Hydrochloric Acid → 5,6-dihydro-2-(2-phenylethyl)-4H-imidazo[4,5,1-ij]quinoline

Reaction equation

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

Participants

Procedure

Thirty-five grams of 8-amino-1,2,3,4-tetrahydroquinoline was dissolved in methanol (700 mL) and, following the addition of 3-phenylpropionaldehyde (37.4 mL) and 1N HCl (7 mL) and subsequent stirring at room temperature for 1 hr, silica gel (75 g) was added to the reaction solution and the solvent was removed under reduced pressure. The residue was heated at 100° C. for 1 hr, purified by silica gel column chromatography (eluent: dichloromethane/ethyl acetate) and recrystallized with ethyl acetate to yield the titled compound as pale yellow crystals (19.3 g).