4 TVB Jade Midnight rerun List of TVB series 2007 2007 br ArmedReaction br February 22 March ... rerun List of TVB series 2009 2009 br ArmedReaction II br March 6 April 20 br 12 05am to 1 05am br ArmedReaction III br April 21 June 3 br 12 15am to 1 15am br ArmedReaction IV br June 4 July ... 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
Infobox musical artist See Wikipedia WikiProject Musicians name The Armed image caption From left to right Adam Senko, Chris Elkjar, Kenny Szymanski, Tony Wolski, Dan Greene, and Aaron Jones. image size 350 background group or band origin Detroit, Michigan , United States genre Hardcore punk , metalcore years active 2009 present associated acts Slicer Dicer, The Dillinger Escape Plan , Coheed and Cambria website URL http www.thearmed.com current members Adam Senko br Chris Elkjar br Kenny Szymanski br Tony Wolski br Dan Greene br Aaron Jones The Armed is a six piece band from Detroit, Michigan Detroit , Michigan playing a blend of hardcore punk and extreme metal since 2009. Three of its members Chris Elkjar, Tony Wolski, and Aaron Jones were previously in another Detroit based hardcore punk band, Slicer Dicer. The Armed play several Slicer Dicer songs in live shows and included two, Terrordactyl and Buy A Snake, on their first full length album, These Are Lights . Description The group ... 7, 2009. ref They broke up in late 2008, but three of their members went on to form The Armed and have continued to have a similarly energetic live show. ref http www.vimeo.com 5170931 The Armed ... Gonella at New Alliance East. ref cite web url http www.smnnews.com 2009 09 14 the armed plop kurt ballou mixed debut online for download title The Armed Plop Kurt Ballou Mixed Debut Online for Download ... http hyperbolemachine.com 2010 03 30 artist spotlight the armed title Artist Spotlight The Armed publisher ..., 2010. ref cite web url http www.friendsthroughcommonenemies.com title The Armed publisher Friendsthroughcommonenemies.com ... The Armed Home publisher Thearmed.bigcartel.com date accessdate 2010 12 30 ref The album features ... on The Armed s New EP publisher SMNnews.com date 2010 03 25 accessdate 2010 12 30 ref Their stage ... the armed Hyperbole Machine Interview http www.thrashhits.com 2009 12 the armed we want the airwaves back Thrash Hits Interview The Armed DEFAULTSORT Armed Category American metalcore musical groups ... more details
Thoroughbred racehorse infobox horsename Armed image caption sire Bull Lea grandsire Bull Dog horse Bull Dog dam Armful damsire Chance Shot horse Chance Shot sex Gelding foaled 1941 country United States colour Brown color Brown breeder Calumet Farm owner Calumet Farm trainer Ben A. Jones record 81 41 20 10 earnings 817,475 race Washington Handicap 1945 br Suburban Handicap 1946 br Widener Handicap 1946, 1947 br Washington Park Handicap 1946, 1947 br Stars and Stripes Breeders Cup Turf Handicap Stars and Stripes Handicap 1947 br Gulfstream Park Handicap 1947 br Arlington Handicap 1947 br McLennan Handicap McLennan Memorial Handicap 1947 awards American Champion Older Male Horse U.S. Champion Older Male Horse 1946 & 1947 br American Horse of the Year United States Horse of the Year 1947 honours National Museum of Racing and Hall of Fame 1963 br Blood Horse magazine List of the Top 100 Racehorses of the 20th Century 39 Top 100 U.S. Racehorses of the 20th Century updated October 12, 2007 Armed May, 1941 1964 was an United States American Thoroughbred gelding horse racing race horse . He was sired by the great graded stakes race stakes winner Bull Lea , which made him a half brother to Citation horse Citation . His dam was Armful, whose sire was Belmont Stakes winner Chance Shot horse Chance Shot , and whose grandsire was the great Fair Play horse Fair Play . Small for his age and very headstrong, Armed s habit of biting and kicking hay out of his handler s pitchfork , along with being ... once in five starts and had to be rested due to an ankle injury. Armed raced for seven seasons, from ... as American Champion Older Male Horse plus was voted 1947 American Horse of the Year honors. Armed died ... 1965 publisher Daily Racing Form pages 1336 ref In 1963, Armed was inducted into National Museum of Racing ... 39. References reflist http www.pedigreequery.com armedArmed s pedigree http www.tbhorsepedigree.com library horse Armed.php TB Library profile of Armed by Avalyn Hunter External links http www.kyhorsepark.com ... 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
