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Book Review Entropy Analysis. An Introduction to Chemical Thermodynamics. By N. C. Craig

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which does not overload the reader with irrelevant details, is
one of the highlights of the two volumes, as also is the account by Barthelat and Durand of the theory of the effective
Hamiltonian operator. Such operators provide the theoretical basis for calculations on heavy atoms, and consequently
their importance can hardly be overstated. Such a readable
and full account of this topic is unlikely to be found elsewhere.
Other topics treated in these two volumes include mathematical fundamentals, atomic scattering experiments, biochemistry. quantum electrodynamics, N M R spectroscopy,
statistical mechanics, models of liquids, superconductivity,
crystal physics, and metallurgy. However, these topics are so
far removed from the title of the work that it is not possible
to review them here. Paradoxically, in contrast to this one
searches in vain for contributions on modern semiempirical
methods of calculation. It is unfortunate that readers interested in computational chemistry will have to load their
bookshelves with so much ballast in order to have access to
the few articles that are relevant.
RudoCf‘Janoschek
Institut fur Theoretische Chemie
der Universitlt Graz (Austria)
Photodissociation of Simple Molecules in the Gas Phase. By
H . Sato. Bunshin, Tokyo, 1992. V, 158pp., paperback
Yen 1100. -ISBN 4-89390-092-7-C3543-P1100E
For some years now H. Sat0 of Mi’e University has been
monitoring the literature on photodissociation processes of
small molecules in the gas phase, and at annual intervals
people interested in this field have received from him a booklet listing publications during the past year. All these references covering the years from 1970 to 1991 have now been
collected together into a book. This is the period that has
seen the laser become firmly established as a tool for photolytic studies and analysis. The book consists of two tables,
together with an associated list of over 1000 references. Altogether the compilation covers about 280 simple molecules
and more than 70 van der Waals molecules. Recently the
survey has also included organometallic compounds that are
of importance in chemical vapor deposition studies. The
structure of the tables is very simple, with entries listing the
initial molecular species, the photolyzing wavelength (or
generating source), method used to identify the breakdown
fragments, and final products, as well as the literature citation and a few brief comments. The entries are arranged
according to the initial species.
This is not a textbook, nor is it a monograph along the
lines of H. Okabe’s book Photochemistry of Small Molecules.
As Okabe notes in the foreword, it has more in common with
the much costlier spectroscopic data collection Constants of
Diatomic Molecules, by Huber and Herzberg. It is a book to
refer to when one is setting out to photolyze a new molecule
and wishes to find out what relevant work has been published recently. Thus it is intended for the active researcher,
for whom it can be thoroughly recommended. In my own
laboratory the booklets that were its forerunners have
proved invaluable when planning experiments. I would like
to have these data available on a floppy disk, which should
also make it possible to search according to reaction products.
According to the publishers, the price, including postage,
is $17.50 in the USA and $19.50 in Europe. I have just
learnt from Dr. Sat0 that Supplement VI of his collection
“Photodissociation of Simple Molecules in the Gas Phase”
Ai?,qiw. C’hem.
In[. Ed. EngI. 1993, 32. No. 4
has been published in Research Reports of the Faculty of’
Engineering, Mi’e University, Vol. 17, December 1992.
Friedrich Stuhl
Fakultat fur Chemie
der Universitat Bochum (FRG)
Entropy Analysis. An Introduction to Chemical Thermodynamics. By N . C . Craig. VCH Publishers, New York/VCH
Verlagsgesellschaft, Weinheim, 1992. XI, 208 pp.. hardcover D M 72.00.-ISBN 1-56081-539-613-527-89539-6
This book aims to provide students in their first semester
with an introduction to thermodynamics along new lines.
