Pham Phong V, Ashton Kate, Macmillan David W C
Merck Center for Catalysis at Princeton University, Princeton, New Jersey, 08544, USA; ; Tel: +1 609 2582254.
Chem Sci. 2011 Aug 1;2(8):1470-1473. doi: 10.1039/C1SC00176K. Epub 2011 May 19.
The intramolecular asymmetric cyclization of aldehydes has been accomplished using singly occupied molecular orbital (SOMO) catalysis. Selective oxidation of chiral enamines (formed by the condensation of an aldehyde and a secondary amine catalyst) leads to the formation of a 3π-electron radical species. These chiral SOMO-activated radical cations undergo enantioselective cyclization with an array of pendent allylsilanes thus efficiently providing a new approach to the construction of five-, six- and seven-membered carbocycles and heterocycles.
醛的分子内不对称环化反应已通过单占据分子轨道(SOMO)催化实现。手性烯胺(由醛与仲胺催化剂缩合形成)的选择性氧化导致形成一个3π电子自由基物种。这些手性SOMO活化的自由基阳离子与一系列侧链烯丙基硅烷发生对映选择性环化反应,从而有效地提供了一种构建五元、六元和七元碳环及杂环的新方法。