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An External Magnetocatalytic Effect.

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quantitatively separated by gas chromatography on a Ucon
LB 550 X Golay column (200 m ; internal diameter 0.5 mm).
A capillary chromatograph with a flame-ionization detector
was used. The carrier gas was helium (4.5 ml/min), and the
temperatures used are shown in Table 1 .
Table 1. Temperatures of flash heater, column, and detector.
Isomers
Chloro-n-heptanes
Bromo-n-heptanes
Chloro-n-octanes
Bromo-n-octanes
Chloro-n-decanes
5-Aralkyl derivatives of (3) have been obtained in almost
quantitative yields by catalytic hydrogenation (10
Pdcharcoal; dioxane; room temperature; 10 h) of the yellow
5-arylidene derivatives ( 4 ) which are readily available by the
condensation of aldehydes with the active methylene group of
(3), R = H. The following compounds were prepared:
m. p.
m.p.
m.p.
m. p.
m.p.
m.p.
m.p.
m.p.
170 "C
170-175 "C
175--179°C
230 ' C
232 OC
70 "C
90 ' C
90 "C
90 "C
I20 "C
The retention times of the isomeric halogenated hydrocarbons
and the resolution obtained for each individual pair of isomers are set out in Table 2.
The quantitative evaluation of the chromatograms was confirmed by the analysis of test mixtures. The maximum relative
error found was about 5 %, so that the use of correction factors is unnecessary.
The gas-chromatographic analysis of the unstable bromo-ndecanes still presents difficulties.
176 "C
ca. 290 "C (decomp.)
183 " C
230 "C
197 "C
181 "C
ca. 290 " C (decomp.)
= 116°C
Table 2.
70 "C
90 "C
90 "C
90 "C
120 "C
Retention times (tr) and effective resolution (8)[*I for the isomeric halogenated
Bromo-nheptanes
tr
8
[mini
['%I
135
94
91.5
85
100
98.7
Bromo-noctanes
Chloro-noctanes
Chloro-ndecanes
tr
[minl
8
100
100
100
151
114
-
103
101
100
94.4
100
94.4
tr
[minl
8
tr
8
[%I
[mini
[%I
168
113
110
102
100
98.9
100
170
119
115
-
105
-
[";I
~~
I-X-R
2-X-R
3-X-R
4-X-R
5-X-R
164
114
100
96.1
110
103
-
100
-
Compounds (3), R = H or alkyl, have anti-inflammatory
activity. They are stable towards hydrazine and amines,
whereas alkali hydroxide cleaves the ring and liberates hydrazobenzene. Also, the attempted alkylation of f 3 ) with alkyl
halide and NaOH resulted in the formation of hydrazobenzene.
100
-
-
-
110
Received, September 7th, 1964
[Z 827/657 IE]
German version: Angew. Chem. 76, 890 (1964)
-
[ I ] Li-Hoan Kung, Ph. D. Thesis, Technische Hochschule Aachen
1964.
[2] H. Kaiser: Chromatographie in der Gasphase. Bibliographisches Institut, Mannheim 1960, Vol. 11, p. 32.
Received, September 9th, 1964 [Z 822/652 IE]
German version: Angew. Chem. 76, 920 (1964)
[ l ] Sr. Goldschrnidt, Liebigs Ann. Chem. 437, 213 (1924).
[2] While this work was in progress, a patent has appeared,
describing the synthesis of (3), R=H, from sulfoacetic acid dichloride and hydrazobenzene without reporting the yield: R .
Doson and V. Papesch, U.S.-Patent 3037027; Chem. Abstr. 57,
12502 (1962).
[3] A . Michaelis and F. Schmidt, Liebigs Ann. Chem. 252, 308
(1889).
