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.
在4位有一个卤素原子或可选择通过氧原子连接的一个可选择取代的烃基团的
喹啉-2-
羧酸,3位可选择取代的烃基团,5、6、7和8位中的任一位置可选择通过卤素原子、硝基或
氰基或可选择取代的烃基团直接或通过氧原子取得,并且在3、4、5、6、7和8位的取代基中含有至少3个碳原子的
金属络合物,特别是
铜。这些络合物可以通过有机溶剂从经过
喹啉-2-
羧酸处理的
金属盐
水溶液中提取。
喹啉-2-
羧酸可以通过以下方法从相应的
4-羟基化合物制备:(a)与
磷卤素处理,必要时将产物与醇或
酚的碱
金属衍
生物反应并
水解酯基团,或(b)在碱存在的情况下与烃卤素处理。