Reaktion #1969513

ord-4b4d1bc4648a41eb96504eacaffb582d

Reaktionsgleichung

C=C(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-isopulegol
[H][H]
hydrogen
CC(C)[C@@H]1CC[C@@H](C)C[C@H]1O
L-menthol

Reagenzien

Keine

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Sonstigewas operated at a temperature of 85° C.
  2. 2
    Sonstigeat 75° C
  3. 3
    SonstigeAll pipelines were provided with electrical trace
  4. 4
    Temperaturheating
  5. 5
    Sonstigethe crystallization of the enantiomerically pure L-menthol (m.p. 44° C.)

Vorschrift

By means of a centrifugal pump, a circulation was pumped through the main reactor at a rate of about 500 g/h at a feed of L-isopulegol of 24.5 g/h (total amount 588 g) with a purity of 99.9% by weight and 99.8% ee. The hydrogen pressure was kept constant at 40 bar. The main reactor was operated at a temperature of 85° C. and the postreactor at 75° C. All pipelines were provided with electrical trace heating to prevent the crystallization of the enantiomerically pure L-menthol (m.p. 44° C.). This gave L-menthol in an amount of 597 g, corresponding to a rate of 24.9 g/h. The L-menthol obtained in this way (99.8% ee) was analyzed by gas chromatography. The chemical purity of the L-menthol discharge is listed in Table 1.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08318985B2uspto-grants-2012_11