Gas-Chromatographic Separation and Analysis of
Isomeric Halogenated Hydrocarbons
By Dr. Elisabeth Bendel, cand. phys. W. Meltzow, and
Dr. Li-Hoan Kung
Institut fur Technische Chemie der Technischen Hochschule
Aachen (Germany)
After chlorination or bromination of high-molecular, straightchain hydrocarbons with, for example, N-chloro- or Nbromosuccinimide, t-butyl hypochlorite or hypobromite [ I ]
the isomeric chlorides of n-heptane, n-octane, n-decane and
the isomeric bromides of n-heptane and n-octane were
750
An External Magnetocatalytic Effect
By Doz. Dr. W. Haberditzl and Dipl.-Chem. Klaus Muller
Physikalisch-Chemisches Institut der Humboldt-Universitit
Berlin (Germany)
The existence of external magnetocatalytic effects, i. e. alterations of catalytic activity within external magnetic fields, has
been the subject of much controversy. We have now detected
such an effect with the enzyme glutamic dehydrogenase
(GI DH).
GIDH catalyses the reaction:
a-Oxoglutarate
+
NH,
+
DPNH
+
Glutamate
+ DPN +
H2O
The changes in the concentration of DPNH with time were
followed by spectrophotometry [l], and the catalytic activity
was calculated in units per ml [2]. The reaction mixture comprised 3 mi of 0.05 M triethanolamine buffer (pH 8.0),
0.045 ml of 0.01 M DPNH, 0.03 ml of 0.26 M EDTA, 0.1 ml
of 3 M ammonium acetate, and 0.03 ml of 10-7 M GIDH.
After addition oF0.06 ml o f 0.4 M sodium E-oxoglutarate, the
extinction of the solution at 366 m p was measured at one-
Angew. Chem. internat. Edit. I Vol. 3 (1964)
NO. I 1
minute intervals. After 5 min, the sample cell (light path 1 cm)
was placed between the poles of an electromagnet in an inhomogeneous field (distance from poles 13.5 mm, magnetic
field strength 15000 Gauss) for 40-50 min. The extinction
was thereafter again measured at one-minute intervals for
5 min. A duplicate determination was carried out on a cuvette
not placed within the magnetic field. There was generally a
difference in temperature of 0.1 to 0.3 "C between the solutions within and ouside the magnetic field. The temperature
dependence of the enzymatic activity was 1.5 units/'C at
25 "C and 1.8 units/"C at 27°C.
In four replicate experiments, the activity of the GlDH inside
the magnetic field was 12-15
(in one series of experiments
7 'I;) less than that outside t i e magnetic field.
distillation. It ignites spontaneously on filter paper in contact
with air.
[Z 831/653 IEI
Received, September 3rd, 1964
German version: Angew. Chem. 76, 891 (1964)
Preparation of Malonic Acid by Carboxylation of
Acetic Acid
[ I ] E. Schniidt in H . U. Eergrneyer: Methods of Enzymatic
Analysis. Verlag Chemie, Weinheim/BergstraBe, and Academic
Press, New York, 1963, p. 752.
[2] 7'. Eurher, 2. Naturforsch. 86, 5 5 5 (1953). One unit is the
amount of enzyme dissolved in 1 ml which alters the extinction
at 366 mp (light path: 1 cm) by 0.100 within 100 sec at 25 'C.
Synthesis of Octabenzylcyclotetrastannane
By Priv.-Doz. Dr. W. P. Neumann and Dipl.-Chem. K. Konig
lnstitut fur Organische Chemie
der Universitat GieBen (Germany)
Received, September 14th, 1964 (Z 823/643 IE]
German version: Angew. Chem. 76, 892 (1964)
[ l ] W. P . Neumann, Angew. Chem. 74,122 (1962); Angew. Chem.
internat. Edit. 1, 165 (1962); W. P . Neumann and J. Pedain, Liebigs Ann. Chem. 672, 34 (1964).
[2] W. P . Neumann and K. Konig, Angew. Chem. 74, 215 (1962);
Angew. Chem. internat. Edit. 1 , 212 (1962); Liebigs Ann. Chem.
(1964), in the press.
