反应详情

温度

5 °C

49 g of 7-amino-1,4-benzodioxane-5-carboxylic acid, 200 ml of water and 50 ml of hydrochloric acid were introduced into a balloon flask provided with an agitator and a thermometer. The mixture was cooled to 5° C. and then a solution of 17.5 g of sodium nitrite in 38 ml of water was added. The suspension was then poured into a solution of 20 g of cuprous chloride in 75 ml of hydrochloric acid. The precipitate was dried off, washed and dissolved in a solution of 42 g of sodium bicarbonate in 420 ml of water. The solution was filtered and treated with 100 ml of hydrochloric acid. 50 g of 7-chloro-1,4-benzodioxane-5-carboxylic acid was produced (M.P.: 180° C.; yield: 92.7%).

1. customprovided with an agitator
2. customThe precipitate was dried off
3. washwashed
4. dissolutiondissolved in a solution of 42 g of sodium bicarbonate in 420 ml of water
5. filtrationThe solution was filtered
6. additiontreated with 100 ml of hydrochloric acid