Redox reactions in non-aqueous media: determination of organic isothiocyanates alone, in formulations and in important mixtures.
A simple potentiometric method for the determination of organoisothiocyanates is described. The isothiocyanate is treated in acetonitrile medium with an excess of primary amine to convert it into a substituted thiourea and the surplus amine is converted into a dithiocarbamate by addition of carbon disulphide. The solution is then titrated with a copper(II) solution in acetonitrile. The three-step titration curve enables the results to be calculated on the bash of the dithiocarbamate and/or thiourea formed. The method has been successfully applied to the analysis of a commercial insecticide formulation based on isothiocyanate and important mixtures containing isothiocyanates.
Analytical applications of copper(II) and copper(I) in acetonitrile: potentiometric and spectrophotometric determination of dithiocarbamates.
The use of copper(II) perchlorate and tetra-acetonitrilocopper(I) perchlorate (in acetonitrile) for the potentiometric and spectrophotometric determination of dithiocarbamates in acetonitrile medium is described. The proposed methods are simple, accurate and reliable and show promise of wide applicability. They are recommended for routine determination of dithiocarbamates. Their advantages over the carbon disulphide evolution method, commonly employed for the determination of these compounds, are discussed.
Polarography of some sulphur-containing compounds : Part XII1.Anodic waves of dialkyldithiocarbamates
Abstract Dialkyldithiocarbamates give only a one-electron anodic wave. The various adsorption phenomena are probably caused by varying orientation of the mercury compounds on the electrode surface; the irregular i-t curves recorded at —0.04 V and the anomalous behaviour of the anodic current between +0.2 V and —0.4 V can be interpreted as the behaviour of an adsorbed film at the electrode. Analytical measurements are best made in 60% ethanolic 0.1 M sodium hydroxide media at concentrations of about 10-5 M dialkyldithiocarbamate; a method is given for the analysis of the monoalkyl and dialkyl compounds in mixtures.