Hydrochloric Acid → 4-Chloro-1H-benzo[d]imidazol-5-amine

Participants

Reaction Conditions

Reaction Steps

58 mg (0.277 mmol) of N-(4-chloro-1H-benzimidazol-5-yl)acetamide (24-1) was suspended in a mixture of water, ethanol and concentrated HCl (0.06:1:0.4) for a total of 1 mL. The suspension was stirred and heated at 85° C. under nitrogen for 1 hour and after this time everything was soluble. The heat was turned off the solution was stirred overnight. The reaction was quenched with saturated NaHCO3. The pH was adjusted to 8 by adding solid NaHCO3 and Na2CO3. Extracted the reaction with ethyl acetate, dried, filtered and evaporated to recover the desired product 24-2. MS (M+1): measured 168.2; theoretical 167.0. 1H NMR (CD3OD): 6.75 (dd, 1H), 7.37 (d, 1H), 7.93 (s, 1H).

Provenance & Evidence