Réaction #2075726

Équation de réaction

DMF

1-Bromo-4-chloro-2-fluoro-3-methoxybenzene

n-Butyllithium

→

title compound

Rendement 61.0%

4-Chloro-2-fluoro-3-methoxybenzaldehyde

Rendement 61.0%

Solvants

diethyl ether

Conditions de réaction

Traitement

1. 1
   Autre7,300,907 for preparation)
2. 2
   Autrethe temperature below −70° C.
3. 3
   workup.ADDITIONduring the addition
4. 4
   Autrethe temperature below −60° C
5. 5
   Températureto warm to ambient temperature
6. 6
   Autrequenched with water
7. 7
   AutreThe organic phase was dried
8. 8
   Concentrationconcentrated
9. 9
   AutreThe product was purified by flash chromatography on silica gel (hexane/ethyl acetate gradient)

Mode opératoire

1-Bromo-4-chloro-2-fluoro-3-methoxybenzene (23.7 g, 99 mmol, see U.S. Pat. No. 7,300,907 for preparation) was dissolved in dry diethyl ether and cooled to −78° C. 2.5M n-Butyllithium in hexanes (44 mL, 110 mmol) was added in portions, keeping the temperature below −70° C. during the addition. DMF (15.5 mL, 200 mmol) was then added in portions, keeping the temperature below −60° C. The reaction mixture was then allowed to warm to ambient temperature and quenched with water. The organic phase was dried and concentrated. The product was purified by flash chromatography on silica gel (hexane/ethyl acetate gradient) to yield the title compound in sufficient purity for subsequent reactions (11.4 g, 61% yield): 1H NMR (CDCl3) δ 10.32 (s, 1H), 7.55 (m, 1H), 7.3 (m, 1H), 4.05 (d, 3H).

Source