Department of Chemistry, University of California, Berkeley, California 94720, USA.
J Am Chem Soc. 2011 Apr 13;133(14):5500-7. doi: 10.1021/ja200084a. Epub 2011 Mar 23.
In this article the utility of phosphoramidite ligands in enantioselective Au(I) catalysis was explored in the development of highly diastereo- and enantioselective Au(I)-catalyzed cycloadditions of allenenes. A Au(I)-catalyzed synthesis of 3,4-disubstituted pyrrolidines and γ-lactams is described. This reaction proceeds through the enantioselective Au(I)-catalyzed cyclization of allenenes to form a carbocationic intermediate that is trapped by an exogenous nucleophile, resulting in the highly diastereoselective construction of three contiguous stereogenic centers. A computational study (DFT) was also performed to gain some insight into the underlying mechanisms of these cycloadditions. The utility of this new methodology was demonstrated through the formal synthesis of (-)-isocynometrine.
本文探讨了膦酰胺配体在立体选择性 Au(I)催化中的应用，用于开发高度非对映选择性和对映选择性的 Au(I)催化的allenene 环加成反应。描述了一种 Au(I)催化的 3,4-二取代吡咯烷和 γ-内酰胺的合成方法。该反应通过对烯丙进行对映选择性 Au(I)催化环化形成碳阳离子中间体，然后被外源性亲核试剂捕获，从而高度非对映选择性地构建三个连续的立体中心。还进行了计算研究（DFT）以深入了解这些环加成反应的潜在机制。该新方法的实用性通过（-）-异环宁的形式合成得到了证明。
