Enolate Ions and Enols Halogenation Reactions Alkylation Reactions Condensation Reactions Enolate Ions from -Dicarbonyl Compounds Other Reactions of Enolate Ions and Enols
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چکیده
18.1 Enolate Ions and Enols We described in Chapters 13 and 16 that the C=O group of carbonyl compounds is reactive to attack by both nucleophiles (N:) and electrophiles (E+). We also saw in Chapter 13 that the C=O group causes Hs attached to its α-C (H-Cα-C=O) to be unusually acidic. As a result, these α-CH's are removed by bases giving enolate ions (-:Cα-C=O) Figure 18.01) that can react as nucleophiles with different electrophiles (E+) to form compounds with the general structure E-CαC=O. Figure 18.01
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Carbonyl Compounds Enols and Enolate Ons. Unsaturated and Polycarbonyl Compounds
ome of the most useful reactions of carbonyl compounds involve carbonhydrogen bonds adjacent to the carbonyl group. Such reactions, which can be regarded as the backbone of much synthetic organic chemistry, usually result in the replacement of the hydrogen by some other atom or group, as in the I I I I sequence H-C-C=O -+ X-C-C=O. The important examples we I I will consider in this chapter are ...
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