Formaldehyde → 3-(4-Methoxyphenyl)-5,6-dihydroimidazo[1,5-c]quinazoline

Reaction equation

[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([C:9]2[NH:10][CH:11]=[C:12]([C:14]3[CH:19]=[CH:18][CH:17]=[CH:16][C:15]=3[NH2:20])[N:13]=2)=[CH:5][CH:4]=1.[CH2:21]=O>C(O)(=O)C.C(OCC)(=O)C>[CH3:1][O:2][C:3]1[CH:4]=[CH:5][C:6]([C:9]2[N:13]3[CH2:21][NH:20][C:15]4[CH:16]=[CH:17][CH:18]=[CH:19][C:14]=4[C:12]3=[CH:11][N:10]=2)=[CH:7][CH:8]=1

Participants

Procedure

2-(4-Methoxyphenyl)-4-(2-aminophenyl)imidazole (5 g) is dissolved in acetic acid (20 ml) and formaldehyde (37% in water, 1.53 ml) is added. The reaction is stirred for 2 min., diluted with ethyl acetate (100 ml), and extracted with 5%HCl (250 ml). The aqueous layer is basified with K2CO3, then extracted with ethyl acetate. The organic layer is evaporated under reduced pressure and the residue is recrystallized from dichloromethane to afford 3-(4-methoxyphenyl)-5,6-dihydroimidazo[1,5-c]quinazoline (3 g) as a light brown solid. m.p. 190-191° C.