Base-Promoted Synthesis of β-Substituted-Tryptophans via a Simple and Convenient Three-Component Condensation of Nickel(II) Glycinate

Abstract

A three-component reaction of nickel(II) glycinate was conducted for the convenient synthesis of β-substituted-tryptophans. The reaction worked smoothly under mild conditions and the procedure was simple and easy to handle.

Asymmetric Synthesis of Tailor-Made Amino Acids Using Chiral Ni(II) Complexes of Schiff Bases. An Update of the Recent Literature

“…While our aim was to present as comprehensive treatment of the subject as possible, we eventually missed some of the relevant data that were kindly pointed to us during the profound and very thoughtful refereeing of this work. These include Michael additions of chiral glycine Schiff base Ni(II)-complex with 1-(1-phenylsulfonyl)benzene [124], synthesis of β-substituted-tryptophans via three-component reactions of glycine Ni(II)-complex [125], synthesis of β-substituted α,γ-diaminobutyric acid derivatives via Michal addition reactions [126] and an approach to γ-amino acids via Ni-catalyzed carbodifunctionalization of N-vinylamides [127]. Besides, novel application of amino acids in functional supramolecular materials [128,129] might also be of interest.…”

“…They synthesized ten complexes with variations of amino group, substitution on o-amino-benzophenone and transition-metal by using of the similar method reported previously. Generally, Cu(II) complex is obviously less stable as compared with Ni(II) and Pd(II); the N-methylamine-based complex (127) is more stable than those with N-H type complexes (125,126).…”