A Cyanohydrinreaction is an organic reaction organic chemical reaction by an aldehyde or ketone with a cyanide anion or a nitrile to form a cyanohydrin . This nucleophilic addition is a reversible reaction but with aliphatic carbonyl compounds equilibrium is in favor of the reaction products. The cyanide ... Cyanohydrin acetone reaction.svg thumb 400px center Reaction of acetone with sodium cyanide to hydroxyacetonitrile Image Benzoquinone cyanohydrin reaction.svg thumb 600px center Reaction of benzoquinone ... 6 Image Xylose cyanohydrin reaction.svg thumb 800px center chain extension of D xylose in equilibrium with its hemiacetal with KCN to the cyclic ester Reaction mechanism center Image Cyanohydrin mechanism 2D.png 400px Mechanism of the cyanohydrinreaction center Asymmetric synthesis The asymmetric synthesis asymmetric cyanohydrinreaction of benzaldehyde with trimethylsilylcyanide is made possible ... Complex. Image Asymetric cyanohydrin reaction.gif center Asymmetric reaction of benzaldehyde with R Binol lithium i propyloxy gives S cyanohydrin with 98 Enantiomer ee center small Asymmetric reaction of benzaldehyde with R Binol lithium i propyloxy gives S cyanohydrin with 98 Enantiomer ee small ... group CN C OH External links Cyanohydrinreaction of formaldehyde to hydroxyacetonitrile or glycolonitrile ... 56 http www.orgsyn.org orgsyn prep.asp?prep cv2p0387 Article Cyanohydrinreaction of formaldehyde with potassium ... orgsyn prep.asp?prep cv3p0436 Article Cyanohydrinreaction of acetophenone with potassium cyanide ...?prep cv4p0058 Article Cyanohydrinreaction of D xylose with potassium cyanide Organic Syntheses Coll ... Cyanohydrinreaction of acetone with potassium cyanide Organic Syntheses Coll. Vol. 2, p. 7 Vol. 15, p. 1 http www.orgsyn.org orgsyn prep.asp?prep cv2p0007 Article Cyanohydrinreaction of benzoquinone ... such as benzaldehyde , the benzoin condensation is a competing reaction. The reaction is used ... Catalyst for Cyanohydrin Synthesis Manabu Hatano, Takumi Ikeno, Takashi Miyamoto, and Kazuaki ... more details
Koch reaction formylation of arene s. Treatment of this cyanohydrin with lithium hydride affords anhydrous lithium cyanide Image LiCN from acetone cyanohydrin 2D skeletal.png 400px Other cyanohydrins ...Image Cyanohydrin general 2D skeletal.png thumb right size The structure of a general cyanohydrin. A cyanohydrin is a functional group found in organic compound s. Cyanohydrins have the formula R sub 2 sub C OH CN, where R is H, alkyl , or aryl . Cyanohydrins are industrially important precursors to carboxylic acid s and some amino acid s. Cyanohydrins can be formed by the cyanohydrinreaction , which involves treating a ketone or an aldehyde with hydrogen cyanide HCN in the presence of excess amounts of sodium cyanide NaCN as a catalyst RR C O HCN RR C OH CN In this reaction, the nucleophilic CN sup sup ion attacks the electrophilic carbonyl carbon in the ketone, followed by protonation by HCN, thereby regenerating the cyanide anion . Cyanohydrins are also prepared by displacement of sulfite by cyanide salts ref name Corson OrgSynth author Corson, B. B. Dodge, R. A. Harris, S. A. Yeaw, J. S. title Mandelic Acid collvol 1 collvolpages 336 year 1941 prep cv1p0336 ref Image Cyanation of aldehyde with bisulfate.svg 300px Cyanohydrins are intermediates in the Strecker amino acid synthesis . Acetone cyanohydrins Acetone cyanohydrin , CH sub 3 sub sub 2 sub C OH CN is the cyanohydrin of acetone ... Haroutounian, S. A. Acetone Cyanohydrin Encyclopedia of Reagents for Organic Synthesis 2001, John Wiley & Sons. DOI 10.1002 047084289X.ra014 ref Thus, acetone cyanohydrin can be used for the preparation ... . Glycolonitrile , also called hydroxyacetonitrile or formaldehyde cyanohydrin, is the organic compound with the formula HOCH sub 2 sub CN. It is the simplest cyanohydrin, being derived from formaldehyde ... 100px center center glycolonitrile center center acetone cyanohydrin center center mandelonitrile ... www.iupac.org goldbook C01489.pdf Category functional groups Category Cyanohydrins da Cyanohydrin de ... more details
