1363261-49-7Relevant articles and documents
Enantioselective synthesis of tryptophan derivatives by a tandem friedel-crafts conjugate addition/asymmetric protonation reaction
Kieffer, Madeleine E.,Repka, Lindsay M.,Reisman, Sarah E.
supporting information; experimental part, p. 5131 - 5137 (2012/05/05)
The 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 SnCl4, and is the first example of a tandem conjugate addition/asymmetric protonation reaction using a BINOLSnCl4 complex as the catalyst. A range of indoles furnished synthetic tryptophan derivatives in good yields and high levels of enantioselectivity, even on a preparative scale. The convergent nature of this transformation should lend itself to the preparation of unnatural tryptophan derivatives for use in a broad array of synthetic and biological applications.