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Organic Reactions
Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions, substitution reactions, pericyclic reactions, rearrangement reactions, photochemical reactions and redox reactions. In organic synthesis, organic reactions are used in the construction of new organic molecules. The production of many man-made chemicals such as drugs, plastics, food additives, fabrics depend on organic reactions. The oldest organic reactions are combustion of organic fuels and saponification of fats to make soap. Modern organic chemistry starts with the Wöhler synthesis in 1828. In the history of the Nobel Prize in Chemistry awards have been given for the invention of specific organic reactions such as the Grignard reaction in 1912, the Diels–Alder reaction in 1950, the Wittig reaction in 1979 and olefin metathesis in 2005. Classifications Organic chemistry has a strong tradition of naming a specif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the chemistry, chemical transformation of one set of chemical substances to another. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an Gibbs free energy, energy change as new products are generated. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize In Chemistry
The Nobel Prize in Chemistry () is awarded annually by the Royal Swedish Academy of Sciences to scientists in the various fields of chemistry. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895, awarded for outstanding contributions in chemistry, physics, literature, peace, and physiology or medicine. This award is administered by the Nobel Foundation and awarded by the Royal Swedish Academy of Sciences on proposal of the Nobel Committee for Chemistry, which consists of five members elected by the Academy. The award is presented in Stockholm at an annual ceremony on December 10th, the anniversary of Nobel's death. The first Nobel Prize in Chemistry was awarded in 1901 to Jacobus Henricus van 't Hoff, of the Netherlands, "for his discovery of the laws of chemical dynamics and osmotic pressure in solutions". From 1901 to 2024, the award has been bestowed on a total of 195 individuals. The 2024 Nobel Prize in Chemistry was awarded to Demis Hassabis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldol Reaction
The aldol reaction (aldol addition) is a Chemical reaction, reaction in organic chemistry that combines two Carbonyl group, carbonyl compounds (e.g. aldehydes or ketones) to form a new β-hydroxy carbonyl compound. Its simplest form might involve the nucleophilic addition of an Enolate, enolized ketone to another: These products are known as ''aldols'', from the ''ald''ehyde + alcoh''ol'', a structural motif seen in many of the products. The use of aldehyde in the name comes from its history: aldehydes are more reactive than ketones, so that the reaction was discovered first with them. The aldol reaction is paradigmatic in organic chemistry and one of the most common means of forming carbon–carbon bonds in organic chemistry. It lends its name to the family of aldol reactions and similar techniques analyze a whole family of carbonyl α-substitution reactions, as well as the Claisen condensation, diketone condensations. Scope Aldol structural units are found in many importa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ene Reaction
In organic chemistry, the ene reaction (also known as the Alder-ene reaction by its discoverer Kurt Alder in 1943) is a chemical reaction between an alkene with an allylic hydrogen (the ene) and a compound containing a multiple bond (the enophile), in order to form a new σ-bond with migration of the ene double bond and 1,5 hydrogen shift. The product is a substituted alkene with the double bond shifted to the allylic position. This transformation is a group transfer pericyclic reaction, and therefore, usually requires highly activated substrates and/or high temperatures. Nonetheless, the reaction is compatible with a wide variety of functional groups that can be appended to the ene and enophile moieties. Many useful Lewis acid-catalyzed ene reactions have been also developed, which can afford high yields and selectivities at significantly lower temperatures. Ene component Enes are π-bonded molecules that contain at least one hydrogen atom at the allylic, propargylic, or Π... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CBS Reduction
CBS Broadcasting Inc., commonly shortened to CBS (an abbreviation of its original name, Columbia Broadcasting System), is an American commercial broadcast television and radio network serving as the flagship property of the CBS Entertainment Group division of Paramount Global and is one of the company's three flagship subsidiaries, along with namesake Paramount Pictures and MTV. Founded in 1927, headquartered at the CBS Building in New York City and being part of the " Big Three" television networks, CBS has major production facilities and operations at the CBS Broadcast Center and the headquarters of owner Paramount at One Astor Plaza (both also in that city) and Television City and the CBS Studio Center in Los Angeles. It is sometimes referred to as the Eye Network, after the company's trademark symbol of an eye (which has been in use since October 20, 1951), and also the Tiffany Network, which alludes to the perceived high quality of its programming during the tenure of W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bingel Reaction