chembox verifiedrevid 443658192 ImageFile Acetone cyanohydrin.svg ImageFile2 Acetone cyanohydrin 3D.png IUPACName 2 hydroxy 2 methylpropanenitrile OtherNames Section1 Chembox Identifiers KEGG Ref keggcite correct kegg KEGG C02659 InChI 1 C4H7NO c1 4 2,6 3 5 h6H,1 2H3 InChIKey MWFMGBPGAXYFAR UHFFFAOYAL StdInChI Ref stdinchicite correct chemspider StdInChI 1S C4H7NO c1 4 2,6 3 5 h6H,1 2H3 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey MWFMGBPGAXYFAR UHFFFAOYSA N CASNo 75 86 5 CASNo Ref cascite correct CAS EC number 200 909 4 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 6166 PubChem 6406 ChEBI Ref ebicite correct EBI ChEBI 15348 DrugBank Ref drugbankcite correct drugbank DrugBank DB02203 SMILES N CC O C C Section2 Chembox Properties Formula C sub 4 sub H sub 7 sub NO MolarMass 85.105 g mol Appearance Density 0.932 g cm sup 3 sup MeltingPt 19 C BoilingPt 95 C Solubility Section7 Chembox Hazards ExternalMSDS https fscimage.fishersci.com msds 11030.htm Fisher MSDS EUIndex 608 004 00 X NFPA H 4 NFPA F 1 NFPA R 2 FlashPt Autoignition Acetone cyanohydrin ACH is an organic compound used in the production of methyl methacrylate , the monomer of the transparent plastic polymethyl methacrylate PMMA , also known as acrylic. Preparation The compound is generated as part of the acetone cyanohydrin route to methyl methacrylate. It is treated with sulfuric acid to give the sulfate ester of the methacrylamide, methanolysis of which gives ammonium bisulfate and MMA ... title Acetone Cyanohydrin prep cv2p0007 collvol 2 collvolpages 7 ref Image Synthesis of acetone cyanohydrin.png .... Crushing the tubers releases these compounds and produces acetone cyanohydrin, which is potentially lethally toxic. Safety Acetone cyanohydrin is classified as an List of extremely hazardous substances ... hazards of acetone cyanohydrin arise from its ready decomposition on contact with water ... cyanohydrin id 75865 Category Cyanohydrins cs Acetonkyanhydrin de Acetoncyanhydrin fr Cyanohydrine ... more details
Vector version available Cyanohydrin acetone reaction.svg cyanohydrin acetone reaction PD self date October 2006 Category PD chem Category Classified Chemical Structures ... more details
enzyme Name cyanohydrin beta glucosyltransferase EC number 2.4.1.85 CAS number 55354 52 4 IUBMB EC number 2 4 1 85 GO code 0047792 image width caption In enzymology , a cyanohydrin beta glucosyltransferase EC number 2.4.1.85 is an enzyme that catalysis catalyzes the chemical reaction UDP D glucose S 4 hydroxymandelonitrile math rightleftharpoons math UDP S 4 hydroxymandelonitrile beta D glucoside Thus, the two substrate biochemistry substrates of this enzyme are UDP D glucose and S 4 hydroxymandelonitrile , whereas its two product chemistry products are uridine diphosphate UDP and S 4 hydroxymandelonitrile beta D glucoside . This enzyme belongs to the family of glycosyltransferase s, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP D glucose S 4 hydroxymandelonitrile beta D glucosyltransferase . Other names in common use include uridine diphosphoglucose p hydroxymandelonitrile , glucosyltransferase , UDP glucose p hydroxymandelonitrile glucosyltransferase , uridine diphosphoglucose cyanohydrin glucosyltransferase , uridine diphosphoglucose aldehyde cyanohydrin , beta glucosyltransferase , UDP glucose S 4 hydroxymandelonitrile beta D glucosyltransferase , UGT85B1 , and UDP glucose p hydroxymandelonitrile O glucosyltransferase . This enzyme participates in tyrosine metabolism and cyanoamino acid metabolism . References reflist 1 cite journal author Reay PF, Conn EE date 1974 title The purification and properties of a uridine diphosphate glucose aldehyde cyanohydrin beta glucosyltransferase from sorghum seedlings journal J. Biol. Chem. volume 249 pages 5826&ndash 30 pmid 4416442 issue 18 cite journal author Jones PR, Moller BL, Hoj PB date 1999 title The UDP glucose p hydroxymandelonitrile O glucosyltransferase that catalyzes the last step in synthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor. Isolation, cloning, heterologous ... substrate regiospecificity of recombinant UGT85B1, the cyanohydrin glucosyltransferase from ... more details
Wiktionary reactionReaction may refer to Response disambiguation Response to another event Adverse drug reaction Chemical reaction Emotional reaction Light reaction Nuclear reaction TNA Reaction , a documentary show of Total Nonstop Action Wrestling TNA behind scenes. Reaction physics , as defined by Newton s third law Reactionary , a political tendency Reflex reaction other uses Reaction Records , a record label ReAction GUI a GUI toolkit used on AmigaOS Reaction software , a Perl application framework Reaction song Reaction song , a 1986 song by American R&B singer Rebbie Jackson Reaction , a 2008 single by Dead Letter Circus Disambiguation als Reaktion ar bg cs Reakce de Reaktion et Reaktsioon el es Reacci n eo Reakcio fa fr R action gl Reacci n ko hr Reakcija it Reazione nl Reactie ja no Reaksjon pl Reakcja pt Rea o ro Reac ie ru simple Reaction sr Reakcija fi Reaktio uk zh ... more details
