Ammonium Chloride → 1,5-Dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one
Reaktionsgleichung
Br[CH:2]1[C:8](=[O:9])[CH:7](Br)[C:6]2([CH3:12])[O:11][C:3]1([CH3:13])[CH:4]=[CH:5]2.[Cl-].[NH4+]>[Zn].[Cu]>[CH3:12][C:6]12[O:11][C:3]([CH3:13])([CH:4]=[CH:5]1)[CH2:2][C:8](=[O:9])[CH2:7]2Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
To a stirred slurry of 2,4-dibromo-1,5-dimethyl-8-oxabicyclo[3.2.1]oct-6-en-3-one (18.0 g) in a saturated methanolic solution of ammonium chloride (514 ml) was added portionwise zinc/copper couple (51 g) over 30 minutes at 23° C. The suspension was stirred for an additional 2 hours and filtered. The filtrate was diluted with a saturated Na2H2 -ethylenediaminetetraacetic acid solution (400 ml). Extraction with methylene chloride (5×100 ml) and drying (MgSO4) produced, upon evaporative removal of solvent, the desired ketone (9.0 g). Bulb-to-bulb distillation <80° C. and 0.5 mm afforded the desired product (7.3 g) as colorless crystals, m.p. 62°-63° C.