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Book Review Chemical and Biological Generation of Excited States. Edited by W. Adam and G. Cilento

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dence for this is provided by the spectrum at 340 K. In accord with the shift in equilibrium in the direction of
EtMgBr13.”1,an average signal is found at 6 = 54. Since the
equilibrium constant for the methyl compound MeMgBr
K -30[”1 is larger than that for EtMgBr (K=5.1)[31, 3 displays an averaged signal (6=67.8), even at 300 K.
In the case of CpMgBr 9, the ”Mg signal is further removed from that of MgBr, and the line width is narrow
enough to allow the Schlenk equilibrium to be studied
quantitatively. Signals at 6 = 16.3 (1-2% 6) and at
6 = - 26.8 ( =98% 9 ) are observed for 1.38 M solutions of 9
in THF. The same chemical shifts and line widths are
found when Cp,Mg and MgBr2 are mixed in the ratio 1 : 1
in THF. The signal intensities allow a value for the equilibrium constant to be estimated which is in good agreement
with the value ( K = 10s)[’21obtained by extrapolation to
298 K.
In comparison with ‘H- and I3C-NMR spectroscopyl10,11,131 , 2
5 g-NMR
~
spectroscopy has considerable advantages in the study of the Schlenk equilibria, since all
three species can be recorded and identified directly from
their typical chemical shifts. The large range of ”Mg
chemical shifts (ca. 200 ppm) permits unequivocal statements to be made about the bonding behavior such as, e.g.,
in 17 and 2.
Received: March 5 , 1984 [Z 741 IE]
German version: Angew. Chem. 96 (1984) 521
CAS Registry numbers:
1, 557-18-6; 2, 69219-07-4; 3,75-16-1; 4,925-90-6; 5, 1730-25-2; 6,7789-48-2;
7, 14024-56-7; 8, 90858-32.5; 9, 34766 86-4; 12, 90858-33-6; 13, 90858-34-7;
14, 90858-35-8; 17, 1284-72-6.
[I] a) S. Forsen, B. Lindman in R. K. Harris, B. E. Mann: NMR and the Periodic Table, Academic Press, New York 1978, p. 183; b) S. Forsen, B.
Lindman, Annu. Rep. NMR Spectrusc. I I A (1981) 183; c) Fruitless attempts to study organomagnesium compounds by ”Mg-NMR studies
have been reported: F. Toma, M. Villemin, M. Ellenberger, L. Brehamet,
Proc. X V I Colloq. AMPERE 1970. 317; d) A broad ”Mg-NMR signal
for ethylmagnesium halides has been observed: C. Brevard, P. Granger
in Handbook of High Resolulion Multinuclear NMR, Wiley, New York
1982, p. 96.
[2] H. Lehmkuhl, Bull. SOC.Chim. Fr. I! 1981, 87.
[3] E. C. Ashby, Q. Rev. Chem. Soc. 21 (1967) 259.
[4] The 6(25Mg)value of this standard is largely independent of the concentration and the H 2 0 / D 2 0 ratio (L. Simeral, G. E. Maciel, J. Phys. Chem.
80 (1976) 552). Different solvents were corrected from their 2H-NMR
signals, e.g. 6(2H, standard)=4.15 and 6(THF)=3.58. Instrument:
Bruker WH400 spectrometer with a multinuclear 10 mm probe (90”
pulse: 40 ps). Typical recording times were a few minutes.
[S] Cryoscopically in benzene.
[6] W. Bunder, E. Weiss, J . Organomel. Chem. 92 (1975) 1.
[7] A. Haaland, J. Lusztyk, J. Brunvoll, K. B. Stdrowieyski, J. Organomet.
Chem. 85 (1975) 279.
[S] K. Faegri, J. Almlof, H. P. Luthi, .J. Organomel. Chem. 249 (1983) 303.
191 S. Evans, M. L. H. Green, B. Jewitt, A. F. Orchard, C. F. Pygall, J . Chem.
Soc. Faraday Trans. 2 1972, 1847.
[lo] M. Stahle, M. Schlosser, Angew. Chem. 92 (1980) 497; Angew. Chem. Int.
Ed. Engl. 19 (1980) 487.
1111 D. F. Evans, G. V. Fazakerley, J . Chem. Sue. A 1971, 184.
[I21 W. T. Ford, J. B. Grutzner, J . Org. Chem. 37 (1972) 2561.
[13] G. E. Parris, E. C. Ashby, J . Am. Chem. Soc. 93 (1971) 1206.
BOOK REVIEWS
Chemical and Biological Generation of Excited States.
