Two-component chiral phase transfer catalysts: enantioselective esterification of an N-acylated amino acid
1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA. sesnyder@uiuc.edu
Abstract:
[see reaction]. The first example of a two-component chiral phase transfer catalyst is described which, operating in a biphasic solvent system, preferentially esterifies one enantiomer of a racemic N-acylated amino acid. The two-component catalyst is comprised of an achiral quaternary ammonium ion and a proline-derived chiral selector initially developed for the liquid chromatographic separation of enantiomers.
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