Réaction #155362

Équation de réaction

dibenzothiophene

aluminum chloride

phthalic anhydride

hydrochloric acid

→

2-(o-carboxybenzoyl)dibenzothiophene

Rendement 107.2%

Solvants

dichloromethane

dichloromethane

dichloromethane

water

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONis added
2. 2
   Températureunder cooling with ice
3. 3
   workup.ADDITIONAfter addition
4. 4
   workup.STIRRINGto stir at 23° C. for 4 hours
5. 5
   ExtractionThe product extracted with dichloromethane (2 200 cm3)
6. 6
   Extractionthe organic extracted with aqueous sodium hydroxide (5%, 500 cm3)
7. 7
   Autrethe oily precipitate is isolated
8. 8
   Autreby decanting away the acidic solution
9. 9
   workup.ADDITIONWater (200 cm3) is added
10. 10
    Filtrationthe solid collected by filtration
11. 11
    Lavagewashed with water (500 cm3)
12. 12
    Autredried under vacuum

Mode opératoire

To a mixture of aluminum chloride (40.0 g, 300 mmol) in anhydrous dichloromethane (1000 cm3) is added a suspension of phthalic anhydride (14.8 g, 100 mmol) in anhydrous dichloromethane (200 cm3). The suspension is stirred for 30 minutes, cooled to 5° C. and then a solution of dibenzothiophene (20.0 g, 110 mmol) in anhydrous dichloromethane (200 cm3) added drop wise under cooling with ice. After addition, the mixture is allowed to stir at 23° C. for 4 hours. The reaction mixture poured into a solution of water (1000 cm3) and concentrated hydrochloric acid (400 cm3). The product extracted with dichloromethane (2 200 cm3) and the organic extracted with aqueous sodium hydroxide (5%, 500 cm3). The basic layer acidified and the oily precipitate is isolated by decanting away the acidic solution. Water (200 cm3) is added, which solidified the oil and the solid collected by filtration, washed with water (500 cm3) and dried under vacuum to give 2-(o-carboxybenzoyl)dibenzothiophene as a pale yellow solid (35.64 g, 99%). 1H NMR (300 MHz, CDCl3) 8.47-8.52 (m, 1H), 7.99-8.15 (m, 2H), 7.60-7.86 (m, 4H), 7.35-7.57 (m, 4H).

Source