Water → 2-Fluoro-4,5-dimethoxybenzene-1-sulfonyl chloride

Temperatur

85 °C

To a suspension of sulfur trioxide N,N-dimethylformamide complex (4.108 g, 27 mmol) in 1,2-dichloroethane was added 4-fluoroveratrole (3.49 g, 22 mmol) dropwise. The mixture was slowly heated to 85° C. in an oil bath. After 2.5 h, the solids had dissolved to afford a golden yellow solution. A trace of starting material was still present and heating was continued for a further 4.5 h. The oil bath was removed and thionyl chloride (1.95 ml, 27 mmol) added dropwise. The mixture was heated 4 h at 85° C. and allowed to cool to room temperature. The solution was poured into water and extracted with dichloromethane (3×50 ml), the combined organics washed with water, dried over magnesium sulfate and evaporated. Remaining traces of N,N-dimethylformamide were removed azeotropically with toluene to afford the product as an off-white solid that was used without further purification.

1. dissolutionthe solids had dissolved
2. customto afford a golden yellow solution
3. temperatureheating
4. waitwas continued for a further 4.5 h
5. customThe oil bath was removed
6. temperatureThe mixture was heated 4 h at 85° C.
7. temperatureto cool to room temperature
8. extractionextracted with dichloromethane (3×50 ml)
9. washthe combined organics washed with water
10. dry with materialdried over magnesium sulfate
11. customevaporated
12. customRemaining traces of N,N-dimethylformamide were removed azeotropically with toluene

ORD-Eintrag

ord-b855db2249d54a2ba556b403a7519397

Quelldatensatz

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07144890B2