Reaction #2194

Reaction equation

Difluoromethyl chloride

4-chloro-4'-mercaptomethylbenzophenone

potassium hydroxide

dioxane

4-chloro-4'-mercaptomethylbenzophenone

→

desired product

Yield 36.0%

4-Chloro-4'-difluoromethylthiomethyl-benzophenone

Yield 36.0%

Solvents

water

Conditions

Workup

1. 1
   Filtrationsubjected to filtration
2. 2
   DryingThe organic layer as the filtrate was dried over anhydrous magnesium sulfate
3. 3
   workup.ADDITIONadd
4. 4
   Concentrationconcentrated
5. 5
   OtherThe residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=5:1)

Procedure

4-chloro-4'-mercaptomethylbenzophenone (14.7 g) and potassium hydroxide (15 g) was added to a solvent comprising dioxane (100 ml) and water (100 ml). Difluoromethyl chloride was blown into this solution at 60° C. until the starting material 4-chloro-4'-mercaptomethylbenzophenone disappeared. The reaction product was cooled to room temperature and then subjected to filtration. The organic layer as the filtrate was dried over anhydrous magnesium sulfate add concentrated. The residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=5:1) to obtain the desired product (6.4 g, melting point: 34° to 35° C., yield: 36%).

Source