A homologation reaction , also known as homologization , is any chemical reaction that converts the reactant into the next member of the homologous series . A Homologous series is a group of compounds that differ by a constant unit, generally a CH sub 2 sub group. The reactants undergo a homologation when the number of a repeated structural unit in the molecules is increased. The most common homologation reactions increase the number of methylene CH sub 2 sub units in saturated chain within the molecule. ref Encyclopedia of Inorganic Chemistry DOI 10.1002 0470862106.id396 ref For example the reaction of aldehyde s or ketone s with diazomethane or methoxymethylenetriphenylphosphine to give the next homologue in the series. Examples of homologation reactions include Kiliani Fischer synthesis , where an aldose molecule is elongated through a three step process consisting of Nucleophillic addition of cyanide to the carbonyl to form a cyanohydrin Hydrolysis to form a lactone Reduction to form the homologous aldose Wittig reaction of an aldehyde with methoxymethylenetriphenylphosphine , which produces a homologous aldehyde. Arndt Eistert reaction is a series of chemical reactions designed to convert a carboxylic acid to a higher carboxylic acid homologue i.e. contains one additional carbon atom Kowalski ester homologation , an alternative to the Arndt Eistert synthesis. Has been used to convert amino esters from amino esters through an ynolate intermediate. ref cite journal author D. Gray, C. Concellon and T. Gallagher title Kowalski Ester Homologation. Application to the Synthesis ... , organic reduction of chlorine to methylketone 5 , ketone halogenation to 6 , elimination reaction ... Gallagher Hollander Degradation.svg 600px Gallagher Hollander Degradation In the Hooker reaction .... 1936 58 7 pp 1179 1181 DOI 10.1021 ja01298a031 ref Image HookerReaction.svg 500px Hooker reaction ... Homologation Reaction Category Carbon carbon bond forming reactions it Omologazione chimica ... more details
A reaction step of a chemical reaction is defined as An elementary reaction , constituting one of the stages of a stepwise reaction in which a reaction intermediate or, for the first step, the reactants is converted into the next reaction intermediate or, for the last step, the product chemistry products in the sequence of intermediates between reactants and products . ref http goldbook.iupac.org R05178.html IUPAC Gold Book definition of reaction step ref Notes reflist Category Chemical kinetics physical chemistry stub et Reaktsiooni staadium pt Etapa de rea o ... more details
The Carbylamine reaction is a chemical test for detection of primary amine s. In this reaction, the analyte is heated with alcoholic potassium hydroxide and chloroform. If a primary amine is present, the isocyanide is formed. For example, the reaction with ethylamine Image Carbylamine.png 500px The carbylamine reaction with ethyl amine The reaction with aniline File Aniline carbylamine reaction.png 500px The carbylamine reaction with aniline The carbylamine test does not give a positive reaction with secondary and tertiary amines. References http www.books about california.com Pages Experimental Organic Chemistry Ex Organic Chem Chap 09.html Carbylamine reaction Category Organic reactions Category Chemical tests es Reacci n carbilamina ta ... more details
The Bunsen Reaction is a chemical reaction that describes water, sulfur dioxide , and iodine reacting to form sulfuric acid and hydrogen iodide . This reaction is the first step in the Sulfur iodine cycle to produce hydrogen . 2H sub 2 sub O SO sub 2 sub I sub 2 sub H sub 2 sub SO sub 4 sub 2HI The reaction is named after Robert Bunsen . A similar reaction is the basis for Karl Fischer titration . unreferenced date October 2007 Category Inorganic reactions reaction stub nl Bunsen reactie ... more details
The Pellizzari reaction is the chemical reaction of an amide and a hydrazide to form a 1,2,4 triazole . ref Pellizzari, G. Gazz. Chim. Ital. 1911 , 41 , 20. ref Image Pellizzari Reaction Scheme.png center 400px The Pellizzari reaction References Reflist See also Einhorn Brunner reactionreaction stub Category Condensation reactions Category Heterocycle forming reactions Category Name reactions es Reacci n de Pellizzari id Reaksi Pellizzari nl Pellizzari reactie ja zh ... more details
