Ethylenediamine → 3-(benzyloxy)-6-(4,5-dihydro-1H-imidazol-2-yl)-2-methoxyaniline
Reaction equation
[NH2:1][C:2]1[C:9]([O:10][CH3:11])=[C:8]([O:12][CH2:13][C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)[CH:7]=[CH:6][C:3]=1[C:4]#[N:5].[S].[CH2:21](N)[CH2:22][NH2:23]>>[CH2:13]([O:12][C:8]1[C:9]([O:10][CH3:11])=[C:2]([C:3]([C:4]2[NH:23][CH2:22][CH2:21][N:5]=2)=[CH:6][CH:7]=1)[NH2:1])[C:14]1[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=1Participants
4
Conditions
- Temperature
- 100 °C
Procedure
A mixture of 2-amino-4-(benzyloxy)-3-methoxybenzonitrile (144 g, 566 mmol) and sulfur (55 g, 1.7 mol) in ethylenediamine (800 mL) was degassed for 30 minutes then heated to 100° C. After 16 h the reaction mixture was cooled to room temperature and then filtered. The filtrate was concentrated under reduced pressure, diluted with a saturated sodium bicarbonate solution and extracted with EtOAc. The organic layer was washed with brine, dried (sodium sulfate), filtered and concentrated under reduced pressure. The resulting solids were recrystallized from EtOAc and hexanes to afford 3-(benzyloxy)-6-(4,5-dihydro-1H-imidazol-2-yl)-2-methoxyaniline (145 g, 86%): 1H NMR (DMSO-d6) δ: 7.27-7.48 (5H, m), 7.14 (1H, d), 6.92 (2H, m), 6.64 (1H, m), 6.32 (1H, d), 5.11 (2H, s), 3.67 (3H, s), 3.33 (2H, s).