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Book Review Chromatographisches Praktikum (Practical Chromatography). By G. Hesse

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shown, together with two unidentified products (8) and ( 9 ) .
Use of maleodinitrile afforded the same compounds, yields
being 88.7, 2.2, 1.2, 2.1, 3.0,and 2.8% [for ( 8 ) + (9)I. respectively. This can be explained only by assuming an intermediate stage that permits rotation. Since ( 3 j - ( 7 ) , as well
as fumaro- and maleo-dinitrile are stable under the reaction
conditions and a zwitterionic intermediate was previously
excluded, the intermediate product must be the diradical
(10). The question whether the olefin approaches the bicyclic system from “below” (a) or “above” (b) could be
answered by studying addition of maleic anhydride to [2,3D2]bicyclo[2.1.0]pentane ( I ) ; the olefin approaches from
“below”. / J. Amer. chem. SOC.90, 4746 (1968) / -Kr.
[Rd 940 IE]
o n Pyrex glass were less than 10%. Polyethylene containers came off best when the sea water was acidified to
p H = 1.5; then, after 20 days, only about half of the scandium had been adsorbed, while the amounts for other
elements were less than 10%. / Analyt. Chim. Acta 42, 533
(1968) / -Kr.
[Rd 937 IE]
Bis(triphenylstanny1)mercury (1), the first compound containing a Hg-Sn linkage, was obtained by C. Euborn, A . R.
Thompson, and D . R . M. Wulton, as a yellow solid, o n treatment of triphenylstannane with bis[bis(trimcthylsilyl)aniidolmercury at room temperature:
2 (C6Hd3SnH
+ Hg”(Si(CH3)3)~12
+
+
H~[S~(C~HS2
) ~[(CH3)3SilzNH
~Z
The adsorption of trace elements from sea water o n to the
surface of containers has been studied by D . E. Robertson for
the radioactive isotopes 46Sc, 59Fe, 6OCo. 65Zn, W r , 86Rb,
IIoAg, 114111, 124Sb, 134Cs, and 235U, when these are added to
the sea water as soluble salts. After storage for 20 days a t the
normal p H (8.0) of sea water in polyethylene flasks, indium,
scandium, and iron were adsorbed to the extent of about 95.
45. and 40%, respectively; losses of the other elements remained below 20%. Except for scandium and iron, the losses
(0
( I ) is stable for several months in the dark a t room temperature, but decomposes rapidly in light, in solution, or when
heated. The Hg-Sn bond is not formed from triethylstannane and dibenzylmercury at 100OC or from bromotriphenylstannane and sodium amalgam, the analogy to Hg-Si
and Hg-Ge bonds failing. / Chem. Commun. 1968, 1051 /
-Kr.
[Rd 938 IE]
BOOK REVIEWS
Chromatographisches Praktikum (Practical Chromatography). By G . H e a e . Vol. 6 in the series “Methoden der Analyse in der W m i e ” (Methods of Analysis in Chemistry)
edited by F. Hecht, R. Kaiser, H . Kriegsmunn, and W.
Simon. Akademische Verlagsgesellschaft, FrankfurtiM.
1968. 1st Edit., 1967, 244 pp., 50 figs., 28 tables, linen.
D M 39.-.
This book gives a n introduction to the most important
chromatographic procedures and describes in the two main
chapters the chromatography of solutions (column, thinlayer, and paper chromatography) and gas chromatography.
The above procedures and their variants are described with
the aid of numerous easily reproducible examples. The author
addresses himself predominantly to chemistry and biology
students in their final year at school or the first year a t university. The comprehensive presentation of chromatographic
methods and the emphasis laid o n their essential similarity
are particularly welcome. Theoretical explanations are only
given insofar as they are necessary for the solution of examples. Anyone who has worked through the experiments
should have n o difficulty in solving problems of separation
in analogous cases.
With this selected class of readers in mind, it is of course
understandabIe that various methods important in research
(such as exchange chromatography of amino acids and
nucleotides, countercurrent distribution, etc.) are mentioned
only briefly or not at all. In conjunction with the connection
between the activity of the adsorbent and the polarity of the
substances and the eluent, so very important in practice, one
would have liked to see - besides the eluotropic series @. 27)
- a reference to the ‘microcircular technique’ (E. Stahl) which
often allows one to determine from T L C the proper conditions for separation o n a column. The ninhydrin reaction
(p. 103) is not solely a means for the detection of cr-amino
acids.
In accordance with the subtitle ‘Introduction to the Critical
Performance of Chromatographic Procedures’ the possible
pitfalls are clearly indicated in each chapter, especially in the
Angew. Chem. internat. Edit. 1 Yol. 7 (1968) J No. 12
section on ‘Changes in Materials During Chromatography’.
The convincing critical assessment of Rf values is particularly
pleasing.
The reviewer finds the book very suitable as an introduction
to the field of chromatographic separation.
W. Barz [NB 752 IE]
Fortschritte der Arzneimittelforschung. (Progress in Drug
Research). Volume 10. Edited by E. Jucker. Birkhauser
Venag, Basel-Stuttgart 1966.1st Edit., 603 pp.. DM 128.-.
The introductory article, “Drug Research - Whence and
Whither”, to this new volumef21 has been written by R. G.
Denkewulter and M. Tishler. After a short historical introduction, the authors attempt to sketch out the position of
pharmaceutical research in the present day and in the future,
and to fathom and establhh the factors that could play an
important role. In so doing, they point to the uncertainty of
all predictions: “The true nature of a discovery is that it is
unexpected” (31 pages). - The article by G. Ehrhart “Considerations on the Development of Medicaments” deals with
a number of examples; the author refers to the fact that
“significant advances can only be made when new territory is
opened up by new fundamental discoveries” (13 pages). J. H. Beii and B. K. B. Lum give a 36-page review of “The pAndrenergic Blocking Agents, Pharmacology and StructureActivity Relationships”. After a critical discussion of the
receptor theory, relationships are considered between chemical constitution and exciting or blocking action, a number of
relevant compounds are listed, and their clinical pharmacology
is briefly touched upon (I 65 references).
111 Angew. Chem. 79, 911 (1967); Angew. Chem. internat. Edit.
6, 892 (1967).
[2] Cf. Angew. Chem. 79, 386 (1967); Angew. Chem. internat.
Edit. 6,892 (1967).
959
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