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Book Review With Chemistry into the Third Millenium Opportunities in Chemistry.

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formed by intergrowth of ln5M01802H
and InhMoZZ014
layers in the ratio 1 : 1.
The number of Mo-Mo bonding states can be estimated
by suitable fragmentation of the oligomeric cluster into
Mo,OI-.+ ( n - I)Mo,O,.’~ Accordingly, one expects, besides “homogeneous structures” (i.e. structures with a single type of layers), also structures with clusters of other
lengths. A first confirmation of their existence was provided by high-resolution transmission electron microscop ~ . ~ ’Figure
]
2a shows the alternating sequence of cluster
layers in an I n , IMo4006Z
crystal fragment. The thicknesses
of the layers are 1300 ((Mo,)~) and 1580 pm ((MO,)~),respectively; the difference corresponds exactly to the mean
length of an Mo,-octahedron edge (280 pm), and the sum
corresponds to the lattice constant, determined more
accurately by X-ray diffraction ( a =2887.8 pm), of
I n , IMo40062.Such alternating layer sequences occur in ordered regions of lo5 pm. In Figure 2a a section is intentionally reproduced in which stacking disorder is recognizable. The variation in the composition of the crystal
through two consecutive In5Moi80Z8layers is compensated by two immediately adjacent I~,MO,~O,,layers. In
the same sample, regions are found (Fig. 2b) that are exciusively made up of identical
layers over distances of lo5 pm. In the meantime, the respective new
compound In,Mo,
has been isolated as a homogeneous phase and has been characterized by X-ray crystallography (a=3160.8, b=948.9, c=983.9 pm).
Another crystal zone of the I n 3 M o , , 0 i , fragment is
shown in Figure 2c. In Figure 2d, an alternate stacking of
layers with (Mo& and the new (Mo,), clusters can be seen,
which, having regular sequences, likewise leads to the
composition In3Mo,,01,with the same translational period a=3160pm.
Thus, there is every indication of a similar diversity of
oligomeric clusters with edge-linked Mo, octahedra in the
case of oxomolybdates, like that already known in the case
of metal-rich chalcogenides with face-linked Mo,-octahedra.‘’’ Furthermore, there is the possibility of determining
the lengths of the polycations of main-group metals between the clusters via the lengths of the clusters.
Received. June 12. 1986 [Z 1814 IE]
German version. Angew Cbern 98 (1986) 831
CAS Registry numbers:
I n , , M04110h~r
103691-57-2; I n i M o , , O , , , 103980-72-9
[ I ] A. Simon, Angew. Cbem 93 (1981) 23; Angew. Cbem. In/. Ed Engl. 20
(1981) I .
[2] C. C. Torrdrdi, R. E McCarley, J . Am. Chem. Soc. l a / (1979) 3963.
[ 3 ] R. E. McCarley, K.-H. Lii, P. A. Edwards. L. F. Brough, J. Solid S/ate
Cbem. 57 (1985) 17.
141 H. Mattausch, A. Simon, E.-M. Peters, Inorg. Chem.. in press.
151 A. Simon, H. Mattausch, E.-M. Peters, 2. Kristallogr. 174 (1986) 188.
161 A. Simon in A. K. Cheetham, P. Day (Eds.): Inorganic Solids. Oxford
University Press, in press.
[7] R. Gruehn, W. Mertin. Angew. Cbem. 92 (1980) 53 I ; Angew. Chem. In/.
Ed. Engl. 19 (1980) 505.
[8] R. Chevrel, P. Gougeon, M . Potel, M. Sergent, J . Solid State Chem. 57
(1985) 25.
BOOK R E V I E W S
With Chemistry into the Third Millenium
Opportunities in Chemistry. Edited by: The Committee to
Survey Opportunities in the Chemical Sciences, National Research Council. National Academy Press,
Washington, D.C. 1985. vii, 344 pp.. bound, $ 24.15.ISBN 0-309-03633-X
This book, which has become known as the “Pimentel
Report,” is the outcome of a study endorsed by the US
National Research Council. A 26-membered “Committee
to Survey Opportunities in the Chemical Sciences” set u p
by the NRC has compiled, under the leadership of George
C. Pimentel and with the cooperation of more than 350 experts, a report documenting quite convincingly “the critical role played by chemistry in raising the quality of life,
meeting the needs of society, and contributing substantially to a nations economic strength”.“] The main aim of
the study was to answer the following questions:
-
What opportunities are there in chemistry?
How can chemists most effectively deploy the possibili-
[*] Cf. also C & EN, January 6, 1986, p. 2
846
ties of chemistry for the future economic well-being of
the community?
- How can we make the general public and their representatives in government aware of the importance of
chemistry in solving economic problems and in satisfying the needs of society?
- How can we best inform the politicians such that they
meet the correct decisions when granting financial support of research programs?
The experts who participated in this study come from all
areas of chemical research, from academic, industrial, and
national research institutes. The report is not meant primarily for the chemist but rather is directed at the interested
public and the scientific policy makers.
The areas of chemistry which could become increasingly
important in the future are outlined and used as a basis for
recommending a reassessment of priorities in research investment. Thus, it is expected that chemistry will play an
increasingly decisive role in the development of new processes and new materials in, inter alia, power supply, nutrition, hygiene, biotechnology, environmental protection,
and will help in maintaining the competitiveness of the
American industry and in contributing to the national security of the USA.
Angew. Chem. Inr. Ed Engl. 25 (1986) No. 9
Of particular interest to the scientist is the account of the
current state of chemical research and technology and the
developments to be expected in the innovative areas of
chemistry. These include, in particular, the following areas: chemical kinetics, theoretical chemistry, catalysis, synthesis, the chemical fundamentals of life, and analytical
methods.
