1-(diphenylmethyl)-1H-indole-2,3-dione → 1-(diphenylmethyl)-3-hydroxy-3-(7-hydroxyquinoxalin-6-yl)-1,3-dihydro-2H-indol-2-one

Temperatur

0 °C

To a stirred solution of quinoxalin-6-ol (King et al.; J. of the Chem. Society 1949:3012.) (11.2 g, 76.66 mmol) in tetrahydrofuran (800 mL) was added isopropylmagnesium chloride (38.3 mL, 2.0 M THF solution, 76.60 mmol) at −40° C. to −30° C. The mixture was allowed to stir at 0° C. for 2 h, followed by the addition of 1-(diphenylmethyl)-1H-indole-2,3-dione (20.00 g, 63.84 mmol) in tetrahydrofuran (400 mL). The mixture was stirred at ambient temperature for 20 h, and quenched with saturated ammonium chloride solution and extracted with ethyl acetate (3×1000 mL). The organic layer was washed with water and brine, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo, and the residue was purified by column chromatography (dichloromethane/methanol, 100/1) to give 1-(diphenylmethyl)-3-hydroxy-3-(7-hydroxyquinoxalin-6-yl)-1,3-dihydro-2H-indol-2-one (10.0 g, 34%): 1H NMR (300 MHz, CDCl3) δ 10.21 (s, 1H), 8.47 (s, 1H), 7.97-7.92 (m, 2H), 7.60-7.58 (m, 2H), 7.54-7.49 (m, 4H), 7.46-7.35 (m, 6H), 7.14 (s, 1H), 7.05-7.00 (m, 1H), 6.89-6.87 (m, 1H), 6.56-6.52 (m, 1H).

1. stirringThe mixture was stirred at ambient temperature for 20 h
2. customquenched with saturated ammonium chloride solution
3. extractionextracted with ethyl acetate (3×1000 mL)
4. washThe organic layer was washed with water and brine
5. dry with materialdried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationThe filtrate was concentrated in vacuo
8. customthe residue was purified by column chromatography (dichloromethane/methanol, 100/1)

ORD-Eintrag

ord-45470b6c6e434a148fff92e488917e13

Quelldatensatz

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08916580B2