Ethyl vinyl ether → 1-Bromo-5-vinyloxy-cyclopentene
Reaktionsgleichung
[Br:1][C:2]1[CH:3]([OH:7])[CH2:4][CH2:5][CH:6]=1.[CH:8](OCC)=[CH2:9]>[Hg](OC(C)=O)OC(C)=O>[Br:1][C:2]1[CH:3]([O:7][CH:8]=[CH2:9])[CH2:4][CH2:5][CH:6]=1Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
A solution of 2-bromo-cyclopent-2-enol (Intermediate D3) (21.7 g, 133.1 mmol) in ethyl vinyl ether (300 mL) was treated with Hg(OAc)2 (31.8 g, 99 mmol) at rt for 60 h. The mixture was quenched with 5% NaOH (150 mL) and filtered through celite. The residue was concentrated to yield 1-bromo-5-vinyloxy-cyclopentene as a pale yellow oil, 14.2 g (46%). 1-Bromo-5-vinyloxy-cyclopentene (14.1 g, 74.4 mmol) in toluene was heated in a re-sealable tube at 130° C. for 24 h. (2-Bromo-cyclopent-2-enyl)-acetaldehyde (Intermediate ONE 1) was isolated after flash chromatography on silica gel with hexanes to 5% ethyl acetate:hexanes, 10.4 g (74%).