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New Types of Polyenes with Cyclic Cross-Conjugated Bond Systems.

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The preparation of a tricyanatosilylamine could only be accomplished as shown below.
(K,Si)?NNa .+ (R?Si)ZNSiCI3 + (R3Si)ZNSi(NCO)3( b . p . 81 'Cjl mm)
Carbon monoxide is converted into sodium cyanide, disiloxane being eliminated.
CO
I
NaN(SiR:)z
-
In the course of studies on nine-membered rings containing
nitrogen and having 10 x-electrons 1,4,7-dibenzo[b,h]triazonines were obtained (with R. Bader).
[Max-Planck-lnstitut fur Kohlenforschung,
MiilheimjRuhr (Germany), January 8th, 19641 [I]
[VB 783/124 IE]
German version: Angew. Chem. 76, 276 (1964)
(CN)-Na+ -;- O(SiR3h
A five-membered SiN ring ( I ) can be built up.
New Types of Polyenes with Cyclic
Cross-Conjugated Bond Systems
R2Si-SiR2
CISiRZSiRzCl
~~
LiNRSiRzNRLi
4
2 LiC1 I-
Rh.
AR
Sik
(1)
H. Prinzbach, FreiburgjBreisgau (Germany)
Octamethyl- 1,2,4-trisila-3,5-diazacyclopentane
melts at I8 "C
and boils at 70 'C/I 3 mm.
[GDCh-Ortsverband Gottingen (Germany), November 25th,
1963. and Marburg (Germany) November 29th, 19631
[VB 777/119 IE]
~
In the dipolar structural formulae of the hydrocarbons sesquifulvalene ( I ) . calicene (2), and phenafulvalene ( S ) , the
central single bond joins, in each case, two relatively stable
organic ions.
German version: Angew. Cheni. 76. 234 (1964)
Investigations on Aromatic Systems
H . A . Stanb, Heidelberg (Germany)
Hexa-nt-phenylene (I), which has practically the same
geometrical arrangement in its inner ring system as [18]annulene and probably possesses a practically planar
structure, has like that compound x-electrons on all the
carbon atoms of its inner ring. However, in view of the metabonding of the phenylene groups, the cyclic x-conjugation
should be suppressed. Compound ( I ) was prepared (with F.
Binnip) from the Grignard compound of 3,3'-dibromodiphenyl with CoC12 in tetrahydrofuran. It can be distilled
&
'I1
I
i1)
without decomposition at 650L'C/10-4mmH g ; m.p. 509.5 to
511 "C. Its proton resonance (in view of its low solubility,
measurements have so far only been carried out in I-methylnaphthalene at 18OoC) gave no signals at 3.7-7.7 7 and
8.5-18.0 7 ; particularly strong shielding of the six inner
protons by an aromatic ring current can thus be excluded, as
anticipated. In the ultraviolet, ( I ) absorbs practically at the
Same wavelength (251.2 mp, E = 138000 in CHCI3) as biphenyl
(251.5 m p , E = 18300).
Attempts to prepare the benzocyclopropene (-3) (with J .
Ipoktschi) by photochemical elimination of nitrogen from
(2) did not lead to the desired product. Instead, the 9-phenylfluorene derivative ( 4 ) was obtained in very good yield.
Although ( I ) exists only in solution, it may be estimated
accurately by spectrophotometry and by its chemical reactions. On the other hand, doubly annellated derivatives of
( I ) , or those containing four phenyl groups on the fivemembered ring, are stable. Simple derivatives are obtained
by prototropic rearrangement of fulvenes ( 4 ) . In contrast
to the observation in the annellated series (4n), where only
a formal 1,5-hydrogen displacement to give (50) is found, a
competition reaction occurs in the analogous rearrangement
of (4b), and with increasing acceptor-character of R3,progressively more formation o f the vinyloguous heptafulvene (66)
takes place. The chemical behavior of this class of compounds including the smooth addition of acids and bases,
the site of the electrophilic attack, and adduct formation .- is
in agreement with the x-electron delocalization favored in
the transition state.
