[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/organizer-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/organizer-wikipedia\/","headline":"Organizer \u2014 Wikipedia","name":"Organizer \u2014 Wikipedia","description":"before-content-x4 A wikipedia article, free l’encyclop\u00e9i. after-content-x4 And organozincique is an organometallic compound containing a carbon – zinc link [","datePublished":"2019-11-27","dateModified":"2019-11-27","author":{"@type":"Person","@id":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/author\/lordneo\/#Person","name":"lordneo","url":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/author\/lordneo\/","image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/44a4cee54c4c053e967fe3e7d054edd4?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/44a4cee54c4c053e967fe3e7d054edd4?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\/e\/eb\/OrganozincLogo.png\/110px-OrganozincLogo.png","url":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/e\/eb\/OrganozincLogo.png\/110px-OrganozincLogo.png","height":"39","width":"110"},"url":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/organizer-wikipedia\/","wordCount":5340,"articleBody":"     (adsbygoogle = window.adsbygoogle || []).push({});before-content-x4A wikipedia article, free l’encyclop\u00e9i.          (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4And organozincique is an organometallic compound containing a carbon – zinc link [ first ] . These are reactive compounds that are sensitive to air and water. They are involved in various important chemical reactions such as the Reformski reaction and the coupling of Negishi. The organozincics were among the first organomotallic compounds known with an \u03c3 bond between a carbon atom and a metal atom. They are less reactive than similar organomietallic, such as organomagnesians and Grignard reagents. Di\u00e9thylzinc zn (ch 2 CH 3 ) 2  fut le premier organozincique synth\u00e9tis\u00e9, en 1848 par le chimiste britannique Edward Frankland, en chauffant de l’iodo\u00e9thane CH3CH2I en pr\u00e9sence de zinc \u00e9l\u00e9mentaire[2]\u00a0: la r\u00e9action produisit un liquide incolore volatil qui s’enflamma spontan\u00e9ment au contact de l’air\u00a0; auparavant, on ne connaissait que des complexes organiques de l’arsenic et du sel de Zeise ayant des ligands organiques sur un atome m\u00e9tallique.       (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4Due to their pyrophic nature, organozincics are generally prepared for air. They are unstable in the pro -solvents. They are mostly prepared on-site To be immediately used without being isolated specifically, but some were isolated as pure substances and were characterized in detail [ 3 ] . Among the organozincics, we can distinguish the following categories according to the number of Zn – C connections [ 4 ] : Diorganozincics r 2 Zn , dans lesquels deux ligands alkyle sont li\u00e9s \u00e0 l’atome de zinc\u00a0;The heteroleptics, in which an electronegative or monoanionic ligand, for example an X halogenure, is linked to the zinc atom, itself linked to an alkyl or aryl ligand; Ionic organozincics, which include organozincates R n Zn \u2212and organozincic cations RZnL n +, where he is a ligand.  In its complexes, zinc ( II ) Adopt several geometries, generally Octa\u00e9drique, Tetrahedral, as well as several Pentacorian geometries. This structural flexibility can be attributed to the electronic zinc configuration, which can be written [AR] 3D ten 4s 2 . The 3D orbital is complete, so that there is no ligand field effect. Coordination geometry is therefore largely determined by electrostatic and steric interactions [ 4 ] . The organozincics are generally bi- or knitted, which reflects the fact that the carbanions are strongly electron donors.        (adsbygoogle = window.adsbygoogle || []).push({});after-content-x4Diorganozincic complexes are typically in form R 2 Zn . Les compos\u00e9s de type dialkylzinc sont monom\u00e9riques avec une coordination lin\u00e9aire sur l’atome de zinc[5]. La liaison covalente entre les atomes de carbone et de zinc est polaris\u00e9e vers l’atome de carbone en raison de la diff\u00e9rence d’\u00e9lectron\u00e9gativit\u00e9 entre les deux (2,55 pour le carbone contre 1,65 pour le zinc sur l’\u00e9chelle de Pauling). Le moment dipolaire des r\u00e9actifs diorganozinciques sym\u00e9triques peut \u00eatre consid\u00e9r\u00e9 comme nul dans ces complexes lin\u00e9aires, ce qui explique leur solubilit\u00e9 dans les solvants apolaires comme le cyclohexane. Contrairement \u00e0 d’autres alkyles binaires m\u00e9talliques, les esp\u00e8ces diorganozinciques ont une faible affinit\u00e9 pour la complexation avec les solvants de type \u00e9ther. Les liaisons dans les compos\u00e9s R2Zn sont d\u00e9crites comme mettant en \u0153uvre des hybridations sp sur l’atome de zinc[4].The zinc atom therefore has two binding orbitals and three non -binding orbitals available to establish links. In the absence of electrons donor ligands, the zinc atom cannot complete its orbitals, so that it binds to a relatively small number of alkyl and Aryle groups. The binding of a halogen to the zinc atom accentuates the donor and acceptor of these orbitals, which allows the formation of clusters , for example by involving ligands pontants [ 4 ] . There are several methods for obtaining organozincics. Diorganozinc type compounds available are the dimethylzinc zn (CH 3 ) 2 , le di\u00e9thylzinc Zn(CH2CH3)2 et le diph\u00e9nylzinc Zn(C6H5)2. Ce sont des r\u00e9actifs chers et difficiles \u00e0 manipuler. Il est \u00e9galement possible de produire ses organozinciques in situ \u00e0 partir de pr\u00e9curseurs organobrom\u00e9s qui sont meilleur march\u00e9[6]\u00a0:In the example above, the Bromobenzene C 6 H 5 Br  est converti en ph\u00e9nyllithium C6H5Li par r\u00e9action avec quatre \u00e9quivalents de n-butyllithium CH3CH2CH2CH2Li. Une transm\u00e9tallation avec le chlorure de zinc ZnCl2 donne ensuite le diph\u00e9nylzinc Zn(C6H5)2.From elementary zinc [ modifier | Modifier and code ] The Diethylzinc Zn (CH 2 CH 3 ) 2  par Edward Frankland mettait en \u0153uvre de l’iodo\u00e9thane CH3CH2I avec du zinc. Ce dernier doit \u00eatre activ\u00e9 pour faciliter la r\u00e9action d’oxydor\u00e9duction. L’une des formes activ\u00e9es du zinc utilis\u00e9es par Frankland \u00e9tait le couple zinc-cuivre[2]\u00a0:2 CH 3 CH 2 I  + 2 Zn0 \u27f6 Zn(CH2CH3)2 + ZnI2.Zinc can also be activated in the form of rieke metal by reducing zinc chloride ZNCL 2  avec du potassium. Cette forme s’est r\u00e9v\u00e9l\u00e9e utile pour des r\u00e9actions telles que le couplage de Negishi et le couplage de Fukuyama. La formations de r\u00e9actifs organozinciques est facilit\u00e9e lorsque les halog\u00e9noalcanes ou les halog\u00e9nures d’aryle portent des substituants attirant les \u00e9lectrons, comme les nitriles et les esters[7],[8]."},{"@context":"http:\/\/schema.org\/","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/#breadcrumbitem","name":"Enzyklop\u00e4die"}},{"@type":"ListItem","position":2,"item":{"@id":"https:\/\/wiki.edu.vn\/all2en\/wiki32\/organizer-wikipedia\/#breadcrumbitem","name":"Organizer \u2014 Wikipedia"}}]}]