Solventless Catalytic C-H and C-X Functionalization without Ball Milling.

A low-cost, operationally simple approach to eight different solventless Rh-, Ru-, Ir-, and Pd-catalyzed C-H and C-X functionalizations, as well as the synthesis of difficult-to-make rhodacyclic complexes, is presented. The method uses open-air grinding and heating, is reproducible, gives competitive yields compared with automated ball milling protocols, and can be extended to the late-stage modification of various bioactive compounds.