Potassium Iodide → HCID 60209559, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 0.16 g (2.2 mmol) of sodium nitrite dissolved in 3.5 ml of water is slowly added to a solution, cooled to 0° C., of 0.47 g (1.5 mmol) of 2-(methylamino)-2-oxoethyl 4-(5-amino-2-pyridyl)-1-piperazinecarboxylate, prepared in step 5.4, in 15 ml of aqueous sulfuric acid solution (0.33N). Stirring is continued at about 0° C. for half an hour, and 0.83 g (5 mmol) of potassium iodide is slowly added. Stirring is continued at this temperature for half an hour and the reaction mixture is then maintained at 85° C. for 2 hours. After cooling to room temperature, the reaction medium is basified to pH=14, by adding saturated aqueous sodium bicarbonate solution. The aqueous phase is extracted three times with dichloromethane, the combined organic phases are washed with aqueous 35% thiosulfite solution, water, brine and dried over sodium sulfate. The filtrate is concentrated under reduced pressure and the residue thus obtained is purified by chromatography on silica gel, eluting with a 98/2 mixture of dichloromethane and methanol. After washing with diisopropyl ether, 0.35 g of product is obtained in the form of a beige-colored solid, and is used without further purification in the following step.

Provenance & Evidence