close

Вход

Забыли?

вход по аккаунту

?

Dithieno[3 4-b 3 4-e]-[1 4]-dithiine.

код для вставкиСкачать
anes [51. As a result the intramolecular Cl.. .C1 contacts are
increased to values ranging from 3.308 to 3.338 A, and the
planes of the four chlorines above, and the four chlorines
below the central ring are separated by 2.454 A.
The bond distances give n o evidence for conjugation. The
distances in the ring are normal for single bonds between spz
hybridized carbons, and the C = C and C-CI bonds compare
closely to their respective values (1.324 and 1.710 A) in 1,ldichloroethylene [GI.
Received: April 29, 1969
IZ 13 IE]
n
German version: Angew. Chem. 81, 567 (1969)
[*I Dr. F. P. van Remoortere and Dr. F. P. Boer
The Dow Chemical Company
Eastern Research Laboratory
Wayland, Mass. 01 778 (USA)
[I] B. Heinrich and A. Roedig, Angew. Chem. 80, 367 (1968);
Angew. Chem. internat. Edit. 7, 375 (1968).
[21 E. Heilbronner, Theoret. chim. Acta 4 , 64 (1966).
[31 We are grateful to Prof. Dr. A. Roedig for supplying the
crystals.
[4] D . Sayre, Acta crystallogr. 5, 60 (1952).
[51 B. Greenberg and 8. Post, Acta crystallogr. E 24, 918 (1968).
[6] R . L . Livingstone, C. N . R. Rao, L . M . Kaplan, and L . Rocks,
J. Amer. chem. SOC.80, 5368 (1958).
The Bis(chlorosu1fur)nitrogen Cation
in [NS2CI2]+[BCl4]By 0. Glemser, B. Krebs, J. Wegener, and E. Kindlerc*]
If boron trifluoride ( p = 450 torr) is allowed to react with sulfur nitride trifluoride ( p = 300 torr) for a few days in a 2-1
glass flask, 3 4 g of a yellow crystalline substance is formed
which has the composition BNSzC16 and which proved to be
the ionic compound [NS2C12]+[BC14]-.
Fig. 1. Bond lengths (A) and bond angles ( " ) (a) in the [NSzC12]+ion
and (b) in the [BCIII- ion.
The experimentally determined dimensions are in good
agreement with such a type of bonding: a previously derived
empirical relationrll gave a bond order of about 1.7-1.8 for
the observed N-S bond length; the S-CI bond length corresponds to that of an ideal single bond. The WS2C12]+ ion
is, within the limits of error, planar and has cis configuration
with approximate CzVsymmetry. On the basis of the electron
pair repulsion model, the bond angles are plausible if one
assumes a n approximately equal participation of the resonance structures (2) and (31. The structure of the remarkably
stable tetrahedral [BCLJ- ion in compound ( I ) has not as
yet been investigated; in this compound there is virtually no
distortion of the tetrahedron, the bond angles varying between 109.0 and 109.9 O.
Received: May 14, 1969
[ Z 16 IE]
German version: Angew. Chem. 8J. 568 (1969)
[*I Prof. Dr.
0. Glemser, Doz. Dr. B. Krebs, Dip1.-Chem. J.
Wegener, and E. Kindler
Anorganisch-Chemisches Institut der Universitat
34 Gottingen, Hospitalstr. 8-9 (Germany)
[l] 0 . Glemser, A. Miiller, D . Bohler, and B. Krebs, Z . anorg.
allg. Chem. 357, 184 (1968).
Dithieno[3,4-6,3',4'-e]- [1,4]-dithiine
The gaseous products of this reaction are Nz, Clz, BF3, and
BF2CI. The new compound is also formed in the reaction of
trithiazyl chloride, N3S3C13, with Clz and BC13 or SClz and
BC13.
Bis(chlorosu1fur)nitrogen
tetrachloroborate,
[NSzC13]+[BCl4]- ( I ) is very hygroscopic and rapidly decomposes with
incomplete evolution of BCI3; the stoichiometric amounts of
Nz. SzC12. SC12, and BC13 corresponding to the empirical
formula are liberated o n heating in a bomb tube at S O T .
O
d
: = 1.98 g/cm3. Mass spectrum (rel. intensities): SN+ (loo),
SCl' (79), BC12+ (33), NSCl+ (33), Clt (33), S+ (25), SC12+(10),
BC13+ (3). Infrared spectrum (cm-1): 1380 (s), 1340 (s). 1325
(s), 1265 (m), 705 (w). 525 (s), 423 (s), 408 (s). Raman spectrum (cm-1): 720 (s), 706 (w). 652 (w), 516 (s), 499 (m), 452
(s), 408 (m),200 (s), 132 (s). 83 (s), 38 (m), 21 (m). The molecular weight was determined cryoscopically in benzene as
156.6 (calc. 301.7). thus indicating dissociation of the compound into two parts.
Compound ( I ) crystallizes monoclinically in the space group
C&, P21/C with a = 6.441 f 0.005, b = 16.008 f 0.010, c =
y =
9.864& 0.007A, p = 103.30rt 0.05". Z = 4 ; d ~ - ~ ~2.024
gm/cm3. The composition and structure of the compound
