Enantioselective Synthesis of Tryptophan Derivatives by a Tandem Friedel–Crafts Conjugate Addition/Asymmetric Protonation Reaction
作者:Madeleine E. Kieffer、Lindsay M. Repka、Sarah E. Reisman
DOI:10.1021/ja209390d
日期:2012.3.21
tandem Friedel-Crafts conjugate addition/asymmetric protonation reaction between 2-substituted indoles and methyl 2-acetamidoacrylate is reported. The reaction is catalyzed by (R)-3,3'-dibromo-BINOL in the presence of stoichiometric SnCl(4), and is the first example of a tandem conjugate addition/asymmetric protonation reaction using a BINOL·SnCl(4) complex as the catalyst. A range of indoles furnished