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  2. Benzene - Wikipedia

    en.wikipedia.org/wiki/Benzene

    Benzene is sufficiently nucleophilic that it undergoes substitution by acylium ions and alkyl carbocations to give substituted derivatives. Electrophilic aromatic substitution of benzene. The most widely practiced example of this reaction is the ethylation of benzene. Approximately 24,700,000 tons were produced in 1999. [73]

  3. Free-radical addition - Wikipedia

    en.wikipedia.org/wiki/Free-radical_addition

    Radical reactions with arenes typically present retrosynthetically as instances of nucleophilic aromatic substitution, [citation needed] because generating the aryl radical requires a strong (radical) leaving group. [3]: 686–687 One example is the Meerwein arylation.

  4. Nucleophilic aromatic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_aromatic...

    Aromatic nucleophilic substitution. This reaction differs from a common S N 2 reaction, because it happens at a trigonal carbon atom (sp 2 hybridization). The mechanism of S N 2 reaction does not occur due to steric hindrance of the benzene ring. In order to attack the C atom, the nucleophile must approach in line with the C-LG (leaving group ...

  5. Dow process (phenol) - Wikipedia

    en.wikipedia.org/wiki/Dow_process_(phenol)

    Benzene can be easily converted to chlorobenzene by nucleophilic aromatic substitution via a benzyne intermediate. [1] It is treated with aqueous sodium hydroxide at 350 °C and 300 bar or molten sodium hydroxide at 350 °C to convert it to sodium phenoxide , which yields phenol upon acidification. [ 2 ]

  6. Substitution reaction - Wikipedia

    en.wikipedia.org/wiki/Substitution_reaction

    Examples of associative mechanisms are commonly found in the chemistry of 16e square planar metal complexes, e.g. Vaska's complex and tetrachloroplatinate. The rate law is governed by the Eigen–Wilkins Mechanism. Dissociative substitution resembles the S N 1 mechanism in organic chemistry.

  7. Ortho effect - Wikipedia

    en.wikipedia.org/wiki/Ortho_effect

    There are three main ortho effects in substituted benzene compounds: Steric hindrance forces cause substitution of a chemical group in the ortho position of benzoic acids become stronger acids. Steric inhibition of protonation caused by substitution of anilines to become weaker bases, compared to substitution of isomers in the meta and para ...

  8. Alkyne trimerisation - Wikipedia

    en.wikipedia.org/wiki/Alkyne_trimerisation

    An alkyne trimerisation is a [2+2+2] cycloaddition reaction in which three alkyne units (C≡C) react to form a benzene ring. The reaction requires a metal catalyst. The process is of historic interest as well as being applicable to organic synthesis. [1] Being a cycloaddition reaction, it has high atom economy.

  9. SN1 reaction - Wikipedia

    en.wikipedia.org/wiki/SN1_reaction

    An example of a reaction proceeding in a S N 1 fashion is the synthesis of 2,5-dichloro-2,5-dimethylhexane from the corresponding diol with concentrated hydrochloric acid: [8] As the alpha and beta substitutions increase with respect to leaving groups, the reaction is diverted from S N 2 to S N 1.