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[交流] Introduction to Organic Chemistry

Introduction to Organic Chemistry
1. Sources of Organic Compounds
The major sources of organic chemicals are coal, petroleum, and agricultural products. Both coal and petroleum were formed through the geologic processes of changing animal and plant remains into carbon-containing residues. About one-third of all organic chemicals are derived from coal and about one-half from the petroleum industry.
有机化学简介
1.有机化合物的起源
有机化合物的主要来源是煤、石油和农产品。煤和石油都是通过地质过程将动物和植物残余物转化为含碳残渣。大约1/3有机化学品由煤形成，1/2由石油工业形成。

2. The Methods and Objectives of Organic Chemistry
Because of the tremendous number of organic compounds known, and of the many more being synthesized daily, the study of organic chemistry is not the study of individual compounds, it is the study of groups or families of compounds all closely related to each other. Obviously, the former approach would be prohibitive. Once the structural relationships of certain typical members of a particular group or family of compounds are understood, these structural features are understood for any one of the many members of the family, even though some may not be known compounds. For each group or family of compounds often called homologous series of compounds, structural features are important. In studying organic chemistry, it is not enough to know the identities of the elements and how many atoms of each element are present in a given molecule. More importantly, the order in which these atoms are linked together to form the molecule must also be known. Once the identities of the elements and the number of atoms present in each of these elements have been established, structural studies are quite important. They require considerable effort and ingenuity on the part of the organic chemist.
2.有机化学的方法和目标
因为已知的有机化合物的数目极大，而且还在逐日合成更多的品种，所以有机化学不是研究单个的化合物，而是把彼此密切关联的化合物按类或族来研究。很明显，以前的方法并不可取。一旦掌握了某类或族化合物中某些典型化合物的结构关系，也就掌握了该族化合物中任一化合物甚至包括一些尚未发现化合物的结构特征。对于被称为同系物的每一族或类化合物来说，结构特点非常重要。在研究有机化学时，只知道某一分子中含有哪些元素以及各元素的原子数还是不够的。一旦掌握了元素的种类以及这些元素中每一元素的原子数，那么结构研究就非常重要。这些研究需要有机化学家相当大的努力和智慧。
Another important phase of the study of organic chemistry is communication, or exchange of information, among organic chemists. This requires the acquisition of adequate vocabulary and terminology so that any one of the more than a million known compounds, or any one of the yet unsynthesized compounds, can be discussed intelligently on an individual basis. This requires a highly systematized method of naming organic compounds. This science of nomenclature has received considerable attention during the development of organic chemistry, and it will constitute a second important topic for consideration in connection with each homologous series of compounds to be studied.
研究有机化学另一个重要的方面是有机化学家有关有机化学的交流或信息交换。这就需要熟悉足够的词汇和术语，以便能对百万种以上已知的以及目前尚未合成的化合物中的任一化合物，逐个进行充分的讨论，给有机化合物命名需要高度系统化的方法。在有机化学的发展过程中，科学命名法受到了重大的关注，它将构成将要研究的与同系列化合物相关的一些问题当中另一个重要问题。

A third important topic for consideration in connection with each homologous series of compounds is procurement. Many organic compounds, as pointed out earlier, are naturally occurring. Many others, however, are not found in nature, and must be synthesized or prepared from compounds which can be obtained from natural sources. The term "synthesis" means building up of a molecule from smaller units. It is more often used, however, to mean the chemical process of changing or converting an available compound into the desired compound, either in the laboratory or on a larger scale, as in a manufacturing plant. This general topic can be described as "Methods of Synthesis"
与化合物同系列的相关的另一个重要的方面是如何合成。很多有机化合物，如前面指出的，是自然形成的。然而许多其它化合物，不能在大自然中找到，必须用以自然中得到的化合物来合成。合成是用更小的单元组建成分子。然而，它通常多被用来表达将一种可得到的化合物转变或转换为一种不可得到的化合物的化学过程，这个过程要么发生在实验室，要么发生在一个更大的规模中，比如制造工厂。一般合成被描述为合成和方法。
3. Identification of Unknown Organic Compounds
The chemistry of biological systems is very complicated and the organic compounds present are numerous and constitute complex mixtures. Consequently, isolation of a pure chemical species from any one of the major sources of organic matter requires elaborate and painstaking isolation procedures. Therefore, a major portion of the effort of organic chemists over the years has been devoted to improving methods for isolation and purification of organic compounds.
3.未知有机化合物的鉴别
生物化学系统是非常复杂的，并且现有的有机化合物众多且组成复杂的混合物。因此
从任何一个有机物质的主要来源中分离一个纯粹的化学物质需要一个详尽精细的程序。
因此，有机化学家经过多年努力致力于有机化合物分离和提纯的改进。

In summary, the following four steps are required in order to completely identify any organic
compound isolated for the first time from a natural source or produced for the first time in
the laboratory
( 1 ) Isolation of the compound from the mixture of organic or inorganic compounds among
which it may be foundfollowed by application of appropriate criteria of purity.
(2)Establishment of its empirical and molecular formulas by use of appropriate methods of
qualitative analysis, quantitative analysis and molecular weight determination
(3)Proposal of a structural formula physical examination of the compound as the result of
appropriate chemical and
(4)Synthesis of the compound by an unambiguous method as confirmation of the proposed
structural formula
总之，需要经过以下四个步骤才能完整地鉴定任何首次从自然资源中分离出来或首次在实验室中合成的有机化合物。
（1）将这种物质从发现它的有机或无机混合物中分离出来，然后应用适当的纯度标准。
（2）通过适当的定性定量分析方法来确立结构式和经验式。
（3）对该物质进行适当的化学和物理检测，根据所得出的结果提出一个结构式。
（4）用一个清楚的方法合成该化合物来证明你所提出的结构式。

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