Organic chemistry

“ So the organic body is built on a chain or frame-work or skeleton of carbon atoms, about which are grouped the atoms of hydrogen, oxygen, and nitrogen, or radicle compounds thereof.
It is not possible here to even name some of the more eminent workers who for a quarter of a century have contributed to our knowledge of organic chemistry. This branch of chemistry has been the vogue, and has been pushed almost to the limit of possibility since 1875. ”

“ The chemist might go on continually manufacturing hydrogen and oxygen, carbon dioxide, ammonia. But he was never to hope to make alcohol, sugar, urea, any of the multitudinous substances called organic. And now all this folly of forbidding is at an end. The organic bodies are manufactured by man. The inorganic and the organic are no more regarded as clearly distinguishable. Even the chemistry books by their very titles recognise and proclaim this fact. We have no longer works on organic chemistry. We have volumes on the chemistry of carbon compounds. ”

“ In organic as in inorganic chemistry, atoms are bound together by chemical affinity, though it was formerly supposed that an additional or vital force was instrumental in forming organic compounds. For this reason none of these substances, it was thought, could be built up in the laboratory, although many had been analyzed. In 1828 the first organic compound, urea, was artificially prepared, and since then thousands have been synthesized. They are not necessarily manufactured from organic products, but can be made from mineral matter. ”

“ The fundamental task of inorganic chemistry is still connected with the classification of elements and compounds. The investigation of the classification of carbon compounds forms the field of organic chemistry; while general or physical chemistry deals with the laws of reaction, and the influence of various forms of energy in furthering or hindering chemical change. ”

“ The mysteries of organic chemistry are great, and the differences between its processes or reactions as they are carried out in the organism and in the laboratory are many421. The actions, catalytic and other, which go on in the living cell are of extraordinary complexity. But the contention that they are different in kind from what we term ordinary chemical operations, or that in the production of single asymmetric compounds there is actually to be witnessed, as Pasteur maintained, a “prerogative of life,” would seem to be no longer safely tenable. ”

“ For a similar reason the study of inorganic chemistry naturally precedes the study of organic chemistry, because inorganic compounds are much simpler and therefore more easily analysed and investigated than organic compounds. ”

“ But that is a matter of inorganic chemistry, you say. Very true. But I dare to assert, standing here on my two feet, that in the organic I can duplicate whatever occurs in the inorganic.
“Here!” He held a test-tube between me and the light, and I noted the cloudy or muddy liquid it contained. He emptied the contents of another test-tube into it, and almost instantly it became clear and sparkling.
“Or here!” With quick, nervous movements among his array of test-tubes, he turned a white solution to a wine color, and a light yellow solution to a dark brown. ”

“ Compounds containing carbon enter into all the products of a living cell. For this reason the chemistry of carbon compounds came to be known as organic chemistry. This should not be taken as a definition, however, without limitations. Many of the compounds containing carbon are not known to enter into living tissue in any way, and their connection with it is very remote and not essential. On the other hand, it should be remembered that many organic compounds, and those even of most importance, contain some other element,—nitrogen, for example,—as the significant one. ”

“ Almost the whole of the substances which have been called organic contain carbon, and are probably held together by the carbon atoms, so that many chemists are now inclined to abandon the name Organic Chemistry, and substitute the name Chemistry of the Carbon Compounds. ”

“ In the formation of formic acid from carbonic oxide we observe an example of the synthesis of organic compounds, such as are now very numerous, and are treated of in detail in works on organic chemistry. ”

“ Although there can be no doubt that this doctrine greatly stimulated the pursuit of organic chemistry, it was gradually perceived that to regard inorganic and organic chemistry as the chemistry respectively of the simple and of the compound radicals was an imperfect and misleading conception of the true relations of the two main divisions of the science. Facts showed that the properties of a substance depend more on the arrangement of its atoms than on their nature. ”

“ The subject of Organic Chemistry is that to which, at the present day, the eyes of all thinking members of the profession are directed, and upon which their hope of progress mainly depends,—the relations of chemical action to the functions of organized matter, the application of chemistry to physiology and pathology, are to be treated of as fully as present knowledge extends. ”

“ It is not many years ago—and you must recollect that Organic Chemistry is a young science, not above a couple of generations old, you must not expect too much of it,—it is not many years ago since it was said to be perfectly impossible to fabricate any organic compound ”

“ By means of the electric furnace, Moissan, in France, has succeeded in uniting carbon with many of the metallic elements, and thus opened the path for new achievements in passing directly from inorganic to organic compounds.
202 The progress of chemical synthesis has already blotted out the old distinction between inorganic and organic chemistry, and we can no longer say of organic bodies that they are the products of living cells. Organic bodies are those which contain a carbon or other elementary skeleton, to which are attached the elements or groups of elements forming the complete body. ”

“ By the impulse given to organic chemistry by Liebig, our knowledge of the almost infinite variety of substances, in physical character exceedingly dissimilar, which result from the combination of oxygen, hydrogen, and carbon, in varying proportions, has been largely increased. ”

“ In the classification of this science, it has been divided into inorganic chemistry, relating to metals, minerals and bodies not associated with organic life, and organic chemistry, which was formerly limited to matter associated with or the result of growth or life processes, but which is now extended to the broader field of all carbon compounds. ”

