Selectivity in Tip-Induced Skeletal Editing via Heteroatom Substitution

Skeletal editing enables precise structural modifications of molecules at late stages of a synthetic sequence. We recently demonstrated skeletal editing on a single-molecule scale. Voltage pulses applied by the tip of a scanning probe microscope to an oxygen-containing seven-membered heterocycle led to both oxygen deletion and ring-contraction rearrangement reactions. An open question is whether selective skeletal editing of a heterocyclic core can be achieved by the choice of heteroatom. Here we show that tip-induced reactions of an analogous sulfur-containing seven-membered ring mainly result in sulfur deletion. Our results demonstrate that the combination of tip-induced chemistry and heteroatom selection in the molecular design is a powerful strategy for single-molecule skeletal editing, potentially enabling diverse structural transformations of heterocyclic frameworks.