126535-86-2Relevant articles and documents
A Broad Substrate Scope of Aza-Friedel-Crafts Alkylation for the Synthesis of Quaternary α-Amino Esters
Zhao, Guangkuan,Samanta, Shyam S.,Michieletto, Jessica,Roche, Stéphane P.
, p. 5822 - 5827 (2020)
A versatile synthetic protocol of aza-Friedel-Crafts alkylation has been developed for the synthesis of quaternary α-amino esters. This operationally simple alkylation proceeds under ambient conditions with high efficiency, regioselectivity, and an exceptionally broad scope of arene nucleophiles. A key feature of this alkylation is the role associated with the silver(I) salt counteranions liberated during the reaction. Taking advantage of a phase-transfer counteranion/Br?nsted acid pair mechanism, we also report a catalytic enantioselective example of the reaction.
Mechanistic Studies and Expansion of the Substrate Scope of Direct Enantioselective Alkynylation of α-Ketiminoesters Catalyzed by Adaptable (Phebox)Rhodium(III) Complexes
Morisaki, Kazuhiro,Sawa, Masanao,Yonesaki, Ryohei,Morimoto, Hiroyuki,Mashima, Kazushi,Ohshima, Takashi
supporting information, p. 6194 - 6203 (2016/06/09)
Mechanistic studies and expansion of the substrate scope of direct enantioselective alkynylation of α-ketiminoesters catalyzed by adaptable (phebox)rhodium(III) complexes are described. The mechanistic studies revealed that less acidic alkyne rather than more acidic acetic acid acted as a proton source in the catalytic cycle, and the generation of more active (acetato-κ2O,O′)(alkynyl)(phebox)rhodium(III) complexes from the starting (diacetato)rhodium(III) complexes limited the overall reactivity of the reaction. These findings, as well as facile exchange of the alkynyl ligand on the (alkynyl)rhodium(III) complexes led us to use (acetato-κ2O,O′)(trimethylsilylethynyl)(phebox)rhodium(III) complexes as a general precatalyst for various (alkynyl)rhodium(III) complexes. Use of the (trimethylsilylethynyl)rhodium(III) complexes as precatalysts enhanced the catalytic performance of the reactions with an α-ketiminoester derived from ethyl trifluoropyruvate at a catalyst loading as low as 0.5 mol % and expanded the substrate scope to unprecedented α-ketiminophosphonate and cyclic N-sulfonyl α-ketiminoesters.
Incorporation of the unusual Cα-fluoroalkylamino acids into cyclopeptides: Synthesis of arginine-glycine-aspartate (RGD) analogues and study of their conformational and biological behavior
Dal Pozzo, Alma,Ni, Minghong,Muzi, Laura,De Castiglione, Roberto,Mondelli, Rosanna,Mazzini, Stefania,Penco, Sergio,Pisano, Claudio,Castorina, Massimo,Giannini, Giuseppe
, p. 1808 - 1817 (2007/10/03)
A series of six arginine-glycine-aspartate (RGD) cyclopeptide analogues containing a Cα-di- or trifluoromethylamino acid (α-Dfm or α-TfmAaa) at different positions of the ring were synthesized. All peptides were obtained in two diastereomeric f
New Synthetic Pathways to 3,3,3-Trifluoroalanine, 2-Deutero-3,3,3-trifluoroalanine and their Derivatives
Burger, Klaus,Hoess, Eva,Gaa, Karl,Sewald, Norbert,Schierlinger, Christian
, p. 361 - 384 (2007/10/02)
New synthetic pathways to 3,3,3-trifluoroalanine, 2-deutero-3,3,3-trifluoroalanine, their esters, amides, and thioamides are described, starting from hexafluoroacetone, and trifluoropyruvates, respectively.
