Conventional organic synthesis generally relies on the use of liquid organic solvents to dissolve the reactants. Therefore, reactions of sparingly soluble or insoluble substrates are challenging and often ineffective. The development of a solventindependent solid-state approach that overcomes this longstanding solubility issue would provide innovative synthetic solutions and access to new areas of chemical space. Here, we report extremely fast and highly efficient solid-state palladium-catalyzed Suzuki− Miyaura cross-coupling reactions via a high-temperature ball-milling technique. This solid-state protocol enables the highly efficient cross-couplings of insoluble aryl halides with large polyaromatic structures that are barely reactive under conventional solution-based conditions. Notably, we discovered a new luminescent organic material with a strong red emission. This material was prepared via the solid-state coupling of Pigment violet 23, a compound that has so far not been involved in molecular transformations due to its extremely low solubility. This study thus provides a practical method for accessing unexplored areas of chemical space through molecular transformations of insoluble organic compounds that cannot be carried out by any other approach.

Herein, we report a novel strategy for introducing a luminophore into generic polymers facilitated by mechanical stimulation. In this study, polymeric mechanoradicals were formed in situ under ball‐milling conditions to undergo radical–radical coupling with a prefluorescent nitroxide‐based reagent in order to incorporate a luminophore into the polymer main chains via a covalent bond. This method allowed the direct and conceptually simple preparation of luminescent polymeric materials from a wide range of generic polymers such as polystyrene, polymethyl methacrylate, and polyethylene. These results indicate that the present mechanoradical coupling strategy may help to transform existing commodity polymers into more valuable functional materials.

Herein, we report a novel strategy for introducing a luminophore into generic polymers facilitated by mechanical stimulation. In this study, polymeric mechanoradicals were formed in situ under ball‐milling conditions to undergo radical–radical coupling with a prefluorescent nitroxide‐based reagent in order to incorporate a luminophore into the polymer main chains via a covalent bond. This method allowed the direct and conceptually simple preparation of luminescent polymeric materials from a wide range of generic polymers such as polystyrene, polymethyl methacrylate, and polyethylene. These results indicate that the present mechanoradical coupling strategy may help to transform existing commodity polymers into more valuable functional materials.

Mixed crystals composed of two distinct gold isocyanide complexes are reported.

A nitroxide‐based prefluorescent radical undergoes radical—radical coupling with in situ formed polymeric mechanoradicals under ball‐milling conditions to incorporate the coumarin‐based luminophore into generic polymers, as represented in the picture. By using this method, Koji Kubota, Mingoo Jin, Hajime Ito et al. prepared luminescent polymeric materials from a wide range of generic polymers without sophisticated chemical synthesis in their Research Article on page 16003.