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Migratory Aptitude
Migratory aptitude is the relative ability of a migrating group to migrate in a rearrangement reaction. Migratory aptitudes vary in different reactions, depending on multiple factors. In the Baeyer-Villiger reaction, the more substituted group, in general, migrates. In the pinacol rearrangement The pinacol–pinacolone rearrangement is a method for converting a 1,2-diol to a carbonyl compound in organic chemistry. The 1,2-rearrangement takes place under acidic conditions. The name of the rearrangement reaction comes from the rearrangemen ..., the order of migratory aptitude has not been determined unambiguously, but some trends have been determined. For example, relative migratory aptitudes for alkyl substituents is Hydride >Phenide>C(CH3)3> C2H5 > CH3. References Organic chemistry {{organic-chem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rearrangement Reaction
In organic chemistry, a rearrangement reaction is a broad class of organic reactions where the carbon skeleton of a molecule is rearranged to give a structural isomer of the original molecule. Often a substituent moves from one atom to another atom in the same molecule, hence these reactions are usually intramolecular. In the example below, the substituent R moves from carbon atom 1 to carbon atom 2: :\underset\ce\ce\underset\ce\ce Intermolecular rearrangements also take place. A rearrangement is not well represented by simple and discrete electron transfers (represented by curved arrows in organic chemistry texts). The actual mechanism of alkyl groups moving, as in Wagner-Meerwein rearrangement, probably involves transfer of the moving alkyl group fluidly along a bond, not ionic bond-breaking and forming. In pericyclic reactions, explanation by orbital interactions give a better picture than simple discrete electron transfers. It is, nevertheless, possible to draw the curv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compendium Of Chemical Terminology
The International Union of Pure and Applied Chemistry publishes many books which contain its complete list of definitions. The definitions are divided into seven "colour books": Gold, Green, Blue, Purple, Orange, White, and Red. There is also an eighth book—the "Silver Book". The eight ''colour books'' ''Blue Book'' ''Nomenclature of Organic Chemistry'', commonly referred to by chemists as the ''Blue Book'', is a collection of recommendations on organic chemical nomenclature published at irregular intervals by the International Union of Pure and Applied Chemistry (IUPAC). A full edition was published in 1979, an abridged and updated version of which was published in 1993 as ''A Guide to IUPAC Nomenclature of Organic Compounds''. Both of these are now out-of-print in their paper versions, but are available free of charge in electronic versions. After the release of a draft version for public comment in 2004 and the publication of several revised sections in the journal '' Pur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union Of Pure And Applied Chemistry
The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is a member of the International Science Council (ISC). IUPAC is registered in Zürich, Switzerland, and the administrative office, known as the "IUPAC Secretariat", is in Research Triangle Park, North Carolina, United States. This administrative office is headed by IUPAC's executive director, currently Lynn Soby. IUPAC was established in 1919 as the successor of the International Congress of Applied Chemistry for the advancement of chemistry. Its members, the National Adhering Organizations, can be national chemistry societies, national academies of sciences, or other bodies representing chemists. There are fifty-four National Adhering Organizations and three Associate National Adhering Organizations. IUPAC's Inter-divisional Committee on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinacol Rearrangement
The pinacol–pinacolone rearrangement is a method for converting a 1,2-diol to a carbonyl compound in organic chemistry. The 1,2-rearrangement takes place under acidic conditions. The name of the rearrangement reaction comes from the rearrangement of pinacol to pinacolone. : This reaction was first described by Wilhelm Rudolph Fittig in 1860 of the famed Fittig reaction involving coupling of 2 aryl halides in presence of sodium metal in dry ethereal solution. Mechanism In the course of this organic reaction, protonation of one of the –OH groups occurs and a carbocation is formed. If the –OH groups are not alike (i.e. the pinacol is asymmetrical), then the one which creates a more stable carbocation participates in the reaction. Subsequently, an alkyl group from the adjacent carbon migrates to the carbocation center. The driving force for this rearrangement step is believed to be the relative stability of the resultant oxonium ion. Although the initial carbocation is already ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
