Reaktion #415932

Reaktionsgleichung

cyclopentene

benzene

2-carbomethoxy-3-oxo-5-acetoxycyclopentaneacetic acid

barium sulfate

→

2-Carbomethoxy-3-Oxo-5-Acetoxycyclopentaneacetic Acid Methyl Ester

Lösungsmittel

CHCl3

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeis hydrogenated at room temperature
2. 2
   SonstigeWhen the theoretical amount of hydrogen is absorbed
3. 3
   Filtrationcatalyst is filtered off
4. 4
   Sonstigethe solution is evaporated to dryness under vacuum
5. 5
   Sonstigeyielding 9 g

Vorschrift

The cyclopentene acid, V, (9.5 g.) is dissolved in 180 ml. of benzene and the solution is hydrogenated at room temperature and atmospheric pressure in the presence of 0.5 g. of palladiated barium sulfate. When the theoretical amount of hydrogen is absorbed, catalyst is filtered off and the solution is evaporated to dryness under vacuum, yielding 9 g. (95%) of the methy ester of 2-carbomethoxy-3-oxo-5-acetoxycyclopentaneacetic acid with the required stereochemical configuration. The compound is a rather unstable solid, melting at 54° C; [α]d25 :- 17.8 (C=1.017% in CHCl3).

Quelle