反应详情

To a flame-dried 100 mL round-bottom flask equipped with a stir bar and a reflux condenser were added 4-chloro-1,2-phenylenediamine (1 g; 7.0 mmoles), 3-nitro-1,2-phenylenediamine (1.07 g; 7.0 mmoles), diethyl malonimidate dihydrochloride (1.62 g; 7.0 mmoles) and ultra pure acetic acid (ca. 35 mL; from Aldrich) under a nitrogen atmosphere. The mixture was refluxed for 2 hours and then cooled to room temperature, and the acetic acid was removed (via roto-vap). The residue was suspended and sonicated (ca. 5 minutes) in 0.5 M HCl, and the remaining precipitate was removed by filtration and dried (P2O5 and high-vacuum). This procedure gave 0.8 g of the desired 2-[(5-chloro-1H-benzimidazol-2-yl)methyl]4-nitro-1H-benzimidazole as a dark brown solid in 35% yield. It gave one major peak by HPLC and had mass spec (FB+): m/z=328.0 [M+].

1. customTo a flame-dried 100 mL round-bottom flask equipped with a stir bar and a reflux condenser
2. temperatureThe mixture was refluxed for 2 hours
3. customthe acetic acid was removed (via roto-vap)
4. customsonicated (ca. 5 minutes) in 0.5 M HCl
5. customthe remaining precipitate was removed by filtration
6. dry with materialdried (P2O5 and high-vacuum)