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Book Review Transient Techniques in Electrochemistry. By D. D. MacDonald

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Experimental
(2a) from (3): Dry HCI is slowly introduced into a refluxed
suspension of 0.01 2 mol PI (R = Me) and 0.01 mol(3) in 60 ml
dry CHCI3 until all the PI has dissolved. The residue obtained
after evaporation of the solvent is distilled in a Kugelrohr
at 85-9ODC/O.0l torr; 2.03g (86%) of ( 2 a ) is obtained as
a colorless oil.-Similarly, with PI, R = C2H5and NR2 = pyrrolidino, 93 % of (2b) and 90 % of (2c), respectively, were
obtained.--(2u) from 1.5): A suspension of 0.045mol PI
(R=CH3) and 0.04mol dichloroacetonitrile in 100ml anhydrous CHC13 is refluxed in the presence of gaseous HC1 until
all the PI has dissolved. Yield after workup (see above): 88 %.
( 4 ) from (3): A solution of 0.01 mol of (3) in 20ml
anhydrous CH2C12 is added to a stirred solution of 0.01 mol
VHA in 40ml of the same solvent at O T , while anhydrous
HC1 is introduced slowly into the reaction mixture (about
one hour at 0°C). The solution is then refluxed for 30min,
the solvent is removed and the residue washed twice with
ether. The yellow powder so obtained is treated with a concentrated solution of K 2 C 0 3 and extracted with CH2CI2.After
drying and removal of the solvent, ( 4 ) is obtained as a white
powder. Yield: 65-75 %.-Hydrochloride of ( 4 ) from (5):
A solution of 0.03mol (5) in 50ml anhydrous CH2C12 is
added dropwise to a solution of 0.03 mol VHA in 80ml anhydrous CH2CI2saturated with dry HC1 and cooled to - 20°C.
After about two hours the mixture is allowed to slowly warm
to room temperature. The solvent is partially removed in
a rotary evaporator, whereupon yellowish needles crystallize
out; yield 60-65 %.
Received: January 30, 1979 [Z 181 lE]
German version: Angew. Chem. 91. 355 (1979)
CAS Registry numbers:
( 2 0 ) . 69668-53-7; ( Z b ) , 69687-68-9; (2c), 69668-54-8; (31, 53472-29-0; ( 4 ) .
69668-55-9; (4/-HCI, 69668-56-0; (S), 3018-12-0; ( 6 ) . HCI, 69668-57-1; (71,
69668-58-2; (X), 69668-59-3; P1.HCI (R=CH3), 69668-60-6; PI.HCI
lR=CzHs), 69668-61-7; PI’HCl (NR,=pyrrolidine), 69668-62-8; VHA’HCI,
3724-43-4; benzamidine, 618-39-3; hydrazine hydrate, 7803-57-8; m-methoxyaniline, 536-90-3
~
~~
~
[l] For a review see Z . Junousek, H . G . Viehe in H . BBhme, H . G . Viiehe:
Iminium Salts in Organic Chemistry. Wiley-Interscience, New York
1976.
[2] For a review see C. Jutz in [I]. p. 225.
[3] Such reactions of nitriles are well-known: B. Stelunder, H. G. Viehe,
Angew. Chem. 89, 182 (1977); Angew. Chem. Int. Ed. Engl. 16, I89
(1977); J . Liebscher, H . Hurtmunn, Collect. Czech. Chem. Commun.
41, 1565 (1976).
[4] J . Perronet, A . TechP, J . Chem. Res. (S) 1978, 43.
BOOK REVIEWS
Einfuhrung in die Pharmazeutische Chemie (Introduction to
Pharmaceutical Chemistry). By 0.E. Schultz. Verlag Chemie,
Weinheim 1978. xvi, 460 pp., 15 figs., 83 tables, bound,
DM 56.00.
New textbooks on pharmaceutical chemistry are welcome,
since there are not many of them in German. As is appropriate
for an introduction, the author has made a representative
selection of the most important pharmaceuticals. The book
is divided into six sections : Central Nervous System, Peripheral
Nervous System, Disinfectants, Substances for the Chemotherapy of Infections and Cytostatics, Organs, and Vitamins. Each
chapter in these sections is introduced by a brief pharmacodynamic or biological characterization of the group of pharmaceuticals, at times with notes on the action mechanism or
on structure-activity relationships. This is followed by a tabular
summary of the substances with tradename, chemical name,
formula, and international abbreviation; next come synthesis
or source (natural products), qualitative tests (identity and
purity), and quantitative determination, together with data
on activity and application.
