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Book Review Supported Reagents. Preparation Analysis and Applications. By J. H. Clark A. P. Kybett and D. J

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BOOKS
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order of time resolution (“femtochemistry”) are the subject of the ninth article
by Ahmed Zewail and Richard Bernstein.
The aim here is to observe the passage of
the system through the transition state directly as a function of time. After describing the apparatus used in their laboratory
at Caltech, the authors discuss the most
important results that femtochemistry has
yielded up to now. So far the technique
has been applied to the study of rapid decomposition reactions and oscillating intermediates (quasi-bound states). A brief
update section reporting on progress with
the method since about 1988 is also included.
The nine articles are followed by short
biographical notes on each of the authors
with photographs. The book is completed
by an index, which also lists the names of
other people mentioned in the text.
The book is equally suitable for specialists and for laypersons with an interest in
the subject. It contains a wealth of information for everyone wishing to learn
something about the current state of
knowledge in this field. Complex topics
are clearly explained without too much
glossing over of details, and mathematical
derivations are avoided completely. Thus
the book is primarily concerned with concepts and methods, and should appeal to
a wide readership.
Bernhard Dick
Institut fur Physikalische und
Theoretische Chemie
der Universitat Regensburg (FRG)
Frontier Orbitals and Properties of Organic Molecules. (Ellis Horwood Series in
Organic Chemistry. Series editor: J. Mellor.) By K E Traven. Ellis Horwood,
Chichester, 1992. XVI, 401 pp., hardcover
$11 1.OO.-ISBN 0-1 3-327 487-X
I expected to find here an up-to-date
book covering the most recent literature
in this field. Instead I found an English
translation of an obviously older Russian
work. It mainly covers work published
from the 1950s to the 1970s, with just a
few references to 1980s publications. For
the subject treated here that is quite inadequate.
The contents are arranged under two
broad areas. First is a section of about
60 pages dealing with the various methods
of describing the electronic structures of
molecules. The main part then begins with
an introduction to orbital structure and
the properties of organic molecules
(30 pp.), which is followed by a systematic
treatment of individual classes of organic
Anger.
Chem. Inl. Ed. Engl. 1994, 33, N o . 2
compounds (250 pp.). The book ends with
an appendix listing HMO data for selected molecules (10 pp.) and a bibliography
containing 471 references.
The first chapter presents in a very cursory and superficial way some basic principles of physical organic chemistry, and
is really of little value. This is followed by
an introduction to the methods of quantum chemistry, beginning with the Bohr
model of the atom and ending with some
concepts of the MO theory. The HMO
theory is then introduced, followed by a
description of the state of ab initio methods as it was twenty years ago then, as
semiempirical methods, the CNDO,
NDDO, and PPP approaches. The
MNDO, AM1, and PM3 methods appear
to be as yet unknown. Next comes a very
brief introduction to the experimental
methods for investigating the electronic
structures of organic molecules: photoelectron spectroscopy (PES), electron
transmission spectroscopy (ETS), electron spin resonance (ESR) spectroscopy,
UV spectroscopy, polarography. It becomes apparent in this chapter that
photoelectron spectroscopy is the author’s special field, and one can guess that
it is likely to figure prominently in the
later chapters. The pleasure of reading
this first part is marred by the incomplete
and superficial treatment and by the very
poor standard of English.
The second part begins with a treatment of orbital structure and reactivity,
with special emphasis on frontier orbitals.
We read that: “The rules for concerted
cycloaddition reactions proposed by
Woodward and Hoffmann were a further
development of the frontier orbitals concept.” In a similarly uncritical vein the author then goes on to consider how the orbital structure is related to biological
activity, color, and phototropic behavior.
The treatment of individual compound
classes follows the conventional structure
of a textbook of organic chemistry. Now
we come to the turn of photoelectron
spectroscopy, including calculations, some
of which are ab initio calculations of the
type used in the 1970s. There are many
tables listing ionization potentials; however, these are easily available from other
sources.
One might expect that the “properties
of organic molecules” referred to in the
book’s title would be limited to structural
features, but this turns out not to be so.
For example, in the chapter on “Alkenes”
certain aspects of the Woodward-Hoffmann rules are discussed. Under “Annulenes” one is disappointed to find that this
attractive topic is treated from a completely outdated standpoint.
0 VCH
Verlagsgese/lschafimbH, 0-69451 Weinheim, 1994
And so it goes on for one compound
class after another. The reader with a special interest in photoelectron spectroscopy
will perhaps find something of value here
and there, but the average organic chemist
will gain little from the book. To summarize, although the title sounds very
promising, it would have been better if
this book had not been translated into English. The book Frontier Orbitals and Organic Chemical Reactions by Fleming
(1976), which is not cited by Traven, is
more reliable and up-to-date than this
book published in 1992.