was determined by X-ray structural analysis. The structure
could be determined directly by iterative use of the Sayre
equation. For this purpose about 1800 independent reflections were determined on a single crystal diffractometer
(MoK,radiation, scintillation counter). After refinement by
the method of least squares, a discrepancy factor R = 5.9%
was obtained. The structures and structural parameters of
the cation and anion are as shown in Figures l a and l b . Two
doubly degenerate resonance structures are possible for the
[NS2C12]+ ion.
598
By M. J . Janssen and J. Bos[*l
Waronkow and Pereferkowitsch
have recently reported o n
the preparation of dithieno[2,3-b,3',2'-e]-[1,4]-dithiine. We
have now prepared the inomeric compound dithieno[3,44,3',4'-e]-[1,4]-dithiine ( I ) [21 by heating 3-bromo-4-thiophenethiol (15.6 g, 0.08 mole) [31 with 4.5 g KOH (0.08 mole) and
5.7 g CuzO (0.04 mole) in 300 ml dimethylformamide for
20 h at 130 OC (yield 3.7 g = 40%, after recrystallization
from cyclohexane m.p. 145-146 "C). NMR: S = 7.40 ppm
(s); UV: Amax (ethanol) = 270 nm (E = 9100).
f:
(1)
Q
(2)
Oxidation of ( I ) with one equivalent of hydrogen peroxide
in methylene chloride/acetic acid (2:l) (6 days at room temperature) affords the 4-monoxide (yield 66 %, after recrystallization from CHC13/CC14 m.p. 183.5-184 "C). The N M R
spectrum shows two doublets at 6 = 8.04 and 7.36 ppm (J =
3 Hz). This spectrum is consistent with the given structure
only, since the coupling constant of 3 Hz is characteristic of
(ethanol) =
2,Shydrogen atoms in thiophener41. UV: A,,
244 nm (c = 15400). The 4,8-dioxide (2) is formed when ( I )
is boiled under reflux for 24 h with two equivalents (or the
4-oxide with one equivalent) of Hz02 in acetic acid/methylene
chloride. The yield of (2), after recrystallization from acetic
acid, amounts to 40% [from ( I ) ] ; m.p. 230 OC, Amax (ethanol)
= 250 nm (shoulder) (c = ca. 8600).
Angew. Chem. internat. Edit.
Vol. 8 (1969) 1 No. 8
The NMR-spectrum of (2) (in [D6]-DMSO) shows two sharp
signals of unequal height at 8 = 8.50 and 8.60 ppm. At 120 "C
the signals broaden, at 180 "C there is only one sharp absorption (8 = 8.55). Compound (2) obviousIy gives rise to two
isomers in which the SO groups are either cis or trans 151 and
which are interconverted rapidly at higher temperatures. The
original signals are observed in the same intensity ratio when
the solution is cooled. Prolonged heating at 200 "C does not
alter the ratio of the components.
can be shifted at lower temperatures largely towards the
complex. In T H F solution the simple SiCH3 proton resonance signal splits at -85 "C into two lines of equal intensity,
and the signals for bipy correspond to bipy bound as complex [cf. (CzH5)zNi . bipy 1311.
These results accord with the proposed structure ( l a ) , in
agreement with binding of the bipy to only one Si atom of a
molecular adduct (non-equivalence of the two Si-methyl
groups!).
Received: May 27, 1969
[Z 19 IEI
German version: Angew. Chem. 81, 570 (1969)
Cl, ,CH3
Cl,
["I Prof. Dr. M. J. Janssen and J. Bos
Institut fur Organische Chemie der Universitat
Bloemsingel 10, Groningen (Netherlands)
111 M . G. Woronkow and A . N . Pereferkowitsch, Angew. Chem.
81, 257 (1969); Angew. Chem. internat. Edit. 8, 272 (1969).
[2] For the tetraacetyl derivative of ( I ) , see 0.Scherer and F.
Kluge, Chem. Ber. 99, 1973 (1966).
131 S. Gronowitz, P . Moses, and A. B. Hornfeldt, Ark. Kemi 17,
237 (1961).
[4] R. A. HoHman and S . Gronowitz, Ark. Kemi 16, 515 (1960).
151 This is also the case with S,10-thianthrenedioxide; see K . F.
Pureell and J. R. Berschied, J . Arner. chem. SOC. 89, 1579 (1967).
2,Y-Bipyridine Adducts of Disilanes
By D . Kurnrner, H. Klister, and M . Speck[*]
During studies of the chemistry of polysilanes we succeeded
in the first synthesis of amine complexes of disilanes, namely,
tetrachlorodimethyldisilane-bipyridine ( I ) and hexachlorodisilane-bipyridine (2). Previous attempts to isolate such
substances failed because of base-catalyzed rearrangement
of the disilanes[1.21. Compounds ( I ) and (2) provide examples of a class of compound that is important for, inter