The Kochi reaction is an organic reaction for the decarboxylation of carboxylic acid s to alkyl halide s with lead tetraacetate and a lithium chloride or other lithium salts ref A New Method for Halodecarboxylation of Acids Using Lead IV Acetate Jay K. Kochi J. Am. Chem. Soc. 1965 87 11 2500 2502. DOI 10.1021 ja01089a041 ref . Image Kochi reaction.png The Kochi reaction 550px The reaction is a variation of the Hunsdiecker reaction . References Reflist DEFAULTSORT Kochi Reaction Category Organic reactions Category Name reactions de Kochi Reaktion pl Reakcja Kochiego zh Kochi ... more details
The Fernandez reaction is reaction that occurs to signal a positive result in the lepromin skin test for leprosy . The reaction occurs in the skin at the site of injection if the body possesses antibody antibodies to the Dharmendra antigen , one of the antigen s found in Mycobacterium leprae , the bacteria that causes leprosy. The reaction occurs via a delayed type hypersensitivity mechanism. This reaction occurs within 48 hours of injection of lepromin and is seen in both lepromatous and tuberculoid forms of leprosy. In contrast, the Mitsuda reaction occurs 5 6 weeks after injection of lepromin and is only seen in patients with the tuberculoid form of leprosy not the lepromatous form, in which the body does not mount a strong response against the bacterium . In terms of mechanism of action and appearance, the reaction is similar to the tuberculin reaction of a positive Mantoux test for tuberculosis . Category Skin tests Category Leprosy medical stub ... more details
The Doebner reaction is the chemical reaction of an aniline with an aldehyde and pyruvic acid to form quinoline 4 carboxylic acid s. ref Doebner, O. Ann. 1887 , 242 & 265. ref ref Bergstrom, F. W. Chem. Rev. 1944 , 35 , 156. Review ref Image Doebner Reaction Scheme.png center 350px The Doebner reaction References Reflist See also Conrad Limpach reaction Doebner Miller reactionreaction stub Category Carbon carbon bond forming reactions Category Condensation reactions Category Quinoline forming reactions Category Multiple component reactions Category Name reactions ar es S ntesis de quinolinas de Doebner zh ... more details
In chemistry , a concerted reaction is a chemical reaction in which all bond breaking and bond making occurs in a single step. Reactive intermediate s or other unstable high energy intermediates are not involved. Concerted reaction rate s tend not to depend on solvent Chemical polarity polarity ruling out large buildup of electrical charge charge in the transition state . Pericyclic reactions are concerted reactions. In the SN2 S sub N sub 2 reaction a concerted reaction also takes place. Because the reaction rate is bimolecular there are two molecular species controlling the rate of the reaction. Because the rate is dependent on two molecules the reaction does not have any intermediate steps, only a transition state . This means that all the bond making and bond breaking takes place in a single step. In order for the reaction to occur both molecules must be situated correctly. Therefore, the reaction is said to be concerted because it occurs in one step. References Carey, Francis A. Sundberg, Richard J. 1984 . Advanced Organic Chemistry Part A Structure and Mechanisms 2nd ed. . New York N.Y. Plenum Press. ISBN 0 306 41198 9. Category organic reactions ar es Reacci n concertada fr R action concert e nl Concerted reactie pl Reakcja skoordynowana pt Rea o concertada zh ... more details
The Bosch reaction is a chemical reaction between carbon dioxide and hydrogen that produces elemental carbon graphite , water and a 10 return of invested heat . This reaction requires the introduction of iron as a catalyst and requires a temperature level of 530 730 degrees Celsius. ref Messerschmid, Ernst and Reinhold Bertrand. Space Stations. Springer. 