-
(u)
1 I,CC,I
5
5
3
is)
R'R2
R'
= -CdH?;
= R2 =
H:
R3 = -CN, -CI, -H, -OCH>
--N(CH3)z
R'-
[ I ] Also reportedJanuary iOth, 1964, at
Ortsverband Koln (Germany).
Aiigew. Chem. itttermtt. Edit.
1 Vol. 3 (1964)
No. 4
-CN. -CI,
--N(CH3)r
B
- H , -OCH?
meeting or the GDCh-
3 19
NMR-spectroscopic examination of ( 4 ) , (5), and ( 6 ) , and of
prototypes of (2) and (3) showed that the x-bonds are
largely localized in these cyclic cross-conjugated systems. On
the assumption of changes of bond lengths typical for olefins,
molecular-orbital calculations by Nnkajimn on ( I ) gave a
value for N-V’ excitation [*I, that is verified experimentally
(calculated: 3.20 eV; found: 3.16 eV).
[GDCh-Ortsverband Ruhr, Miilheim/Ruhr (Germany),
December 1 Ith, 19633
[VB 782/123 I€]
, 41
IT,
German version: Angew. Chem. 76, 2 3 5 (1964)
I 1c - sH - K
I1
C
-xH-KII-H
Transport Processes and Equilibria in the
Reduction of Oxides
H . J . Engell, Clausthal-Zellerfeld (Germany)
I n the reduction of metal oxides by gases, a dense layer of
the final reaction product can be formed. Then transport
processes in this layer can determine the rate of reduction.
In the reduction of wustite (FeO) to iron, an outer layer
of iron may be formed. The diffusion of oxygen in this
layer then determines the rate of reduction, as was shown by
comparison of the measured rate with the rate of diffusion of
oxygen in iron estimated by other methods. In the reduction of
magnetite (Fe304) to wustite (FeO), dense surface layers of
wustite are formed. In this case, however, the gas/oxide
phase-boundary reaction determines the rate of reaction, since
iron diffuses relatively quickly through the wustite layer.
During the reduction of oxide mixed crystals, the oxide phase
is decomposed. The extent of this decomposition depends on
the equilibrium conditions; its rate depends on transport
processes in the oxide, which are controlled by the disorder
equilibria. The form of metal precipitation observed here
is a result of these equilibria.
[GDCh-Ortsverband Nordwiirttemberg, Stuttgart (Germany)
January 16th, 19641
[VB 7851126 IE]
German version: Angew. Chem. 76, 307 (1964)
Mechanism of Osazone Formation and of the
Amadori Rearrangement
-
lI C =N - i% H - l<
1
c = X - N I I - 11
2 I1,X-YFI-R
I
+
NH, + R-NHz
K = C6H5
I
(7,
’6,
reducing enediamine [4] - hydrogenates further phenylhydrazine to ammonia and aniline. Aniline formed in this
manner accelerates the osazone formation in accordance with
the above equation.
[GDCh-Ortsverbarrd Unterfranken, Wiirzburg (Germany),
January 17th, 19641
[VB 787/129 I € ]
German version: Angew. Chem. 76, 307 (1964)
Complex Formation with Polymolybdate Ions
K . F. Jrrhr, Berlin (Germany)
Telluromolybdates can be detected by conductometric,
potentiometric, spectrophotometric, and salt-cryoscopic titrations of acidified NazMoO4 solutions (1.0-1.6 H+/MoO;-)
with solutions of Te(OHj6. With increasing concentrations of
Te(0H)Gin solutions with 1.0-1.14 H+/MOO~-,telluro-1: 12-,
telluro-I : 7-, and telluro-1 : 6-molybdates are formed successively; at 1.33 HL/MoO:-, the 1 :7 and then the 1 : 6
complex are formed. On titrating the molybdate with
solutions of AIJ- salts, an alumino-l:7- and then an alumino1 :6-molybdate result; here a I : 12 complex cannot be detected.
