Chemical Dynamic Thermodynamic Resolution and S/R Interconversion of Unprotected Unnatural Tailor-made α-Amino Acids

J Org Chem. 2015 Oct 16;80(20):9817-30. doi: 10.1021/acs.joc.5b01292. Epub 2015 Sep 25.

Abstract

Described here is an advanced, general method for purely chemical dynamic thermodynamic resolution and S/R interconversion of unprotected tailor-made α-amino acids (α-AAs) through intermediate formation of the corresponding nickel(II)-chelated Schiff bases. The method features virtually complete stereochemical outcome, broad substrate generality (35 examples), and operationally convenient conditions allowing for large-scale preparation of the target α-AAs in enantiomerically pure form. Furthermore, the new type of nonracemizable axially chiral ligands can be quantitatively recycled and reused, rendering the whole process economically and synthetically attractive.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / chemistry*
  • Molecular Structure
  • Stereoisomerism
  • Thermodynamics*

Substances

  • Amino Acids