1999. ref The overall reaction is as follows CO sub 2 sub gas g 2 H sub 2 sub g C solid s 2 H sub 2 sub O g The above reaction is actually the result of two reactions. The first reaction, the reverse water gas shift reaction , is a fast one. CO sub 2 sub H sub 2 sub CO H sub 2 sub O The second reaction controls the reaction rate . CO H sub 2 sub C H sub 2 sub O The overall reaction produces 2.3× 10 sup 3 sup joule s for every gram of carbon produced at 650 C. Reaction temperatures are in the range of 450 to 600 C. The reaction can be accelerated in the presence of an iron , cobalt or nickel catalyst . Ruthenium also serves to speed up the reaction. Together with the Sabatier reaction the Bosch reaction is studied as a way to remove carbon dioxide and to generate clean water aboard a space station ref http oregonstate.edu atwaterj h2o gen.htm Methods of water production ref The reaction is also used to produce graphite for radiocarbon dating with Accelerator Mass Spectrometry . It is named after the German chemist Carl Bosch . Citation needed date March 2008 The Bosch reaction is being investigated for use in maintaining space station life support. Though the Bosch reaction would present a completely closed hydrogen and oxygen cycle which only produces atomic carbon as waste, difficulties maintaining its higher required temperature and properly handling carbon deposits mean significantly more research will be required ... carbon tends to foul the catalyst s surface, which is detrimental to the reaction s efficiency ... A carbon dioxide reduction unit using Bosch reaction Category Organic redox reactions Category ... more details
The Povarov reaction is an organic reaction described as a formal cycloaddition between an aromatic imine and an alkene . The imine in this organic reaction is a condensation reaction product from an aniline ... be able to donate electrons. Such alkenes are enol ether s and enamine s. The reaction product in the original Povarov reaction is a quinoline . Because the reactions can be carried out with the three components premixed in one reactor it is an example of a multi component reaction . Image Povarov reaction general.svg Povarov reactionReaction mechanism The reaction mechanism for the Povarov reaction ... base in a condensation reaction . The Povarov reaction requires a lewis acid such as boron trifluoride to activate the imine for an electrophilic addition of the activated alkene . This reaction ... substitution . Two additional elimination reaction s create the quinoline ring structure. Image PovarovReaction.gif frame center Scheme 1 . The Povarov reaction The reaction is also classified as a subset of aza Diels Alder reaction s ref Recent synthetic developments in a powerful imino Diels Alder reaction Povarov reaction application to the synthesis of N polyheterocycles and related alkaloids ... ref Examples The reaction depicted in scheme 2 illustrates the Povarov reaction with an imine ... in Povarov reaction of benzylidene 3 nitrophenyl amine Paul J. Stevenson and Isla Graham ... ref . This reaction is regioselective because the iminium ion preverentially attacks the nitro ..., the most electron rich ring position is now ortho and not para. The reaction is also Diastereomer ... 2 regio and diastereoselective Povarov reaction Variations One variation of the Povarov reaction is a four component reaction ref Straightforward Access to a Structurally Diverse Set of Oxacyclic Scaffolds through a Four Component Reaction Oscar Jim nez, Guillermo de la Rosa, Rodolfo Lavilla Angewandte ... cgi bin abstract 112092897 ABSTRACT Abstract ref . Whereas in the traditional Povarov reaction ... more details
An exergonic reaction is a chemical reaction where the change in the Gibbs free energy is negative, ref IUPAC Gold Book definition http www.iupac.org goldbook E02262.pdf search Exergonic 20reaction exergonic exoergic reaction ref indicating a spontaneous reaction . Symbolically, the release of Gibbs free energy, G , in an exergonic reaction is denoted as math Delta G G rm products G rm reactants 0. , math Although exergonic reactions are said to occur spontaneously , this does not imply that the reaction will take place at an observable Reaction rate rate . For instance, the Catalysis Background disproportionation of hydrogen peroxide is very slow in the absence of a suitable catalyst. It has been suggested that eager would be a more intuitive term in this context. ref cite journal doi 10.1021 ed061p710 last Hamori first Eugene coauthors James E. Muldrey year 1984 title Use of the world eager instead of spontaneous for the description of exergonic reactions journal Journal of Chemical Education volume 61 issue 8 pages 710 ref More generally, the terms exergonic and endergonic relate to the Gibbs free energy change in any process, not just chemical reactions. An example of an exergonic reaction is cellular respiration. The terms exothermic and endothermic reactions relate to the enthalpy change of a process. See also Endergonic reaction References reflist Category Thermochemistry de Exergon pl Reakcja egzoenergetyczna ... more details
