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Book Review Fundamentals of Nuclear Magnetic Resonance. By J. W. Hennel and J. Kilnowski

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The literature coverage now extends to
mid-1990, while at the same time some
outdated references have been dropped.
There are 1700 new literature citations,
bringing the total to over 3600. now listed
(unlike the earlier editions) in alphabetical
order. The subject index too is a valuable
aid when working with this book.
Goldberg‘s book on the same subject is
based on one originally published in Russian in 1989. which has been revised and
updated for this English version. It contains about 1300 literature references extending up to 1991. The subject index.
which is mainly substance-orientated, is a
useful working aid.
The book by Dehmlow and Dehmlow
begins with two chapters of more than
60 pages altogether on the theoretical
basis of PTC. The first chapter is mainly
concerned with the principles underlying
the effectiveness of the most important
types of catalysts, while the second deals
with the mechanistic aspects of the different variants of the PTC method. Chapter 3 (over 300 pages long) is concerned
with synthetic applications of PTC. It begins with a section on the choice of reaction conditions, such as the type and
quantity of catalyst, the solvent, and the
stirring rate. Particular attention is given
to enantioselective PTC, describing its applications, problems. and the many potential sources of error. Next the authors describe various practical applications of
PTC, arranged so far as possible according to reaction types. These include substitutions leading to alkyl halides, nitriles,
esters, thiols. sulfides. and ethers. N - and
C-alkylations, alkylations and acylations
of ambidentate anions, isomerizations,
H / D exchange reactions. and additions at
C = O and C = N bonds. Also treated in
detail are r-, p-, and y-elimination reactions, the preparation of phosphonium
and sulfonium ylides. nucleophilic aromatic substitutions, applications of PTC
to organometallic compounds. and reducrims and oxidations. I t is pleasing to find
that as well as giving well-proven synthetic recipes the authors include general principles that have been derived for carrying
out various types of transformations under phase transfer conditions. The large
amount of factual information is very
clearly presented. often in the form of
tables. enabling the reader not only to
quickly find specific details but also to get
an overview of a chosen area.
Goldberg’s book differs considerably
from that of Dehmlow and Dehmlow.
both in emphasis and in structure. A first
chapter (24 pp.) dealing with the theoretical fundamentals is followed by several
chapters describing some selected areas of
application of PTC. Chapter 2. the
longest in the book with about 100 pages.
is concerned with PTC in the chemistry of
N-heterocycles. Alkylations and acylations of compounds of this class are described, as also arc reactions of halogenated N-heterocycles with nucleophiles.
Reactions of N-heterocycles with carbenes are treated next, followed by oxidations and reductions, as well as the use of
PTC in the preparation of such compounds. In Chapter 3 (about 50 pp.). on
PTC in organometallic chemistry, much
attention is devoted to reactions iiivolving
organosjlicon compounds; other reactions discussed include those of mercury.
molybdenum, tungsten, iron, cobalt, and
platinum compounds. Chapter 4 (about
70 pp.) is devoted to catalysis by metal
complexes under phase transfer conditions, including reductions, oxidations.
dehydrogenations, and carbonylations.
Chapter 5. on three-phase catalytic reactions (about 30 pp.), discusses the advantages and disadvantages of using quaternary onium salts. crown ethers. or
open-chain polyethers immobilized on
polymers or other substrates for a variety
of reactions. In Chapter 6. on asyminetric
phase transfer catalysis (about 50 pp.),
Goldberg discusses in great detail a number of types of reactions for which PTC
has proved more or less successful. He also analyzes a number of experiments that
failed completely and were thus of no interest for synthetic purposes, and identifies the factors that previously led to
wrong interpretations. These latter discussions are extremely valuable for any
chemist intending to apply PTC to asymmetric syntheses for the first time. However. reactions giving optical purities of
15-19% should not be regarded as satisfactory, as is implied on page 299. Chapter 7 (about 40 pp.) is concerned with less
common variants of PTC; here the author
discusses cationic reactions, reactions at
phase boundaries between neutral species.
inverse PTC, electron phase transfer, and
reactions under the influence of ultrasonic
excitation at phase boundaries.
The book by Dehmlow and Dehmlow
is a standard work on PTC. affording the
reader a comprehensive overview ranging
from the theoretical fundamentals to the
diverse wealth of practical applications of
this useful method in synthetic chemistry.
It is an indispensable monograph for every chemist. being suitable not only for
organic chemists with experience of PTC
but also for those about to use this
method of synthesis for the first time.
Goldberg’s book does not give such a
comprehensive picture. nor was that the
author’s aim. Instead it is intended for
specialists. Because of this quite different
approach it may be regarded as complementary to the Dehmlow and Dehmlow
monograph. extending the subject and
treating it in greater depth, with detailed
discussions of many applications of PTC.
At some points one might say that it gives
too much information-for example, the
details given beside the reaction arrows of
the synthesis schemes. In both books the
subject matter is clearly arranged, in a
readable style, and in a sturdy binding.
No library should be without them.
Fritz Theil
Institut fur Angewandte Chemie
Berlin-Adlershof (FRG)
Fundamentals of Nuclear Magnetic
Resonance. By J. W Hennel and J.
Klinowski. Longman, Harlow (UK),
1993. 288 pp., paperback f 22.50.ISBN 0-582-06703-0
In their preface the authors formulate
their aim: it is to explain the physical and
mathematical basis of NMR sinTp/y but
exactly. In a certain sense they succeed.
However, the question is: what m e the
fundamentals of nuclear magnetic resonance? In the opinion of the authors they
are the magnetic dipole moment (of a
compass needle, a current loop. an orbiting electron, or a nucleus with a spin), the
magnetization of a macroscopic sample in
thermodynamic equilibrium. the Larmor
precession of an isolated spin, Bloch’s
equations, the Fourier transformation,
the Zeeman and dipolar parts of the
Hamiltonian. the method of (second)
moments, and the spin-echo and COSY
experiments.
Sure, all these topics are fundamentals
of NMR. and I would regard it as almost
a moral obligation of all those who practise N M R to be thoroughly familiar with
fundamentals of this kind. It may well be
the experience of Jacek Hennel and Jacek
Klinowski that only too many are not.
And I must admit that the authors’
overview and judgement are very likely
quite correct. Therefore, let us admit that
there is a need to explain such fundamentals simply and exactly. Does the book
fulfill the promise?
It starts with a chapter of 42 pages on
the “Elements of Quantum Mechanics”.
It is supplemented by five appendices explaining topics from “Complex Numbers” to “Sinusoidal Operators.” This is
now the third recent book on N M R which
I have read in which the authors assume,
on the one hand, that they must provide
an introduction to complex numbers and.
BOOKS
on the other. that their readers should
master quantum mechanics up to the
(spin) density matrix, the Hilbert space
and the like. In my opinion it is a complete
illusion to hope that someone who needs
an introduction to complex numbers is
able to appreciate any exposition of quantum mechanics. I am afraid, therefore,
that Hennel’s and Klinowski’s book is of
little help to those who have not previously followed a course in quantum mechanics. For those who have done so (and have
worked through their homework problems) the book may be a useful revision.
and they may like to see how quantum
mechanics is applied cwx-tly and simply
and at great length to practical cases.
However, a major problem is that the
book does not lead the reader far enough.
Almost all the fundamentals remain on an
educational, a cultural level. They d o not
open the door to practical modern N M R .
On the whole the book breathes the air of
the fifties. maybe sixties. Pake’s ingenious
but hopelessly obsolete “high frequency
bridge“ is described to illustrate how
N M R is detected. Pulse and F T N M R are
discussed but no modern probehead or related instrumentation is shown. Of the total of 54 references no less than 37 appeared in o r before 1967. and 19 of these
are from the fifties. All those from after
1980 are monographs and textbooks.
Abragani appears under 1983, whereas I
bought my copy of his book in 1961.
The final chapter is on “Nuclear Magnetic Relaxation”. It brought me an almost nostalgic re-encounter with Gierer
and Wirtz (1953) and their microviscosity
coefficients. I had hoped for a more up-todate climax. I recommend the book for
introductory N M R teaching. either in a
class or in a laboratory course, and to all
those who d o practical N M R work and
desperately feel that they d o not really understand the fundamentals of their experimental tool. But they should not expect a
link between these fundamentals and their
own work.
U. Hueherlen
Max-Planck-Institut
fur medizinische Forschung
Heidelberg (FRG)
Neural Networks for Chemists. An
Introduction. By J. Zupan and J.
Gasteiger. VCH Verlagsgesellschaft, Weinheim/VCH Publishers,
New York, 1993. 305 pp., hardcover
DM 138.00, paperback DM 68.00.
-ISBN
3-527-28592-X/1-56081791-7 (hardcover), 3-527-28603-91
1-56081-793-3 (paperback)
To explain precisely the basic concepts
of a new interdisciplinary area of research
and communicate them to a wide readership is a difficult task. Jure Zapan and
Johann Gasteiger have managed to d o
this very successfully. This book offers a
sound introduction to artificial neural
networks, with insights into their architecture, functioning, and applications, which
is intended not only for chemists but also
for scientists from other disciplines. The
capabilities and limitations of different
systems are compared and evaluated. The
authors have sensibly limited their treatment to a few carefully chosen and clearly
distinguished types of networks, explaining
how they are used for classifying, modeling, and analyzing molecules and their
properties, for evaluating visual images
(e.g.. to interpret spectra o r to analyze
structure-activity relationships), and for
controlling chemical reactions. The book
is written in a readable style and is well
structured. The reader’s task is made easier by providing a short summary of the
main learning objectives at the start of
each chapter, and by the use of easily remembered mnemonics. The treatment is
divided into two parts, one concerned
with theory and the other with describing
different types of applications. This arrangement means that, after studying the
clear and very informative introduction to
the topic, the reader can look at the examples of applications and assess the suitability of the chosen method in each case,
possibly even suggesting an alternative solution. The chapters on Kohonen networks and counterpropagation systems
are especially good. The examples of applications, such as the representation of
the three-dimensional electrostatic potential of a molecule in the form of a two-dimensional map using the Kohonen approach, surprise one at first by the
simplicity of the concepts, but this is in
itself an illustration of one of the strengths
of artificial neural networks. The authors
explain clearly and concisely how these
principles can be applied in order to make
an appropriate selection of representative
data for an analysis using neural networks. The reader is not distracted from
the core issues by too many literature references in the text; instead the authors
give a useful selection at the end of each
chapter.
In OUJ view there are only a few aspects
of neural networks that have not been fully covered in the book. The authors have
not discussed effective algorithms for the
systematic optimization of network architectures --for example, genetic algorithms.
Also, in restricting the discussion to the
back-propagation algorithm for multipositional networks the authors have covered only a part (admittedly by far the
largest) of the range of reliable strategies
for supervised learning. A similar criticism
applies to the choice of applications. In
particular. the analysis of biological
macromolecules receives only marginal
treatment, being limited to predicting the
three-dimensional structures of proteins
from their amino acid sequences. Here it
would have been desirable to include
some more examples -e.g., the use ofneural networks to analyze data banks- -as
these methods have already advanced
considerably and much effort is being put
into further developments. However. additional topics such as these can no doubt be
included in a second edition. This is a very
well-written guide for anyone who wants
to make greater use of information theories in chemistry. The excellent quality of
the contents and the presentation should
ensure that it reaches a wide international
readership.
Gisbert Schneidu. Paul Wrerle
Institut fur Medizinischel
Technische Physik und Lasermedizin
der Freien Universitiit Berlin (FRG)
Homogeneous Transition Metal Catalyzed Reactions. Edited by W R.
Moser and D.W Slocum. (Series:
Advances in Chemistry, Vol. 230.)
American Chemical Society, Washington, DC, 1992. 625 pp., hardcover $! 139.95.-ISBN 0-8412-2007-7
This book contains a substantial number of the presentations from the symposium on “New Science in Homogeneous
Transition Metal Catalyzed Reactions”,
held during the 199th National Meeting of
the American Chemical Society, in Boston,
Massachusetts, April 22-27, 1990.
About one third of the chapters have
been written by chemists working in industrial laboratories. The authors are in
general very well known for their contributions to the field. The fact that the papers are subjected to the editorial standards of the ACS is a further warranty for
the high quality of the book.
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