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Book Review The Electronic Structure and Chemistry of Solids. By P. A. Cox

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R
-
OH
-%
2
1
ee, respectively, in the usual work-up.[' '- "I. We attribute
the high optical induction obtained with the mixture of
4b/5b, to the component 5b, which represents a functionalized PROPHOS."31
Experimental
3
A
PPh,
OH
4
5b
Scheme I . a, R = P h : b , R=nPr. a) Ti(OiPr),, tBuOOH, diethyl tartrate,
CH.C12, -70°C. 3 h. h) p-tosylCI, pyridine, - I O T , 20 h. c) LiPPh>, THF,
20°C. 2 0 h.
The ring-opening of epoxides with strong bases occurs
stereospecifically with inversion. However, it may take
place at carbon atoms C-2 and C-3, respectively, resulting
in a mixture of products. The site of nucleophilic attack
can be controlled by steric and electronic effects.['.
We
found, that the reaction of 3a with LiPPhz is regiospecific,
giving exclusively 4a. In the reaction of 3b with LiPPh2,
however, we isolated a 2.5 : 1 mixture of 4 b and 5 b . All
efforts, to separate 4b and 5 b were unsuccessful.
The tosylates 3a and 3 b were recrystallized three times.
Therefore, we assume that 4a and the components of 4b/
5 b are optically pure. At present, most of the optically active diphosphanes are only accessible in multi-step procedures.[" The new synthesis presented in this communication is short, operationally simple, and easily employed on
a large scale and with a variety of substitution patterns.
Moreover, the hydroxy group in 4 and 5 formed upon
epoxide ring-opening is suitable for further derivatization.
4a and 4b/5b served as chiral ligands in the
[Rh(cod)CI],-catalyzed enantioselective hydrogenation of
(a-a-acetamidocinnamic acid with 1.1 bar H2 in methanol
solution at room temperature. With RhAigand ratios between 1 : 1.05 and 1 : 1.10 and Rh/substrate ratios of 1 :50
the hydrogenation is quantitative within 3 hours. 4a and
4b/5b gave ( R ) - ( -)-N-acetylphenylalanine in 54 and 83%
3a: The epoxidation of cinnamyl alcohol la was carried out as described 171
to give 2a in 55O/u yield, 93% ee, containing 15% unreacted l a . The pale amber, oily 2a (6.1 g, 40.6 mmol) was tosylated with p-toluenesulfonylchloride
(7.75 g, 40 7 mmol) in 40 mL of pyridine at - 10°C. After 20 h the mixture
was filtered, the filtrate concentrated, treated with 5 0 mL of I M H?PO, and
extracted three times with 50 mL CHICI,. Crystallization of the yellow oil
from etherlhexane gave 3a as colorless crystals: yield 8.6 g (70uh) M.p. 6869°C. [a],,=-45" ( ~ = 2 . 5 ,CHCI?). ' H - N M R (250 MHz. CDCI,): 6=7.347.82 (m, 4 H . AA'BB'), 7.27 (5, S ) , 4.10-4.36 (m, 2). 3.70 (d. IH, J = 2 Hz),
3.10-3.30 (m, 1 H), 2.45 (s, 3 H).
4a: 8.4 g (27.6 mmol) of 3a were dissolved in 100 mL of T H F and added to a
solution of LiPPh? in 50 m L of THF, prepared by reaction of 10.5 g (56.4
mmol) HPPhz and 34.5 m L of a solution of BuLi in hexane ( 1 . 6 4 ~ ) .After
20 h stirring at room temperature, the mixture was hydrolyzed by addition of
100 m L of acetate huffer (pH 5.1). The aqueous phase was extracted with
three 50 mL portions of ether. The combined organic layers were dried over
Na2S04, filtered and concentrated to give a pale yellow oil, which crystallized o n trituration with cold methanol. Recrystallization from toluene/heuane gave pure 4a as a colorless powder: yield 9.Og (65'bo). M.p. 142 143°C.
[a],,= -74" ( c = 1.0, CHCII). CI-MS (isobutane): ni/z 505 (MH"). ' H - N M R
(250 MHz, CDCI,): 6=7.03-7.57 (m, 25H), 3.85-3.93 ( m , 2H), 2.01 -7.17 (m.
3H). "P-NMR(101.257 MHz,CDCI,):6=-5.8(d, I P, J = 2 Hz), -20.0(d.
1 P, J = 2 Hz). "C-NMR (22.64 MHz, CDCI,). 6 = 127.0-138 0 (m), 68.9 (dd,
IC), 51.3 (dd, IC),35.9(dd, IC).
