Quinoline 2 carboxylic acids used in metal extraction processes

Abstract

Quinoline-2-carboxylic acids having in the 4-position a halogen atom or an optionally substituted hydrocarbyl group attached through an oxygen atom, optionally substituted by a hydrocarbyl group in the 3 position and optionally substituted in any of the 5, 6, 7 and 8 positions by halogen atoms, nitro or cyano groups, or optionally substituted hydrocarbyl groups each attained directly or through an oxygen atom, and containing in the substituents in the 3, 4, 5, 6, 7 and 8 positions a total of at least 3 carbon atoms form complexes with metals, especially copper. These complexes may be extracted by organic solvents from aqueous solutions of metal salts treated with the quinoline-2-carboxylic acids. The quinoline-2-carboxylic acids may be prepared from the corresponding 4-hydroxy compounds by (a) treating with a phosphorus halide, if necessary reacting the product with the alkali metal derivative of an alcohol or phenol and hydrolysing the ester group or (b) treating with a hydrocarbyl halide in presence of a base.

Dependencies are inferred from the claim text.