120238-42-8Relevant articles and documents
Catalytic Dehydrogenative β-Alkylation of Amino Acid Schiff Bases with Hydrocarbon
Ikeda, Tetsu,Ochiishi, Haruka,Yoshida, Mana,Yazaki, Ryo,Ohshima, Takashi
supporting information, p. 369 - 373 (2022/01/04)
A synthetic method for the synthesis of a highly congested α,β-dehydroamino acid through the β-C–H bond activation of an amino acid Schiff base is described. Abundant hydrocarbon feedstock could be used as an alkylating reagent to afford an α,β-dehydroamino acid bearing a quaternary carbon at the γ-position with an exclusively (Z)-geometry. Notably, a tetrasubstituted olefin could be constructed from saturated starting materials. The transformation of the synthesized α,β-dehydroamino acid into unnatural α-amino acid derivatives was also demonstrated.
Amino Acid Schiff Base Bearing Benzophenone Imine As a Platform for Highly Congested Unnatural α-Amino Acid Synthesis
Matsumoto, Yohei,Sawamura, Jun,Murata, Yumi,Nishikata, Takashi,Yazaki, Ryo,Ohshima, Takashi
supporting information, p. 8498 - 8505 (2020/05/18)
Unnatural α-amino acids are invaluable building blocks in synthetic organic chemistry and could upgrade the function of peptides. We developed a new mode for catalytic activation of amino acid Schiff bases, serving as a platform for highly congested unnatural α-amino acid synthesis. The redox active copper catalyst enabled efficient cross-coupling to construct contiguous tetrasubstituted carbon centers. The broad functional group compatibility highlights the mildness of the present catalysis. Notably, we achieved successive β-functionalization and oxidation of amino acid Schiff bases to afford dehydroalanine derivatives bearing tetrasubstituted carbon. A three-component cross-coupling reaction of an amino acid Schiff base, alkyl bromides, and styrene derivatives demonstrated the high utility of the present method. The diastereoselective reaction was also achieved using menthol derivatives as a chiral auxiliary, delivering enantiomerically enriched α-amino acid bearing α,β-continuous tetrasubstituted carbon. The synthesized highly congested unnatural α-amino acid could be derivatized and incorporated into peptide synthesis.
Investigations concerning the syntheses of TADDOL-derived secondary amines and their use to access novel chiral organocatalysts
Gratzer, Katharina,Waser, Mario
supporting information, p. 3661 - 3670 (2013/02/22)
A structurally carefully diversified library of novel TADDOL-derived chiral secondary amines was synthesized and investigated for their applicability to obtain new organocatalysts like chiral Lewis bases and chiral phase-transfer catalysts. The scope and limitations of the developed syntheses routes to access these catalysts as well their catalytic performance in different benchmark reactions were systematically investigated. The most powerful of the catalysts prepared was found to be highly useful for the phase-transfer catalyzed α-alkylation of glycine Schiff base (high yields and up to 93% ee). Georg Thieme Verlag KG Stuttgart · New York.