Even though it is assumed that the reader has some basic
chemical knowledge, reference to the classical reactions of
organic chemistry (e.g. named reactions) is often missing,
as to a certain extent is the clear application of the concepts
of tautomerism and resonance. There is a note in the foreword
stating that in the analytical sections the procedures and
requirements of DAB 7, EuPharm, and some other national
pharmacopeias have been taken into account; nevertheless,
detailed information should still have been given in the text.
In the same way, notes on the areas of agreement and disagreement between the pharmacopeias mentioned would have been
desirable. Further important aspects of pharmaceutical
chemistry are the stability of pharmaceuticals and pharmacokinetic parameters; the latter could stimulate the synthesis
of derivatives.
334
The development of pharmaceutical chemistry from a collection of random observations to a system of systematic research
is not taken into account, though from the didactic viewpoint
this is just as important as the listing of research workers
who have made fundamental contributions to this multidisciplinary field of research. This type of information could have
been included as footnotes or in a table.
There are also some inorganic pharmaceuticals (e.g. lithium
carbonate) that have not been mentioned. In addition (and
this is possibly due to the structure of the book), some important groups of pharmaceuticals get too short a mention (e. g.
anticoagulants) or no mention at all (e. g. analeptics, pentetrazole).
The style of the book is good; the few errors in structural
formulae could easily be corrected in a later edition. The
over-all impression is that this “Introduction” has successfully
extended the range of textbooks in the field of chemistry.
K . E. Schulte [NB 462 IE]
Transient Techniquesin Electrochemistry. By D. D. MacDonald.
Plenum Press, New York-London 1977. 1st edit., xii, 329
pp., numerous illustrations, bound, $45.00.
This book deals with the relaxation phenomena that may
be observed at the electrodes of galvanic cells as the voltage
or current changes with time. Since one can specify either
the current or the voltage as external parameters in a large
number of ways, a variety of experimental techniques has
sprung up, so that it is difficult even for the expert to remember
them all. In this book the author gives an ordered presentation
of such techniques, and in particular chronoamperometry,
chrono-potentiometry, cyclic voltammetry, and alternatingcurrent methods. He places special emphasis on an explanation
of the mathematical principles for the analysis of the reaction
couplings that lead to relaxation phenomena. A good summary
of the expected time lapses is provided, and this will prove
Angew. Chem. Int. Ed. Engl. 18 (1979) N o . 4
0 Verlay Chrmie, CmbH, 6940 Weinheim, 1979
0570-0833/79G404-0334 $ 02.50/0
very helpful to readers wishing to familiarize themselves with
theoretical deviations.
The final aim of such studies is to obtain information on
the mechanism of the electrode reactions concerned from
the analysis of the relaxation process. However, the book
is not very helpful in explaining which method is most suitable
for a specific purpose. The techniques are arranged one after
the other without any evaluation. One of the most effective
techniques, the current-pulse method (coulostatic method)
is not even mentioned. Practical examples are rare. The book
is suitable for readers who enjoy clear mathematical derivations and who already have practical experience, or who are
prepared to turn to other sources for advice.
Heinz Gerischer [NB 452 IE]
Biochemistry-The Chemical Reactions of the Living Cell.
By D. E. Metzler. Academic Press, New York 1977, xxxii,
1129 pp., bound, $ 24.95.
The simple anatomical classification of physiological
chemistry-chemistry here, metabolic chains there, and one
or two appended chapters on hormones, body fluids, and
organs--was a historical consequence of its predominantly
medical alignment. General biochemistry appeared as biology
became more and more aware of its chemical basis and the
dynamic nature of the body’s building blocks. It culminated
in the clever idea of Fruton and Simmonds that proteins (as
biocatalysts) should be the central teaching point, with physicochemical considerations and the structure and metabolism
of other biological molecules grouped around them. The more
successful of their followers hardly changed this principle
of a predominantly biological functional point of view, but
chose different aspects to emphasize. Thus, Lehninger made
energetics and Styrer made molecular information the main
theme, while Mahler and Cordes took as their starting point
the physical chemistry of cellular processes. In principle, it
is possible to break down the network of cellular organization
from many aspects. Each of these books, however, set a standard, and any new attempt must be measured against its
predecessors, although as far as the chemist is concerned
they all lack the chemical perspective. A comprehensive textbook, which is intended to lead biochemistry systematically
back to . chemical concepts, will therefore unavoidably be
regarded with critical curiosity.