The telluro-I : 6 complex is the familiar heteropolyanion
TeMo60&, which consists of a flat ring of six Moo6 octahedra with Te6+ at the center. The new 1 : 7 complex is
thought to be an adduct of H4TeOg- and the “paramolybdate
ion” M070:~-, while the new 1 : 12 complex is a l-tellurium-2hexamolybdate ion with Te6 as an octahedrally coordinated
central ion sandwiched between two superjacent Mo6024
rings. The I -tellurium- I-hexamolybdate was shown by saltcryoscopic measurements to be the most stable complex at
two H’/MoO;- ratios (1.14 and 1.5Oj, since it can be formed
from two different hexamolybdate ions which predominate
at these ratios. Conductometric titration of an acidic molybdate solution ( 1 . 5 H‘/MoO:-) with free HJPOJ led to a
phospho-1 : I?-molybdate with consumption of H+. This
complex condenses to form the well known l-phosphorus-2dodecamolybdate jon only in strongly acidic solution and js
thought to be an inclusion compound with a phosphate ion
inside a hollow spherical dodecamolybdate ion, which in
such acid solutions is in equilibrium with a hexamolybdate
ion. The fact that the dodecamolybdate ion has a hollow
interior suitable for the formation of inclusion compounds is
demonstrated by the formation of a 1-(methyl redj-l-dodecamolybdate ion, which was detected by conductometry and
spectrophotonietry. On adding methyl red to a molybdate
solution with 1.5 H2./MoO;-, the initially red solution
gradually turns yellow as the indicator is converted into the
anion by inclusion inside the hollow space within the dodecamolybdate ion. Even large additions of sulfuric acid do not
restore the red color of the solution; however, phosphoric
acid, displaces the indicator from the cavities to form the
more strongly complexed 1 -phosphorus-dodecamolybdate
ion and colors the solution red with the liberated indicator.
When ammonia is added dropwise to the yellow solution of
~
F. Micheel, Miinster/Westfalen (Germany)
The osazone reaction discovered by Emil Fisclier in 1884 is
not initiated by an Amadori rearrangement of an aldose
phenylhydrazone; instead, some phenylhydrazine first decomposes in the acidic solution by partial disproportionation
into aniline, ammonia, benzene, nitrogen, etc. The phenythydrazone ( I ) reacts with the aniline produced in this
manner by transamination to form a 1 -phenylamino derivative (2) which is readily converted by further aniline
and H+-ions into a 1-deoxy-I-phenylaniinoltetosederivative
( 4 ) [I]. The Amadori rearrangement proceeds very rapidly
in the presence of excess amine; this also shows that the
intermediate product is not a Schiff’s base but a 1,l-bis-Nacetal (3) [2].
Compound ( 4 ) reacts rapidly with phenylhydrazine to give a
I-deoxy-1-phenylaminoketosephenylhydrazone (5), which
in turn can react rapidly with excess phenylhydrazine to form
the osazone (7). By using 14C-phenylhydrazine it can be
demonstrated [3] that this step does not involve an intramolecular redox reaction but that (5) or ( 6 ) -- as a strongly
[*I
N-V’ excitation is detined as the transition between the highest
MO and the lowest excited ringlet state.
[ l ] F. Micheel a n d 1. Dijotzg, Liebigs A n n . Chem. 669 136
(1963).
121 F. Miclreel and I. Diiortg, Liebigs Ann. Chem. 658, 120
(1962).
[3] F. Micherl and I. Diiong, unpublished rcsults.
320
[4] F. Miclreel, G. Bode, a n d R . Wirbert. Rcr. dtsch. chem. Ges.
70, 1862 (1937).
Arigew. Clietii. iitteriint. Edit./ Vul. 3 (1964) 1 Nu. 4
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