Abstract
For the purpose of determining the composition of the products in the reactions of lower aliphatic amines with sulfur trioxide, an analytical method was developed which was based on a combination of anion-exchange chromatographic separation and complexometric titration of components.
A reaction mixture obtained in the reaction of methylamine with sulfur trioxide was dissolved in water and diluted to 250 ml. An aliquot of this solution was applied upon an Amberlite CG-400 (Cl-form) column. Then, 0.15 M NaCl was passed through the column at a flow rate of 1.0 ml per min. N, N '-Dimethylsulfamide was first eluted, followed by N-methylsulfamate. Sulfate was then eluted with 0.5 M NaCl, and finally N-methylimidodisulfate with 1 M NaCl.
Each fraction was treated with 1 N HCl and 6 M NaNO2 solution. The sulfate ion formed was then precipitated in the usual manner by adding 0.01 M BaCl2, and after pH adjustment, the excess of barium ion was back-titrated in the presence of Zn-EDTA with 0.01M EDTA by use of Eriochrome Black T as an indicator.
This method proved to be simple, accurate and widely applicable.
Paper and thin-layer chromatography were also described.
