[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/en\/wiki2\/radical-nucleophilic-aromatic-substitution-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/en\/wiki2\/radical-nucleophilic-aromatic-substitution-wikipedia\/","headline":"Radical-nucleophilic aromatic substitution – Wikipedia","name":"Radical-nucleophilic aromatic substitution – Wikipedia","description":"before-content-x4 From Wikipedia, the free encyclopedia after-content-x4 Radical-nucleophilic aromatic substitution or SRN1 in organic chemistry is a type of substitution","datePublished":"2016-03-03","dateModified":"2016-03-03","author":{"@type":"Person","@id":"https:\/\/wiki.edu.vn\/en\/wiki2\/author\/lordneo\/#Person","name":"lordneo","url":"https:\/\/wiki.edu.vn\/en\/wiki2\/author\/lordneo\/","image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","height":96,"width":96}},"publisher":{"@type":"Organization","name":"Enzyklop\u00e4die","logo":{"@type":"ImageObject","@id":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","url":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","width":600,"height":60}},"image":{"@type":"ImageObject","@id":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/a\/a4\/Radical-nucleophilic_aromatic_substitution_overview.png\/300px-Radical-nucleophilic_aromatic_substitution_overview.png","url":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/a\/a4\/Radical-nucleophilic_aromatic_substitution_overview.png\/300px-Radical-nucleophilic_aromatic_substitution_overview.png","height":"84","width":"300"},"url":"https:\/\/wiki.edu.vn\/en\/wiki2\/radical-nucleophilic-aromatic-substitution-wikipedia\/","wordCount":1931,"articleBody":"     (adsbygoogle = window.adsbygoogle || []).push({});before-content-x4From Wikipedia, the free encyclopedia       (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4Radical-nucleophilic aromatic substitution or SRN1 in organic chemistry is a type of substitution reaction in which a certain substituent on an aromatic compound is replaced by a nucleophile through an intermediary free radical species:The substituent X is a halide and nucleophiles can be sodium amide, an alkoxide or a carbon nucleophile such as an enolate.[1] In contrast to regular nucleophilic aromatic substitution, deactivating groups on the arene are not required.[2]       (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4This reaction type was discovered in 1970 by Bunnett and Kim[3] and the abbreviation SRN1 stands for substitution radical-nucleophilic unimolecular as it shares properties with an aliphatic SN1 reaction. An example of this reaction type is the Sandmeyer reaction.Reaction mechanism[edit]In this radical substitution the aryl halide 1 accepts an electron from a radical initiator forming a radical anion 2. This intermediate collapses into an aryl radical 3 and a halide anion. The aryl radical reacts with the nucleophile 4 to a new radical anion 5 which goes on to form the substituted product by transferring its electron to new aryl halide in the chain propagation. Alternatively the phenyl radical can abstract any loose proton from 7 forming the arene 8 in a chain termination reaction.The involvement of a radical intermediate in a new type of nucleophilic aromatic substitution was invoked when the product distribution was compared between a certain aromatic chloride and an aromatic iodide in reaction with potassium amide. The chloride reaction proceeds through a classical aryne intermediate:The isomers 1a and 1b form the same aryne 2 which continues to react to the anilines 3a and 3b in a 1 to 1.5 ratio. Clear-cut cine-substitution would give a 1:1 ratio, but additional steric and electronic factors come into play as well.       (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4Replacing chlorine by iodine in the 1,2,4-trimethylbenzene moiety drastically changes the product distribution:It now resembles ipso-substitution with 1a forming preferentially 3a and 1b forming 3b. Radical scavengers suppress ipso-substitution in favor of cine-substitution and the addition of potassium metal as an electron donor and radical initiator does exactly the opposite.[4]See also[edit]References[edit]^ Phenomenon of radical anion fragmentation in the course of aromatic SRN reactions Roberto A. Rossi Acc. Chem. Res.; 1982; 15(6) pp 164 \u2013 170;doi:10.1021\/ar00078a001.^ Rossi, R. A.; Pierini, A. B.; Santiago, A. N. Org. React. 1999, 54, 1. doi:10.1002\/0471264180.or054.01^ Evidence for a radical mechanism of aromatic “nucleophilic” substitution Joseph F. Bunnett and Jhong Kook Kim J. Am. Chem. Soc.; 1970; 92(25) pp 7463 \u2013 7464. (doi:10.1021\/ja00728a037)^ Alkali metal promoted aromatic “nucleophilic” substitution Joseph F. Bunnett and Jhong Kook Kim J. Am. Chem. Soc. 1970, 92, 7464 \u2013 7466. (doi:10.1021\/ja00728a038)li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:\" \"counter(listitem)\"a0 \"}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:\" (\"counter(listitem)\"a0 \"}]]>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}]]>     (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4"},{"@context":"http:\/\/schema.org\/","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki2\/#breadcrumbitem","name":"Enzyklop\u00e4die"}},{"@type":"ListItem","position":2,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki2\/radical-nucleophilic-aromatic-substitution-wikipedia\/#breadcrumbitem","name":"Radical-nucleophilic aromatic substitution – Wikipedia"}}]}]