Merging Rh(III)-Catalyzed C–H Activation andStrain Release of Bicyclo[1.1.0]butanes: Modular Access to ConjugatedDienes

We report a Rh(III)-catalyzed C–H activation and strain-release cascade that merges inert C–H bond functionalization with the ring opening of bicyclo[1.1.0]butanes (BCBs) to directly access conjugated dienes. The reaction leverages the unique alkene-like reactivity of the BCB bridgehead bond and the versatility of Rh(III) catalysis to enable simultaneous C–H cleavage and C–C scission, offering a new disconnection for diene synthesis in up to 95% yield. The resulting conjugated diene scaffolds demonstrate versatile synthetic utility, including D–A cycloaddition, [3+2] cyclization, and thia-Michael addition reactions. Importantly, this work represents the first use of BCBs as diene precursors, expanding their reaction manifold and providing a new avenue for the development of novel transformations.