Edited by W. Adam and G . Cilento. Academic Press,
New York 1982. xi, 388 pp., bound, $ 59.50.
The first seven chapters of this book give a detailed survey of the diverse aspects of the generation of excited
states in chemical systems. Several sections are devoted to
the chemistry of dioxetanes, covering the topics of synthesis, chemical characterization, activation (chemi- and photoenergization) and photophysical and photochemical
transformations of the excited states. A critical and systematic survey of the techniques for their detection and calculation of excitation yields is presented. Without losing in
originality, the chapter by W. Adam offers a useful and
comprehensive introduction to the chemistry of dioxetanes, which enables the reader to go easily over other topics treated in this book. In addition, the activation parameters of over 50 well-studied 1,2-dioxetanes are summarized. In general, the chemical reports on these four-membered ring peroxides are sustained by common basic concepts that permit the reader to establish rapid comparisons, e.g., evaluation of dioxetane chemiluminescence in
solution and in the gas phase. Solution-phase chemiluminescence resulting from electron-transfer reactions (electrochemiluminescence) is analyzed here on theoretical basis, and mechanistic implications for the production of the
emitting state and experimental techniques are presented.
These accounts on the chemistry of some excited states
(mainly concerned with excited carbonyl compounds derived from dioxetane energization) give a synopsis of genAngew. Chem. In[. Ed. Engl. 23 (1984) No. 7
eral and important concepts without being simplistic or
falling into a long listing of observed details. They provide
valuable up-to-date information for the chemist or biologist interested in the generation of excited states.
The final four chapters treat the generation of excited
species in biological systems. The possible formation of
singlet oxygen in some enzymatic reactions is discussed
along with a short examination of the processes that can
mimic singlet oxygen. At variance with the native chemiluminescent systems, the fluorophor-mediated chemiluminescence is also considered and the advantages of the use
of such chemiluminigenic probes in the study of biological
oxidations are listed. However, the disdavantages inherent
in the addition of a foreign compound to a biological system are not taken into account. An outstanding contribution is the chapter on “Electronic Excitation in Dark Biological Processes”. The author, G . Cilento, and his team
have long been committed to a systematic study of the production of excited molecules which give the cell the potentialities of photochemistry in the absence of light. The section deals with the occurrence and generation of excited
states and puts forward their role in biological processes.
The possibility that one of the roles of peroxidases and
some internal monooxygenases might be the formation of
an electronic excited state product is exploited here on
sound experimental grounds. N o doubt the biologist could
feel himself attracted to the discipline of “photobiochemistry in the dark” after these serious attempts for its characterization and definition.
535
In summary, the book gives an up-to-date account of the
field and can be recommended to those interested in the
occurrence of excited states in chemistry and biology.
Enrique Cadenas [NB 622 IE]
Institut fur Physiologische Chemie
der Universitat Dusseldorf (FRO)
Vitamin BIZ. Vol. 1: Chemistry; Vol. 2: Biochemistry and
Medicine. Edited by D . Dolphin. Wiley Interscience,
Chichester 1982. xiv, 677 pp., bound/xiv, 505 pp.,
bound, together E90.00.
This two-volume work, which is the most comprehensive
up to now covering vitamin BIZ,fulfills its claim to cover
the chemistry, biochemistry and medicine of this group of
compounds. It has been possible to recruit leading scientists for each of the topics to which a chapter is devoted.
Volume 1 with almost 600 pages of text is devoted to
chemistry. A historical introduction (Folkers) and a summary of the nomenclature (Cohn) are followed by an extensive third chapter (84 p.) by J. Pickworth-Glusker devoted
to the structures of corrinoids and containing a wealth of
data not all of which had previously been published. The
numerous tables and figures and the detailed discussion
concerning structure-activity relationships make the few
slight errors on p. 77 and 78 seem unimportant. The impressive advances made recently are described by Buttersby
and McDonald in a fascinating chapter on the biosynthesis
of the corrin macrocycle. In chapter 5 there follows the
biosynthesis of the cobalamine coenzyme (Huennekens et
a].). The chapter on “The total synthesis of Vitamin Bt2”
by Stevens which is obligatory for any book on the subject
presents this complex project, which has been the subject
of previous reviews, in a very informative manner. The
long needed summary of the rich chemistry of the corrin ligand by Bonnett is just as useful; here too, results are
quoted that were until now only available in dissertations.
Then follow two chapters concerning the synthesis ( K . L.