[ 3 ] W. V. Farrar and H. A . Skinner, J. organomet. Chem. I , 434
(1 964).
By Dr. B. Raecke
Forschungslaboratorium der Firma Henkel & Cie. GmbH.,
Dusseldorf (Germany)
The decarboxylation of malonic acid may be regarded as an
equilibrium reaction. Salts of malonic acid can be produced
from acetates and carbon dioxide if the hydrogen ions
liberated during the reaction are removed [I].
The carboxylation proceeds especially smoothly with
potassium acetate, which in the presence of potassium carbonate reacts with C02 under pressure and above 200 "C to
give potassium malonate:
CH3COOK
Catalytic condensation of dialkyltin dihydrides and diaryltin
dihydrides gives rise to crystalline aliphatic [ I ] and aromatic
[2] cyclostannanes containing five-, six-, or nine-membered
rings. We have now succeeded in preparing an analogous
compound with a four-membered ring, viz. octabenzylcyclotetrastannane. It is formed from dibenzyltin dihydride in
almost quantitative yield at 50 "C in dimethylformamide,
which also acts as catalyst, and a trace of dibenzyltin dichloride as co-catalyst; the product is very sensitive to air but
crystallizes from toluene/ligroin as beautiful pale yellow
prisms (m.p. 226-228 "C with partial decomposition). It is
highly soluble in hot benzene but sparingly soluble in cold
benzene. On degradation with iodine in benzene, it affords a
quantitative yield of pure dibenzyltin diiodide. This reaction,
together with its molecular weight (determined by osniometry), analyses, and spectra substantiate its structure.
+ COz + K2CO3 +
KOOC-CH2-COOK
+ KHCO3
Suitable catalysts include finely powdered metals and metal
oxides, especially iron and FezO3.
When anhydrous potassium acetate (30 g) is heated with
anhydrous potassium carbonate (120 g) and iron powder
(1 g) in an autoclave at 3OO0C for 3 h at ca. 500 atm Con,
can be isolated from the
pure malonic acid (ca. 24 g; 75.2
reaction mixture.
Other carboxylic acids with hydrogen atoms in the a-position
can also be carboxylated in this way, although the yields are
considerably lower.
x)
Received, September loth, 1964 [Z 820/641 IE]
German version: Angew. Chern. 76, 892 (1964)
~~
[ I ] German Patent Application H 49,852 IVb/l20. Henkel & Cie.
GmbH.
A Simple Synthesis of Organic
Di- and Polystannanes
By Priv.-Doz. Dr. W. P. Neumann and
Dip1.-Chem. B. Schneider
Institut fur Organische Chemie
der Universitat GieBen (Germany)
t 4 H2
When the condensation was carried out in pyridine, a
crystalline mixture containing higher cyclic homologues was
obtained; these probably included the five- and six-membered
ring compounds. The ring size in the products formed
depends not only on the cataIyst used, but also on the nature
of the organic substituent on the tin (cf. [1,2]). Recently, the
analogous octa-t-butyl compound was prepared by a different
route as the first example of a cyclotetrastannane [3].
Organotin hydrides [ I ] can be condensed with organotin
oxides, giving rise with surprising ease and occasionally even
in an exothermic reaction either to symmetrical and unsymmetrical hexaalkyldistannanes [Equation (a)], or to the
octaalkyltristannanes [Equation (b)] hitherto obtainable
only with difficulty, or to polystannanes [Equation (c)].
Aryltin compounds react faster than the corresponding
alkyltin compounds. When R = iso-C4H9, reaction (c, leads
to a polydiisobutyltin polymer which still contains some
Sn-0-Sn groups [2].
Our starting material, dibenzyltin dihydride, was hitherto
unknown and was prepared from pure dibenzyltin dichloride
using lithium aluminohydride in ether at 0°C ( " s ~ H at 1843
cm I , broad absorption); it was used without previous
Angew. Chem. internat. Edit. / Yo[. 3 (1964) I No. I1
75 1
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