Synthesis of Sterically Hindered N-Acylated Amino Acids from N-Carboxyanhydrides
摘要:
Sterically hindered N-acyl, gem-disubstituted amino acids are easily prepared via the addition of organometallic reagents to N-carboxyanhydrides (NCA). The process tolerates a wide variety of functional groups and allows the synthesis of amide products not readily accessible by traditional acylation chemistry. The existence of an isocyanate intermediate was established by in situ IR spectroscopy.
Palladium-Catalyzed Ortho-Alkoxylation of <i>N</i>-Benzoyl α-Amino Acid Derivatives at Room Temperature
作者:Shuangjie Li、Wei Zhu、Feng Gao、Chunpu Li、Jiang Wang、Hong Liu
DOI:10.1021/acs.joc.6b02257
日期:2017.1.6
An efficient palladium-catalyzed ortho-alkoxylation of N-benzoyl α-amino acid derivatives at roomtemperature has been explored. This novel transformation, using amino acids as directing groups, Pd(OAc)2 as catalyst, alcohols as the alkoxylation reagents, and PhI(OAc)2 as the oxidant, showed wide generality, good functional tolerance, and high monoselectivity and regioselectivity.