○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
7
1. (+/-)
δ
-pentalactones
2. (+/-)
δ
-hexalactones
3. (+/-)
δ
-heptalactones
4. (+/-)
δ
-octalactones
5. (+/-)
δ
-nonalactones
6. (+/-)
δ
-decalactones
7. (+/-)
δ
-dodecalactones
Figure 10
All of the irone isomers are resolved
without overlapping of the enantiomeric
pairs on the Rt-
β
DEXcst column.
Figure 11
The Rt-
β
DEXcst column provides maximum
resolution of the
γ
-lactones and
δ
-lactones.
A.
γ
-lactones on the Rt-
β
DEXcst
column
B.
δ
-lactones
on the Rt-
β
DEXcst
column
min.
40
1. (-)-(2R,6R)-trans-
α
-irone
2. (+)-(2S,6S)-trans-
α
-irone
3. (+)-(2R,6R)-trans-
γ
-irone
4. (-)-(2S,6S)-trans-
γ
-irone
5. (+)-(2R,6S)-cis-
α
-irone
6. (+)-(2R,6S)-cis-
γ
-irone
7. (-)-(2S,6R)-cis-
γ
-irone
8. (-)-(2S,6R)-cis-
α
-irone
9. (+)-(2R)-
β
-irone
10. (-)-(2R)-
β
-irone
1
3
4
8
5
6
7
10
2
9
min. 100
120
1
3
4
5
2
140
1. (+/-)
γ
-heptalactones
2. (+/-)
γ
-octalactones
3. (+/-)
γ
-nonalactones
4. (+/-)
γ
-decalactones
5. (+/-)
γ
-dodecalactones
min. 100
120
1
3
4 5
2
140
6
7
30m, 0.32mm ID, 0.25µm
Rt-
β
DEXcst (cat.# 13102)
Oven temp.:
60°C (hold 1min.) to 200°C
@ 1°C/min.;
Carrier gas:
hydrogen;
40cm/sec. set @ 60°C;
Detector:
FID set @ 220°C
30m, 0.32mm ID, 0.25µm
Rt-
β
DEXcst (cat.# 13102)
Oven temp.:
40°C (hold 1min.) to
230°C@ 2°C/min. (hold 3min.);
Carrier gas:
hydrogen; 80cm/sec. set @ 40°C;
Detector:
FID set @ 220°C
Rt-
β
DEXcst
○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
This column is optimum for semi-
volatile chiral compounds because
lower boiling components show peak
broadening (discussed in the “Optimi-
zationofChiralSeparations”section).
All of the irone isomers (found in iris
flowers) are resolvedwithout overlap-
pingof theenantiomericpairs (
Figure
10
). This is also the best column for
resolution of the
γ
- and
δ
-lactones
(
Figures 11A and B
).
The Rt-
β
DEXcst column is good for
separating the enantiomers of some
barbiturates and TFA-derivatives of
amphetamines as well. This is dis-
cussed in further detail on pages 22
and 23.
Visit Restek on-line at
,
or call 800-356-1688,
ext. 4, for technical
assistance.
30m, 0.32mm ID, 0.25µm
Rt-
β
DEXcst (cat.# 13102)
Oven temp.:
60°C (hold 1min.) to 200°C
@ 1°C/min.;
Carrier gas:
hydrogen;
40cm/sec. set @ 60°C;
Detector:
FID set @ 220°C
