Patent ID: 7538244

Claim:
A process for preparing an n-alkoxy aromatic acid from a hydroxy aromatic acid that is described generally by the structure of Formula I (COOH) m —Ar—(OH) n I wherein Ar is a C 6 ˜C 20 arylene radical, n and m are each independently a nonzero value, and n+m is less than or equal to 8, comprising the steps of (a) contacting a halogenated aromatic acid that is described generally by the structure of Formula II, (COOH) m —Ar—(X) n II wherein each X is independently Cl, Br or I, and Ar, n and m are as set forth above, with a base in water to form therefrom the corresponding m-basic salt of the halogenated aromatic acid in water; (b) contacting the m-basic salt of the halogenated aromatic acid with a base in water, and with a copper source in the presence of an amine ligand that coordinates to copper, to form the m-basic salt of a hydroxy aromatic acid from the m-basic salt of the halogenated aromatic acid at a solution pH of at least about 8, wherein the ratio of molar equivalents of ligand to molar equivalents of hydroxy aromatic acid is less than or equal to about 0.1, and the ligand comprises, when it is a tetramine, at least one primary or secondary amino group; (c) optionally, separating the m-basic salt of the hydroxy aromatic acid from the reaction mixture in which it is formed; (d) contacting the m-basic salt of the hydroxy aromatic acid with acid to form therefrom an n-hydroxy aromatic acid; and (e) converting the n-hydroxy aromatic acid to an n-alkoxy aromatic acid.