Science of Synthesis

Trauner, D., Science of Synthesis, (2008) 32, 533.

General Introduction

Enols are marked by a C=C bond bearing a hydroxy substituent, which renders them electron-rich, nucleophilic alkenes (‌Scheme 1‌). These compounds fall into two categories: (a) nonstabilized enols that are thermodynamically less stable than their corresponding “oxo” tautomers, and (b) enols that are stabilized by electronic effects or through intramolecular hydrogen bonds. Electronic effects include the formation of extended conjugated systems, highly substituted C=C bonds, or the avoidance of unfavorable dipolar interactions. Whereas the former category of enols is usually formed as a transient species and is more of theoretical interest, the latter can be isolated and has important applications in synthesis. The chemistry of enols has been comprehensively reviewed, and the structures of a variety of different enols are presented in ‌Scheme 1‌.[‌1‌]

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References

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• 8.Meeeee-Meee, (8888) 8/8e, 8.