Reaction #2139937

Reaction equation

2,2,2-Trifluoro-1-(4-methoxyphenyl)-ethanone oxime

2-chloroethanesulfonyl chloride

triethylamine

p-toluenesulfinic acid sodium salt

→

product

2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone oxime 2-(p-toluene-sulfonyl)-ethanesulfonate

Solvents

THF

water

dimethylformamide

Conditions

Workup

1. 1
   Temperaturethe solution is cooled in an ice-bath
2. 2
   workup.STIRRINGthe reaction solution is stirred at room temperature for 0.5 h
3. 3
   Extractionthe crude product is extracted with ethyl acetate twice
4. 4
   Washwashed with water
5. 5
   Dryingdried over MgSO4
6. 6
   Concentrationconcentrated
7. 7
   OtherThe residue is purified by recrystallization from ethanol/toluene

Procedure

In 40 mL of THF are dissolved 4.38 g (20.0 mmol) of 2,2,2-Trifluoro-1-(4-methoxyphenyl)-ethanone oxime and the solution is cooled in an ice-bath. To the solution are added successively 2-chloroethanesulfonyl chloride (2.3 mL, 22.0 mmol) and triethylamine (6.4 mL, 46.0 mmol), and the reaction solution is stirred at 0° C. for 1 h. Then, p-toluenesulfinic acid sodium salt (3.56 g, 20.0 mmol) in dimethylformamide (DMF) (80 mL) is added and the reaction solution is stirred at room temperature for 0.5 h. After the reaction mixture is poured into water, the crude product is extracted with ethyl acetate twice, washed with water, dried over MgSO4 and concentrated. The residue is purified by recrystallization from ethanol/toluene to afford the product as white solid. The structure is confirmed by the 1H-NMR spectrum (CDCl3). δ [ppm]: 2.49 (s, 3H), 3.53 (t, 2H), 3.77 (t, 2H), 3.88 (s, 3H), 7.00 (d, 2H), 7.42 (d, 2H), 7.50 (d, 2H), 7.80 (d, 2H). mp. 157-158° C.

Source