(2-羟乙基)三苯基鏻甲基橙的合成

Synthesis of(2-Hydroxyethyl) Triphenylphosphonium Methyl Orange

以三苯基膦和2-氯乙醇为原料,通过亲核取代反应合成了氯化(2-羟乙基)三苯基鏻;以甲基橙与硝酸银经复分解反应制备了甲基橙银盐;以所合成的氯化(2-羟乙基)三苯基鏻为中间体,与甲基橙银盐经过阴离子交换,合成新型酸碱指示剂——(2-羟乙基)三苯基鏻甲基橙.通过核磁共振谱和高分辨质谱确认了产物及反应中间体的结构,并对产物的熔点及其在不同溶剂中的溶解性能进行了研究.研究表明,该新型酸碱指示剂具有典型的离子液体特征,其水/油溶解性得到有效调控,其使用范围较甲基橙得以拓展.采用适当的溶剂,可以实现于水相酸碱指示后的萃取回收.

(2-Hydroxyethyl)triphenylphosphonium chloride was synthesized from triphenylphosphine and 2-chloroethanol by nucleophilic substitution reaction,and methyl orange silver salt was prepared by double decomposition reaction of methyl orange and silver nitrate.Based on that,a new acid-base indicator,(2-hydroxyethyl)triphenylphosphonium methyl orange,was synthesized by anion exchange.The structures of product and reaction intermediates were confirmed by 1H NMR, 13 C NMR and HR-MS.The melting point of product and its solubility in different solvents were studied.The results show that the new acid-base indicator has typical characteristics of ionic liquids.Its solubility is effectively regulated,and its application range is wider than that of methyl orange.With proper solvent,the extraction and recovery of the new acid-base indicator can be retrievde after acid-base indication in water phase.