Our latest paper is now out in @J_A_C_S! Carbenoid species have had a profound impact on synthetic chemistry and are now indispensable tools for building molecular complexity. Yet one of their smallest main-group relatives, the borylene, has remained notably absent from the synthetic chemist’s toolbox, despite its fascinating and highly unusual electronic structure. Since starting our group, one of our major goals has been to address this challenge and explore the synthetic potential of borylenes. In our work, we report an exceptionally mild and modular approach to borylene generation from simple, readily diversifiable precursors. We then use this platform to explore the cycloaddition chemistry of borylenes with alkenes, providing access to unique fused borirane architectures. This reactivity developed into a chemo- and regioselective strategy for alkene functionalization, with the resulting boriranes serving as versatile synthetic intermediates. We further demonstrate its utility through application to the formal synthesis of natural products. We believe this work takes borylenes one step closer to becoming practical species for synthetic chemistry, and opens the door to many new transformations yet to be discovered. pubs.acs.org/jacsat/article/…