Reiner Sustmann
Institut fur Organische Chemie
der Universitat-Gesamthochschule
Essen (FRG)
Supported Reagents. Preparation, Analysis and Applications. By J. H. Clark, A . P.
Kybett and D.J. Macquarrie. VCH,
Weinheim, 1992. XI, 152 pp., hardcover
DM 108.00.--ISBN 3-527-28043-X
We have probably all at some time read
in a publication a sentence claiming that
by immobilizing the reagent on a support
one can improve the yield and selectivity,
facilitate the work-up procedure, etc.
These reports often leave some practical
questions unanswered: what pretreatment
and after-treatment of the support is
needed?-how does one get the reagent
on to the support? (and which support
should be chosen?)-how can the supported reagent be analyzed?-how does
one use such supported reagents to perform reactions?-and so on. This book
aims to tell the reader how to prepare and
use supported reagents, illustrating this by
practical examples.
It consists of five chapters as follows. A
general introduction to the subject is followed by separate chapters on the preparation of supported reagents and on their
analysis. The last two chapters then describe practical examples. One of these
discusses in detail, based on a few examples, the factors that need to be optimized for successful work with such
reagents. An appendix contains a table
listing various types of supported reagents
and the reactions that can be carried out
using them.
The introduction sets out to stimulate
the reader’s interest by reviewing the general field of supported reagents and the
problems. The importance of the choice of
support material is illustrated by a threepage table giving details of some reactions
chosen as examples. Unfortunately one
becomes aware here of a weakness that
OS70-0833/94/0202-0239$ 10.00f .2SiO
239
BOOKS
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persists throughout the book: the information in the table is not arranged according to reaction types, nor according
to support materials or reagents, and this
considerably reduces the usefulness of a
book which has been written for the practical user. Also it is unfortunate that the
examples in this table are not repeated in
the much more detailed table in the appendix; a combined table would have
been more useful for quick reference. In
the table in the appendix an attempt has
been made to arrange the examples according to reaction types, but this has not
turned out very successfully: for example,
the oxidation of diphenylcarbinol to benzophenone using potassium permanganate appears in three places. A commendable attempt has been made to
provide additional notes on the examples
in the table, but often these contain no
more information than is already evident
from the reaction equation. Only rarely is
one given information about yields or the
compatibility of the reagents with other
functional groups, which would have been
of interest to every user.
The initial approach to describing the
different methods of preparing supported
reagents is good. The authors’aim is to
outline general procedures for these methods and to explain them by examples. Unfortunately, however, the recipes are too
general to be used in practice for the
preparation of reagents.
The chapter on techniques for the analysis of supported reagents is well written.
The authors describe a wide variety of
methods, mainly spectroscopic, illustrated by practical examples. In addition to
the conventional spectroscopic methods
they describe some recently developed
techniques such as electron tunneling microscopy, thermogravimetry, and differential scanning calorimetry.
The “case studies” in Chapter 4 include
detailed accounts of the use of supported
fluorides, thiocyanates, and catalysts for
Friedel -Crafts alkylations and acylations. The section on thiocyanates is espe-
~~
cially interesting and comprehensive, with
detailed information on the composition
of the reagents and a table giving examples of reactions with data on reaction
times, yields, etc.
Despite all the above criticisms this is a
useful book for readers who wish to gain
a general understanding of supported
reagents. It is important to take the time
to read the whole book, but as it consists
of only 152 pages that should not be a
problem. In that way the reader will gain
a clear impression of the potential of the
reagents described and of how they might
be applied to his or her own problems.
However, as a “comprehensive reference
source” (according to the claim on the
dustjacket) the book leaves something to
be desired, both in form and arrangement
of material.
Oliver Reiser
Institut fur Organische Chemie
der Universitat Gottingen (FRG)
Just what does a referee system achieve?
Regular readers of “Angewandte” are well aware that Dr. Hans-Dieter Daniel has researched this question
using Angewandte Chemie as example. The preliminary results were presented in a communication on this
topic (Issue 2/93). Now the complete analysis by Daniel is available in book form: “The Guardians of
Science: Fairness and Reliability in Peer Review” by H.-D. Daniel, foreword by H. Noth (VCH, Weinheim,
1993, ISBN 3-527-29041-9, DM 78.-).
240
0 VCH
Verlagsgesellschajt mbH, 0-69451 Weinheim, 1994
0570-0833/94/0202-0240S 10.0O-t .25/0
Angew. Chem. Int. Ed. Engl. 1994, 33, N o . 2
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