Wu Michael H, Hansen Karl B, Jacobsen Eric N
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138 (USA), Fax: (+1) 617-496-1880.
Angew Chem Int Ed Engl. 1999 Jul 12;38(13-14):2012-2014. doi: 10.1002/(SICI)1521-3773(19990712)38:13/14<2012::AID-ANIE2012>3.0.CO;2-H.
The intramolecular cyclization of epoxy alcohols was catalyzed with excellent regio- and enantiocontrol by a [Co(salen)] complex. High endo selectivity was observed for the enantioselective cyclization of terminal epoxy alcohols [Eq. (a)], while the reaction of meso substrates produced novel cyclic and bicyclic ethers in good yields and high enantiopurity. TBME=tert-butyl methyl ether.
[Co(salen)]配合物能以优异的区域和对映选择性催化环氧化醇的分子内环化反应。对于末端环氧化醇的对映选择性环化反应，观察到了较高的内型选择性[式(a)]，而内消旋底物的反应则以良好的产率和高对映体纯度生成了新型的环状和双环醚。TBME = 叔丁基甲基醚。
