Reaktion #90290

Reaktionsgleichung

4-(3,4-bis(benzyloxy)-5-nitrophenyl)-2-(2-(trifluoromethyl)pyridin-3-yl)thiazole

boron tribromide

→

3-nitro-5-(2-(2-(trifluoromethyl)pyridin-3-yl)thiazol-4-yl)benzene-1,2-diol

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturbefore cooling again to −78° C
2. 2
   SonstigeThe mixture was quenched by careful addition of methanol
3. 3
   workup.STIRRINGAfter stirring at room temperature for thirty minutes
4. 4
   Sonstigethe volatiles were evaporated
5. 5
   workup.STIRRINGthe residue stirred with 2 N hydrochloric acid (5 mL) for thirty minutes
6. 6
   FiltrationThe resulting solid was filtered off
7. 7
   Waschenwashed with water (25 mL)

Vorschrift

A solution of 4-(3,4-bis(benzyloxy)-5-nitrophenyl)-2-(2-(trifluoromethyl)pyridin-3-yl)thiazole (0.146 g, 0.26 mmol), in dichloromethane (10 mL) was cooled to −78° C. and treated under argon, with boron tribromide (0.26 g, 1.03 mmol). The resulting deep purple suspension was then allowed to stir at room temperature for one hour before cooling again to −78° C. The mixture was quenched by careful addition of methanol. After stirring at room temperature for thirty minutes, the volatiles were evaporated and the residue stirred with 2 N hydrochloric acid (5 mL) for thirty minutes. The resulting solid was filtered off, washed with water (25 mL) and then cold isopropanol (5 mL) to give 3-nitro-5-(2-(2-(trifluoromethyl)pyridin-3-yl)thiazol-4-yl)benzene-1,2-diol as a yellow solid, 0.087 g (87%).

Quelle