Detection of a covalent-ionic carbinolamine intermediate in aqueous media by SDTLC on silica gel plates

Autor: Oscar Alberto Locani, Isabel A. Perillo, Alejandra Salerno, Ana M. Reverdito, Mariano García
Rok vydání: 2007
Předmět:
Zdroj: Journal of Planar Chromatography – Modern TLC. 20:227-230
ISSN: 1789-0993
0933-4173
Popis: When the components of a reaction mixture cannot be quantified by UV–visible spectrophotometry, because the λ max values of their absorption bands overlap, the components can be separated and quantified by spectrodensitometric thin-layer chromatography (SDTLC). In this work an aminolysis reaction mixture in aqueous medium was studied by TLC on silica gel plates with densitometric detection. The reaction, an intramolecular rearrangement involving migration of an acyl group, was studied by monitoring a carbinolamine intermediate for which λmax was identical with those of the substrate and product. SDTLC not only enabled detection of all three components of the mixture when the plate was developed but also enabled detection of covalent and ionic forms of the reaction intermediate by comparison of their absorbance/reflectance spectra with those of structurally related imidazolidine and amidinium salt derivatives, respectively, used as model compounds. Kinetic studies, among others, may also be performed by SDTLC to determine the mechanism of the reaction.
Databáze: OpenAIRE