Van Zee, Nathan J.

Phase-vanishing reactions are triphasic reactions that involve a reagent, a liquid perfluoroalkane, and a substrate. In a phase-vanishing reaction with PTFE (polytetrafluoroethylene) tape as the phase screen instead of a liquid perfluoroalkane, there is no limitation related to the density of a phase, and the denser phase can be in the top layer. Additionally, PTFE tape is inexpensive, easy to use, and reusable. In this work we qualitatively described PTFE tape's thickness, stretching characteristics, and permeability. We investigated the phase-vanishing PTFE method's usefulness both in known transformations and also in a novel nucleophile-assisting leaving group (NALG) reaction with menthol, thionyl bromide, and zirconium(IV) chloride. We successfully used PTFE tape as a phase screen in bromination, bromolactonization, esterification, chemiluminescence, and tandem bromination/esterification phase-vanishing reactions. We found that the PTFE tape is an effective phase screen and useful in performing a slow addition of a reagent.