Reaktion #1705

Reaktionsgleichung

sodium hydroxide

ethyl 4,5-dihydro-4-oxo-10H-imidazo[1,2-a]indeno[1,2-e]pyrazine-2-carboxylate

→

4,5-dihydro-4,10-dioxoimidazo[1,2-a]indeno[1,2-e]pyrazine-2-carboxylic acid

Lösungsmittel

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeis bubbled for 15 hours
2. 2
   workup.ADDITIONAfter addition of 10 ml of distilled water the mixture
3. 3
   FiltrationThe precipitate form is filtered off
4. 4
   Waschenwashed with water
5. 5
   Sonstigedried

Vorschrift

5 ml of 1N sodium hydroxide are added to a suspension of 0.2 g of ethyl 4,5-dihydro-4-oxo-10H-imidazo[1,2-a]indeno[1,2-e]pyrazine-2-carboxylate in 15 ml of dioxane, and the reaction mixture is stirred vigorously while compressed air is bubbled for 15 hours. After addition of 10 ml of distilled water the mixture is acidified with concentrated hydrochloric acid. The precipitate form is filtered off, washed with water and dried to produce 0.13 g of 4,5-dihydro-4,10-dioxoimidazo[1,2-a]indeno[1,2-e]pyrazine-2-carboxylic acid in the form of a brown powder whose melting point is higher than 260° C. (1H spectrum in DMSO, T=300K, δ in ppm (200 MHz): between 7.35 and 7.65 (3H, m, CH arom. ), 7.75 (1H, d, J=7 Hz, CH arom.), 8.38 (1H, s, CH arom.), 12.5 (1H, s, NH)).

Quelle