Some Important Classes of Organic Reactions

Organic reactions are classified according to the chemical process involved. Three important classes are addition, elimination, and substitution reactions. 

The three classes of organic reactions we discuss here can be identified by comparing the number of bonds to C in reactants and products  

An addition reaction occurs when an unsaturated reactant becomes a saturated product y 

Note the C atoms are bonded to more atoms in the product than in the reactant. 

The C=C and C C bonds and the C=0 bond commonly undergo addition reactions. In each case, the tt bond breaks, leaving the a bond intact. In the product, the two C atoms (or C and O) form two additional a bonds. In the following addition reaction, H and Cl from HCl add to the double bond in ethylene  

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Some Important Classes of Organic Reactions Properties and Reactivities of Common Functional Groups... 

A list of examples in this section is not exhaustive rather, they have been chosen to illustrate the different approaches used for immobilization of the catalysts for important classes of organic reactions, namely hydrogenation, oxidation, and coupling reactions. Due to the major industrial importance of olefin polymerization (see Chapter 9.1), and although the objectives of immobilization of polymerization catalysts are rather different from the other examples, some references to this will also be given here. 

The methods of preparation of some of the more important derivatives of a number of classes of organic compounds are described in the various Sections dealing with their reactions and characterisation. These Sections conclude with tables incorporating the melting points and boiling points of the compounds themselves, and also the melting points of selected derivatives. For convenience, the references to the various tables are collected below. 

The intermediates formed in AOPs sometimes are more toxic than the parent compounds and are required to be decomposed completely using either combination of AOPs or combination of AOP and some other treatment methods such as adsorption and biodegradation. Carbonyl compounds, particularly aldehydes, are quite toxic, and some of the secondary compounds formed from aldehydes, especially peroxyacylnitrates are more dangerous than the parent compounds. Organic peroxy radical (ROj) reactions are of significance because they represent an important class of intermediates formed in the oxidation process of hydrocarbons (15). Intermediates such as ethers and alcohols have enhanced reactivity toward hydroxyl radical. The rate constant of oxidation of these compounds is of similar order of magnitude as of the alkanes. 

The condensed phosphates or polyphosphates are another important class of inorganic phosphates. In these compounds, two or more phosphate groups bond together via P - O - P bonds to form chains or in some cases cyclic species. In soils and waters polyphosphates generally account for only a small part of the total P content. However, these species are very reactive and in many places they are responsible for anthropogenic pollution of natural water, for instance, by detergents. The polyphosphates are formed also in reactions between orthophosphates of mineral fertilizers and soil organic matter and can be leached to surface waters (Kudeyarova and Bashkin, 1984 Kudeyarova, 1996). 

The Ugi reaction is an easily performed one-pot reaction that is applicable to the synthesis of many distinct types (42a-i) of organic compounds, mostly in good to excellent yields. Some of the products (42a-i) represent important classes of synthetic targets, while others are useful as intermediates for the preparation of a variety of nitrogen compounds. 

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