Hydrochloric Acid → HCID 18975444, compound

Participants

Reaction Steps

To a solution of 0.22 g of ethyl 4-ethoxycarbonyloxy-10H-imidazo[1,2-a]indeno[1,2-e]-pyrazine-10,10-dicarboxylate in 20 ml of tetrahydrofuran are added 5.5 ml of 1N hydrochloric acid at a temperature in the region of 20° C. After reacting overnight at the same temperature, the tetrahydrofuran is evaporated off under reduced pressure (15 mmHg; 2 kPa) and the aqueous solution thus obtained is diluted with 5 ml of distilled water. The addition of 10 ml of ethyl acetate causes formation of a cream-coloured precipitate which is filtered off, washed and dried to give 0.15 g of ethyl 5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazin-4-one-10-carboxylate hydrochloride in the form of a cream-coloured solid (NMR spectrum: [200 MHz; (CD3)2SO-d6 ; δ in ppm]: 1.23 (t, J=7.5 Hz, 3H: --CH3 ethyl); from 4.00 to 4.40 (mt, 2H: --OCH2 -ethyl); 5.41 (s, 1H: --CH-- 10); 7.43 and 7.51 (2 broad t, J=8 Hz, 1H each: --H 7 and --H 8); 7.75 and 7.97 (2 broad d, J=8 Hz, 1H each: --H 6 and --H 9); 7.82 and 8.14 (2s, 1H each: --H of the imidazole); 12.95 (mult., 1H: --CONH--)).

Provenance & Evidence