Novel Borylene Synthon: From Design, Synthesis to Application

Borylene (R–B:) is a concept derived from carbene, which refers to a carbon species with only six electrons in its valence shell. As a class of compounds extensively studied in main group chemistry, carbenes have long demonstrated broad applications in fields such as catalysis, synthesis, materials science, and pharmaceuticals. In contrast, borylenes—owing to their extremely high reactivity that is difficult to control—have yet to be widely applied in areas such as catalysis and synthesis. Even the free state of borylenes (R–B:) has not been isolated and stabilized. Notably, not only are carbon–boron bonds widely utilized for further functionalization, but numerous high-value pharmaceutical molecules also contain boron atoms. Therefore, employing borylenes as boron-inserting synthons, and even applying them to molecular skeleton editing via boron atom insertion, holds significant research value and application potential.