Highly regioselective Lewis acid-catalyzed [3+2] cycloaddition of alkynes with donor–acceptor oxiranes by selective carbon–carbon bond cleavage of epoxides
Nickel-Catalyzed Annulation of Donor-Acceptor Oxiranes with Imines: Diastereoselective Access to Highly Substituted 2,4-<i>trans</i>-Oxazolidines
作者:Junqing Zhang、Yuanjing Xiao、Junliang Zhang
DOI:10.1002/adsc.201300449
日期:2013.10.11
AbstractAn efficient approach for the synthesis of highly substituted 2,4‐trans‐oxazolidines has been achieved by means of nickel(II) chlorate hexahydrate [Ni(ClO4)2⋅6 H2O]‐catalyzed [3+2] dipolar cycloaddition reactions of donor–acceptor oxiranes with imines via CC bond cleavage in good yields with moderate to high diastereoselectivity. The appropriate orientation of two activating ketones or esters is crucial for this chemoselective CC bond cleavage of the oxirane ring.magnified image