unreferenced date May 2009 In thermochemistry chemical thermodynamics , an endergonic reaction also called an unfavorable reaction or a nonspontaneous reaction is a chemical reaction in which the standard change in Thermodynamic free energy free energy is positive, and energy is absorbed. In layman s terms the total amount of energy is a loss it takes more energy to start the reaction than what you ... Exergonic reaction Exergonic Reaction . Under constant temperature and constant pressure conditions ... 0 math for the reaction at standard state ie at standard pressure 1 Bar unit bar , and standard concentrations ... constant for the reaction is related to G by the relation math K e frac Delta G circ RT math where ... math K 1 , math so that starting from molar stoichiometric quantities such a reaction would move ... in Free Energy process. Pull Reagents can be pulled through an endergonic reaction, if the reaction products are cleared rapidly by a subsequent exergonic reaction. The concentration of the products of the endergonic reaction thus always remains low, so the reaction can proceed. A classic example of this might be the first stage of a reaction which proceeds via a transition state . The process of getting .... However, the reaction can proceed because having reached the transition state, it rapidly ... by coupling them to another reaction which is strongly exergonic, through a shared intermediate. This is often how biological reactions proceed. For example, on its own the reaction math X Y longrightarrow ... it to a strongly exergonic reaction such as, very often, the decomposition of Adenosine triphosphate ... XY P i math This kind of reaction, with the ATP decomposition supplying the free energy needed to make an endergonic reaction occur, is so common in cell biochemistry that ATP is often called the universal energy currency of all living organisms. See also Endergonic Exergonic Exergonic reaction Exothermic Endothermic Exothermic reaction Endothermic reaction Warm blooded Endotherm Warm blooded ... more details
Image Samariumiodide.jpg thumb 170px right Barbier reaction with samarium II iodide The Barbier reaction is an organic reaction between an alkyl halide and a carbonyl group as an electrophilic substrate in the presence of magnesium , aluminium , zinc , indium , tin or its salts. The reaction product is a primary, secondary or tertiary alcohol . The reaction is similar to the Grignard reaction but the crucial difference is that the Barbier reaction is a one pot synthesis whereas a Grignard reagent is prepared separately before addition of the carbonyl compound. ref cite journal author Barbier, P ... in many cases to run the reaction in water which makes the procedure part of green chemistry . The Barbier reaction is named after Victor Grignard s teacher Philippe Barbier . Examples of Barbier reactions are the reaction of propargylic bromide with butanal with zinc metal in water ref cite journal title Zn Mediated Regioselective Barbier Reaction of Propargylic Bromides in THF aq. NH4Cl Solution ... BarbierReaction1.png 507px center Barbier reaction center small With a substituted alkyne instead of a terminal alkyne the allene product is favoured small center the intramolecular Barbier reaction with samarium II iodide ref cite journal title Preparation of oxo substituted chloro ethers and their reaction ... 442px center Barbier reaction the reaction of an allyl bromide with formaldehyde in THF ... 502px center Barbier reaction center small The Barbier reaction is accompanied by an allylic rearrangement to a terminal alkene small center or another allyl bromide in a reaction with benzaldehyde ... Aqueous Barbier Grignard Reaction author Gary W. Breton, John H. Shugart, Christine A. Hughey ... 464px center Barbier reaction center small The observed diastereoselectivity for this reaction is erythro threo 83 17 small center Related reactions Grignard reaction , Nozaki Hiyama Kishi reaction External links Barbier reaction University of Connecticut http orgchem.chem.uconn.edu ... more details