Received: January 2X. 1988 [Z 2595 IE]
German version: Anyeu. Chem. 100 (1988) 7 3 0
CAS Registry numbers:
1a.4407-36-7; 1b.928-95-0: Za, 104196-23-8: 2b. 89321-71-1;3a. 114395-16-3:
3b, 114395-17-4: 4a, 114422-48-9; 4b, 114422-49-0; 5b, 114395-18-5.
[ I ] H. Brunner, J. Kraus, J Mol Catal.. i n press.
[2] H. Brunner, Top. Stereochem. 18 (1988).
[3] a) J. D. Morriaon (Ed.). A.qmmerrrr Sjnthecis Vol. 5. Chirul C u t u / i ~ . ~ i . ~ ,
Academic Press, New York 1985: h) H B. Kagan in p a ] , p. I .
[4] B. E. Rossiter in [3a], p. 193.
[5] M. G. Finn, K. B. Sharpless in [3a], p. 147
161 A. Pfenninger, S.vn/hesis (986, 89
[7] R. M. Hanson, K. B. Sharpless, J . Ory. Chem. 5 / (1986) 1922.
[ 8 ] J. G. Hill. K. B. Sharpless, C. M. Exon, R. Regenye, O r y . Sivirh. 63
(1984) 66.
191 C. H. Behrens, K. B. Sharpless, Aldrichiniicu Acta 16 (19x3) 67
[lo] K. B. Sharpless, C . H. Behrens. T. Katsuki, A. W. M. Lee, V. S. Martin,
M. Takatani, F. J. Walker, S. S. Woodward, Pure Appl. Cl7em .75 ( 1 9 8 3 )
589.
[ I I ] H. Brunner, W. Pieronczyk, J . Chem. Rer S j n o p . IY80. 76: J . Cheni.
Res. Miniprinf 1980. 1275.
[I21 H. Brunner, W. Pieronczyk, B. Schonhammer, K Streng, I . Bernal, J.
Korp, Chem. Ber. 114 (1981) 1137.
1131 M. D. Fryzuk, B. Bosnich, J . A m . Chem. Sot..99 (1977) 6262.
BOOK R E V I E W S
The Electronic Structure and Chemistry of Solids. By P. A
Cox. Oxford University Press, Oxford 1987. 259 pp., paperback, .X 12.50.-ISBN 0-19-855204-1
Solid state research is in vogue. New high temperature
superconductors, conducting organic polymers, "heavy
fermions", charge and spin density waves-interdisciplinary groups have achieved these and many other advances
and discoveries in this field in very recent years. Surface
science-a field with close links to both chemistry and
physics- has also experienced an explosive growth during
A n y r u . Cheni 111, Ed EIXJI. 27 (19881 N o 5
the past decade. One result of these developments is the
necessity for communication in interdisciplinary fields,
since many of the electronic properties of solids are now of
interest not merely to a small circle of specialists but also
to synthetic chemists. Although there are excellent textbooks available o n solid state physics, such as Kittel's "Introduction to Solid State Physics" and "Solid State Physics" by Ashcroft and Merrnin, these standard works, written by physicists for physics students, are not very attractive to chemists for two reasons: first, the presentation of
the material is often too mathematically advanced, and
7 I9
second, the examples chosen are kept very simple and are
therefore not of much interest to the chemist who is more
concerned with complex substances and structures.
There is quite obviously a gap here, which the present
book, derived from a series of lectures to advanced students at the University of Oxford, sets out to fill. In its
conception it follows in the steps of the now rather dated
“Seven Solid States” by W. J. Moore, which in its time familiarized chemists with basic solid state physics, using
suitably chosen compounds as examples.
In the first three chapters of the book, basic concepts
such as bonding situations in crystals, the free electron gas
and optical processes are treated qualitatively and without
giving mathematical derivations, illustrated by appropriate
examples. Some spectroscopic techniques are outlined as
well, with particular emphasis on photoelectron spectrosCOPY.
The remaining four chapters deal with special topics. An
entire chapter is devoted to a “formal” introduction to energy band theory. The concepts needed for the analysis of
band structures are worked through with the help of diagrams, without giving involved mathematical derivations,
and are tested on simple examples such as graphite and
ReO,. This is followed by a short account of the experimental determination of band structures using angularly
resolved photoemission spectroscopy. Two further chapters deal with electron repulsion effects in terms of the
Hubbard model, and with lattice distortions and mixed
valency compounds. The final chapter is concerned with
semiconductors and their uses in photovoltaic cells, transistors etc.
