Reaktion #550576

Reaktionsgleichung

Pyridinium hydrobromide

ethyl 2-methoxyimino-3,3-dimethoxybutyrate

water

→

ethyl-2-methoxyimino-3,3-dimethoxy-4-bromobutyrate

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated
2. 2
   Temperaturunder reflux for an hour
3. 3
   Extraktionextracted with diethyl ether (10 ml×2)
4. 4
   WaschenThe extract was washed with 5% aqueous sodium thiosulfate solution (5 ml×5)
5. 5
   TrocknenThe solution was dried over magnesium sulfate
6. 6
   Sonstigeevaporated under reduced pressure

Vorschrift

Pyridinium hydrobromide perbromide (1.82 g) was added to a solution of ethyl 2-methoxyimino-3,3-dimethoxybutyrate (syn isomer, 1.0 g) in dry tetrahydrofuran (10 ml) and heated under reflux for an hour. The resultant solution was poured into water (30 ml) and extracted with diethyl ether (10 ml×2). The extract was washed with 5% aqueous sodium thiosulfate solution (5 ml×5) and a saturated aqueous solution of sodium chloride (10 ml×1) successively. The solution was dried over magnesium sulfate and evaporated under reduced pressure to give ethyl-2-methoxyimino-3,3-dimethoxy-4-bromobutyrate (syn isomer, 2.02 g).

Quelle