Indirect nonaqueous titration of hydrochlorides of nitrogenous bases

✍ Scribed by Sobhi A. Soliman; Hassan Abdine; Nashaat A. Zakhari

• Publisher: John Wiley and Sons
• Year: 1974
• Tongue: English
• Weight: 384 KB
• Volume: 63
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.2600631123

✦ Synopsis

An indirect nonaqueous titrimetric method was devised for the determination of the hydrochlorides of nitrogenous bases. The chloride-ion interference was prevented without the use of a mercuric acetate reagent. The method depends on the treatment of a solution of the hydrochloride of the organic base with an excess of standard aceteous perchloric acid solution and the hydrogen chloride displaced is removed by boiling. Residual excess perchloric acid is determined by titration against the basic titrant so- dium acetate in glacial acetic acid, using either potentiometric or visual end-point detection with a crystal violet indicator. The proposed method was applied successfully to the determination of several hydrochlorides of nitrogenous bases. The mean percent recoveries obtained indicate that the proposed method is equivalent in accuracy and precision to the nonaqueous titrimetric method most commonly used by official compendia for this determination. Potentiometric titrations showed that the point of the maximum inflection in the titration curves coincided with the appearance of the violet color of the indicator.

Keyphrases Nitrogenous bases, hydrochlorides-indirect nonaqueous titration, method compared to compendial methods Nonaqueous titration, indirect-hydrochlorides of nitrogenous bases, compared to cornpendial methods 0 Titrations, indirect nonaqueous-hydrochlorides of nitrogenous bases, compared to compendial methods