Potassium Iodide → (R)-1-ethyl-3-(3-(methylamino)-1-phenylpropyl)-1H-benzo[d]imidazol-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

To a mixture of 1-[(1R)-3-chloro-1-phenylpropyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one (0.13 g, 0.4 mmol) and potassium iodide (0.2 g, 1.2 mmol) in methanol (5 mL) was added a solution of 33% methylamine in methanol (10 mL). The reaction solution was heated to 80° C. in a sealed tube for 3 hours and cooled to room temperature. The solvent was removed in vacuo and residue purified on a silica gel column (10-50% methanol in methylene chloride) to afford 1-ethyl-3-[(1R)-3-(methylamino)-1-phenylpropyl]-1,3-dihydro-2H-benzimidazol-2-one as an oil. The free base was dissolved in a minimum amount of ethanol and treated with a 2N ethereal solution of hydrochloric acid and stirred for 1 hour. The solvent was removed in vacuo and the residue was triturated with ether/dichloromethane to give 1-ethyl-3-[(1R)-3-(methylamino)-1-phenylpropyl]-1,3-dihydro-2H-benzimidazol-2-one HCl salt as a yellowish amorphous solid (30 mg, 22%). MS (ES) m/z 309.8.

Provenance & Evidence