The
twentieth century saw the birth of physical organic chemistry—the study of the
interrelationships between structure and reactivity in organic molecules—and
the discipline matured to a brilliant and vibrant field. Some would argue that
the last century also saw the near death of the field. Undeniably, physical
organic chemistry has had some difficult times. There is a perception by some
that chemists thoroughly understand organic reactivity and that there are no important
problems left. This view ignores the fact that while the rigorous treatment of
structure and reactivity in organic structures that is the field’s hallmark
continues, physical organic chemistry has expanded to encompass other
disciplines.
In
our opinion, physical organic chemistry is alive and well in the early
twenty-first century. New life has been breathed into the field because it has
embraced newer chemical disciplines, such as bioorganic, organometallic,
materials, and supramolecular chemistries. Bioorganic chemistry is, to a
considerable extent, physical organic chemistry on proteins, nucleic acids,
oligosaccharides, and other biomolecules. Organometallic chemistry traces its
intellectual roots directly to physical organic chemistry, and the tools and
conceptual framework of physical organic chemistry continue to permeate the
field. Similarly, studies of polymers and other materials challenge chemists
with problems that benefit directly from the techniques of physical organic
chemistry. Finally, advances in supramolecular chemistry result from a deeper
understanding of the physical organic chemistry of intermolecular interactions.
These newer disciplines have given physical organic chemists fertile ground in
which to study the interrelationships of structure and reactivity. Yet, even
while these new fields have been developing, remarkable advances in our
understanding of basic organic chemical reactivity have continued to appear,
exploiting classical physical organic tools and developing newer experimental
and computational techniques. These new techniques have allowed the
investigation of reaction mechanisms with amazing time resolution, the direct
characterization of classically elusive molecules such as cyclobutadiene, and
highly detailed and accurate computational evaluation of problems in reactivity.
Importantly, the techniques of physical organic chemistry and the intellectual
approach to problems embodied by the discipline remain as relevant as ever to
organic chemistry. Therefore, a course in physical organic chemistry will be
essential for students for the foreseeable future.
This
book is meant to capture the state of the art of physical organic chemistry in
the early twenty-first century, and, within the best of our ability, to present
material that will remain relevant as the field evolves in the future. For some
time it has been true that if a student opens a physical organic chemistry
textbook to a random page, the odds are good that he or she will see very
interesting chemistry, but chemistry that does not represent an area of
significant current research activity. We seek to rectify that situation with
this text. A student must know the fundamentals, such as the essence of
structure and bonding in organic molecules, the nature of the basic reactive
intermediates, and organic reaction mechanisms. However, students should also
have an appreciation of the current issues and challenges in the field, so that
when they inspect the modern literature they will have the necessary background
to read and understand current research efforts. Therefore, while treating the
fundamentals, we have wherever possible chosen examples and highlights from
modern research areas. Further, we have incorporated chapters focused upon
several of the modern disciplines that benefit from a physical organic approach.
From our perspective, a protein, electrically conductive polymer, or
organometallic complex should be as relevant to a course in physical organic
chemistry as are small rings, annulenes, or nonclassical ions.
We
recognize that this is a delicate balancing act. A course in physical organic
chemistry cannot also be a course in bioorganic or materials chemistry. However,
a physical organic chemistry class should not be a history course, either. We
envision this text as appropriate for many different kinds of courses, depending
on which topics the instructor chooses to emphasize. In addition, we hope the
book will be the first source a researcher approaches when confronted with a new
term or concept in the primary literature, and that the text will provide a
valuable introduction to the topic. Ultimately, we hope to have produced a text
that will provide the fundamental principles and techniques of physical organic
chemistry, while also instilling a sense of excitement about the varied research
areas impacted by this brilliant and vibrant field.
Eric
V. Anslyn
Norman Hackerman Professor
University Distinguished Teaching Professor
University of Texas, Austin
Dennis
A. Dougherty
George Grant Hoag Professor of Chemistry
California Institute of Technology