Reaction #72821

Reaction equation

methyl 2,3-diamino-5-(4-morpholinyl)benzoate

urea

→

desired product

Yield 62.0%

methyl 6-(4-morpholinyl)-2-oxo-2,3-dihydro-1H-benzimidazole-4-carboxylate

Yield 62.0%

Solvents

DCM

DMF

Conditions

Workup

1. 1
   Temperaturethe mixture was cooled to room temperature
2. 2
   Washwashed with water (50 mL×2)
3. 3
   Dryingdried over anhydrous Na2SO4
4. 4
   Filtrationfiltered
5. 5
   Concentrationconcentrated in-vacuo
6. 6
   OtherThe residue was then purified by chromatography on silica (eluted with EtOAc)

Procedure

To a solution of methyl 2,3-diamino-5-(4-morpholinyl)benzoate, prepared as described in Example 45, step a (11.0 g, 4.0 mmol) in DMF (50 mL) was added urea (720 mg, 12 mmol) and the mixture was heated to 170° C. for 4 h. When analysis by TLC showed no starting material remaining, the mixture was cooled to room temperature then diluted with DCM (200 mL), washed with water (50 mL×2) and dried over anhydrous Na2SO4, filtered and concentrated in-vacuo. The residue was then purified by chromatography on silica (eluted with EtOAc) to afford the desired product as a dark-yellow solid (690 mg, 62%).

Source