Reaktion #11879

Reaktionsgleichung

3-(2,4-diphenylamino-pyrimidin-5-yl)-2-(3,5-bis-trifluoromethyl-phenyl)-propionic acid methyl ester

sulfuric acid

→

6-(3,5-bis-trifluoromethyl-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one

Lösungsmittel

ethyl acetate

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigequenched with 2 N aqueous sodium hydroxide solution
2. 2
   SonstigeThe organic layer was separated
3. 3
   Waschensuccessively washed with water (30 mL) and brine (30 mL)
4. 4
   Trocknendried over anhydrous sodium sulfate
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated in vacuo
7. 7
   Sonstigeto give the crude product which
8. 8
   Sonstigewas crystallized from ethyl acetate-hexanes

Vorschrift

To a solution of 3-(2,4-diphenylamino-pyrimidin-5-yl)-2-(3,5-bis-trifluoromethyl-phenyl)-propionic acid methyl ester (0.20 g, 0.36 mmol) (from Example 8c supra) was added 5% concentrated sulfuric acid in glacial acetic acid (3 mL) in one portion. The reaction mixture was heated at 120° C. for 3 hours. The reaction mixture was then diluted with ethyl acetate (100 mL) and quenched with 2 N aqueous sodium hydroxide solution. The organic layer was separated and successively washed with water (30 mL) and brine (30 mL), dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give the crude product which was crystallized from ethyl acetate-hexanes to give 6-(3,5-bis-trifluoromethyl-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one as an off-white solid. (Yield 130.3 mg, 70.5%).

Quelle