2-(3′-sulphobenzoyl)pyridine thiosemicarbazone and phenyl thiosemicarbazone as spectrophotometric analytical reagents

Abstract

The synthesis, characteristics, properties and metal-ion interactions of 2-(3′-sulphobenzoyl)-pyridine thiosemicarbazone and phenyl thiosemicarbazone have been studied. These substances exhibit three p K values in aqueous solution, and form water-soluble chelates with high molar absorptivities, which may be used in analysis, especially the iron(II) chelates (λ max 620–630 nm). The behaviour of the iron-reagent systems has been investigated.