2,4-Dichlorophenoxyacetic acid

In 1941, R. Poconi, an American, published a synthetic method of 2,4-D. Although the product is relatively old, it is still a hot product at present. It is widely used in Maize field, wheat field, sorghum field, sugarcane field, paddy field, Millet Field and grasses lawn to control broad-leaved weeds, and trace amount is used in some vegetable fields to preserve flowers and fruits.

2,4-D pure white crystal. Melting point 138 C, boiling point 160 C (53Pa). Soluble in organic solvents such as ethanol, acetone, ether and benzene, insoluble in water.

2,4-D was synthesized by chlorination of phenol to 2,4-dichlorophenol, which condensed with chloroacetic acid in the presence of sodium hydroxide to form 2,4-D sodium salt, and then acidified to 2,4-D original drug.