Organic reactions substitutions

Kinds of Catalyzed Organic Reactions A fundamental classification of organic reactions is possible on the basis of the lands of bonds that are formed or destroyed and the natures of eliminations, substitutions, and additions of groups. Here a more pragmatic hst of 20 commercially important lands or classes of reactions will be discussed. In all instances of sohd-catalyzed reactions, chemisorption is a primary step. Often molecules are dissociated on chemisorption into... 

Electrophilic aromatic substitution reactions are important for synthetic purposes and also are one of the most thoroughly studied classes of organic reactions from a mechanistic point of view. The synthetic aspects of these reactions are discussed in Chapter 11 of Part B. The discussion here will emphasize the mechanisms of several of the most completely studied reactions. These mechanistic ideas are the foundation for the structure-reactivity relationships in aromatic electrophilic substitution which will be discussed in Section 10.2... 

Quantitative structure-reactivity analysis is one of the most powerful tools for elucidating the mechanisms of organic reactions. In the earliest study, Van Etten et al. 71) analyzed the pseudo-first-order rate constants for the alkaline hydrolysis of a variety of substituted phenyl acetates in the absence and in the presence of cyclodextrin. The... 

Organic chemical reactions can be organized broadly in two ways—by what kinds of reactions occur and by how those reactions occur. Let s look first at the kinds of reactions that take place. There are four general types of organic reactions additions, eliminations, substitutions, and reammgements. 

Problem 29.8 Look at the entire glycolysis pathway and make a list of the kinds of organic reactions that take place—nucleophilic acyl substitutions, aldol reactions, ElcB reactions, and so forth. 

Classify an organic reaction as addition, elimination, condensation, or substitution. 

Addition and substitution reactions of nitrile-stabilized carbanions S. Arseniyadis, K. S. Kyler and D. S. Watt, Organic Reactions 31,1 (1984). Note. Includes ArC (OTMS)CN, and HetAr (OTMS)CN. 

The electophilic substitution of allylsilanes and vinylsilanes I, Fleming, J. Dunogues and R. Smithers, Organic Reactions 37, Chapter 2 (1990). 

In Part 2 of this book, we shall be directly concerned with organic reactions and their mechanisms. The reactions have been classified into 10 chapters, based primarily on reaction type substitutions, additions to multiple bonds, eliminations, rearrangements, and oxidation-reduction reactions. Five chapters are devoted to substitutions these are classified on the basis of mechanism as well as substrate. Chapters 10 and 13 include nucleophilic substitutions at aliphatic and aromatic substrates, respectively, Chapters 12 and 11 deal with electrophilic substitutions at aliphatic and aromatic substrates, respectively. All free-radical substitutions are discussed in Chapter 14. Additions to multiple bonds are classified not according to mechanism, but according to the type of multiple bond. Additions to carbon-carbon multiple bonds are dealt with in Chapter 15 additions to other multiple bonds in Chapter 16. One chapter is devoted to each of the three remaining reaction types Chapter 17, eliminations Chapter 18, rearrangements Chapter 19, oxidation-reduction reactions. This last chapter covers only those oxidation-reduction reactions that could not be conveniently treated in any of the other categories (except for oxidative eliminations). 

Naphthalene undergoes electrophihc substitutions at the a rather than p position. The Hueckel molecular orbital calculations show that all the carbons have the same jt electron density 1.0. This is not in agreement with the theory of organic reactions based on the Coulombic interaction that electrophilic attack occurs on the most negatively charged atom. Fukui [7] proposed the frontier orbital theory for the discrepancy between the theory and the experimental observation. The importance of... 

The mechanistic spectrum shed new light on a familiar textbook example of organic reactions, i.e., electrophilic aromatic substitution (Scheme 9). 

Ideally, those molecules that are involved in the catalytic reaction should be the best characterizers of catalytic sites. Indeed, the path of the development of organic reaction mechanisms is paved with clever examples of stereochemistry and isotopic substitution that reveal the nature of activated complexes and intermediates and allow the unambiguous interpretation of the stereorelations... 

CC3 sykes,p. Some Organic Reaction Pathways (A). Elimination (B). Aromatic Substitution (1975). 

A diverse group of organic reactions catalyzed by montmorillonite has been described and some reviews on this subject have been published.19 Examples of those transformations include addition reactions, such as Michael addition of thiols to y./bunsatu rated carbonyl compounds 20 electrophilic aromatic substitutions,19c nucleophilic substitution of alcohols,21 acetal synthesis196 22 and deprotection,23 cyclizations,19b c isomerizations, and rearrangements.196 24... 

Products of organic reactions, magnetic field and magnetic isotope effects on, 30, 1 Protic and dipolar aprotic solvents, rates of bimolecular substitution reactions in, 5, 173 Protolytic processes in H20-D20 mixtures, 7, 259... 

Effect of Isotope Substitution on Organic Reaction Rates. Nucleonics,... 

Kinetic and mechanistic studies of the reactivity Zn-Oh ( = 1 or 2) species in small molecule analogs of zinc-containing metalloenzymes, 41, 81 Kinetics and spectroscopy of substituted phenylnitrenes, 36, 255 Kinetics, of organic reactions in water and aqueous mixtures, 14, 203 Kinetics, reaction, polarography and, 5, 1... 

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