Reaction #1701

Reaction equation

diethyl 1-(6-chloro-1-oxoindan-2-yl)imidazole-2,4-dicarboxylate

ammonium acetate

acetic acid

→

ethyl 7-chloro-4,5-dihydro-4-oxo-10H-imidazo[1,2-a]indeno[1,2-e]pyrazine-2-carboxylate

Yield 61.7%

Solvents

acetonitrile

methanol

acetone

Conditions

Workup

1. 1
   WashAfter washing the precipitate with water
2. 2
   Otherwith methyl ethyl ketone, the solid obtained

Procedure

The procedure is as in Example 1 but starting from 5 g of diethyl 1-(6-chloro-1-oxoindan-2-yl)imidazole-2,4-dicarboxylate, 118 g of ammonium acetate and 190 ml of acetic acid. After washing the precipitate with water and then with methyl ethyl ketone, the solid obtained is first of all ground in acetonitrile and then in methanol and finally in acetone to obtain 2.7 g of ethyl 7-chloro-4,5-dihydro-4-oxo-10H-imidazo[1,2-a]indeno[1,2-e]pyrazine-2-carboxylate in the form of a brown solid melting above 260° C. (analysis % calculated C: 58.28, H: 3.67, Cl: 10.75, N: 12.74; % found C: 58.6, H: 3.4, Cl: 10.4, N: 13.1).

Source