Reaktion #1543043

Reaktionsgleichung

2-chloro-4-methylsulfonylbenzoyl chloride

aluminum chloride

1,1,2,2-tetrachloroethane

hydrochloric acid

→

2,2', 4'-Trichloro-6'-hydroxy-4-methylsulfonylbenzophenone

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture is subsequently refluxed for 7 hours
2. 2
   SonstigeThe organic phase is removed
3. 3
   Extraktionthe aqueous phase is extracted twice
4. 4
   WaschenThe combined organic phases are washed until neutral and
5. 5
   Extraktionsubsequently extracted three times
6. 6
   FiltrationThe precipitate is filtered off
7. 7
   Waschenwashed with water until neutral and
8. 8
   Sonstigedried

Vorschrift

3.00 g of 2-chloro-4-methylsulfonylbenzoyl chloride are added in portions at room temperature to a mixture of 1.97 g of 3,5-dichlorophenone and 3.23 g of aluminum chloride in 50 ml of 1,1,2,2-tetrachloroethane, and the mixture is subsequently refluxed for 7 hours. When cold, the reaction mixture is poured onto 100 g of ice and 20 ml of concentrated hydrochloric acid. The organic phase is removed, and the aqueous phase is extracted twice using 50 ml of dichloromethane. The combined organic phases are washed until neutral and subsequently extracted three times using in each case 25 ml of 2N sodium hydroxide solution. The combined alkaline extracts are brought to a pH of 2 using concentrated hydrochloric acid. The precipitate is filtered off, washed with water until neutral and dried. This gives 3.194 g (70% of theory) of 2,2', 4'-trichloro-6'-hydroxy-4-methylsulfonylbenzophenone in the form of colorless crystals with a melting point of 123°-126° C.

Quelle