Diastereomer method for determining ee by (1)H NMR and/or MS spectrometry with complete removal of the kinetic resolution effect.
[structure: see text] Using chiral auxiliaries, 2-methoxy-2-(1-naphthyl)propionic acid (MalphaNP acid) (S)-(+)-1 and its deuterium-labeled enantiomer (R)-(-)-1-d(n)() (n = 3 or 6), we have developed a new diastereomer method for determining enantiomeric excess (% ee) of chiral alcohols by (1)H NMR and/or MS spectrometry, where the kinetic resolution effect is completely excluded. The data of % ee determined by this method agree well with those calculated by weight, the average error being ca. +/-1.08% ee.
Taji
Hiromi
H
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan.
Watanabe
Masataka
M
Harada
Nobuyuki
N
Naoki
Hideo
H
Ueda
Yoshihisa
Y