title: Visible-light photoredox synthesis of unnatural chiral α-amino acids.
abstract: Unnatural chiral α-amino acids are widely used in fields of organic chemistry, biochemistry and medicinal chemistry, and their synthesis has attracted extensive attention. Although the asymmetric synthesis provides some efficient protocols, noble and elaborate catalysts, ligands and additives are usually required which leads to high cost. Distinctly, it is attractive to make unnatural chiral α-amino acids from readily available natural α-amino acids through keeping of the existing chiral α-carbon. However, it is a great challenge to construct them under mild conditions. In this paper, 83 unnatural chiral α-amino acids were prepared at room temperature under visible-light assistance. The protocol uses two readily available genetically coded proteinogenic amino acids, L-aspartic acid and glutamic acid derivatives as the chiral sources and radical precursors, olefins, alkynyl and alkenyl sulfones, and 2-isocyanobiphenyl as the radical acceptors, and various unnatural chiral α-amino acids were prepared in good to excellent yields. The simple protocol, mild conditions, fast reactions, and high efficiency make the method an important strategy for synthesis of diverse unnatural chiral α-amino acids.
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Min
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Yunhe
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Haijun
authors.initials: H
authors.lastname: Yang
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
authors.forename: Hua
authors.initials: H
authors.lastname: Fu
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis*; D002625:Chemistry, Organic / Q000379:methods*; D008027:Light; D010084:Oxidation-Reduction; D013696:Temperature
chemical_list: D000596:Amino Acids