1,2-Diphenylethane-1,2-diamine: an effective NMR chiral solvating agent for chiral carboxylic acids
- 1 January 1994
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of the Chemical Society, Perkin Transactions 2
- No. 1,p. 57-64
- https://doi.org/10.1039/p29940000057
Abstract
(1R,2R)-1,2-diphenylethane-1,2-diamine, 1, acts as an effective chiral solvating agent (CSA) in the 1H NMR analysis of the enantiomeric purity of chiral carboxylic acids. In the 2:1 salt complexes with a range of acids including α-arylpropanoic, α-halo carboxylic acid and primary carboxylic acids, RCH2CO2H, the diastereotopic resonances in 1H NMR were typically more than 0.05 ppm shift non-equivalent. The effect of temperature, stoichiometry, acid enantiomeric purity, concentration and solvent on the observed shift non-equivalence was studied. The structure of the CSA was varied systematically and the observed non-equivalence with 1, may be attributed to the anisotropy of the second aryl ring which is proximate to the substituents α to the carboxylic acid group.Keywords
This publication has 0 references indexed in Scilit: