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Book Review Metals and Ligand Reactivity. By E. C. Constable

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nuclei. It is never completely clear, especially to a novice
audience, that methods such as inversion-recovery and CarrPurcell-Meiboom-Gill experiments are general methods for
observing general phenomena. One-dimensional experiments using pulse sequences are covered in Chapter 8. Spinechoes are covered well, and the treatment of the INEPT and
refocussed INEPT experiments is particularly good. Unfortunately, several vector pictures in this chapter are extremely
confusing and detract from the lucid description in the text.
It is important to remember that trying to oversimplify problems often results in overloading the reader with too much
information at one time. Two-dimensional NMR experiments are covered in Chapter 9. Particularly good here is the
slow development of the heteronuclear correlation experiment, taking the method from its intuitive beginnings
through to a usable pulse sequence. Descriptions of spectral
widths as related to the incrementable delay period and
phase sensitive spectra would make a useful addition here.
Only basic two-dimensional experiments are covered, and
many of the recent and powerful two-dimensional methods
are not presented.
Chapter 10, developing the idea of the NOE, is well explained and very understandable and leads nicely into Chapter 11 on dynamic NMR. This section, including lineshape
analysis and coalescence, is packed with informative examples. Rotations about bonds, ring inversion, tautomerism,
and exchange effects are all described with clarity. Bringing
the book to a close are chapters on shift reagents, macromolecular applications (synthetic polymers) and, surprisingly, medical applications including in vivo studies and magnetic resonance tomography.
In summary, this text provides a reasonably successful
introduction to basic NMR ideas. Its greatest asset is that it
is written at a level that is accessible to students across a wide
range of disciplines and consequently would make a useful
basis for an introductory teaching course. The reservations
that exist include the lack of clarity and accuracy in some of
the figures and the fact that the enormous power of two-dimensional NMR is not conveyed to an appropriate extent.
John Cuvanugh [NB 1175 IE]
Department of Chemistry
University of Cambridge
Cambridge (United Kingdom)
computational Chemistry Using the PC. By D. U.: Rogers.
VCH Verlagsgesellschaft, Weinheim 1990. viii, 224 pp.,
hardcover DM 98.00. - ISBN 3-527-27937-7
The term “computational chemistry” does not have a very
precise definition. In the title of this book it essentially means
molecular mechanics and molecular orbital calculations and
the numerical methods on which these are based. In contrast
to the numerous monographs dealing with the theory of
molecular and quantum mechanics, this book aims to give
an introduction to programming such methods and applying
them. This seems a very sensible approach, and the book
succeeds in its aims. Most “computer chemists” have become involved in this field in an unplanned way through
modifying already existing programs to perform new tasks,
and have had to acquire the necessary expertise in numerical
mathematics from a variety of sources. This book now offers
a systematic introduction, ranging from the basic numerical
methods to working with ready-made HMO and SCF programs. Each chapter includes many exercise problems, for
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which solutions are provided in most cases. The book also
includes “computer projects”, a form of learning aid which
is an innovation, at least in the context of a textbook. Each
one consists of a set of guidelines for solving a physical
chemical problem using a computer program. The programs, most of which are written in BASIC, are supplied
with the book on a S1/4-inch diskette suitable for running on
any IBM-compatible PC operating under DOS.
The book is divided into two parts. The first six chapters
present the basic principles of programming numerical methods. Iterative methods and numerical integration methods
are explained with the help of examples from physical chemistry (e.g. the van der Waals equation, Wien’s law, and the
Maxwell -Boltzmann distribution). These are followed by
matrix operations and curve-fitting. The last seven chapters
of the book are concerned with molecular orbital calculations, molecular mechanics, and molecular graphics. In the
treatment of MO theory, if not even earlier, the author encounters a basic difficulty that is inherent in the task he has
undertaken, namely whether to introduce the reader to
quantum theory (and thereby make the book considerably
more bulky), or to assume this knowledge. He decides in
favor of a middle road. The theoretical introductions are
short and very condensed. Consequently, if the book is to be
used as a self-study text one must already be familiar with the
main fundamentals, or must use it in conjunction with a
textbook of theoretical or physical chemistry. Subject to
these preconditions, the chapters on molecular mechanics
and MO methods (Huckel, EHT, PPP, MNDO, ab initio,
etc.) provide a deeper insight into how these programs function.
The book fills an important gap that has existed between
those (very few) books dealing with the application of the
most popular molecular mechanics and MO programs to
chemical problems (e.g. T. Clark’s “Handbook of Computational Chemistry”) and the actual textbooks of theoretical
chemistry. It is shown here that as a result of the present state
of development of PCs, the excellent programs already available can now be usefully run on cheap hardware that nearly
all students can afford. The high price of the book is in
marked contrast to this, but on the other hand the perfect
typography that is typical of the publishers, VCH, is a delight to the eye. The book is outstandingly suitable as a
self-study text for lecturers and students of graduate level
and beyond. It is especially recommended for users of black
box program systems such as GAUSS or MOPAC who
would like (and indeed ought) to gain a somewhat better
understanding of what they are calculating.
Ruiner Herges [NB 1 1 32 IE]
Institut fur Organische Chemie
der Universitat Erlangen-Nurnberg (FRG)
Metals and Ligand Reactivity. By E. C. Constable. Ellis Horwood, New York 1990. xii, 246pp., hardcover $54.50. ISBN 0-13-577222-2
The rapid development from about 1960 onwards of the
new organometallic chemistry with its sometimes exotic
structures and bonding situations, temporarily pushed the
study of classical coordination compounds into the background. During the 1950s the latter were at the center of
attention in molecular inorganic chemistry as a result of the
successful combination of spectroscopy, reactivity studies,
and ligand field theory. Now their importance is gradually
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Angew. Chem. hi.Ed. Engi. 30 (199i) No. 10
becoming generally appreciated once again, especially
through the rise of bioinorganic chemistry as a new field of
research. However, even leaving aside the remarkable catalytic capabilities of the metal centers in enzymes, many organic chemical transformations that are made possible or are
catalyzed by non-organometallic coordination compounds
are indispensable in laboratory synthesis and technological
processes. Whether one already has an interest in the subject
or has previously regarded classical coordination chemistry
as boring, weighed down with theory, and irrelevant, it will
be found that Constable’s account is a thoroughly readable
one that offers an agreeable way of catching up on developments. The main emphasis in this monograph is on using
(transition) metal centers to influence the reactivities of
organic compounds that have coordination sites formed by
heteroatom donors.
The particular features that make this an easy book to
read are its emphasis on synthetically useful reactions and
the absence of lists of physico-chemical data and literature
citations in the main text. References for further reading are
collected at the end of the book under topic headingswhere the author gives more detailed information.
Constable begins with a very brief introduction to the orbital models needed. Regrettably, however, the qualitative
description of chemical reactivity does not include catalytic
aspects. Coordinative bonding, both with and without x
interaction, is described from the standpoint of electrostatic
interactions and geometry in a clearly understandable way.
The descriptions of examples begin with the chapters on
attack by nucleophiles, including H,O and OHe, on metalcoordinated carbonyl compounds and their derivatives (nitriles, imines), on sulfur compounds, and on phosphoric acid
esters. These are followed by a chapter discussing electrophilic attack on metal-stabilized anions such as enolates
or thiolates and on neutral bases (e.g. metal-induced amineimine transformations).
Another chapter describes template reactions that lead to
ring closure, with a general discussion of the special characteristics of macrocyclic systems with regard to stability, resistance to attack, metal selectivity, and geometric strains
caused by imperfectly matching metal ions. Supramolecular
structures, including knotted molecules, continue to be a
source of fascination. The special characteristics of aromatic
substrates are discussed, with particular emphasis on the
substitution reactions of metal-coordinated N-heterocycles
of the pyridine type. The description of redox processes is
limited to transition metal catalyzed reactions with 0, ,
which are of practical importance, but whose mechanisms
are not always as they seem at first sight. It is pleasing to note
that here, at last, a clear distinction has been made between
the processes of electron transfer, dehydrogenation, and
oxygen transfer. The final chapter, entitled “Envoi”, contains a very brief, and consequently rather simplified
account of the search for an overall rationalization of
the catalytic capabilities of coordinated metal ions in enzymes.
The contents of the book are clearly arranged and well
presented, matching the author’s excellent lecturing style.
The many formulas are well prepared, except for a few ring
systems and the inconsistent use of arrows for coordinative
bonds. The popular structure diagrams as reproduced from
X-ray diffraction studies are few in number so that the reader
obtains a rather limited appreciation of the complex geometries. On the other hand, the summaries given at the end of
each chapter and the pithy critical evaluations scattered
throughout the text are especially useful. Thus, for the reader
who, for a relatively small cost in time and money, wishes to
Angew. Chem. Int. Ed. Engl. 30 (1991) No. 10
acquire as much practical, useful knowledge of coordination
chemistry as possible, this book is recommended unreservedly.
Wo[fgang Kaim [NB 1131 IE]
Institut fur Anorganische Chemie
der Universitat Stuttgart (FRG)
Sonochemistry: The Uses of Ultrasound in Chemistry. Edited
by I: J. Mason. The Royal Society of Chemistry, London
1990. 151 pp., paperback $89.25.-ISBN 0-85186-293-4
Chemical applications of ultrasonic waves, often referred
to as sonochemistry, enjoyed a renaissance in the eighties.
These books are introductory in nature, intended for the
chemist with a potential interest in the field. The first is more
general, while the second will be of more interest to synthetic
chemists.
There are nine contributors covering an important range
of topics in eleven chapters: I:J. Mason provides an
overview of the field in the first chapter (8 pages, 10 references) dealing with historical aspects, non-chemical uses of
ultrasound (diagnostics), power ultrasound, and specific examples of ultrasound enhanced chemical reactions. The incorrect attribution of Regen’s work on dichlorocarbene to
Repic is unfortunate. Chapter 2 (“Sonochemistry, the General Principles”, .L P . Lorimer, 18 pages, 5 references) offers
a lucid discussion of wave propagation, particle displacement due to a longitudinal wave, factors affecting cavitation,
and the fate of a bubble in a sound field. It is one of the best
chapters in the book, marred only by the conspicuous absence of a discussion of the “hot spot” theory and Suslick’s
vapor shell.
The third chapter (“Ultrasound in Diagnosis, Inspection,
and Monitoring”, C . S. Gartside and M . M . Robins,
20 pages, 6 references) is simply out of place and dilutes the
effort of such a small book. Chapter4, (“Power Ultrasound”, J. P . Perkins, 13 pages, 5 references) deals with
some important fundamental concepts such as monitoring
acoustic input and output, construction of the transducer,
cavitation phenomena, health and safety aspects, and large
scale applications, but would be more effective if blended
efficiently with topics in Chapters 2 (see above), 5 (“A Survey of Commercially Available Sources of Ultrasound Suitable for Sonochemistry”, I:.L Mason, 9pages, no references), 10 (“The Uses of Ultrasound in Chemical
Technology”, I: J. Mason, 6 pages, 13 references), and 11
(“Scale-up Considerations”, I: J. Goodwin, 14 pages,
4 references). There is a good deal that is useful in these
chapters but the fragmentation of information and unnecessary repetition detract from them.
Chapters 6 (“Ultrasound in Organic Synthesis”, R. S.
Davidson, 17 pages, 38 references), 7 (“Free Radical Reactions under Sonochemical Conditions”, J.-L. Luche,
15 pages, no references) and 8 (“Ultrasound in Heterogeneous Catalysis”, J. Lindley, 8 pages, 89 references) discuss
much of the important literature of interest to synthetic
chemists. It is distracting that a number of the references in
Chapters 6 and 8 are simply incorrect and others have an
author’s name misspelled.
There is overlap among the chapters that a small book can
ill afford. As examples, precious space is wasted on two
discussions with schemes by Davidson and Luche, of Luche’s
free radical ring closure of benzamide and of his elegant
preparation of dialkylzinc compounds. Likewise, Davidson’s
treatment of continuous ultrasonic hydrogenation of soy-
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