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有机碱盐在二相系统(氯仿与醋酸盐缓冲液)中可用四苯硼钠在适当指示剂存在下进行滴定。作者对反应物的克分子比及定量关系作了研究。方法基于生成氯仿可溶性有机碱-指示剂络合物,而四苯硼钠则与有机碱生成更稳定的络合物。通过等当点后,四苯硼钠从碱指示剂络合物中取代指示剂而使溶液变色。方法:取样品溶液10毫升(含0.5～1.5毫克),加20毫升醋酸盐缓冲液pH 1.71(50毫升1N醋酸钠加55毫升1N盐酸,加水至250毫升),60毫升氯仿,3滴金莲橙OO或间胺黄指示剂(100毫克溶于100毫升乙醇
The organic base salts can be titrated with sodium tetraphenylborate in the presence of a suitable indicator in a biphasic system (chloroform and acetate buffer). The authors studied the molar ratio of reactants and their quantitative relationship. The method is based on the formation of a chloroform-soluble organic base-indicator complex, whereas sodium tetraphenylborate generates a more stable complex with an organic base. After the equivalent point, sodium tetraphenylborate displaces the indicator from the base indicator complex to discolor the solution. Methods: Take 10 ml of sample solution (containing 0.5-1.5 mg), add 20 ml of acetate buffer pH 1.71 (50 ml of 1N sodium acetate and 55 ml of 1N hydrochloric acid, add water to 250 ml), 60 ml of chloroform, Orange OO or m-amine indicator (100 mg in 100 mL of ethanol