Such an attempt has now been undertaken by Metzler
with his monumental work, and the goal is impressively well
achieved, for the author not only has available a wide range
of material but is also given authority by his own work in
the field of the transfer from chemical reaction models to
biological catalysis. Since the book is intended for readers
without much basic biological expertise, although it also makes
provision for the biologist, it starts with an introduction to
cellular structure, together with the fundamentals of molecular
energetics and subject-related thermodynamics (all data are
given in SI units). The interactions between biomolecules and
the internal organization of the cell are treated in detail,
and the characteristics of enzyme catalysis are discussed in
relation to the chemical reaction types, which are admittedly
rather limited“]. This knowledge is applied to a detailed description of themetabolic process. Optical analytical techniques
are accommodated in the chapter on photobiology. Nitrogen
metabolism has a chapter to itself; so d o biochemical genetics
[*] In connection with this I recall H . Meerwein’s disapproving comment:
How can you limit your interest to biochemistry if you want to be a proper
chemist? There is an air of monotony about the few reactions that are
found there: water in and water out; hydrogen out and hack in again ...
Keep well away from it. In contrast, how wide-ranging are the possibilities
of synthetic catalysis!
Anyew Chem. l n t . Ed. Engl. 18 (1979) N o . 4
and metabolic homeostasis. At the end of each chapter there
are study questions, some of them never likely to be answered.
The text is very attractively printed and easy ro read, vividly
supplemented by structural and reaction formulas, flowsheets,
and tables; anecdotal information in green-colored boxes
(shown in the same way in the table of contents) is added as
a spice to the basic blend.
It is unavoidable that even a system as well thought out
and consistently applied as this one should have its weaknesses.
For example, it has recently become easier to give a clear
chemical description of the role of selenium in metabolism,
and the reason why the respiration chain phosphorylation
cannot be chemically coupled in the given stoichiometry can
now be given more intelligibly; the principal criticism that
can be raised, however, is that today chemistry is capable
of more than bending electron arrows or perfecting nucleophilic and electrophilic attacks. Chemistry has become a highly
sophisticated extrapolating science, and I can see little sign of
it here. Why, for example, is cobalt suitable as the central
metal of vitamin B12; what is the reason for the structure
of the respiration chain (which has now been largely clarified);
what is the salient point of the chemical osmosis hypothesis
as against the “protonated membrane” hypothesis ; what
requirementsmust be met by a cofactor that takes up electrons
and protons simultaneously but separately; how can we link
molecular motion with the charge distrib.ution? And so it
goes on. But perhaps we are asking too much of a textbook
that is already very extensive; we really need a new medium,
allied to cinematography; words, even symbols, make everything static, two-dimensional, consecutive. However, what is
such nitpicking when applied to an attempt designed on a
grand scale, and in the final analysis so successful, which
also, because of the many and carefully collated literature
references, amounts to far more than a textbook? It would
be wonderful if the book not only met with acclaim among
chemists but were also used by biologists and introduced
them to the chemical foundations of biochemistry. Our comparison of textbooks can be summarized as follows: Stryer
for appearancelehninger for feeling-Metzler for understanding-but there is still no book on biochemistry that
meets all the requirements.
L. Juenicke [NB 460 IE]
Singlet Oxygen, Reactions with Organic Compounds and
Polymers. Edited by B. Rdnby and J . F. Rabek. John Wiley
& Sons, New York, 1978.1st edit., 331 pp., bound, f 15.00.
“Singlet oxygen” (lo2)
is the term used to describe two
short-lived and reactive electronic excitation states of oxygen
(302).
The present book contains 34 papers presented at the
EUCHEM conference on “Singlet Oxygen Reactions with
Polymers”, held in Sodergarn, Sweden, in September 1976.
A historical survey is followed by papers on the properties
of ‘02and on the spectroscopic determination and the deactivation of ‘02species in the gas phase. The greater part
of the book (16 papers, 187 pages) is devoted to the reactions
of ‘02in solution. The kinetics of the formation of ‘02
by energy transfer from electronically excited sensitizers to
302is the main point of two contributions.-BellG gives
an excellent survey on the mechanism and the rate constants
of the deactivation of ‘ 0 2by organic substrates (50 pages).
This topic is further discussed in two other short papers.
Attention should also be drawn to the review by Gollnick
(24 pages) on the reactions of ‘02with organic compounds.
This is followed by ten short papers (76 pages) on the photooxidation of selected compounds.
The last third of the book (14 papers, 114 pages) deals
with the reactions of polymers with ‘02and is introduced
335
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