Organic Chemistry: A Mechanistic Approach

Book Preface

Organic chemistry is a mature branch of science which continues to expand in the sense that new reactions and new compounds continue to be discovered. Some compounds newly isolated from natural sources support life; others, synthesized in the laboratory, are unknown in nature but have led to advances in medicine and other areas of science and technology. A consequence of the huge and increasing number of known organic compounds is that any chemist can have book-knowledge of only a tiny fraction and practical experience of an even smaller number. However, a molecule of an organic compound may generally be seen as a functional group bonded to a hydrocarbon residue and organic chemistry is essentially the chemistry of a relatively small number of functional groups. Consequently, comprehension of organic chemistry as a whole is achievable from knowledge of the characteristic reactions of functional groups and an understanding of how they occur, i.e. their mechanisms.

The Approach of this Book
There are different approaches to the teaching of organic chemistry at university level. In this book, we begin with a review of atomic and molecular structure and then look at factors which determine the shapes of molecules. Next, we cover acid–base (proton transfer) reactions since these are distinctive features of many reactions of organic compounds, especially ones of biological importance including reactions catalysed by enzymes. We then show that all overall reactions of organic compounds belong to one of a relatively small number of classes of reaction types. Moreover, when we introduce the concept of mechanism in organic chemistry, and look at how reactions take place, we see that only a small number of types of elementary steps are involved.

When features common to all organic reactions have been covered, we proceed to look at reactions of individual functional groups. Our approach, based upon a survey of teachers of organic chemistry in over 50 colleges and universities in Japan and guided by nine reviewers from different parts of Europe and North America, is to focus on underlying mechanistic principles as the unifying basis of organic chemistry.

The outcome is a concise non-mathematical text which introduces molecular orbital considerations early on and uses ‘curly arrows’ (as appropriate) to describe mechanisms throughout. The book is not intended to be an encyclopaedic reference text of organic chemistry; it is a learning-and-teaching text and the coverage broadly corresponds to the organic chemistry syllabus of a typical honours degree in chemistry at a British university. However, we include connections to biological sciences wherever they are relevant to emphasize that organic chemistry is the basis of life science. To supplement the core chemistry, we have also included ‘panels’ containing material (sometimes topical) which relate the chemistry to current everyday life and biological phenomena. Consequently, depending on the level to which the subject is to be taught, the book could be appropriate for students of health sciences and technology, as well as premedical students.

Learning from this Book
To assist students, worked examples and exercises are embedded within each chapter; answers to inchapter exercises are provided on the book’s web site, which we describe further below. Each chapter also has a summary together with additional problems at the end. In addition, we include an early section on organic nomenclature, appendices which contain reference data, and fl ow charts encapsulating reactions and interconversions of functional groups, and a comprehensive index.