The Field of Organic Chemistry

The first question we might ask is What is organic chemistry, and how did it become a separate branch of chemistry A brief survey of the history of organic chemistry will help us understand how the division of chemicals into organic and inorganic originated and why this division persists today. 

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In 1808 John Dalton proposed his atomic theory, making a major contribution to the understanding of inorganic compounds. Essentially, Dalton s theory postulated that the elements are composed of small, indivisible particles called atoms and that these atoms combine in ratios of small whole numbers to form chemical compounds. 

Although this division into organic and inorganic is useful in organizing the vast subject of chemistry, the division is somewhat arbitrary. For example, a compound that 

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The 20th century brought important advances in the field of organic chemistry. In the first decades of the century, the syntheses of inaeasingly complex molecules were accomplished. Some notable compounds synthesized during that time were a-terpinol (WH. Perkin, 1904), camphor (G. Komppa, 1903), and tropinone (R. Robinson, 1917 Figure 10.3-28). 

Synthetic adhesives have resulted from developments in the field of organic chemistry. Virtually all are obtained from petroleum, natural gas, or coal by-products. 

Because of the great differences in the properties between vinyl polymers and heterochain polymers, copolymerization of a vinyl monomer and a cyclic monomer seems very intersting. Yet, little success has been achieved in the formation of random copolymers because the reactivities are very different between vinyl monomers and cyclic monomers. However, recent progress in the field of organic chemistry has suggested many possibilities especially for the activation of monomers and for the modification of the reactivity of the propagating species. The probability of successful synthesis of random copolymers has thus greatly increased. 

Qualitative and quantitative relations between enthalpy and entropy were observed several times in the 1920 s, and their importance was rightly recognized by some authors. However, some ideas from this early work seem to have been overlooked later, perhaps because they were connected with obsolete theories or because they were developed independently in the fields of organic chemistry, catalysis, and pure physical chemistry. For this reason, a brief historical survey seems appropriate. 

Today, in the field of organic chemistry, increasing attention is being given to Green Chemistry [19], using environmentally safe reagents and, in particular, sol-vent-free procedures. Reactions performed without the use of a solvent can indeed... 

I have included much new material that has come to my attention since the first edition of this book, but with the field of organic chemistry growing as it is, there are undoubtedly syntheses that have eluded me. I would appreciate readers calling attention to these. 

The development of catalytic asymmetric reactions is one of the major areas of research in the field of organic chemistry. So far, a number of chiral catalysts have been reported, and some of them have exhibited a much higher catalytic efficiency than enzymes, which are natural catalysts.111 Most of the synthetic asymmetric catalysts, however, show limited activity in terms of either enantioselectivity or chemical yields. The major difference between synthetic asymmetric catalysts and enzymes is that the former activate only one side of the substrate in an intermolecular reaction, whereas the latter can not only activate both sides of the substrate but can also control the orientation of the substrate. If this kind of synergistic cooperation can be realized in synthetic asymmetric catalysis, the concept will open up a new field in asymmetric synthesis, and a wide range of applications may well ensure. In this review we would like to discuss two types of asymmetric two-center catalysis promoted by complexes showing Lewis acidity and Bronsted basicity and/or Lewis acidity and Lewis basicity.121... 

These methods require that the sample is either a gas or, at least, a volatile substance which can be easily converted into a gas (this explains the utility of mass spectrometry in the field of organic chemistry). In inorganic chemistry it is often more difficult to obtain a gaseous sample, and so other ionization sources have been developed. If the sample is thermally stable, it may be volatilized by depositing it on a filament and heating the filament (thermal ionization mass spectrometry - see below). In restricted cases (e.g., organometallic chemistry), chemical treatment of the sample may give a more volatile sample. 

The facts noted in the four subsections of this chapter suggest that chemists ought to keep an open mind concerning the concept of chemical bonding. Useful as this concept is the field of organic chemistry, it becomes more and more meaningless and inadequate as we move toward inorganic, nonmetallic and, above all, metallic chemistry. 

The continued success of the extended Hiickel method in transition metal chemistry, where it was the method of choice until the mid 1980 s is surely related to the problems of other semiempirical methods in this area of chemistry. While methods like MOP AC [21] or AMI [22] have been extremely productive in the field of organic chemistry, they have found little success in transition metal chemistry. These methods are based in equation 2, similar to 1, but with the very significant difference that the Fock matrix F is computed from the molecular orbitals, in an iterative way, though through an approximate formula. 

Numerous reactions in the field of organic chemistry are known to involve the intermediate formation of ions, though only few ionic equilibria are known. Amines, amides, alkoxides or halide ions are known to act as donors and to produce ionic species 24 26 ... 

This chapter describes a number of examples of kinetic isotope effects on chemical reactions of different types. These examples will be used to illustrate many aspects of the measurement, interpretation, and theoretical calculation of KIE s. Many of the examples are chosen from the field of organic chemistry. Chapter 11 deals with biochemistry, more specifically with enzyme chemistry. 

Stereochemistry. The field of organic chemistry devoted, to three-dimensional spatial arrangements of molecules. Deals with stereoisomers, compounds having identical chemical formulas but different spatial arrangement of their atoms, such as geometric (cis/trans) isomers and optical (isotactic, atactic, and syndiotactic) isomers. 

Over the years, many people contributed to the development of the field of organic chemistry. To better understand how this science provides so many useful items for our daily use, it is necessary to be familiar with some of the nomenclature of organic chemistry. There are two basic types of hydrocarbon substances, namely, aliphatic and aromatic. There are three basic types of aliphatic hydrocarbon molecules defined by the number of bonds involved in straight linear-chained molecules. If the basic structure of a hydrocarbon molecule is a ring instead of a straight chain, they are known as aromatic hydrocarbons, typified by the benzene ring. 

For a long time metal carbenes have been either classified as Fischer- or Schrock carbenes, depending on the oxidation state of the metal. Since the introduction of N-heterocycHc carbene complexes this classification needs to be extended because of the very different electronic character of these ligands. Carbenes—molecules with a neutral dicoordinate carbon atom—play an important role in all fields of chemistry today. The first examples in the field of organic chemistry were published by Doering and Hoffmann in the 1950s [1], while Fischer and Maasbol introduced them to organometallic chemists about ten years later [2,3]. But it took another 25 years until the first carbenes could be isolated [4-8]. 

In the field of organic chemistry, new synthetic strategies and methodologies are developed at an astonishing rate to access a diverse range of molecules. 

Many other applications of electrochemical methods for chemical characterization are presented in the following chapters. The state of utilization is such that for many research groups in the fields of organic chemistry and inorganic chemistry, electrochemistry has become a characterization tool as essential as infrared and NMR spectroscopy. This is quickly becoming true for several areas of biochemistry, especially enzymology. 

N. M. Kizhner, Studies in the Field of Organic Chemistry, p. 482. Akad. Nauk SSSR, Moscow, Leningrad, 1937 (in Russian). 

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