12.9.3: Electrophilic Substitutions
- Page ID
- 385561
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We have seen how metal ion binding can alter the pKa of a bound ligand by polarizing bonds. In a similar fashion, binding of a ligand to a metal ion can alter the location of electron density so that positions on the ligand take on new reactivity. This can be seen in the case of acetylacetone (acac) complexes (most recently discussed in section 12.5.3). The metal coordination to the acac ligand induces enol tautomerization, placing electron density at the central alpha carbon and causing it to become a potent nucleophile. Reactions occur at that nucleophilic carbon in similar manner to the electrophilic aromatic substitution reactions that you may have learned about in an Organic Chemistry course.
