6533b839fe1ef96bd12a6315

RESEARCH PRODUCT

Reflux reactions for chromatography

subject

description

Reactions under pressure are mainly used to prepare derivatives before chromatographic analysis because of the lack of microequipment. A ml-refluxer has been designed to allow reactions under atmospheric pressure for volumes from 0.2 to 5 cm3. The reaction temperature is determined by the boiling point of the solvent thus derivatives of heat sensitive compounds can be made in the micro scale. With the aid of the ml-refluxer large series of derivatisations can be carried out and hence the reaction parameters can be optimized. This is shown at the example of the alkylation of barbituric acids for gas chromatography, where thus only N,N′-derivatives were obtained. The reliability of the apparatus and the reproducibility of the derivatisation method have been established. Thus the ml-refluxer is suitable as a supplement for the microrefluxer when reflux reactions with larger end volumes are needed for different analytical runs.