“ The practical side of organic chemistry should never be lost sight of for a moment, and under no condition should the course be allowed to deteriorate into one of mere picturing of structural formulæ on the blackboard. All chemical formulas are merely compact forms of expression of what we know about chemical compounds. There are, no doubt, many facts about chemical compounds which their accepted formulas do not express at all, and the wise teacher should lead the student to see this. ”

“ The properties of matter are so distributed among the elements that three of them—Oxygen, Hydrogen, and Carbon—possess an ensemble of unique characteristics. The number of reactions in inorganic chemistry are relatively few, but in organic chemistry—in the chemistry of these three elements the number of different compounds is practically unlimited. ”

“ Chemistry divides creation into two distinct parts,—organic nature, and inorganic nature. Organic nature, comprising as it does all animal and vegetable creations which show an organization more or less perfect,—or, to be more exact, a greater or lesser motive power, which gives more or less sensibility,—is, undoubtedly, the more important part of our earth. Now, analysis has reduced all the products of this nature to four simple substances, namely: three gases, nitrogen, hydrogen, and oxygen, and another simple substance, non-metallic and solid, carbon. ”

“ When he began his active career it was generally believed that, although some instances of the synthetical production of organic substances had been observed, on the whole organic chemistry must remain an analytical science and could not become a constructive one, because the formation of the substances with which it deals required the intervention of vital activity in some shape. ”

“ The influence of special groupings in retarding chemical change is apparently well established, but no comprehensive theory of the subject is yet possible. Until such a theory is forthcoming a dynamical theory of stereo-chemistry is incomplete.
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CHAPTER X
Organic Synthesis: Condensation: The Synthesis of Vital Products In its widest sense, the term “synthesis,” as used in organic chemistry, means the building-up of carbon compounds, either from their constituent elements or from groups of differently constituted molecules. ”

“ Until the last few years, however, chemistry has been mainly occupied with the production of what were called inorganic compounds, and with the analysis or breaking up of organic substances. It could not produce any of the myriad combinations which were constantly formed by the simplest animal or vegetable structures. By many, therefore, these organic bodies were looked upon as things apart, not to be put together by the unhallowed hand of the chemist, only to be brought into being when touched by the sacred Promethean flame of life. ”

“ A great many natural organic compounds have been made artificially since that time, and some of them, such as artificial alizarin, indigo, oil of wintergreen, and vanillin, have more or less fully replaced the natural products. The preparation of a vast number of compounds not known in nature, many of which are of practical importance as medicines, dyes, explosives, etc., has been another great achievement of organic chemistry. ”

“ The synthesis of other so-called organic compounds followed, and at present it is known that the same chemical laws apply to all substances whether formed in the living organism or prepared in the laboratory from inorganic constituents. ”

“ Hence, reactions between organic compounds, even when they are in solution, proceed very slowly unless carried on at high temperatures, under increased pressure, or under the influence of some catalytic agent. Even under the stimulation of these reaction-accelerating agencies, most chemical changes in organic compounds when carried on in the laboratory, require several hours or even days and sometimes weeks, for their completion. But when similar reactions take place in living organisms, they proceed with velocities which resemble those of inorganic compounds in the laboratory. ”

“ As soon as the four principal elements, carbon, oxygen, hydrogen, and nitrogen, that make up the living body, have entered the world of living matter, their activities and possible combinations enormously increase; they enter into new relations with [Pg 78] one another and form compounds of great variety and complexity, characterized by the instability which life requires. The organic compounds are vastly more sensitive to light and heat and air than are the same elements in the inorganic world. What has happened to them? Chemistry cannot tell us. ”

“ Not only is the quantity of valuable matters existing in the soluble state materially increased, whereby the dung is enabled to act with greater rapidity, but, owing to evaporation and the escape of carbonic acid, produced by the decomposition of the organic substances, the proportion of those constituents which are most important to the plant is increased. ”

“ C – is one of the most difficult to loosen.
The conception of metamerism, or isomerism in restricted sense, has been of the highest value for the development of our notions concerning molecular structure, i.e. the conception as to the order in which the atoms composing a molecule are linked together. In this article we shall confine ourselves to the fatty compounds, from which the fundamental notions were first obtained; reference may be made to the article Chemistry: Organic, for the general structural relations of organic compounds, both fatty and aromatic. ”

“ But it may be convenient to treat the subject of the artificial production of this group of bodies rather more comprehensively and as a sub-section of this chapter on organic synthesis, since their formation by such means constitutes a phase in the development of chemistry, and has undoubtedly exercised a profound influence on scientific thought and on philosophical and even theological doctrine. During the past fifty or sixty years the chemist has been enabled to form the active principles or characteristic products of many plants and animals. ”

“ Moreover, the important fact must be fully recognized that in living beings we have to do with no new elementary forms of matter. Precisely the same atoms which build up the inorganic fabric, compose the organic. In the early days of chemistry, indeed, it was supposed that the complicated molecules which life produced were beyond the reach of simple chemical law. But as more and more complex molecules have been, one after another, produced, chemistry has become re-assured, and now doubts not her ability to produce them all. ”

“ This doctrine may be illustrated Modern Pythagorisms in chemistry. by facts familiar to chemists, who, in like manner, attach significant numbers to the names of things. Taking hydrogen as unity, 6 belongs to carbon, 8 to oxygen, 16 to sulphur. Carrying those principles out, there is no substance, elementary or compound, inorganic or organic, to which an expressive number does not belong. Nay, even an archetypal form, as of man or any other such composite structure, may thus possess a typical number, the sum of the numbers of its constituent parts. ”