From their account of the current state of and possible
fields of development in chemistry the authors derive,
from the American viewpoint, a number of scientific, industrial, and political recommendations, many of which
might also be relevant for other industrial nations, and not
least for the Federal Republic of Germany. The state of
competitiveness of US chemistry is carefully brought into
relief and attention is drawn to what other industrial nations are doing: thus, for example, it is pointed out that the
Max-Planck-Society in Mainz has founded a new Polymer
Institute.
This excellent work is concomitantly a concise account
of our present chemical knowledge and, as such, also an
avowal to research and industrial progress: “Chemistry is
a central science that responds to societal needs” (P. 19).
The “Pimentel Report” provides a scientifically sound and
critical argument for all, who, despite the prevailing scepticism in our society, have faith in the future of chemistry.
Jan Thesing [NB 758 IE]
Merck, Darmstadt (FRG)
The Chemistry of Natural Products. Edited by R . H. 7homson. The Blackie Publishing Group, Glasgow 1985. xii,
467 pp., bound, L 46.00.-ISBN 0-412-00551-4
To produce a book about the progress made in the
chemistry of natural products in the last ten years is by no
means an easy task. The authors d o not claim to have written a comprehensive work, but are concerned rather with
giving an outline of progress in the main areas of the
chemistry of natural products. As the foreword makes
clear, the main emphasis in all the contributions is on
structure, chemistry and synthesis, but each chapter also
includes notes on biosynthesis. The book is divided into
nine chapters.
Chapter I (J. S . Brimacombe) deals with the chemistry of
carbohydrates. The applications of protecting groups are,
of course, discussed in detail here. This is followed by a
survey of the synthesis of sugars with antibiotic activity.
The reader is also given a compilation of natural products
syntheses which have employed sugars to transfer stereochemical information, and descriptions of some oligosaccharide syntheses. The chapter ends, with a survey of
structure determination in polysaccharides.
In Chapter 2, E. J. Thomas describes syntheses of aliphatic natural products. Syntheses of fatty acids and their
derivatives, of leukotrienes, marine natural products, pheromones, prostaglandins, polyether antibiotics, and macrolides are discussed in detail. The reactions described in
the text are illustrated by detailed charts, thus ensuring
that even very complex schemes are clearly presented. A
feature deserving special mention is the inclusion of lists
of review articles on each of the topics mentioned above,
which should help the user to find further literature in a
particular area.
In Chapter 3, T. J. Simpson has compiled information
Angenr. Chem. Int. Ed. Engl. 25 (1986) No. 9
on syntheses of aromatic compounds. For biosyntheses the
reader is referred to relevant books. Individual classes of
compounds are briefly dealt with in turn, including coumarins, chromanes, cannabinoids, butenolides, lignans,
flavonoids, naphthoquinones, ansamycins, and SO on.
Chapter 4, by J . R. Hunson, is a survey of terpenoids.
The terpenes are dealt with in order of increasing number
of isoprene units, and the chapter concludes with a short
section on carotenoids. Owing to the enormous number of
compounds it is not possible to give complete details of all
the syntheses and biosyntheses. Here too the reader is referred to review articles. An incidental point here is that
the reactants given under Scheme 12 ought to be included
in Scheme 14.
In Chapter 5, B. A . Marples gives a survey on steroids. A
general introduction is followed by sections on rearrangements, biomimetic syntheses, polyene cyclizations, and
more recent partial and total syntheses. Lack of sufficient
space has prevented some aspects from being treated in
detail, e.g. the synthesis of polyenes.
In Chapter 6 (B. W. Bycroft and A . A . Higton), aminoacids, peptides and proteins are discussed. If in addition to
their chemistry, the biochemical or biosynthetic aspects
had also been covered, it would have exceeded the limits
of such a chapter. The first section deals with various amino acids, with detailed descriptions of a small number of
syntheses. In the sections o n peptides and proteins too, the
presentation is mainly concerned with structural aspects.
Methods for sequence determination in peptides and proteins are touched on briefly. All the sections contain numerous references to biochemical studies.
The subject of Chapter 7, by I . R . C. Bick, is alkaloids,
which have been classified according to their biogenetic
origin. In this chapter the main emphasis is on synthesis,
but numerous references to the biochemistry and biosynthesis of the compounds are included.
In Chapter 8, J . B . Hobbs covers recent developments in
the area of nucleotide chemistry. The chapter begins with a
section on nucleosides (synthesis, reactivity and alkylation), followed by a similarly organized section on nucleotides. Three sub-sections are devoted to chirality at the
phosphorus atom. The final section of this chapter deals
with syntheses of nucleic acids and techniques for sequence determination.
In Chapter 9, A . H. Jackson deals with porphyrins and
related compounds. The emphasis is on synthetic methods,
together with a few digressions into biosynthesis. Following a section on porphyrins, chlorophylls and their analogs
are discussed. A comparatively large amount of space is
given to syntheses of Vitamin Bl2and related compounds.
The chapter ends with sections on bile pigments and prodigiosins.
The book is a very successful cooperative effort by the
various authors. It is not suitable as a beginner’s introduction to the chemistry of natural products, since it assumes
some specialist chemical knowledge, but because of the
wealth of information which it contains on each group of
substances it can be recommended for all research workers
in the field, and for scientists who wish to keep u p to date
in these matters.
The book is very attractively produced, and contains remarkably few misprints in the text or errors in the diagrams. It is worth the price.
Werner Angst [NB 744 IE]
Laboratorium fur Organische Chemie der
ETH Zurich (Switzerland)
847
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