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-位上具有卤素原子或通过氧原子连接的可选取代烃基团的
喹啉-2-
羧酸,可在3-位上通过烃基团进行取代,并可在5、6、7和8位中的任意位置通过卤素原子、硝基或
氰基进行取代,或可选地通过氧原子直接或通过烃基团进行取代,且在3、4、5、6、7和8位的取代基中含有至少3个碳原子的总数,可与
金属,特别是
铜形成络合物。这些络合物可以通过有机溶剂从用
喹啉-2-
羧酸处理的
金属盐的
水溶液中提取。可以通过以下方法从相应的
4-羟基化合物制备
喹啉-2-
羧酸:(a)用
磷卤化物处理,必要时用醇或
酚的碱
金属衍
生物反应产物,并
水解酯基;或(b)在碱的存在下用烃基卤化物处理。