反应详情

5-Amino-6-chloroquinaldine (4 g) was dissolved in 40 ml of concentrated hydrochloric acid and the resulting solution was cooled with ice. Then, a solution of 2.1 g of sodium nitrite dissolved in 5 ml of water was added thereto dropwise while ice-cooling. After continuing the reaction at the same temperature as above, the reaction mixture was added to a solution of 7 g of cuprous chloride dissolved in 15 ml of concentrated hydrochloric acid and the resulting mixture was allowed to react on a water bath at a temperature of 50° C. for 1 hour, during which time vigorous formation of nitrogen gas was observed. Subsequently, the reaction mixture was cooled, rendered alkaline with 30% sodium hydroxide, and filtered and extracted using 300 ml of chloroform and Celite (diatomaceous earth). After drying over anhydrous sodium sulfate the chloroform fraction was concentrated and recrystallized from a mixture of isopropanol and water to give 3.5 g of 5,6-dichloroquinaldine as white needles having a melting point of 84° to 85° C.

1. temperaturethe resulting solution was cooled with ice
2. additionwas added
3. temperaturedropwise while ice-cooling
4. customthe reaction at the same temperature as above, the reaction mixture
5. customto react on a water bath at a temperature of 50° C. for 1 hour, during which time vigorous formation of nitrogen gas
6. temperatureSubsequently, the reaction mixture was cooled
7. filtrationfiltered
8. extractionextracted
9. dry with materialAfter drying over anhydrous sodium sulfate the chloroform fraction
10. concentrationwas concentrated
11. customrecrystallized from a mixture of isopropanol and water