Brown) and reactivity (Hogenkamp) of organocobalt complexes. Chapters 10, 14, and 15 are particularly devoted to
the central theme of coenzyme BIZchemistry, the reactivity
of the Co-C bond. Chapter 10 by Pratt, engagedly and
colorfully written, is detailed (68 p.) and contains an attempt to formulate a basic unified mechanistic view of the
vitamin B,,-dependent isomerases that is not completely
established and unchallenged in all aspects. Chapters by
Halpern and by Colding close the first volume with discussions of the models and theories for coenzyme BIZ catalyzed reactions. Chapters 11 (Giunnotti: UV/VIS, CD,
MCD), 12 (Pilbrow: ESR), and 13 (Williams et al.: NMR),
which contain many data which had previously been scattered throughout the literature or were unpublished, are
somewhat arbitrarily interposed between the contributions
on the above range of topics.
The second, smaller volume covers biochemistry and
medicine. Chapter 5 on metal-free corrinoids (Koppenhagen) is rather misplaced here and it would have been better
to include it in the first volume. The “medical” chapters
1-4 (Beck, Bradbeer, Nexe and Olesen) which cover intrinsic factor, cobalamine transport and determination are
easily readable and understandable for an organic chemist.
A short informative chapter (15 p.) on methyl transfer
reactions (J. M. Wood) is followed by one concerned with
a discussion of acetate biosynthesis which goes beyond the
536
bounds of corrin chemistry, by Ljungdahl and H. G. Wood.
The second half of the volume contains seven detailed
treatments of coenzyme B,2-catalyzed enzyme reactions.
The common “design” (history, sources, isolation, measurement o f the enzymes’ activity; substrates and mechanism of the enzyme reaction) is enriched by the varied
presentations of the authors (Baker and Stadtman, Toraya
and Fukui, Babior, Switzer, Taylor, Retey, Blakley). The
possibly unavoidable repetition of material already presented in chapters 9, 10, 14, and 15 of the first volume is
not too disturbing.
Both volumes contain detailed subject and author indexes. The quality of the illustrations and the print is very
high; the price is high but reasonable in comparison with
similar works. These books can be highly recommended;
not only are they a “must” for every scientist working in
the vitamin BI2 field but are also important, for example,
for chemists dealing with organometailic compounds,
bioorganic chemistry, or heterocyclic natural products.
Apart from the well-done presentation of the “state of the
art”, the importance of this work lies in the fact that the
many controversies and “unwritten chapters” in this long
and intensively studied field are brought before our eyes.
Engelbert Zass [NB 637 IE]
Laboratorium fur Organische Chemie der
Eidgenossischen Technischen Hochschule Zurich
Ullmanns Encyklopadie der technischen Chemie. Edited by
E. Bartholomi, E. Biekert, H . Hellmann, H . Ley f . W. M .
Weigert f . and E. Weise. Verlag Chemie, Weinheim
1983. 4th Edition. Volume 23, Textilhilfsmittel bis Vulkanfiber. xv, 750 pp., bound, DM 545.00.
With the publication of the 23rd Volume of the 4th Edition of Ullmann’*]only one further volume and the general
index are required to complete the series. This means that,
on average, two volumes per year have been produced, a
marvellous performance on the part of the editors and
publishers, which is the more imposing if one takes the
trouble to ascertain the number of authors involved in the
production of a single volume. There were more than 80
for this volume.
Once again the sub.jects included in the volume are
drawn from every area of industrial chemistry; that is,
from inorganic chemistry: thallium, thorium, titanium, vanadium, and uranium together with their alloys and compounds, then the transuranic elements (excepting plutonium which is discussed in its own right in Volume 18) and
some inorganic sulfur compounds (thiocyanic acid and
thiourea); from organic chemistry come: vinyl compounds,
toluene, toluidines and a range of organosulfur compounds (thiazoles, isothiazoles, benzothiazoles, organic
thiocyanates and isocyanates, thioles, sulfides, polysulfides, thioglycolic acid, thiophene and benzothiophene);
from application technology come: textile additives (102
p.), nonwovens, inks and other writing fluids, separating
agents, drying agents, drying oils; from the area of raw materials come: composites, clay and clay minerals, pottery;
then vitamins (108 p.), veterinary medicines, tri- and diarylmethane dyestuffs, peat. Then come two articles of particular topicality, namely thermo- and photoelectricity
(28 p.) and the saccharification of starch and cellulosecontaining materials (42 p.). Both these articles are concerned with topics touching on possible future forms of en[*] Cf. Angew. Chem. Int. Ed. Engl. 23 (1984) 255.
Angew. Chem. Int. Ed. Engl. 23 (1984) No. 7
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