Triethylamine → Methyl 2-(dimethylcarbamoyl)pyridine-4-carboxylate

Participants

Reaction Steps

A mixture of compound 26 (73 g, 0.4 mole), thionyl chloride (88 ml, 1.2 mole) in toluene (200 ml) was heated at reflux for 3 hours. The excess thionyl chloride was removed at an atmospheric pressure. Then toluene was removed under reduced pressure. The resulting light green acid chloride 27 was used without further purification. A solution of acid chloride 27 in CH2Cl2 (100 ml) was added to a suspension of dimethylamine hydrochloride (98.6 g, 1.2 mole) and triethylamine (1.3 mole) in CH2 Cl2 (200 ml) at 0° C. dropwise over a period 10 minutes and stirred for 1 hour at room temperature. Water (200 ml) was added to the reaction mixture, water layer was extracted with CH2Cl2. The combined organic layers were washed with 1N NaOH, brine, dried over MgSO4 and concentrated down. The crude solid was purified by silica gel short column chromatography (EtOAc as eluent) to give compound 28 (47 g, 226 mmole, 56%).

Provenance & Evidence