Learning Organic Functional Group Chemistry

Regions of electron deficiency Regions of electron excess  

A second strategy is to replace one atom by another close to it in the Periodic Table to reveal analogies and patterns of reactivity. For example, replacing a nitrogen atom by an oxygen atom may reveal analogies between the reactivity of nitriles and carbonyl compounds and between enamines and enols. It may also provide some useful ideas for synthetic methods. 

The 2s and 2p orbitals of carbon may be hybridized to give the tetrahedral sp planar sp- and linear sp arrangements. Carbon may form a- and Tt-bonds to other atoms. Two or more n-bonds may be conjugated. A cyclic conjugated system containing (4/ + 2)ji electrons possesses a particular stability known as aromaticity. 

Functional groups are inter-related by a series of redox and substitutive transformations. The reactions of functional groups may be determined by the electronegativity differences between the component atoms. 

Nucleophiles are electron-rich, sometimes anionic, reagents which participate in reactions at centres of electron deficiency in a molecule. 

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The most effective way to review material often differs from the most effective way to first learn material. This is especially true with organic chemistry. The best way to first leam the subject matter is in little groups, as we have presented it However, the best way to review the material is to look at the big picture. Our summary of the hydrocarbons. Table 21.4, and summary of the organic functional groups, Table 21.5, will be particularly useful in your chapter review. 

Second, organic chemistry is about organization. You ll hear the teachers say it as well as the texts organic chemistry is NOT about memorization. There are hundreds of reactions which have already been organized by different functional groups. If you learn the chemistry behind the reactions and when and why they take place, you ll soon see yourself being able to apply these reactions without memorization. 

The discussion which follows is organized in the following fashion. First a common undergraduate text was used to provide a list of standard or traditional preparations for the major functional groups dealt with herein. Most of these reactions should be familiar because they are the ones learned (or not learned) in the undergraduate course in organic chemistry. Although these methods will be listed and perhaps discussed briefly, the discussion in no way serves as a review of these methods. 

To understand the chemistry of these more complex carbohydrates, we must first learn the principles of carbohydrate structure and reactions, using the simplest monosaccharides as examples. Then we will apply these principles to more complex disaccharides and polysaccharides. The chemistry of carbohydrates applies the chemistry of alcohols, aldehydes, and ketones to these polyfunctional compounds. In general, the chemistry of biomolecules can be predicted by applying the chemistry of simple organic molecules with similar functional groups. 

Like that of alcohols, the chemistry of amines does not always fit neatly into one reaction class, and this can make learning the reactions of amines challenging. Many interesting natural products and widely used drugs are amines, so you also need to know how to introduce this functional group into organic molecules. 

Organic reactions usually take place at the functional group, so learning about the reactivities of functional groups will prepare you to understand many other things about organic chemistry. 

The chemistry of organic and biological molecules is usually controlled by the functional group found in the molecule. Just as members of the same family of the periodic table exhibit similar chemistry, organic molecules with the same functional group exhibit similar chemistry. Although it would be impossible to learn the chemistry of each organic molecule, it is relatively easy to learn the chemistry... 

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