The Passerini reaction is a chemical reaction involving an isocyanide , an aldehyde or ketone , and a carboxylic acid to form a acyloxy amide . ref Passerini, M. Simone, L. Gazz. Chim. Ital. 1921 , 51 , 126 129. ref ref Passerini, M. Ragni, G. Gazz. Chim. Ital. 1931 , 61 , 964 969. ref ref cite journal author Banfi, L. Riva, R. journal Org. React. year 2005 volume 65 pages 1 140 doi 10.1002 0471264180.or065.01 title The Passerini Reaction . ref File Passerini reaction.svg 498px center The Passerini reaction This organic reaction was discovered by Mario Passerini in 1921 in Florence , Italy . It is the first isocyanide based multi component reaction developed, and currently plays a central role ... ref Reaction mechanism Two different reaction pathways have been hypothesized. Ionic mechanism In polar solvents such as methanol or water molecule water , the reaction proceeds by protonation ... the desired ester 5 Fact date January 2008 . Image Passerini Reaction Mechanism.png 500px center The mechanism of the Passerini reaction Concerted mechanism In non polar solvents and at high concentration a concerted mechanism is likely ref The Passirini Reaction L. Banfi, R.Riva in Organic Reactions ... center Trimolecular Passerini reaction mechanism This mechanism involves a trimolecular reaction ... bonding. The second step of the Passerini reaction is an acyl transfer to the neighboring hydroxyl group. There is support for this reaction mechanism the reaction proceeds in relatively non polar solvent s in line with transition state and the reaction kinetics depend on all three reactant s. This reaction ... multicomponent reaction s for instance one preceded by a Horner Wadsworth Emmons reaction and forming a depsipeptide ref A Flexible Six Component Reaction To Access Constrained Depsipeptides Based on a Dihydropyridinone ... 10.1021 jo701978v ref Image SixComponentreactionParavidino2007.svg center 500px Six component reaction ... ja1113003 ref See also Ugi reaction References Reflist Category Carbon carbon bond forming reactions ... more details
A reaction video is a genre of short amateur video that captures the reaction of an individual or group of individuals as they encounter a particular text, usually a short media clip . History and Examples The first massively popular reaction videos emerged in mid 2007, when thousands of YouTube rs uploaded their reactions, often a combination of laughter and retching to a trailer for a particularly graphic adult film called 2 Girls 1 Cup . The trailer has spawned many reaction videos on the Internet, some of which have attracted many millions of views. In 2008, another batch of reaction videos emerged around the viral video Scarlet Takes a Tumble, a video in which an obese woman sings and dances and then falls off a coffee table. That same year, Twilight 2008 film Twilight fans uploaded reaction videos that captured their affect as they watched the trailer for the film for the first time. References references Category Internet Category Internet memes ... more details
The Tishchenko reaction is a chemical reaction that involves disproportionation of an aldehyde lacking a hydrogen atom in the alpha position in the presence of an alkoxide . Ref 1 The reaction product is an ester . Catalyst s are aluminium alkoxides or sodium alkoxides. Benzaldehyde reacts with sodium benzyloxide generated from sodium and benzyl alcohol to benzyl benzoate . Ref 2 Image Tishchenko reaction.gif center The Tishchenko reaction benzaldehyde reacts to benzyl benzoate, the catalyst is generated in situ from sodium and benzyl alcohol formaldehyde Paraformaldehyde reacts with boric acid to methyl formate . Ref 3 The key step in the reaction mechanism for this reaction is a 1,3 hydride shift in the hemiacetal intermediate formed from two successive nucleophilic addition reactions, the first one from the catalyst. The hydride shift regenerates the alkoxide catalyst. Image Tishchenko reaction mechanism.gif center The Tishchenko reactionreaction mechanism In the related Cannizzaro reaction the base is sodium hydroxide and then the organic oxidation oxidation product is a carboxylic acid and the organic reduction reduction product is an alcohol . Related reactions Aldol Tishchenko reaction Baylis Hillman reaction Cannizzaro reaction Meerwein Ponndorf Verley Reduction Oppenauer Oxidation References Note 1 V. Tishchenko, J. Russ. Phys. Chem. Soc. 1906 , 38 , 355, 482, 540, 547. Note 2 OrgSynth author Kamm, O. Kamm, W. F. title Benzyl benzoate collvol 1 collvolpages 104 year 1941 prep cv1p0104 Note 3 cite journal author Paul R. Stapp journal J. Org. Chem. year 1973 volume 38 issue 7 pages 1433 1434 doi 10.1021 jo00947a049 title Boric acid catalyzed Tishchenko reactions Category Organic reactions Category Name reactions de Claisen Ti enko Reaktion ja zh es Reacci n ald lica de Tishchenko ... more details
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