ISSN:
1438-2199
Keywords:
Amino acids
;
α-Amino acid esters
;
Absolute configuration
;
CD
;
Eu(fod)3
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary The NMR shift reagent, Europium(III)-tris-(1,1,1,2,2,3,3)-heptafluoro-7,7-dimethyl-4-6-octanedione [Eu(fod)3], complexes efficiently withα-amino acid esters in chloroform. These complexes exhibit characteristic circular dichroism (CD) spectral patterns in the 350-250 nm region. A fast and simple procedure (also in microscale) has been worked out which utilizes the signs of these CD bands for the determination of the absolute configuration at theα-carbon atomin situ. In the L-series, a positive CD band is observed at around 310 nm and a negative one in the 290-280 nm region. The CD spectra of the Eu complexes of the D-isomers are mirror images of those of the L-configurations. An empirical rule is proposed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00806784
Permalink