Aquation

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Aquation is the chemical reaction involving "incorporation of one or more integral molecules of water" with or without displacement of other atoms or groups. [1] The term is typically employed to refer to reactions of metal complexes where an anion is displaced by water. For example, bromopentaamminecobalt(III) undergoes the following aquation reaction to give a metal aquo complex: [2]

[Co(NH3)5Br]2+ + H2O → [Co(NH3)5(H2O)]3+ + Br

This aquation reaction is catalyzed both by acid and by base. Acid catalysis involves protonation of the bromide, converting it to a better leaving group. Base hydrolysis proceeds by the SN1cB mechanism, which begins with deprotonation of an ammonia ligand.

See also

Hydration reaction

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References

  1. IUPAC , Compendium of Chemical Terminology , 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006) " aquation ". doi : 10.1351/goldbook.A00426
  2. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN   978-0-08-037941-8.