Elimination Reactions of Alcohols, Enols, and Phenols

ELIMINATION REACTIONS OF ALCOHOLS, ENOLS, AND PHENOLS I. Introduction 

under general laboratory conditions, elimination of the hydroxide anion (OH ), hydroxyl radical ( OH), or the hydroxyl cation (OH ) from an alcohol, enol, or phenol, leaving behind a carbocation, carbon radical, or carbanion, respectively, appears to be unknown. Indeed, even the loss of water, with the OH and H coming from adjacent atoms and, in this way, introducing unsaturation (or further unsaturation) into a compound in the laboratory and without involvement of an acid, base, or acidic, basic, or neutral metal catalyst is rare. 

Alcohols and derivatives of alcohols (e.g., esters) undergo both catalzyed and thermal elimination of the elements of water to form alkenes (Equation 8.38). 

In some cases, ethers are also formed (Equation 8.39) and elimination of water in that reaction may precede carbon-oxygen (ether) bond formation. 

Although direct elimination of water from phenols and enols is unknown, those compounds and some of their derivatives do formally lose water in the sense that an addition-elimination reaction series can replace the hydroxyl unit (see Chapter 7, Part 5b). 

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Part I. The Reactions of Alcohols, Enols, and Phenols Oxidation, Reduction, Substitution, Addition, Elimination, and Rearrangement Part II. Ethers... 

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