alia, the study of the nature of donor-acceptor complexes and
of the rearrangements of di- and poly-silanes.
The 1:l bipyridine (= bipy) addition compound of ( I ) is
formed smoothly from the components in apolar organic
solvents at room temperature, separating as a lemon-yellow
crystalline powder.
Pentane
CIzCH3SiSiCH3C12+ x bipy
4
ClzCH3SiSiCH3CIz . bipy + (x-1) bipy
~
(1)
Analysis and 1H-NMR spectra confirm the 1:l composition;
it was not possible to obtain an addition compound containing more bipyridine (e.g., 1:2) even when using a large excess
of bipy.
The complex ( I ) dissolves easily in benzene and tetrahydrofuran with a pale yellow color, but according to the cryoscopically determined molecular weight (found, 177 in
benzene) and the NMR spectra it is widely dissociated
therein into the starting materials (see Table). The UV spectrum of the colorless T H F solution (10-3 mole/l) shows only
the two unchanged bands of bipy (235, 281 nm); in the solid
state spectrum (Nujol suspension) there appears also a broad,
weaker absorption band without a definite maximum,
stretching to 600 nm. The yellow color is ascribed to chargetransfer transitions. Measurements of conductivity of ( I ) in
acetonitrile at 25 "C show no change from that of the pure
soivent.
Compound ( I ) sublimes in a vacuum at 4O-5O0C, being
thereby completely dissociated also in the vapor state, according to the mass spectrum. The dissociation equilibrium
in solution:
4
1
No further indication can yet be given about the arrangement
of the bipy in this structure (cis-cis or cis-trans to the neighboring Si atom). A single-crystal X-ray structure determination is in progress 141. Although the solid compound remains
unchanged for months at room temperature, solutions of ( I )
in T H F or dioxane are not stable at 25OC; they change
within a few weeks to deep reddish-brown solutions from
which a new bipyridine-silicon complex can be isolated; this
is amorphous (X-rays) and, according to IH-NMR studies, is
of stoichiometric composition. This intermediate also decomposes above 150 "C giving CH3SiC13 and unidentified
higher methylchlorosilicon compounds. Chlorosilane catalyzes the solution reaction.
Like (C12CH3Si)z. SizCI6 reacts with bipy in pentane giving
exclusively the yellowish-white 1:1 adduct (21,whose existence is secured by analyses, X-ray powder diagrams (individual diagram, no bipy, Sic14 . bipy, bipy . HCl). and thermal
sensitivity (formation of a dark green color above 80°C).
In tetrahydrofuran another reaction takes place at 25 "C,
formation of a dark green color and decomposition occurring
within a few minutes; but the solid complex (2) is completely
stable at 25 "C.
1H-NMR data (v in Hz at 60MHz; TMS = 0 Hz) of (I) and
its components (ca. 10% in THF).
32
32
32
-85
-85
-85
-
61.0
-
509.3
60.0
508.2
65.2
-
-
530.5
50.5; 47.5
552.5
Tetrachlorodirnethylne-2,2'-bipyridine (1)
(ClzCH3Si)2 (3.19 g, 15.0 m o l e s ) is condensed under
reduced pressure onto bipy (2.87 g, 18.4mmoles) in pure
pentane. The mixture is allowed to warm slowly to room
temperature with stirring. A yellow precipitate is formed
which two hours later is filtered off in absence of air and
washed several times with dry pentane. Recrystallization
from acetonitrile affords ( I ) as large, yellow, transparent
crystals, m.p. 102 "C (decomp.) (3.7 g, 70 %). If there is even
a slight excess of the chlorosilane component, the precipitate,
which is yellow at first, becomes dark green within an hour,
giving, inter alia, CH3SiCl3.
Hexachlorodisilane-2.2'-bipyridine ( 2 )
The preparation is analogous to that above, with condensation of less than an equivalent amount of (C13Si)Z onto a
bipy solution in pentane. The yield is almost quantitative.
It was not possible to find a solvent for the complex. Decomp.
pt. 108 "C (green color).
X-ray powder diagram (Cu-IQ: 5.9 vs. 6.6 vs, 7.6 vw, 8.8 m,
9.65 vw. 10.6 w. 11.75 vs, 13.4 m, 14.25 m, 14.75 m, 15.85 s.
Angew. Chem. internat. Edit. 1 Vol. 8 (1969)
No. 8
599
Документ
Категория
Без категории
Просмотров
1
Размер файла
255 Кб
Теги
dithieno, dithiin
1/--страниц
Пожаловаться на содержимое документа