Catalysts achieve chemoselectivity through various mechanisms, including:
1. Steric Effects: The spatial arrangement of atoms in the catalyst and substrate can influence which functional group is more accessible for the reaction. 2. Electronic Effects: The distribution of electron density within the catalyst and substrate can make certain functional groups more reactive. 3. Ligand Design: Customizing the ligands in transition metal catalysts can help in directing the reactivity towards specific functional groups. 4. Substrate-Catalyst Interaction: Specific interactions, such as hydrogen bonding or Ï-Ï stacking, between the catalyst and substrate can enhance selectivity.
