摘要 |
A process for making phenylene dioxydiacetic acid comprises (a) contacting a dihydroxybenzene under reaction conditions with a salt of haloacetic acid in a solution without adding a haloacetic acid to produce a salt of phenylene dioxydiacetic acid; and (b) optionally converting the salt of phenylene dioxydiacetic acid to free phenylene dioxydiacetic acid. In some embodiments, 1,3-phenylene dioxydiacetic acid (RDOA) is made by reacting resorcinol with sodium chloroacetic acid in a reaction mixture with a pH in the range of about 7 to about 11 and at a temperature from about 70° C. to 105° C. By adjusting the reactions conditions, a relatively high yield of 1,3-phenylene dioxydiacetic acid (i.e., greater than 80%) is obtained. The purified acid can be used in the synthesis of polyester, such as polyethylene terephthalate. |