472ENOLS AND ENOLATES18.6(b)Enolization of the central methylene group can involve either of the two carbonyl groups.18.7(b)Removal of a proton from 1-phenyl-1,3-butanedione occurs on the methylene group betweenthe carbonyls.The three most stable resonance forms of this anion are(c)Deprotonation at C-2 of this b-dicarbonyl compound yields the carbanion shown.The three most stable resonance forms of the anion are:18.8Each of the fve ahydrogens has been replaced by deuterium by base-catalyzed enolization. Onlythe OCH3hydrogens and the hydrogens on the aromatic ring are observed in the 1H NMR spectrumat d3.9 ppm and d6.7–6.9 ppm, respectively.18.9a-Chlorination of (R)-sec-butyl phenyl ketone in acetic acid proceeds via the enol. The enol is achi-ral and yields equal amounts of (
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This note was uploaded on 09/28/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.