Superacid-catalyzed reactions of olefinic pyrazines: an example of anti-Markovnikov addition involving superelectrophiles.

@article{Zhang2005SuperacidcatalyzedRO,
  title={Superacid-catalyzed reactions of olefinic pyrazines: an example of anti-Markovnikov addition involving superelectrophiles.},
  author={Yiliang Zhang and Jason Briski and Yun Zhang and Rendy Rendy and Douglas A. Klumpp},
  journal={Organic letters},
  year={2005},
  volume={7 12},
  pages={
          2505-8
        }
}
[reaction: see text] Olefinic pyrazines are found to react with benzene in CF3SO3H and give anti-Markovnikov-type addition products. We propose that this is caused by two effects: destabilization of the carbocationic intermediates that would lead to Markovnikov-type products and the generation of a considerable amount of positive charge at the terminal carbon of the olefinic groups. This suggests that acid-catalyzed addition reactions can give anti-Markovnikov-type products when a multiply… 
14 Citations

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References

SHOWING 1-10 OF 20 REFERENCES

Dicationic electrophiles from olefinic amines in superacid.

A general mechanism is proposed that invokes the formation of reactive, dicationic electrophiles and the direct observation of a diprotonated species is reported from low-temperature NMR experiments.

Superacid-catalyzed reactions of cinnamic acids and the role of superelectrophiles.

It is provided clear evidence that protonated carboxylic acid groups (or the corresponding acyl cation) can enhance the reactivity of an adjacent electrophilic center.

Superacidic Trifluoromethanesulfonic Acid-Induced Cycli-Acyalkylation of Aromatics

Superacidic trifluoromethanesulfonic acid-induced synthesis of 1-indanone and 1-tetralone derivatives through Friedel-Crafts cycli-acyalkylation of aromatics with unsaturated carboxylic acids was

Dicationic intermediates involving protonated amides: dual modes of reactivity including the acylation of arenes.

In the Brønsted superacid CF( 3)SO(3)H (triflic acid), amides are able to form reactive, dicationic electrophiles that participate in two distinctly different types of electrophilic reactions.

Catalytic Markovnikov and anti-Markovnikov functionalization of alkenes and alkynes: recent developments and trends.

It is nowadays possible to control the regiochemistry of various additions of nucleophiles to alkenes and alkynes by applying different transition-metal catalysts.

Anodic dimerization of enamines, 2-cyano-2-phenylvinylamines.

The effects of substituents (R1, R2, and R3) on the electrochemical oxidation of the title enamines, R1-C6H4-C (CN)=CH-NR2R3 (1) were investigated in acetonitrile at a glassy carbon electrode

Study of Reactive Intermediates in Photoinduced Electron Transfer Anti-Markovnikov Addition of Methanol to 1-Phenylcycloalkenes

Irradiation of 1-phenylcycloalkenes (1) with cyanoaromatics as electron-accepting sensitizers in MeCN and PhH containing 1.0 M MeOH gave trans- (2) and cis-isomers (3) of anti-Markovnikov adducts. It

Ab Initio/IGLO/GIAO-MP2 Studies of Fluorocarbocations: Experimental and Theoretical Investigation of the Cleavage Reaction of Trifluoroacetic Acid in Superacids1a

The structures of a number of fluorocarbocations were calculated at the correlated MP2/6-31G* level. 13C and 19F NMR chemical shifts of fluorocarbocations were calculated for the first time using

Superacidic activation of 1- and 3-isoquinolinols and their electrophilic reactions.

Isomeric 1- and 3-isoquinolinols (11 and 12) when activated in CF(3)SO(3)H-SbF(5) acid system undergo selective ionic hydrogenation with cyclohexane to give 5,6,7,8-tetrahydro-1(2H)- and