Organic chemistry, origins

Lazcano A, Bada JL. The 1953 Stalney L. Miller experiment fifty years of prebiotic organic chemistry. Origins Life Evol Biosphere 2003 33 235-42. 

Organic chemistry originally referred to the study of chemicals that were derived from nature, i.e. an organic source. It was believed that these chemicals were different from those that were mineral in origin, i.e. the inorganic chemicals. It was proposed that this difference was so fundamental that it would be impossible to make an organic chemical from components that were derived only from mineral sources, because the latter did not contain the essential vital force that was required to form organic compounds. 

Lazcano, A. Bada, J. L. The 1953 Stanley L. Miller Experiment Fifty Years of Prebiotic Organic Chemistry. Origins of Life Evol. Biosphere 2003, 33,235-242. 

Recrystallisation. The process of purification by recrystallisation is undoubtedly the most frequent operation in practical organic chemistry, and it is one which, when cleanly and efficiently performed, should give great pleasure to the chemist, particularly if the original crude material is in a very impure and filthy condition. Yet no operation is carried out so badly, wastefully (and thoughtlessly) by students in general, not only by elementary students, but often by research students of several years experience. The student who intends later to do advanced work must master the process, for unless he can choose a suitable solvent and then successfully recrystallise often minute quantities of material, he will frequently find his work completely arrested. 

Take the Final Function Value of TINKER as the steric energy for this calculation. Compare the results with each other and with a standard value from a good elementar-y organic chemistry text (e.g., Ege, 1994). Calculate for the reaction cis trans and compare it with a standard text and with Kistiakowsky s original value. Kistiakowsky s original work was carried out at 355 K, but the temperature difference between 298 K and 355 K cancels for this isomerization. 

Chemisches Zentrallblatt. This periodical, published by the Deutsche Chemische Gesellschaft to 1945, originated in 1830 as the Phar-maceutisches Zentrallblatt, the name was changed in 1850 to Chemisches-Pharmaceutisches Centrallblatt, again in 1856 to Chemisches Centrall-blatt, and in 1907 to Chemisches Zentrallblatt. Collective indexes are available from 1870. The abstracts, particularly for organic chemistry, are very detailed to 1939. 

In compiling this book, the author has drawn freely from all sources of information available to him—research notes, original memoirs in scientific journals, reference works on organic chemistry, the numerous text books on practical organic chemistry, and pamphlets of manufac turers of specialised apparatus. Whilst individual acknowledgement cannot obviously be made—in many cases the original source has been lost track of—it is a duty and a pleasure to place on record the debt the writer owes to all these sources. Mention must, however, be made of Organic Syntheses, to which the reader is referred for further details of many of the preparations described in the text. 

One of the most original and significant ideas in organic chemistry was the suggestion by Hans Meerwein that carbocations (as we now call all the positive ions of carbon compounds) might be intermediates in the course of reactions that start from nonionic reactants and lead to nonionic covalent products. 

Hydrocarbons are divided into two mam classes aliphatic and aromatic This classifi cation dates from the nineteenth century when organic chemistry was devoted almost entirely to the study of materials from natural sources and terms were coined that reflected a substance s origin Two sources were fats and oils and the word aliphatic was derived from the Greek word aleiphar meaning ( fat ) Aromatic hydrocarbons irre spective of their own odor were typically obtained by chemical treatment of pleasant smelling plant extracts... 

A second type of structural information can be deduced from the hyperfine splitting in EPR spectra. The origin of this splitting is closely related to the factors that cause spin-spin splitting in proton NMR spectra. Certain nuclei have a magnetic moment. Those which are of particular interest in organic chemistry include H, " N, F, and P. 

Figures 1-3 and Tables 1-3 were originally published in the indicated volumes of the Journal of Organic Chemistry. The American Chemical Society has kindly granted permission for reproduction. The author is indebted to Professor H. Wynberg and Professor D. J. Gerritsen for encouragement to write this chapter.

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