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Book Review Analytical Electrochemistry. By J. Wang

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BOOKS
The sixteenth and final chapter is again
concerned with type I11 reactions. Here
the focus of attention is the distinction between enantiotopic and diastereotopic
atoms o r groups. In addition about 19
pages are devoted to the use of enzymes in
stereoselective synthesis.
At the end of each chapter there is a
summary of the most important points
occupying about half a page. There is an
adequate index containing about 500 entries which include all the important keywords. However, it is annoying that for
some keywords not all the relevant pagenumbers are listed; for example, the entry
for the Diels-Alder reaction fails to refer
to page 417. Altogether there are about
700 literature citations extending u p to
1992.
The author’s use of the word “echt”,
presumably borrowed from German, as in
“the design of echt type IIIr,c, reactions”
(p. 361) struck me as odd. Apart from a
few minor inconsistencies of the kind that
always slip through in the first edition of
any book, I have found only three serious
errors: on pages 21 7, 233, etc. ally1 metal
compounds are repeatedly referred to as
“alkenyl metal compounds”; in Scheme
14b on page 372 the wrong olefin is
shown; thirdly, instead of syn and anti as
introduced by Masamune, the prefixes cis
and trans are incorrectly used.
In any discussions involving stereochemistry the quality of the structural diagrams is of paramount importance. The
perspective formula diagrams used here
for the transition states are clear, but the
mushroom-like appearance of the oxygen
atoms at the ends of the backward-directed bonds (e.g. on p. 27) takes a little getting used to. The “lassos” that are occasionally shown around bonds whose
movement is indicated by arrows (e.g. on
p. 81) convey an odd sense of urgency.
The author’s decision to abandon the
usual order of presentation, based on either the stereoselective synthesis of a particular class of compounds o r the stereochemical aspects of individual reactions
(e.g. the Diels-Alder reaction), has its disadvantages. For example, it results in the
various stereochemical aspects of the
Diels-Alder reaction being treated in a
fragmented way in seven different chapters. The numerous cross-references to
other chapters are therefore really essential. On the other hand, the arrangement
of the subject matter adopted here emphasizes principles of stereoselection that are
common to different reactions, which has
the advantage of focusing the reader’s attention on an interesting new perspective
and helping him o r her to discover new
relationships. Thus, on pages 148ff the
1998
common features linking the epoxidation.
aziridination, and cyclopropanation of
alkenes are discussed, then the reactive
properties of the compounds concerned
are correlated with those of intermediates
in the halogenation of alkenes and of sulfonium and selenium ions in three-membered rings. However, as explained above
this interesting sequence of topics is not
directly derived from the proposed new
system of classification, and therefore the
usefulness of the latter is called into question.
To sum up, the above inconsistency
means that the book is not very suitable
for newcomers to the subject of stereoselective synthesis; on the other hand, for
readers who already have a basic knowledge of the subject it offers new ideas and
insights. It remains to be seen whether this
attempt at a new classification of stereoselective reactions will gain acceptance.
A . Stephen K. Hashmi
Institut fur Organkche Chemie
der Universitlt Frankfurt/Main
(Germany)
Analytical Electrochemistry. By J.
Wang. VCH Publishers, New York,
1994. 193 pp., hardcover $59.95.ISBN 1-56081-575-2
It is pleasing to note that during the last
few years the VCH group has devoted
much effort, with considerable success, to
remedying the relative neglect of electrochemistry in the available literature. Examples of successes in this field are the
new series Frontiers in Electrochemistry,
the journal Electroanalysis, and several
monographs. The latest monograph from
this publishing house is devoted to the
very interesting and highly topical area of
analytical electrochemistry, where new
methods, especially the use of electrochemical sensors, are becoming increasingly important. The choice of this currently highly interesting topic, together
with the expertise of the publishers in this
field and the high reputation of the author, hold out to users of the methods and
to students the promise of an interesting
and valuable book. Regrettably, however,
the reality does not quite come up to these
expectations.
Already in the first short chapter on the
fundamentals we find that there is no
treatment of the electrochemical potential
nor of equilibrium considerations. In the
sections on kinetics one occasionally
comes across mathematical equations
that are incomplete, derivations that are
0 VCH VL.rlugsgeselIsrhufimhH, 0-69451
Wc.inlie~m,1996
not quite correct, and statements that are
rather superficial. The poor quality of the
figures is especially noticeable. The potential is shown increasing either from right
to left or in the opposite sense depending
on the original source. Dimensions are
only partly standardized, and the symbols
used for the same quantity vary from page
to page. For example, A is first introduced
to represent the electrode surface area, but
two pages later is unashamedly used as a
probability factor. Several examples of
computations are given, which at first
seems impressive, but is less helpful than
expected: whereas the user’s difficulties
are most likely to be concerned with dimensions and orders of magnitude, the
computational problem of electroanalysis
(e.g. on p. 103) is cleverly reduced to the
dimensionless problem of the rule of
three.
Chapter 2 is mainly concerned with potential-controlled methods. Here the practitioner will find a collection of information on important instruments, relationships, and new systems. This presentation
is a considerable step forward compared
with the more conventional books by
Plambeck and others. Chapter 3 contains
much valuable practical information, including even the addresses of equipment
suppliers. The sections on modern electrodes are also very useful; aspects such as
special modifications, microelectrodes,
and methods for producing these are included. A chapter on potentiometry is followed by a discussion of biosensors and
chemical sensors; this is interesting and
up-to-date, but not very systematic. The
last 30 pages describe many new developments, in areas ranging from cyclovoltammetry to scanning tunneling microscopy.
The information on the role of electrochemistry as a modern tool of interfacial
science is useful, but is not easy to understand if one is not familiar with the principles.
Thus the book presents in an unusual
way both the successful and the less successful aspects of applied research in this
area. For the practitioner it has a certain
value as a source of information. On the
other hand, the reader who wishes to gain
an understanding of the fundamentals of
electroanalysis and modern electrochemistry will be better served by the more established works on the subject.
0570-0833~96~35/7-i9~8
3 15.00+ .25/0
Joachim Walter SchuEtze
Institut fur Physikalische Chemie
und Elektrochemie
der Universitlt Diisseldorf (Germany)
Angar. Chem. l n l . Ed. Engl.
1996, 35, N o . 17
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