Autonomous Suzuki–Miyaura Coupling via Solid-State Self-Assembly: A Solvent-Free, Ligand-Free, and Mechanochemistry-Independent Paradigm for Sustainable C–C Bond Formation

The Suzuki–Miyaura coupling, while revolutionizing C–C bond construction in pharmaceuticals (anticancer agents, antihypertensives, and ARV drugs), liquid crystals, and advanced materials, remains constrained by its reliance on bulk organic solvents—a possible environmental burden, safety risks, and 30–45% solvent-related production costs. Although mechanochemical approaches using ball mills circumvent solvent use, their energy-intensive operations and limited scalability remain pressing challenges that need to be addressed in this field. Herein, we disclose a new solventless reaction where precisely engineered thermodynamic parameters autonomously drive Suzuki–Miyaura coupling between aryl halides and boronic acids at 50–150°C without additional solvent, ligand, diffusant mediation, or mechanical agitation. This spontaneous process demonstrates exceptional generality across electron-deficient and sterically hindered substrates, achieving 99% yields of biphenyl derivatives with near-perfect atom economy. Crucially, under the action of commercialized palladium carbon, there is no need for excessive alkali, enabling high conversion and excellent chemical selectivity within four hours through thermally activated solid/liquid state diffusion.