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Electrophilic substitutions cyanation reactions

In this equation, E normally corresponds to hydrogen but can also be another group, e.g. -OCH3. The denotation E is used to show the interplay between nucleophiles and electrophiles in electroorganic reactions. Thus, due to the oxidative nature of the process, a nucleophile can be used as a reagent in an otherwise impossible substitution reaction. As an example of an anodic substitution process, electrochemical cyanation of an aromatic hydrocarbon can be mentioned ... [Pg.10]

Within the year a wide range of photoreactions in which an aromatic residue undergoes change in substitution has been published. As previously, the diversity of the various processes makes any classification of the reactions unrealistic, and so their order of presentation here is somewhat arbitrary. Aromatic photosubstitution reactions have been reviewed by Parkanyi although the treatment is not extensive, the processes of free radical, electrophilic, and nucleophilic photoinduced substitutions of arenes are well covered.Arene photoreactions initiated by electron transfer with electron donors or acceptors are the subject of a review by Pac and Sakurai. The requirements for the efficient photogeneration of the ion radicals are considered and the synthetic utility of the photoreactions, which include reduction, cyanation, and amination, is discussed. [Pg.323]

Substituted 2-oxazolidones 165 are useful chiral auxiliaries for diastereoselective functionalization at the a-carbon of their amide carbonyl group. The a-fluoroaldehydes 166 were prepared by a series of reactions electrophilic fluorination of the corresponding oxazolidinone sodium enolates with AMluorobenzenesulfonimine reductive removal of the auxiliary with LiBH4 and Dess-Martin oxidation. The aldehydes are so unstable for isolation that they are converted with (R)-/ -toluenesulfinamide to /7-toluenesul(inimines 167, which are isol-able and satisfactorily enantio-enriched. Chiral sulfinimine-mediated diastereoselective Strecker cyanation with aluminum cyanide provided cyanides 168 in excellent diastereose-lectivity, which were finally derived to 3-fluoroamino acids 169 (see Scheme 9.37) [63]. [Pg.234]


See other pages where Electrophilic substitutions cyanation reactions is mentioned: [Pg.326]    [Pg.280]    [Pg.564]    [Pg.251]    [Pg.41]    [Pg.264]    [Pg.83]    [Pg.175]    [Pg.83]    [Pg.83]    [Pg.5]    [Pg.72]    [Pg.83]    [Pg.12]    [Pg.310]    [Pg.103]    [Pg.306]    [Pg.223]   
See also in sourсe #XX -- [ Pg.275 , Pg.276 , Pg.277 ]




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Cyanate

Cyanate reactions

Cyanates

Cyanates reactions

Cyanation

Cyanations

Cyanations electrophilic

Electrophilic cyanation

Electrophilic substitution reaction

Reactions cyanation

Substitution reactions electrophile

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