Schomaker Jennifer M, Toste F Dean, Bergman Robert G
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Org Lett. 2009 Aug 20;11(16):3698-700. doi: 10.1021/ol901542n.
The utility of cobalt dinitrosyl complexes for the [3 + 2] annulation of alkenes with unsaturated enones and ketimines has been demonstrated. Reaction of a series of cobalt dinitrosyl/alkene adducts with conjugate acceptors in the presence of Sc(OTf)(3)/LHMDS formed two new C-C bonds at the carbons alpha to the nitrosyl groups of the substrate, leading to unusual tri- and tetracycles. Retrocycloaddition of these products in the presence of norbornadiene yielded functionalized tetrasubstituted bicyclic olefins.
已证明二亚硝酰钴配合物在烯烃与不饱和烯酮和酮亚胺的[3 + 2]环化反应中的实用性。一系列二亚硝酰钴/烯烃加合物与共轭受体在Sc(OTf)₃/LHMDS存在下反应,在底物亚硝酰基α位的碳上形成了两个新的C-C键,生成了不寻常的三环和四环化合物。这些产物在降冰片二烯存在下进行逆环加成反应,得到了官能化的四取代双环烯烃。