Citric Acid → HCID 21876503, compound

Participants

Reaction Steps

To a stirred solution of 2-[4-(5-amino-2-ethyl-1H-benzimidazol-1-yl)phenyl]ethyl propionate (step 4, 1.18 g, 3.50 mmol) in dichloromethane (20 mL) was added methanesulfonyl chloride (0.40 mL, 5.25 mmol) and pyridine (0.42 mL, 5.25 mmol) at room temperature. After stirring for 6 h, the mixture was poured into 10% aqueous citric acid (100 mL) and extracted with ethyl acetate (100 mL). The aqueous layer was made basic with saturated aqueous sodium bicarbonate (100 mL) and extracted with ethyl acetate (100 mL). The combined organic extracts were washed with brine (100 mL) and dried (MgSO4), and concentrated to afford 1.28 g (88%) of the title compound as brown amorphous: 1H-NMR (CDCl3) δ 8.47 (1H, s), 7.66 (1H, d, J=1.7 Hz), 7.50 (2H, d, J=8.4 Hz), 7.42 (1H, dd, J=2.0, 8.8 Hz), 7.41 (2H, d, J=8.4 Hz), 7.09 (1H, d, J=8.8 Hz), 4.39 (2H, t, J=7.0 Hz), 3.09 (2H, t, J=6.8 Hz), 3.00 (2H, q, J=7.7 Hz), 2.36 (2H, q, J=7.7 Hz), 1.42 (3H, t, J=7.7 Hz), 1.15 (3H, t, J=7.5 Hz).

Provenance & Evidence