Titration of alkyllithiums with a simple reagent to a blue endpoint
نویسندگان
چکیده
Reaction of readily available N-benzylbenzamide (I) with a slight excess of BuLi produces a deep blue dianion. Under suitable conditions (THF, -40*(2), 1 may be used as a stoichiometric reagent to titrate n-BuLl, s-BuLi, and t-BuLi with good precision. Less reactive alkyllithiums (MeLi and MeLi, LiBr), aryllithiums, and LDA may be titrated at higher temperatures ( 20 to 0°C). Titres are comparable to those obtained using the Gilman double titration method, and there appears to be no interference from alkoxides. © 1997 Elsevier Science S.A.
منابع مشابه
A convenient method for determining the concentration of hydrogen in water: use of methylene blue with colloidal platinum
A simple titration (oxidimetry) method using a methylene blue-platinum colloid reagent is effective in determining the concentration of hydrogen gas in an aqueous solution. The method performs as effectively as the more complex and expensive electrochemical method.
متن کاملNon Aqueous Titration for the Determination of Azelaic Acid: Introduction and Method Validation
Alpha-hydroxylic acids are widely used in the treatment and control of skin disorders. Azelaic acid is a naturally occuring Alpha-hydroxy acid that can be formed endogenously from long-chain dicardoxylic acids, metabolism of oleic acid or omega oxidation of mono carboxylic acids. It shows bacteriostatic and bactericidal activities against aerobic and anaerobic micro-organisms present on acne-be...
متن کاملELISA Analyzer •, a Software to Analyze and Optimize ELISA Data
ELISA data is usually handled in the MS Excel worksheets through different methods and different formulas. Accurate and precise calculations of the data is time consuming and tedious. ELISA Analyzer was developed with a user friendly interface to streamline titration and analysis of the data obtained from ELISA and improve rapid and lucid presentation of the results. The software can also hel...
متن کاملMolecular interactions between charged macromolecules: colorimetric detection and quantification of heparin with a polydiacetylene liposome†
The molecular interactions between an artificial liposome decorated with cationic sites and heparin, a biomacromolecule with dense negative charge, have been studied for the first time. Heparin is used as an anticoagulant during cardiovascular surgery or to avoid thrombosis. Overdose of heparin, however, can induce complications such as hemorrhage or thrombocytopenia, making it important to mon...
متن کاملSimple Modification of Karl-Fischer Titration Method for Determination of Water Content in Colored Samples
The most commonly used technique for water content determination is Karl-Fischer titration with electrometric detection, requiring specialized equipment. When appropriate equipment is not available, the method can be performed through visual detection of a titration endpoint, which does not enable an analysis of colored samples. Here, we developed a method with spectrophotometric detection of a...
متن کامل