Trisodium Hexanitrocobaltate, Na3[Co(NO2)6], as Reagent in Organic Analysis

Abstract

Sodium hexanitrocobaltate reacts with phenolic compounds under formation of Co chelates of corresponding o-nitrosophenols or under formation of nitrophenols, depending on reaction conditions. With phenothiazine derivatives in phosphoric acid, oxidation takes place and corresponding radical ions are formed. The formation of nitrophenols and the radical ions of phenothiazine is used for spectrophotometric determinations. The Co chelates and ion associates can be used for the indirect determination of phenols or organic cations by atomic absorption spectrometry. Formation of ion associates of the [Co(NO₂)₆]^3- anion with organic cations is also utilized in analysis.