Reaktion #78772

Reaktionsgleichung

3-trifluoromethoxybenzaldehyde

diethyl (2-oxopropyl)phosphonate

NaOH

→

4-[3-(trifluoromethoxy)phenyl]-3-buten-2-one

Ausbeute 54.0%

Lösungsmittel

methylene chloride

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigequenched with water
2. 2
   Extraktionextracted with hexane
3. 3
   TrocknenThe hexane layer was dried over MgSO4
4. 4
   SonstigeThe crude product was purified by flash column chromatography on silica gel eluting with 1:10 ethyl acetate in hexane

Vorschrift

EX-626A) Tetrabutylammonium iodide (0.4 g, 0.05 mol) was added to a well-stirred biphasic mixture of 12 mL of 50% NaOH and 20 mL of methylene chloride under a nitrogen atmosphere. A solution of 3-trifluoromethoxybenzaldehyde (4.0 g, 0.021 mol) and diethyl (2-oxopropyl)phosphonate (4.08 g, 0.021 mol) in 4.0 mL of methylene chloride was added dropwise to the stirred solution. The resulting mixture was stirred at room temperature for 15 min, then quenched with water and extracted with hexane. The hexane layer was dried over MgSO4. The crude product was purified by flash column chromatography on silica gel eluting with 1:10 ethyl acetate in hexane to give 2.6 g (54%) of the desired 4-[3-(trifluoromethoxy)phenyl]-3-buten-2-one product as a yellow oil. 1H NMR (CDCl3) δ 7.43 (m, 4H), 7.20 (d, 1H), 6.65 (d, 2H), 2.29 (s, 3H). 19F NMR (CDCl3) δ −62.05 (s, 3F).

Quelle