Catalytic enantioselective synthesis of indolizino[8,7-b]indole alkaloid derivatives based on the tandem reaction of tertiary enamides

An exquisite catalytic asymmetric tandem reaction of tertiary enamides catalyzed by a chiral Diph-Pybox/Cu(OTf)(2) complex was developed. The method, which comprised an enantioselective intramolecular addition of tertiary enamides to ketonic carbonyls followed by the diastereoselective interception of acyliminium by a tethered indole moiety, enables the expeditious synthesis of indolizino[8,7-b]indole derivatives with high yields, and excellent enantioselectivity and diastereoselectivity.

Automated summary

A novel catalytic asymmetric tandem reaction of tertiary enamides was developed using a chiral Diph-Pybox/Cu(OTf)(2) complex. The method allows for the expedited synthesis of indolizino[8,7-b]indole derivatives with high yields and excellent enantioselectivity and diastereoselectivity.