Page 236 - Chiral Separation Techniques

214 8 Nonchromatographic Solid-Phase Purification of Enantiomers

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Table 8-2. Singe column (3.9 g ChiraLig ) loading curve of 24 mMD-methyl ester valine versus 25 mM
–1
L-methyl ester valine in 3 M LiClO and 0.1 M HClO at a flowrate of 0.4 ml min .
4 4
Concentration (mM) a
Sample description
D-Valine-ester L-Valine ester
Feed 25 25
0–5 ml feed effluent b b
5–9 ml feed effluent b b
9–14.25 ml feed effluent b 0.9
14.25–19.5 ml feed effluent b 2.8
19.5–24.6 ml feed effluent b 6.4
24.6–33.5 ml feed effluent 2 15
33.5–53.5 ml feed effluent 10 30.5
53.5–61 ml feed effluent 17.5 32.8
61–68.5 ml feed effluent 20 34.5

a Analyzed by HPLC.
b Below detection limit of 0.2 mM.

Table 8-3. First cycle, three-column (each 3.9 g ChiraLig TM ) polishing curve for loading 25 mMD-
methyl ester valine versus 25 mML-methyl ester valine in 3 M LiClO and 0.1 M HClO at a flowrate of
4
4
–1
0.4 ml min .
Concentration (mM) a
Sample description
D-Valine-ester L-Valine ester
Feed 25 25
0–70 ml feed effluent b 2.9
70–76 ml feed effluent b 3.0
76–81 ml feed effluent b 9.6
81–85 ml feed effluent b 11.7
85–89 ml feed effluent b 14.1

a Analyzed by HPLC.
b Below detection limit of 0.2 mM.

Table 8-4. Second cycle, two-column (each 3.9 g ChiraLig™) polishing curve for loading 25 mM
D-methyl ester valine versus 25 mML-methyl ester valine in 3 M LiClO and 0.1 M HClO at a flowrate
4
4
–1
of 0.4 ml min .
Concentration (mM) a
Sample description
D-Valine-ester L-Valine ester
Feed 25 25
0–50 ml feed effluent 2.7 28.3
50–55 ml feed effluent 11.8 36.4
55–60 ml feed effluent 13.5 34.1
Σ mmol combined effluent 0.26 1.77
a Analyzed by HPLC.