Synlett 2016; 27(04): 551-554
DOI: 10.1055/s-0035-1560547
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© Georg Thieme Verlag Stuttgart · New York

31P NMR Based Method for Determining Enantiopurity of Chiral Phosphoric Acids and Its Application to the BINOL- and H8-BINOL-Based Chiral Phosphoric Acid Thermal Racemization Studies

Jia-Hui Tay
Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA   Email: nagorny@umich.edu
,
Pavel Nagorny*
Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA   Email: nagorny@umich.edu
› Author Affiliations
Further Information

Publication History

Received: 01 September 2015

Accepted after revision: 02 November 2015

Publication Date:
30 November 2015 (online)

We dedicate this Letter to Professor James D. White on the occasion of his 80th birthday

Abstract

A simple and reliable protocol for determining the enantiopurity of 3,3′-substituted BINOL- and H8-BINOL-based chiral phosphoric acids (CPA) using 31P NMR spectroscopy in the presence of chiral amines as the discriminating agents is described. The generality of this method is demonstrated using nine common BINOL- and H8-BINOL-based chiral acids. This technique was utilized for monitoring the extent of racemization of 3,5-(F3C)2C6H3-substituted BINOL- and H8-BINOL-based CPA at 200, 220, and 250 °C.

Supporting Information

 
  • References and Notes


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