Unreferenced stub auto yes date December 2009 Reaction shot is a term used in motion picture film production production and cinematography referring to a basic unit of film grammar. It is a shot which cuts away from the main scene in order to show the reaction of a character to it. A reaction shot usually implies the display of some sort of emotion on the face of the actor being shown, and is thus most commonly a close up shot although a group of actors may be shown reacting together . A reaction shot is also generally bereft of dialogue , though this is not an absolute rule. Its main purpose is to show an emotional response to the immediately preceding action or words of another character in the scene, or to an event in the immediately preceding scene which may or may not involve another actor e.g., an explosion, monster, empty room, etc. The assumption behind the logic of the reaction shot is that the emotional reaction of the actor being depicted will either advance the story forward, reveal character traits of the character in the reaction shot, or emphasize character traits of another character that were displayed in the action or dialog present in the preceding shot. A completely unemotional reaction may also be important if it provides information to the audience or is unexpected in the context of the scene. Reaction shots can be especially critical in comedy , as the reaction of an actor or actors to a dramatic incident provides a psychological cue to the audience about how to respond to that incident themselves. In some cases the deliberate avoidance of showing a reaction shot can be used by a filmmaker to dramatic effect for instance, if the filmmaker does not want the audience to see a character s reaction to a particular incident at that point in time. DEFAULTSORT Reaction Shot Category Film techniques Film term stub ... more details
chem stub Reactionbox verifiedrevid Reference Type ring condensation NamedAfter W. Pfitzinger Section1 Reactionbox Conditions Solvent protic Reaction Reactionbox Reaction Reactant1 ketone or aldehyde Reactant2 isatin Reactant3 potassium hydroxide Product1 quinoline 4 carboxylic acid Sideproduct1 water The Pfitzinger reaction also known as the Pfitzinger Borsche reaction is the chemical reaction of isatin with base and a carbonyl compound to yield substituted quinoline 4 carboxylic acid s. ref Pfitzinger, W. J. Prakt. Chem. 1886 , 33 , 100. ref ref Pfitzinger, W. J. Prakt. Chem. 1888 , 38 , 582. ref Image Pfitzinger Reaction Scheme.png center 400px The Pfitzinger reaction Several reviews have been published. ref Manske, R. H. Chem. Rev. 1942 , 30 , 126. Review ref ref Bergstrom, F. W. Chem. Rev. 1944 , 35 , 152. Review ref ref Shvekhgeimer, M. G. A. Chemistry of Heterocyclic Compounds 2004 , 40 , 257 294. Review, DOI 10.1023 B COHC.0000028623.41308.e5 ref Reaction mechanism Image Pfitzinger Reaction Mechanism.png center 650px The mechanism of the Pfitzinger reaction The reaction of isatin with a base such as potassium hydroxide hydrolysis hydrolyses the amide bond to give the keto acid 2 . This intermediate can be isolated, but is typically not. A ketone or aldehyde will react with the aniline to give the imine 3 and the enamine 4 . The enamine will cyclize and dehydrate to give the desired quiniline 5 . Variations Halberkann variant Image Pfitzinger Halberkann Modification Scheme.png center 350px The Halberkann variant of the Pfitzinger reaction Reaction of N acyl isatins with base gives 2 Hydroxyl hydroxy quinoline 4 carboxylic acid s. ref Halberkann, J. Chemische Berichte Ber. 1921 , 54 , 3090. ref References Reflist See also Camps quinoline synthesis Friedl nder synthesis Niementowski quinazoline synthesis Category Carbon carbon bond forming reactions Category Condensation reactions Category Quinoline forming reactions Category Name reactions de Pfitzinger Reakti ... more details
The Pr vost reaction is chemical reaction in which an alkene is converted by iodine and the silver salt chemistry salt of benzoic acid to a Vicinal chemistry vicinal diol with anti addition anti stereochemistry. ref cite journal author Charles Pr vost journal Comptes rendus volume 196 pages 1129 year 1933 title Sur un complexe iodo argento benzo que et son application l oxydation des combinaisons thyl niques en glycols url http gallica.bnf.fr ark 12148 bpt6k3148d f1129.table ref ref Charles Pr vost C.A. 27, 3195 1933 ref ref Wilson, C. V. Org. React. 1950 , 9 , 350. Review ref The reaction was discovered by the French chemist Charles Pr vost 1899 1983 . Image Prevost Reaction Scheme.png center 500px The Pr vost reactionReaction mechanism The reaction between silver benzoate 1 and iodine is very fast and produces a very reactive iodinium benzoate intermediate 2 . The reaction of the iodinium salt 2 with an alkene gives another short lived iodinium salt 3 . Nucleophilic substitution SN2 reaction S sub N sub 2 by the benzoate salt gives the ester 4 . Another silver ion causes the anchimeric assistance neighboring group substitution of the benzoate ester to gives the oxonium ion oxonium salt 5 . A second SN2 reaction S sub N sub 2 substitution by the benzoate anion give the desired diester 6 . Image Prevost Reaction Mechanism.png center 600px The mechanism of the Pr vost reaction In the final step hydrolysis of the ester groups gives the anti diol. This outcome is the opposite of that of the related Woodward cis hydroxylation which gives syn addition . References Reflist See also Woodward cis hydroxylation DEFAULTSORT Prevost Reaction Category Organic redox reactions Category Substitution reactions Category Name reactions de Pr vost Hydroxylierung zh ... more details
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