Reaktion #11875

Reaktionsgleichung

2-dimethoxy-phenyl propionic acid methyl ester

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

sulfuric acid

→

6-(2-methoxy-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
   TemperaturAfter cooling
2. 2
   Sonstigequenched with 2 N aqueous sodium hydroxide solution
3. 3
   SonstigeThe organic layer was separated
4. 4
   Waschensuccessively washed with water (30 mL) and brine (30 mL)
5. 5
   Trocknendried over anhydrous sodium sulfate
6. 6
   Filtrationfiltered
7. 7
   Einengenconcentrated in vacuo
8. 8
   Sonstigeto give the crude product
9. 9
   SonstigeThe crude product was crystallized from ethyl acetate-hexanes

Vorschrift

To a solution of 3-(2,4-diphenylamino-pyrimidin-5-yl)-2-(2-dimethoxy-phenyl propionic acid methyl ester (181.8 mg, 0.40 mmol) (from Example 7b supra) was added 5% concentrated sulfuric acid in glacial acetic acid (3 mL) in one portion. The reaction mixture was heated at 110° C. for 3 hours. After cooling, the reaction mixture was 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. The crude product was crystallized from ethyl acetate-hexanes to give 6-(2-methoxy-phenyl)-8-phenyl-2-phenylamino-5,8-dihydro-6H-pyrido[2,3-d]pyrimidin-7-one as an off-white solid. (Yield 119.4 mg, 67.2%).

Quelle