Organic Chemistry

Thomas N. Sorrell
The University of North Carolina at Chapel Hill

PREFACE

Only after I had taught Introductory Biochemistry two or three times did I began to be dissatisfied with the way that Organic Chemistry was being presented at the introductory level. The functional group approach, long the mainstay for presenting vast amounts of information about organic substances, seemed to work for those who wished to continue studying chemistry. But many of the students whose interests leaned toward biology never seemed to care much for organic chemistry, and their apparent frustration with chemical principles in the subsequent biochemistry course made it even more difficult to convince them that understanding the reactions of biomolecules as organic molecules was a worthwhile endeavor.

In thinking about how reactions in nature could be integrated with modern synthetic chemistry, I came to see that another approach was required, so I decided to undertake the writing of a textbook that would differ from others in two ways. First, the reactions of organic molecules would be organized and presented by the mechanism of the transformation. Second, the reactions of metabolic and biosynthetic processes would be integrated with the reactions found in most other texts.

So, a snow-dusted New Year's Eve several years ago found me driving across the russet and sienna plateaus of New Mexico at dusk, dictating into a small recorder all that I could remember about some now-forgotten series of organic reactions, just as I had been doing for the three previous days since I had left the East coast. The trip across the winter-bleak continent, originally to help my friend Don settle in Berkeley for a sabbatical leave, had instead, through a series of unforeseen circumstances, become a solitary adventure that I decided to put to use to initiate the writing of this text. Bruce, my publisher, had jokingly said that we should call the book Organic Chemistry on the Road. But unlike Jack Kerouac, who allegedly pounded out his classic narrative onto a single roll of teletype paper over a mad, three-week period, it has taken me years of writing and working the manuscript to produce a usable book from all of the tapes that I eventually dictated. Carol Wilson deserves a heartfelt thanks for transcribing those tapes into text files that could be edited.

ORGANIZATION

For those who have taught organic chemistry before, the organization of this book may appear quite unorthodox. But if you take some time to look at it, you will find almost all of the standard topics of other books are here, albeit in different places. An overview of the development of organic chemistry is presented in the first chapter as an introduction, with the last section of Chapter 1 providing a detailed preview of how this book is organized. Coverage of the science begins in Chapter 2 with a detailed treatment of nomenclature. I have used a version of this approach, which I learned from Jim Collman, every time I have taught organic chemistry. I find that students learn nomenclature quickly (usually within a week) and then they know what I am talking about when I mention any type of compound throughout the remainder of the course. Notice, too, that the emphasis is put on interpreting names, not on naming compounds, and the rationale for this is discussed in the second chapter.

The content of the next several chapters is fairly standard, but the order of topics is not. For those who are wondering chemistry majors using this text will learn enough reactions because biological reactions and applications have been integrated, I point out specifically the discussions of the Mitsunobu reaction (Chapter 7), the Swern oxidation (Chapter 8), metal-catalyzed epoxidation reactions (Chapter 10), tributyltin hydride mediated radical cyclization reactions (Chapter 11), and the Suzuki reaction (Chapter 13), all topics that deserve to be mentioned in an up-to-date course.

A presentation of chemical synthesis does not occur until Chapter 13, and I know that this will seem too late for some. The same can be said about the coverage of spectroscopy. I believe that an important question is, "what have students learned by the end of the course?" The chemistry majors in the class will undoubtedly learn more about synthesis and spectroscopy later; the others will probably not need to know even what is presented here. Whether students have been doing synthesis or spectroscopy problems for two or three additional chapters by the time the course ends is probably irrelevant, as long as they have been exposed to the fundamental aspects of these topics, which they will have been.

Chapter 16 on Asymmetric Reactions and Synthesis is a unique contribution, although several of the topics are standard fare in presentations about stereochemistry in other books. But because enantioselective synthesis is such an important area of research in the field of organic chemistry, an entire chapter on the topic seems appropriate. The same is true for Chapter 26, which describes the work being done in the field of host-guest chemistry. Chapters in the last third of the text cover much of the chemistry of carbonyl compounds that is normally presented in a typical organic chemistry course, but the biological aspects of this chemistry are woven through the discussions, as already mentioned.

EXERCISES

Anyone who has taken Organic Chemistry knows that he best way to learn the subject is to solve problems, and the text has hundreds, covering a range of difficulty levels. The Solutions Manual gives the answer to each exercise, along with a discussion of the important points to consider and how to approach solving the problem.

ACKNOWLEDGMENTS

Many people contributed to making this book a reality, from those who spoke words of encouragement to those who read and reread the manuscript as it progressed. I thank all of you for the time and effort and support that you offered, because I know that the book would not have happened otherwise. I especially appreciate and thank my wife, Liz, for her encouragement during the years I worked on this book. Her job assignment in England during 1994 also gave me the opportunity to spend several hours every day with few distractions at "The Little House, Chiselhurst" writing several of the chapters. During that time in the U.K, Professor Robin J. H. Clark at University College London kindly allowed me access to the chemistry library at the University.

Several persons read the manuscript at various points and made valuable comments that helped focus and improve the text. For that I thank Professors Joe DeSimone, Richard Hiskey, and Gary Pielak at the University of North Carolina at Chapel Hill; Tom Bond at the University of California, San Diego; Mark Burk at Duke University; Keith Buszek at Kansas State University; Barry Carpenter at Cornell University; Sherin Halfon at the University of California, San Francisco; Bob Hanson at St. Olaf College; F. Chris Pigge, a former student who is now at the University of Missouri at St. Louis; Dagmar Ringe at Brandeis University; Charles Rose at University of Nevada, Reno; and John Swenton at the Ohio State University. Professor K. Barry Sharpless at the Scripps Institute was extremely helpful in critically reviewing the discussions about oxidation reactions and asymmetric synthesis; and Professors Bill Suggs at Brown University and Audrey Miller at the University of Connecticut each read the manuscript at two different stages. I appreciate, too, the work of Dr. Carol Dempster at the Long Island Research Institute; she not only read the manuscript but consolidated several of the other reviews to provide a coherent summary of the text's strengths and weaknesses.

Several students in my Spring semester 1998 organic chemistry class worked problems in Parts 4 and 5 of the text and gave me useful feedback about the material in those chapters. During subsequent preparation of the accompanying Solutions to Exercises, Julius Lucks, a chemistry major at University of North Carolina, worked every problem in the text and at the same time corrected many errors that had gone unnoticed through several proofreading stages. Sarah Greer, another student from that class, proofread and corrected the final draft of the solutions manual. I sincerely thank both of them for their efforts.

Finally I thank Bruce and Kathy Armbruster and Jane Ellis, of University Science Books, for their unwavering support and encouragement during the entire process. I cannot imagine working with a more interesting and fun group of people whose love of books and publishing made the whole task enjoyable. Thanks are also extended to Susanna Tadlock, the book's production manager; Robert Ishi, the designer; John and Judy Waller, the artists; and Ann McGuire, the manuscript editor.

Tom Sorrell, Chapel Hill, 1998