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An Explosion during the Oxidation of Tetralin with Hydrogen Peroxide in Acetone.

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markable similarity of the infrared and ultraviolet spectra of
these complexes with those of bisdithiobenzilnicke1.
Received, July 13th, 1964
[Z 783/607 IE]
German version: Angew. Chem. 76, 715 (1964)
[ I ] G . N. Schrauzer and V . Muyweg, Z . Naturforsch. 196, 192
(1964).
[2] G. N . Schrauzer, V. Muyweg, H . W . Finck, U . Miiller- WesterhoK and W . Heinrich, Angew. Chem. 76, 345 (1964); Angew.
Chem. internat. Edit. 3, 381 (1964).
[3] R . B. King, Inorg. Chem. 2, 326 (1963).
Since the starch-iodide test for free HzOz had been negative,
we suspect the formation of acetone peroxides as the cause
of the explosion. Other routes to a-tetralone are available[2].
Received, July 13th, 1964
[Z 785/621 IE]
German.version: Angew. Chem. 76, 716 (1964)
[ I ] W.Treibs, G. Frunke, G. Leichsenring, and H . Roder, Chem.
Ber. 86, 616 (1953).
[2] E. L. Martin and L. F. Fieser in: Organic Syntheses. Wiley,
New York 1943, Coll. Vol. 11, p. 569; R. B. Wagner and H . D .
Zook in: Synthetic Organic Chemistry, Ketones. Wiley, New
York 1953, p. 316 et seq.
Condensation of Active Methylene Compounds
with Isothioamide Groups
Radiochemical Hydroxylation of Phenolic
Compounds
By Dr. K. Hartke [*]
By Dr. F. Merger and Dip1.-Chem. D. Grasslin
Instituto Central de Quimica, Universidad Concepci6n (Chile)
Enol ethers with activating groups (-CN, -COzR, >C=O)
in the F-position react with amines to form amino olefins (3).
The latter are also readily obtained by condensation o f
compounds containing active methylene groups (1) with
compounds (2) containing the group -N=C-SR
(isothioamides, isothioureas, or iminothiocarboxylic esters). The
condensation takes place without a catalyst by mixing the
components in a solvent, e.g. alcohol or ether. With compounds containing particularly reactive methylene groups,
e . g . malonitrile or dimeric malonitrile, the reaction is frequently exothermic. In other cases the reaction mixture is
allowed to stand for several hours to days at room temperature or is heated for some time on a water bath. Some
compounds obtained in this way are given in the Table
(structures determined by elementary analyses and infrared
spectra; independent synthesis of (3e) [l]).
x\
/CH2
+ R
- 'SR3
x, P'
+ HSR3
Y
Organisches-Chemisches Institut
der Universitat Heidelberg (Germany)
We have found that gallic acid and other phenolic carboxylic
acids are hydroxylated at room temperature in water by the
action o f 6OCo y-rays. The hydroxylation, which can be
carried out on a preparative scale, occurs with remarkable
selectivity ortho to existing hydroxyl groups and proceeds
more rapidly in the presence of oxygen than when oxygen is
excluded. nz-Dihydroxybenzoic acids are particularly easily
hydroxylated between the two hydroxyl groups.
Irradiation of a 1 % aqueous solution of gallic acid saturated
with oxygen (dosage rate of the 6OCo y-ray source: 4 . 0 6 ~105
r/h; irradiation time: 300 h) gave 2,3,4,5-tetrahydroxybenzoic acid in 52.8 % yield with a G-value [*] of 0.22;
separation of the residual gallic acid was achieved by fractional cr) stallization and preparative chromatography. The
G-values for some other phenolic carboxylic acids are considerably higher.
Nitrophenols are hydroxylated much faster than phenolic
carboxylic acids. p-Nitrophenol affords 4-nitrocatechol, and
4- or 5-nitropyrogallol give the hitherto unknown 1,2,3,4tetrahydroxynitrobenzene (G = 1.4 1).
Received, July 20th. 1964
[Z 789/619 IEI
German version: Angew. Chem. 76, 752 (1964)
Iy
X
-CN
-CN
-COCH3
-CN
-CN
-CN
-C02CzH5
-CO-CH,
-C N
-CN
[*I The G-value indicates the number of molecules formed
per 100 eV.
-CH3
--H
-H
-N(CH3)2
--SCH3
Benzyl
Cyclohexyl
Cyclohexyl
-CH3
-CH3
114-115
116- 117
87-88
165-166
120-121
86
62
57
83
85
t-Butylaluminum Compounds
By Dr. H. Lehmkuhl
Max-Planck-Institut fur Kohlenforschung,
Miilheim/Ruhr (Germany)
[*I Present address: Institut fur Pharmazeutische Chemie und
Lebensmittelchemie der Universitat Marburg/Lahn (Germany).
[I] Cf. R . Gompper and W. T6pJ7, Chem. Ber. 95, 2871 (1962).
The addition of al-H onto olefins occurs predominantly
according to Markownikoffs rule [ l , 21; the reaction of al-H
with isobutene thus gives triisobutylaluminum ( I ) , but no
tri-t-butylaluminum (2).
/
al-H
An Explosion during the Oxidation of Tetralin
with Hydrogen Peroxide in Acetone
By Dr. H. Seidl
Institut fur Organische Chemie
der Universitat Munchen (Germany)
During the preparation of a-tetralone, tetralin was oxidized
with 30 % H202 according t o the method of Treibs et al. [I].
On subsequent evaporation of the reaction mixture in vucuo,
as the last of the solvent distilled over, the distillation residue
exploded with great violence, causing injuries and damage.
640
+
HZC=C(CHJz
al-CH2-CH(CH3)2
(I)
al-C(CH3)s
(2)
It was expected [2] that (2) would be unstable and would
rearrange to ( I ) via al-H and isobutene. Isomerization t o
the primary trialkylaluminum occurs with triisopropylaluminum [3]. We found, however, that (3), the etherate of
(2), which is produced in 75 % yield by the reaction in ether
of t-butylmagnesium chloride with AlCI3 in a molar ratio of
3: 1, is actually quite stable.
13)
[
H3C -
!?+A
1 . (C 2H5),O
Angew. Chem. internut. Edit. 1 Vol. 3 (1964) 1 No. 9
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hydrogen, explosion, oxidation, peroxide, tetralin, acetone
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