Reaction #72111

Reaction equation

4-Chloro-5-ethyl-1H-imidazole-2-carboxylic acid

1-hydroxybenzotriazole

1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride

triethylamine

Ethyl 3-(4-aminocyclohex-1-enyl)benzoate

→

title compound

Yield 76.2%

Ethyl 3-{4-[(4-chloro-5-ethyl-1H-imidazole-2-carbonyl)amino]cyclohex-1-enyl)benzoate

Yield 76.2%

Solvents

ethyl acetate

N,N-dimethylacetamide dichloromethane

1/1

water TFA

Conditions

Workup

1. 1
   Washwashed with brine
2. 2
   Dryingdried over magnesium sulfate
3. 3
   OtherThe solvent was evaporated under reduced pressure
4. 4
   OtherThe resulting residue was purified by silica gel column chromatography (elution solvent: hexane/ethyl acetate=1/1)

Procedure

Ethyl 3-(4-aminocyclohex-1-enyl)benzoate obtained in Example (951c) (120 mg, 0.49 mmol) was dissolved in a mixed solution of N,N-dimethylacetamide/dichloromethane=1/1 (10 mL). 4-Chloro-5-ethyl-1H-imidazole-2-carboxylic acid (described in Example 1d, 86 mg, 0.49 mmol), 1-hydroxybenzotriazole (100 mg, 0.735 mmol), 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (141 mg, 0.735 mmol) and triethylamine (102 μL, 0.735 mmol) were added, and the mixture was stirred at room temperature overnight. The reaction solution was diluted with ethyl acetate, washed with brine, and then dried over magnesium sulfate. The solvent was evaporated under reduced pressure. The resulting residue was purified by silica gel column chromatography (elution solvent: hexane/ethyl acetate=1/1) to obtain 150 mg of the title compound as a white solid (76%).

Source