1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → 2-(3-Iodo-4-methylphenyl)-6-((4-methylpiperazin-1-yl)methyl)-1H-benzo[d]imidazole

Participants

Reaction Steps

A mixture of 1-(3,4-diaminobenzyl)-4-methylpiperazine (10 mmol), 3-iodo-4-methylbenzoic acid (2.6 g, 10 mmol), EDCI (11 mmol), and HOBt (11 mmol) in dry DMF (25 mL) was stirred at ambient temperature for 24 hrs. The mixture was then evaporated in vacuo and the crude residue was dissolved in CH2Cl2 (100 mL) was washed with water (100 mL), brine (100 mL) and then dried by Na2SO4, filtered and concentrated. The residue obtained was dissolved in AcOH (30 mL) and heated at reflux for 3 hrs. The reaction mixture was eavporated in vacuo and the residue was purified by silica gel chromatography (eluent: 10% MeOH in CH2Cl2, MeOH was added 0.5% Et3N) to give a yellow solid (1.35 g, 30.3%). 1H NMR (300 MHz, CDCl3) δ: 8.50 (1 H, s), 7.94-7.97 (1 H, d, J=9.0 Hz), 7.53-7.56 (1 H, d, J=9.0 Hz), 7.52-7.55 (1 H, d, J=9.0 Hz), 7.30 (1 H, s), 7.20-7.23 (1 H, d, J=9.0 Hz), 3.60 (2 H, s), 2.54 (8 H, brs), 2.45 (3 H, s), 2.32 (3 H, s).

Provenance & Evidence