The developed mechanochemical procedure significantly surpassed mixHC [8] synthesis in solution, yielding superior selectivity and conversion rates (see S35-S38). Solution-state processes are affected by diffusion with diffusion constants varying for monomers, aggregates, and oligomeric intermediates due to size difference. In mechanochemistry, reaction rates do not directly depend on the molecular size of the intermediates, but rather on the number of molecular collisions. In addition to the chemical advantages, solventfree synthesis produces less waste (PMI = 4) compared to reaction in solution (PMI = 306), and is more sustainable based on the respective green metrics (see S35-S38). 32