Multigram chromatography-free synthesis of octa(ethylene glycol) p-toluenesulfonate

Here we report a detailed synthetic procedure for monodisperse octa(ethylene glycol) p-toluenesulfonate, a member of the heterobifunctional oligo(ethylene glycol) derivatives family. The method offers completely chromatography-free workup and purification, resulting in higher yields and a lower cost than any of the alternative strategies. We also introduce several upgrades, simplifying the method even more, and discuss the chromatography-free design limitations.