The author sets out to develop the fundamental laws of
thermodynamics from a global perspective instead of the
usual system-orientated viewpoint. As the title of the book
indicates, the treatment focuses on entropy as the key variable, since the first law (the conservation of energy) can be
regarded as being automatically fulfilled from the global
standpoint. The book consists of ten chapters and an appendix. After an introduction the author deals with the fundamental principles of thermodynamics (the first law, the
concept of enthalpy, the second law), then with their application to heat engines, the molecular significance of entropy,
applications to chemical reactions (the definition of the
Gibbs energy, chemical equilibria, electrochemical reactions), and the interconversion between different forms of
energy. Each chapter ends with a detailed summary of its
contents. The appendix consists of four sections. The first
short one (three pages) discusses the relationship between the
global and system-orientated approaches to thermodynamics. Two further sections contain examples to illustrate the
interpretation of the proposed concepts from the molecular
(microscopic) point of view. The last section consists of
30 pages of tables listing standard enthalpies and entropies
of formation and Gibbs energies, and specific heats of the
elements and of more than a thousand compounds, mostly
inorganic.
The global approach chosen here undoubtedly has advantages in some parts of the subject. For example, it is found
that beginners often have great difficulty with problems
where, in order to apply the second law, one has to combine
the “system” and the “surroundings” to form a new “supersystem”. The global approach avoids the complications associated with systems that are not closed. Also the description of irreversible processes is simplified. The introduction
of the molecular significance of entropy at an early stage is
a welcome feature.
However, the author incurs a penalty for his approach,
since for each process he has to consider a number of systems, each with its own internal energy. The first law takes
the form:
AU,,,,,
=
AUv
+ AU8 + AU,,+
... = 0
in which the suffix o denotes the reacting system under consideration, e denotes a heat reservoir system, and wt a
mechanical system. These systems are illustrated by diagrams. The processes that are analyzed involve an exchange
of energy between the partial systems. However, in physical
terms this compartmentalization often breaks down; to take
the simple case of an exothermic reaction in solution, the
latter is also the heat reservoir. This is an abstract idea that
the beginner will not always find easy. The fundamental
difference between the internal energy as a state function on
the one hand, and on the other hand the concepts of work
VCH Verlagsfiesellschufi mhH. W-6940 Weinheim, 1993
0570-0833/93/0404-062f$ 10.00i ,2510
621
input and heat introduced o r removed, which are not state
functions, does not clearly emerge. The concepts of work
and heat are replaced by the energies of the mechanical system and of the heat reservoir system, respectively. For the
relationship between the two approaches one has to go to the
appendix. It seems very doubtful whether the approach
adopted here will really help the student to gain a deeper
understanding of thermodynamics and apply it to practical
situations later on.
The avoidance of using the methods of differential and
integral calculus will certainly be helpful to first-semester
students, who d o not usually have a sufficient mathematical
background at this stage. However, by the second semester
at the latest, a more exact mathematical formulation becomes essential; the usual level of thermodynamics lecture
courses in Germany at this stage goes beyond that of the
book. In many cases, therefore, the student will then need to
switch to a different approach, and there is a risk that the
earlier simplifications will become a hindrance to a deeper
understanding.
Within the intended scope of the book, the treatment is, on
the whole, rigorous. Nevertheless, it seemed to this reviewer
that in some places the author makes statements, in anticipation of later discussions, that could be misunderstood. Although these are later corrected when the topics are treated
in detail, there is a risk that by then the reader has the
misconceptions so firmly in his or her head that it is difficult
to correct them. For example, the statement in Chapter 4
(p. 42) that entropy is a measure of disorder is inappropriate
in relation to the subsequent more detailed treatment in
Chapter 6. In Chapter 3 reference is made to the heat capacity of the thermal reservoir before the specific heat cp has
been defined. Also the short section on “the molecular basis
of the reaction enthalpy” is not very helpful.
There are many exercise problems at the end of each chapter, sometimes with hints on the method of solution. The
consistent use of SI units throughout is a good feature. The
high price of the book will deter students from buying it,
especially since it scarcely goes far enough to cover the first
semester of study.
Friedrich Temps
Institut fur Physikalische Chemie
der Universitat Gottingen (FRG)
Organic Synthesis with Oxidative Enzymes. By H . L. Holland. VCH Verlagsgesellschaft, Weinheim, 1992. XI,
463 pp., hardcover DM 168.00.--ISBN 3-527-27956-3
Biocatalysis techniques are increasingly developing as attractive alternatives to well established conventional chemical methods for many chemical transformations. This applies also to oxidations, as is impressively shown by H. L.