The Bingel reaction in fullerene chemistry is a fullerene cyclopropane, cyclopropanation reaction to a methanofullerene first discovered by C. Bingel in 1993 with the bromine, bromo derivative of diethyl malonate in the presence of a base (chemistry), base such as sodium hydride or DBU (chemistry), DBU. The preferred double bonds for this reaction on the fullerene surface are the shorter bonds at the junctions of two hexagons (6-6 bonds) and the driving force is relief of steric strain. The reaction is of importance in the field of chemistry because it allows the introduction of useful extensions to the fullerene sphere. These extensions alter their properties, for instance solubility and electrochemical behavior, and therefore widen the range of potential technical applications. Reaction mechanism The reaction mechanism for this reaction is as follows: a base (chemistry), base abstracts the acidic malonate proton generating a carbanion or enolate which reacts with the electron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claisen Rearrangement
The Claisen rearrangement is a powerful carbon–carbon chemical bond, bond-forming chemical reaction discovered by Rainer Ludwig Claisen. The heating of an allyl Vinyl group, vinyl ether will initiate a Sigmatropic reaction, [3,3]-sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl, driven by exergonically favored carbonyl CO bond formation with Δ(Δf''H'') ca. . Mechanism The Claisen rearrangement is an exothermic, concerted (bond cleavage and recombination) pericyclic reaction. Woodward–Hoffmann rules show a suprafacial, stereospecific reaction pathway. The kinetics are of the first order and the whole transformation proceeds through a highly ordered cyclic transition state and is intramolecular. Crossover experiment (chemistry), Crossover experiments eliminate the possibility of the rearrangement occurring via an intermolecular reaction mechanism and are consistent with an intramolecular process. There are substantial solvent effects observed in the Claisen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Named Reaction
A name reaction (or named reaction) is a chemical reaction named after its discoverer(s) or developer(s). Among the tens of thousands of organic reactions that are known, hundreds of such reactions are typically identified by the eponym. Well-known examples include the Grignard reaction, the Sabatier reaction, the Wittig reaction, the Claisen condensation, the Friedel–Crafts acylation, and the Diels–Alder reaction. Books have been published devoted exclusively to name reactions;Alfred Hassner, C. Stumer. ''Organic syntheses based on name reactions''. Elsevier, 2002. Li, Jie Jack. ''Name Reactions: A Collection of Detailed Reaction Mechanisms''. Springer, 2003. the ''Merck Index'', a chemical encyclopedia, also includes an appendix on name reactions. As organic chemistry developed during the 20th century, chemists started associating synthetically useful reactions with the names of their discoverers or developers. In many cases, the name is merely a mnemonic. Some reactions suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Organic Reactions
Well-known reactions and reagents in organic chemistry include 0-9 * 1,2-Wittig rearrangement * 1,3-Dipolar cycloaddition * 2,3-Wittig rearrangement A * Acetalisation * Acetoacetic ester condensation * Achmatowicz reaction * Acylation * Acyloin condensation *Adams' catalyst * Adams decarboxylation * Adkins catalyst * Adkins–Peterson reaction * Akabori amino acid reaction *Alcohol oxidation * Alder ene reaction * Alder–Stein rules * Aldol addition * Aldol condensation * Algar–Flynn–Oyamada reaction *Alkylimino-de-oxo-bisubstitution * Alkyne trimerisation * Alkyne zipper reaction * Allan–Robinson reaction *Allylic rearrangement * Amadori rearrangement * Amine alkylation * Angeli–Rimini reaction * Andrussov oxidation * Appel reaction * Arbuzov reaction, Arbusow reaction * Arens–Van Dorp synthesis, Isler modification * Aromatic nitration * Arndt–Eistert synthesis * Aston–Greenburg rearrangement * Auwers synthesis *Aza-Cope rearrangement *Azo coupling B * Baeyer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claisen Rearrangement Scheme
Claisen may refer to: * Rainer Ludwig Claisen, a German chemist **Claisen rearrangement, a reaction of a allyl vinyl ether to a γ,δ-unsaturated carbonyl **Claisen condensation The Claisen condensation is a carbon–carbon bond forming reaction that occurs between two esters or one ester and another carbonyl compound in the presence of a strong base. The reaction produces a β-keto ester or a β- diketone. It is named ..., a reaction between esters and carbonyl compounds in the presence of a strong base ** Ireland–Claisen rearrangement, a chemical reaction of an allylic ester with strong base ** Claisen isatin synthesis See also * 5243 Clasien, a minor planet {{Disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olefin Metathesis
In organic chemistry, Olefin Metathesis or Alkene Metathesis is an organic reaction that entails the redistribution of fragments of alkenes (olefins) by the Bond cleavage, scission and regeneration of carbon-carbon double bonds. Because of the relative simplicity of olefin metathesis, it often creates fewer undesired by-products and hazardous wastes than alternative organic reactions. For their elucidation of the reaction mechanism and their discovery of a variety of highly active Catalysis, catalysts, Yves Chauvin, Robert H. Grubbs, and Richard R. Schrock were collectively awarded the 2005 Nobel Prize in Chemistry. Catalysts The reaction requires catalysis, metal catalysts. Most commercially important processes employ heterogeneous catalysis, heterogeneous catalysts. The heterogeneous catalysts are often prepared by in-situ activation of a metal halide (MClx) using organoaluminium or organotin compounds, e.g. combining MClx–EtAlCl2. A typical catalyst support is alumina. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
