Organic Chemistry 6th Edition

Book Preface

This Sixth Edition of Organic Chemistry significantly extends the transformation started in the Fifth Edition. Students taking an organic chemistry course have two objectives; the first is to learn organic chemistry, and the second is to establish the intellectual foundation for other molecular science courses. Most often, these other courses involve biochemistry or specialized topics such as materials science. This textbook addresses these two objectives head-on by first presenting mechanistic and synthetic organic chemistry geared toward giving students a fundamental understanding of organic molecules and reactions, as well as their mechanisms and uses in organic synthesis. The text then builds upon the fundamentals by providing an emphasis on bridging concepts that will prepare students for subsequent science courses. Several unique elements including comprehensive end of chapter summaries, a new paradigm for learning mechanisms and a new learning tool we call Organic Chemistry Road Maps have been included to increase the efficiency of student studying and learning.

Making Connections

All the important reaction mechanistic and synthetic details are still found throughout the text, but we have increased the important connections between different reaction mechanisms. The intent is to make the study of organic chemistry a process involving the learning and application of fundamental principles and not an exercise in memorization. Throughout this edition, the uniting concept of nucleophiles reacting with electrophiles is highlighted. Especially helpful is the use of electrostatic potential surface models of reacting molecules. These maps emphasize, in an easily interpreted, color-coded fashion, how the majority of reactions involve areas of higher electron density on one reactant (a nucleophile) interacting with areas of lower electron density on the other reactant (an electrophile)

A Fresh Look at Mechanisms

Starting in Chapter 6, this edition introduces a revolutionary new paradigm for learning organic chemistry mechanisms. Students are introduced to a small set of individual mechanism elements in Chapter 6. The mechanism elements are explained in detail, including when they are appropriate to use. Reaction mechanisms throughout the book are then described as combinations of these individual mechanism elements, which are written in stepwise fashion. This new approach not only simplifies the learning of mechanisms for students, it makes it easier for them to recognize similarities and differences among related reactions. Most important, it makes the prediction of reaction mechanisms simpler, analogous to a multiple choice situation in which the correct mechanism element is chosen from a small menu of choices. Also, to give students more confidence with writing mechanisms, Appendix 10 on Common Mistakes in Arrow Pushing has been added. In addition, many mechanisms (particularly in Chapter 18) have been broken down into more descriptive steps to make it easier for students to understand the concepts involved.

A Fresh Look at Orbitals

An organic chemist’s theoretical framework for understanding electron density within molecules is based on atomic and molecular orbitals. Paradoxically, organic chemistry texts generally provide only passing coverage of orbitals, never revealing their true shapes or full significance. The Sixth Edition is the first organic text to paint a detailed picture of the orbital nature of electron density in Chapter 1 by focusing on the interplay between the two complementary approaches to orbital descriptions, valence bond theory and molecular orbital theory. Chapter 1 provides a comprehensive description of how electronic theory is used by organic chemists to understand structure, bonding, and reactivity. Significantly, students are given easy-to-use guidelines that detail when and how to use electronic theory, even in complex situations, such as molecules described by multiple resonance contributing structures. The inclusion of calculated orbital diagrams side-by-side with the familiar orbital cartoons gives students a greater appreciation for orbital sizes and shapes that are reinforced throughout the book. The intent is to provide students with a strong theoretical foundation that will give them unprecedented insight and intuition into molecular structure and reactivity

Mastering Skills

Mastering organic chemistry requires the development of certain intellectual skills. To this end, eleven How To boxes highlight “survival skills” for organic chemistry students. Topics include, How To Draw Alternative Chair Conformations of Cyclohexanes (Section 2.5), How To Draw Curved Arrows and Push Electrons (Section 1.8), and How to Write Mechanisms for Interconversions of Carboxylic Acid Derivatives (Section 18.4)