Free Radical-Mediated Aryl Amination and Its Use in a Convergent [3 + 2] Strategy for Enantioselective Indoline α-Amino Acid Synthesis
作者:Rajesh Viswanathan、Erode N. Prabhakaran、Michael A. Plotkin、Jeffrey N. Johnston
DOI:10.1021/ja0284308
日期:2003.1.1
reduction by stannane, offering an advantage over the use of diazo and azide functional groups as nitrogen sources for carbon radicals. The free radical-mediated aryl amination was sequenced with the O'Donnell phase transfer-catalyzed enantioselective alkylation strategy of glycinyl imine to provide either enantiomer of indoline alpha-amino acids with high ee. These new constrained phenyl alanine derivatives
The present invention provides methodology for carbon-nitrogen bond formation via vinyl or aryl amination. In the process of the invention, an sp
2
hybridized radical is reacted with an azomethine moiety to form pyrrolidine and indole compounds. The methodology provides a facile process for the synthesis of compounds having the pyrrolidine or indole subunit and is especially advantageous for compounds having acid or base labile functional groups andor is comprised of chiral centers susceptible to acidbase epimerization.