Preparative chromatography for obtaining pure samples of rosaniline, magenta II, and new fuchsine

A simple low pressure liquid chromatographic method is reported that can separate the basic fuchsine homologues, rosaniline, magenta II and new fuchsine from an impure commercial dye. The chromatographic purity of the separated dyes is > 90%. All homologues were obtained in multi-milligram amounts per chromatographic run; precise yields depend on the composition of the starting material and potentially may be greater. This is a useful preparative procedure for generating chromatographically pure samples of basic fuchsine homologues, especially those that cannot be obtained in pure form by direct synthesis.