Holland in this book. The applications of oxidoreductases in
organic synthesis are summarized here in ten chapters, each
plentifully illustrated with formula schemes and supported
by a comprehensive and up-to-date bibliography (up to May
1990). Although alcohol dehydrogenases can also be used
oxidatively, these are not covered. The book is intended for
organic chemists who wish to learn about the capabilities of
oxidative biotransformations and their use on a preparative
scale. Some of these can be performed using isolated enzymes, which are even commercially available in a few cases,
but the majority of the transformations described are only
possible by using whole cells, i.e. living microorganisms. Although this whole cell technology has already been estab622
0 VCH
VFrlRgSgFSe//SChRfi
mhH. W-6940 Weinheim. 1993
lished in industry for several decades, e.g. for the hydroxylation of steroids, its applications to organic syntheses in other
fields has so far been minimal compared with the use of
isolated biocatalysts. One reason for this is that up to now
the majority of oxidases have been difficult or impossible to
obtain in active form together with the necessary cofactors
and activators. A second reason is that many organic
chemists still feel a great aversion and reluctance to use
methods that are “too biological”, and are therefore not very
amenable to being controlled a n d - e v e n more importantly-rationalized. Mindful of this obstacle to getting started,
Holland has followed his introductory chapter, in which he
describes the basic mechanisms of enzymic catalysis by
mono- and dioxygenases, peroxidases, and also reductases,
with a chapter on general laboratory techniques for performing biotransformations. In this he describes briefly how one
goes about obtaining the microorganism needed for the purpose, and then how the actual transformation is carried out.
The following seven chapters present the current state of
the art regarding the most important organic biotransformations. Chapter 3 describes hydroxylations at saturated carbon atoms; the main emphasis is on steroids and terpenes,
but also included are hydroxylations at the benzylic position
in a wide variety of arenes, and applications to N-dealkylations. Chapter 4 deals with oxidations of unsaturated CC
bonds, describing biocatalytic epoxidations of olefins and
arenes, and the currently very interesting conversion of aromatic hydrocarbons to enantiomerically pure cis-dihydrodiols as useful synthetic building blocks. Chapter 5 is concerned with biocatalytic Baeyer-Villiger oxidations, and
Chapter 6 with oxidations at heteroatoms such as nitrogen
and sulfur to give N-oxides, sulfoxides, sulfones, etc. Chapter 7 describes the conversion of CC single bonds to double
bonds, with special reference to steroids and fatty acids, then
in the following chapter the author collects together all the
reactions that cannot be categorized under the previous
headings. These include, for example, the oxidative coupling
of phenols and their oxidation to quinones, and the biocatalytic breakdown of alkyl chains. In the penultimate chapter,
which is very long in keeping with its importance, Holland
describes reductive biotransformations, including the enzymic removal of hydroxy groups and halogens, the reduction of sulfoxides to sulfides and of N-oxides to amines, and
especially the conversion of isolated double bonds and x$unsaturated carbonyl compounds to the corresponding saturated hydrocarbons. Lastly, Chapter 10 contains a survey of
the many different types of enzyme-catalyzed syntheses described in the foregoing chapters, and with this as the theme
the author gives advice, especially for the non-specialist, regarding criteria for identifying a suitable microorganism to
perform a particular conversion. After also discussing the
possibility of applying genetic engineering methods, the
book ends with a brief, but optimistic, review of future
prospects.
H. L. Holland has produced here a book that sets new
standards. He informs the reader expertly, comprehensively,
and without unnecessarily lengthy detail, about the capabilities and range of applications of the various biocatalysts
described. He has wisely resisted the temptation to view his
special subject through rose-colored spectacles and praise it
to the skies. In every case he presents a critical evaluation,
indicates perspectives, and points out examples where biocatalysis offers no advantages compared with conventional
methods. In accordance with his self-imposed task of addressing organic chemists and helping them to make decisions and overcome fears, whenever possible Holland gives
topical examples illustrating how the products from biosyn-
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0570-0833/93j0404-0622B 10.00 ,2510
Angew. Chewt. hi.Ed. Engl. 1993, 32. N o . 4
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