Ethyl orthopropionate → HCID 69506738, compound

Participants

Reaction Steps

Ethyl 3-[(3-aminoquinolin-4-yl)amino]-2,2-dimethylpropanoate (see Example 26 Parts A through D, 3.6 g, 12 mmol) was treated according to a modification of the method described in Part B of Example 8 using triethyl orthopropionate in lieu of trimethyl orthobutyrate. Prior to the addition of triethyl orthopropionate (4.0 mL, 20 mmol) and pyridinium p-toluenesulfonate (0.030 g), the reaction was heated at reflux for 15 minutes. After the reaction was heated at reflux for three hours, it was concentrated under reduced pressure and found to be incomplete by 1H NMR. The oil was dissolved in toluene (100 mL), and concentrated sulfuric acid (one drop) was added. The reaction was heated at reflux for two hours and allowed to cool. Triethylamine (5 mL) was added, and the reaction was heated at reflux for two hours, allowed to cool to ambient temperature, washed with saturated aqueous sodium bicarbonate (2×35 mL), dried over potassium carbonate, filtered, and concentrated to provide 3.6 g of ethyl 3-(2-ethyl-1H-imidazo[4,5-c]quinolin-1-yl)-2,2-dimethylpropanoate as an oil.

Provenance & Evidence