Altogether the conception of the book and the way in
which it has been put together make it a useful addition to
the literature. The material is arranged in a clear manner,
and the individual sections are lucidly written and illustrated by many well chosen examples. Some of the topics
are discussed only briefly, but one cannot expect a book of
250 pages to cover every topic of current research in detail.
The material included has been well chosen. The references to more detailed review articles and original papers
which are included, with comments, at the end of each
chapter give the interested reader easy access to further
reading, and a short formula index included at the end of
the book helps in locating compounds cited as examples.
In summary, the author P. A . Cox has brought considerable skill to the task of familiarizing chemists with the electronic structure of solids. At the very attractive price of
-E 12.50 in its paperback edition, the book is certainly a
worthwhile and useful aid to advanced students and to
synthetic chemists.
Wolfgang Tremel [NB 871 IE]
Anorganisch-chemisches Institut
der Universitat Miinster (FRG)
Symmetry through the Eyes of a Chemist. By I. Hargittai
and M . Hargittai. VCH Verlagsgesellschaft, Weinheim
1986. xii, 458 pp., bound, DM 156.00.-ISBN 3-52726409-4
I spent the years 1950-51 in Linus Pauiing’s group at the
California Institute of Technology, which was then one of
a mere handful of Meccas for theoretical chemists. TOgether with Sidney Weinbaum of HT fame (he was-to my
knowledge-the first to use an extended basis in a MOcalculation), I was assigned the task of calculating carbon
clusters C, by the then popular valence bond method. We
720
met our Waterloo as soon as we reached the cubical CH
cluster, not knowing how to factorize the general eigenvalue problem of order 14 into manageable parts. (Those
were still the days of the B.C. era, i.e. before computers,
even at Caltech.) There was nothing to be ashamed of,
since we were in the best of company in our lack of knowledge. Indeed, even in most books on quantum chemistry
written for “real” chemists, group theory was conspicuous
by its absence. Even in Streitwieser’s classic on MO theory
written in 1961, symmetry considerations play at best only
a Cinderella role.
The situation has changed dramatically since those days.
The enormous growth in the use of physical methods, especially spectroscopy, the wide application of quantum
mechanics and of a new chemical language derived from
it, and the discussion of reaction mechanisms and stereochemical problems in terms of symmetry, have led to a
rapid increase of interest in symmetry and group theory.
Chemists changed their outlook and began to collect
Escher prints, and publishers started to outbid each other
in producing introductions to these new fields. One consequence of this is that there is now scarcely a single library
which owns a more than half complete collection of all
books relating to this area, ranging from advanced mathematical works to those of a popular scientific type. Every
newly published book on this theme must therefore be
judged against this background of an overabundance of related literature which already exists.
The first thing which strikes one about the book reviewed here is its exorbitant price: a princely DM 156.for a book which is presumably intended as an introduction. One might therefore ask why the book is so highly
priced, and whether this could not have been avoided. One
cause of this is a use of space which could scarcely be rivalled in its extravagance. With an approximate page format of 24 cm x 17 cm=408 cm2, the print area is only
about 21 cm x 9 cm = 189 cm’. Admittedly the extremely
wide margin-about double the usual width-is partly
used for figure legends, but these generally only contain
information on the sources for the figures, e.g. the caption
“Photograph by the authors”, which is repeated about 40
times. The 421 literature references occupy three times as
much space as they would in other books, owing to the
very large gaps between individual references, allowing
only 15 to a page. In addition the number of examples included is wastefully large, many of them scarcely adding
anything to the understanding of the material. Or d o you
believe that the concept of antisymmetry will be made significantly clearer to a novice by having before him a picture showing a McDonald’s adjacent to a more up-market
restaurant? (“Photograph by the authors”). Likewise
“Eszter Hargittai in front of a shop window (1980) (“Photograph by the authors”) makes only a minimal contribution to the understanding of mirror symmetry. Altogether
one gets the impression that the authors have tried, in their
understandable enthusiasm for the subject, to include in
this book every quotation related to symmetry which they
have collected over the years. As a result there are loilg
sections which are more like a family album of personal
recollections than a guide through the subject written with
the object of instructing the reader. Further, the information content is sometimes appallingly thinly spread. For
example, seven pages are needed to explain what a matrix
is and how two matrices are multiplied, and ten pages to
discuss the symmetry properties of the HMOs in benzene.
Dietrich Stauffer, in his excellent and wittily written book
“Introduction to Percolation Theory”, writes: “YOU may
Angew. Cliem. Inr. Ed. Engl. 27 /19XX/ N o . 8
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