Reaction #2510563

ord-3b2399e3d69546fd8f55e274afe62d9e

Reaction equation

C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
CC(C)=CCCC(C)CCO
citronellol
C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
CC(C)=CCCC(C)CC=O
citronellal
C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
isopulegol
[H][H]
hydrogen
→
CC(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-menthol

Reactants

C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
CC(C)=CCCC(C)CCO
citronellol
C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
CC(C)=CCCC(C)CC=O
citronellal
C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
isopulegol
[H][H]
hydrogen

Reagents

None

Conditions

Temperature
80°CELSIUS
Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    Otherto 70° C

Procedure

Example 1 was repeated using L-isopulegol with a purity of 97.1% and 84% ee, which was introduced at a rate of 24.5 g/h (total amount 466 g) into the reactor at a hydrogen pressure of 40 bar. The main reactor (MR) was heated to 80° C., the postreactor to 70° C. The L-isopulegol used had the following composition: L-isopulegol: 97.1 GC % by weight, citronellol: 0.05 GC % by weight, citronellal: 0.40 GC % by weight, isopulegol isomer: 0.45 GC % by weight, secondary components: 0.34 GC % by weight. L-menthol (84% ee) was obtained in an amount of 468 g, corresponding to a rate of 24.6 g/h. The chemical purity of the L-menthol output is shown in Table 3.

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US07960593B2uspto-grants-2011_06