性反应，分别得到 1,3-偶极环加成和曼尼希加成反应的产物。这两种反应都可以使用一类金催化剂（即 C(2)对称的双膦金（I）羧酸酯）以良好到优秀的非对映选择性和对映选择性进行。本文描述了氮丙啶酮曼尼希反应的发展，以提供完全保护的反-α,β-二氨基酸衍生物。还考察了几种无环 1,2-二取代烯烃的 1,3-偶极环加成反应以及所得环加成产物的化学性质，以探究该反应的立体化学过程。报道了环加成和曼尼希反应的反应动力学和串联质谱研究。这些研究支持了一种机制，其中金配合物通过亲核试剂的活化而不是更典型的亲电反应组分的活化来催化加成反应。
