Sodium hydride → 2-[(1-Methyl-3-pyrrolidinyl)thio]-3-pyridinecarboxylic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred suspension of 80 g (2 mole) of 60% sodium hydride (in mineral oil) in 800 ml of dry dimethylformamide, all heated to 60° C. and using nitrogen gas flow was added dropwise, a solution of 157.0 g (1 mole) of 2-chloronicotinic acid and 117 g (1 mole) of 1-methyl-3-pyrrolidinethiol in 300 ml of dimethylformamide at a rate which maintained a temperature of 60°-67° C. The mixture was heated to 65° C. for 6 hr and allowed to stand overnight at room temperature and then filtered. The collected solid was suspended in one liter of isopropyl alcohol and hydrogen chloride was bubbled into the suspension until a pH of 6.2 was reached. The mixture was brought to a boil and filtered. The solid was dissolved in 2 liters of water and extracted with isopropyl ether. The pH was adjusted to 6.0 and the solution was concentrated to a volume of 800 ml and placed in a refrigerator. The resulting solid (85 g) collected by filtration, was a mixture consisting of about 85% of the title compound and 15% sodium chloride. A sample portion of this was crystallized once from ethanol and twice from isopropyl alcohol-water. The recrystallized product decomposed at about 225° C.

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