Chemoselectivity is the preferential reaction of a chemical reagent with one of two or more different functional groups.[1]

This phenomenon is often influenced by the molecular connectivity alone, and may involve the use of protecting groups in more complex reactions. While predictions based on connectivity are generally deemed plausible, the physical outcome of a reaction depends on numerous factors that are typically challenging to predict with high precision (such as solvent effects, atomic orbital interactions, etc.).[2]

Predicting chemoselectivity can be a complex task; however, it is not uncommon to observe selective outcomes in cases where numerous reactions are feasible. Examples include the greater relative chemoselectivity of sodium borohydride versus lithium aluminium hydride for the organic reduction of 4-nitro-2-chlorobenzonitrile to the corresponding aniline, 4-amino-2-chlorobenzonitrile. In another example, the compound 4-methoxyacetophenone is oxidized by bleach at the ketone group at high pH (forming the carboxylic acid) and oxidized by EAS (to the aryl chloride) at low pH.[3]

See also

References

  1. ^ "Chemoselectivity (chemoselective)". IUPAC Compendium of Chemical Terminology (3rd ed.). International Union of Pure and Applied Chemistry. 2006. doi:10.1351/goldbook.C01051 – via Online version 3.0.1, 2019.
  2. ^ Shenvi RA, O'Malley DP, Baran PS (April 2009). "Chemoselectivity: the mother of invention in total synthesis". Accounts of Chemical Research. 42 (4): 530–541. doi:10.1021/ar800182r. PMC 2765532. PMID 19182997.
  3. ^ Ballard CE (2010). "pH-Controlled Oxidation of an Aromatic Ketone: Structural Elucidation of the Products of Two Green Chemical Reactions". Journal of Chemical Education. 87 (2): 190–193. Bibcode:2010JChEd..87..190B. doi:10.1021/ed800054s.
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