反应详情

To a solution of 220 g of 2-(2-carboxy-4-chlorophenoxy) propionic acid in 550 ml of concentrated sulfuric acid is added dropwise a mixed liquid of 44 ml of fuming nitric acid and concentrated sulfuric acid under stirring with keeping at a temperature below 10° C. After the addition, the reaction mixture is stirred below 10° C. for 3 hours and poured into 10 1 of ice-cold water. The precipitated crystals are collected by filtration, washed with 2 1 of water four times and them dried to give 190 g of 2-(2-carboxy-4-chloro-6-nitrophenoxy)propionic acid, melting at 190° C.

1. customwith keeping at a temperature below 10° C
2. additionAfter the addition
3. stirringthe reaction mixture is stirred below 10° C. for 3 hours
4. additionpoured into 10 1 of ice-cold water
5. filtrationThe precipitated crystals are collected by filtration
6. washwashed with 2 1 of water four times and them
7. customdried