Recently，important progress in catalytic asymmetric synthesis of chiral [n.3.1] compounds has been made by Dr. Xiangping Hu of DICP and his co-workers, and their results were introduced by the “JACS Spotlights” column in the newly appearing Journal of American Chemical Society （J. Am. Chem. Soc. 2012, 134, 9585-9588）.
In this study, by employing proprietarily developed chiral tridentate P,N,N-ligands, the DICP researchers were able to realize for the first time an asymmetric [3+3] cyclic-addition reaction of propargyl alcohol easters with cyclic enamines over copper based catalysts, thus provided a concise, highly efficient and highly stereoselective route for the building of chiral bicyclic [n.3.1] frameworks.
A comment with the title of “Copper Eases the Way to Building Bicyclic Compounds” was given on the JACS Spotlights page, which highly evaluated the significance of this work in researches of complex compound systems with optically active bicyclic [n.3.1] frameworks as well as in the studies of corresponding active natural products.