Mechanistic chemistry, philosophy

Labelling techniques have been used extensively to determine biogenetic paths and to the extent that determining stoichiometry resides in the province of mechanistic chemistry these techniques are covered. The philosophy of their use in this context is very simple and we shall discuss below some more sophisticated examples of labelling. 

This book contains what I call an interlude on the logic, the psychology, and the serendipity of scientific discoveries. Readers may wonder what the correlation is between that short Chapter 9 and diazo chemistry. The specific reason for including it was to elucidate the dediazoniation mechanism of aromatic diazonium ions, but I expanded this mechanistic discussion (Sec. 8.3) in the interlude by including general aspects originating in the philosophy of science as developed by Karl Popper and Thomas S. Kuhn, ideas which, in my opinion, should be better known by all scientists working in chemical research. 

But in spite of Theosophical vitalism (to which I shall return below) and the Theosophical attack on mechanistic science and philosophy, the atomic theory Besant and Leadbeater developed in Occult Chemistry and elsewhere was in many ways a mechanical theory involving interactions of ever-more-rarified particles and their vibrations. It adapted many assumptions of Victorian ether mechanics. 

History of physical organic chemistry is essentially the history of new ideas, philosophies, and concepts in organic chemistry. New instrumentations have played an essential role in the mechanistic study. Organic reaction theory and concept of structure-reactivity relationship were obtained through kinetic measurements, whose precision depended on the development of instrument. Development of NMR technique resulted in evolution of carbocation chemistry. Picosecond and femtosecond spectroscopy allowed us to elucidate kinetic behavior of unstable intermediates and even of transition states (TSs) of chemical reactions. 

The premise of this book is based on the presumption that introductory organic chemistry entails very little memorization. As presented in the chapters contained herein, this presumption is valid provided the student adheres to the philosophy that the study of organic chemistry can be reduced to the study of interactions between organic acids and bases. At this point, use of the principles presented in this book, in conjunction with more detailed coursework, allows students a broader understanding of organic chemistry reactions as described using combinations of fundamental organic mechanistic subtypes. 

Hitherto historians of science have not paid much attention to Boerhaave s religious views and their influence on his natural philosophy. They have mainly emphasised Boerhaave s mechanistic approach to investigating nature and, concerning chemistry, they have praised him for being one of the first to... 

This textbook is not a physical organic chemistry textbook The sole purpose of this textbook is to teach students how to come up with reasonable mechanisms for reactions that they have never seen before. As most chemists know, it is usually possible to draw more than one reasonable mechanism for any given reaction. For example, both an Sn2 and a single electron transfer mechanism can be drawn for many substitution reactions, and either a one-step concerted or a two-step radical mechanism can be drawn for [2 + 2] photocycloadditions. In cases like these, my philosophy is that the student should develop a good command of simple and generally sufficient reaction mechanisms before learning the modifications that are necessitated by detailed mechanistic analysis. I try to teach students how to draw reasonable mechanisms by themselves, not to teach them the right mechanisms for various reactions. 

David Vander Jagt (1942-) received his doctor of philosophy (PhD) in 1967 in synthetic/mechanistic organic chemistry at Purdue University (West Lafayette, Indiana), in the laboratory of the Nobel Laureate H. C. Brown. After Purdue, he took a post-doctoral position at Northwestern University (Chicago, Illinois) in the laboratory of M. L. Bender in bioorganic chemistry/enzymology (1967-1969). When the opportunity came for a joint appointment in the Department of Biochemistry,... 

Yet chemistry could have become a rich source of inspiration and metaphor for everyone interested in the puzzles and dilemmas of human existence. In the chemical philosophies that flourished in the sixteenth and early seventeenth centuries, it was precisely that these theories, now seemingly so arcane and indeed occult, can be considered the first proto-scientific theories of everything . This aspect of Renaissance science, which drew in particular on the ideas of the Swiss alchemist and physician Paracelsus and left its mark on the notion of science developed by Francis Bacon, has been discussed by the American historian of science Allen Debus (1978). It came sometimes into explicit conflict with the mechanistic view of science initiated by Rene Descartes and his followers, and which of course ultimately triumphed in the form of the deterministic mechanics of Isaac Newton. 

Physical organic chemistry, as a sub-discipline, embodied such a duality. In the hands of leaders such as J.D. Roberts or J.A. Berson, it synthesized the molecules it needed for physical measurements. A contemporary survey of the mechanistic role of the physical organic philosophy is available (Hine I960). 

A central theme of our approach is to emphasize the relationship between structure and reactivity. This is why we choose an organization that combines the most useful features of a functional group approach with one based on reaction mechanisms. Our philosophy is to emphasize mechanisms and fundamental principles, while giving students the anchor points of functional groups to apply their mechanistic knowledge and intuition. The structural aspects of our approach show students what organic chemistry is. Mechanistic aspects of our approach show students how it works. And wherever an opportunity arises, we show them what it does in living systems and the physical world around us. 

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