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he Greek word stereos means\solid, \and stereochemistry refers to chemistry in three dimensions. The foundations of organic stereochemistry were laid by Jacobus van't Hoff* and Joseph Achille Le Bel in 1874. Independently of each other, van't Hoff and Le Bel proposed that the four bonds to carbon were directed toward the cor- ners of a tetrahedron. One consequence of a tetrahedral arrangement of bonds to carbon
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H ydrocarbons that contain carbon-carbon triple bond are called alkynes. Non- cyclic alkynes have the molecular formula C, H2n-2. Acetylene (HCCH) is th simplest alkyne. We call compounds that have their triple bond at the end of a carbon chain(RC=CH) monosubstituted, or terminal, alkynes. Disubstituted alkynes (RCCR') are said to have internal triple bonds. You will see in this chapter that a car- bon-carbon triple bond is a functional group, reacting with many of the same reagents
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ntil the second half of the twentieth century, the structure of a substance-a newly discovered natural product, for example-was determined using information obtained from chemical reactions. This information included the identification of functional groups by chemical tests, along with the results of experiments in which the substance was broken down into smaller, more readily identifiable fragments. Typical of this approach is the demonstration of the presence of a double bond in an alkene by cat- nd subsequent
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n contrast to alcohols with their rich chemical reactivity, ethers (compounds contain- ing a C-0-C unit) undergo relatively few chemical reactions. As you saw wher we discussed Grignard reagents in Chapter 14 and lithium aluminum hydride reduc- tions in Chapter 15, this lack of reactivity of ethers makes them valuable as solvents in a number of synthetically important transformatio. In the present chapter you will learn
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arboxylic acids, compounds of the type RCOH, constitute one of the most fre- quently encountered classes of organic compounds Countless natural products are carboxylic acids or are derived from them. Some carboxylic acids, such as acetic acid, have been known for centuries. Others, such as the prostaglandins, which are pow erful regulators of numerous biological processes remained unknown until relatively
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he value of alkyl halides as starting materials for the preparation of variety of organic functional groups has been stressed many times. In our earlier discussions, we noted that aryl halides are normally much less reactive than alkyl halides in reactions that involve carbon-halogen bond cleavage. In the present chapter you will see that aryl halides can exhibit their own patterns of chemical reactivity, and that these reac
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he major classes of organic compounds common to living systems are lipids, pro- teins, nucleic acids, and carbohydrates. Carbohydrates are very familiar to us- we call many of them\sugars.\ They make up a substantial portion of the food we eat and provide most of the energy that keeps the human engine running. Carbohy- drates are structural components of the walls of plant cells and the wood of trees. Genetic
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he relationship between structure and function reaches its ultimate expression in the chemistry of amino acids, peptides, and protein Amino acids are carboxylic acids that contain an amine function. Under cer- tain conditions the amine group of one molecule and the carboxyl group of a second can react, uniting the two amino acids by an amide bond. Amide(peptide)bond
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Welcome to the wonderful new world of e-Text! With its Acrobat 4.0 software shell, e-Text links page files of your textbook and study guide with each other, along with other valuable digital and online resources, to create a non-linear learning experience that's fast, effective and fun
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1.1 The element carbon has atomic number 6, and so it has a total of six electrons. Two of these elec- tr rons are in the Is level. The four electrons in the 2s and 2p levels (the valence shell) are the valence electrons. Carbon has four valence electrons 1.2 Electron configurations of elements are derived by applying the following principles:
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