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N-(Pentafluoro-6-sulfanyl)iminosulfur tetrafluoride by reaction of thiazyl trifluoride with fluorine.

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Thus, 2 is formed only under kinetic control in liquid 1 at
temperatures slightly above - 78 "C. The yield of 2 (maximum 50% referred to reacted fluorine) is higher, the
smaller the ratio F2: 1.
We assume that 1 is oxidized by fluorine radicals via
short-lived intermediates to the radical SF?, which not
only reacts with F2 to give SF,, but also with the solvent 1
to give F5SNSFp. The latter stabilizes with formation of 2
and a fluorine radical, which continues the chain reaction:
SFF + NSF3
1
-
(F,SNSF.?}
-
FsSNSF4
+ FQ
(4)
2
2 is a stable, colorless liquid (b.p. 49"C, m. p. < - 100°C)
at room temperature, and can be heated to 60 C in metal
or Kel-F vessels, but decomposes in glass-particularly in
the presence of traces of moisture-to F,SNSOF2131.
The IR spectrum of 2 (gas) shows, aside from v(SN) at
1299 c m - ' (s), strong bands at 922 (vs), 841 (s), and 794
c m - ' (s), which can be assigned to the stretching vibrations of the SF5- and SF,-groups. The I9F-NMR spectrum
at 0 ° C is of AB4X4 type (SA=70.4, SB=78.1); the NSF,
group gives a broad singlet (S= 77.75)14].On lowering the
temperature, a further broadening occurs; at -70°C only
the AB, part for the SF,-group is observed ( ~ 5 ~ = 7 0 . 6 5 ,
SBa=77.96, JAB= 155.6 Hz).
The NSF, group in 2 can function both as fluoride donor and as fluoride acceptor:
O
N-(Pentafluoro-h6-suIfanyl)iminosuIfur Tetrafluoride
by Reaction of Thiazyl Trifluoride with Fluorine**
By AIfred Waterfeld and Rudiger Mews*
Reaction of NSF3 and fluorine at room temperature
yields SF, and N2:
NSF,
+ 3/2 FZ
+
SF,
2
+ 1/2 Nz
+ AsFS
S0:CW
F,SNSFFASF,O
-50-2lI-c
1
No products containing nitrogen-fluorine bonds are
formed, and therefore the reaction could be used for the
fluoro-calorimetric determination of the enthalpy of formation of 11'1.
We have now found that even under controlled, mild
reaction conditions no i21 products with N-F bonds are
formed, but instead the title compound 2, SF6, and N2:
2 + CsF
[*I
[**I
-
{NSFf}
-
SF,
+ 1/2N2
(3)
Prof. Dr. R. Mews, Dr. A. Waterfeld
Anorganisch-chemisches Institut der Universitat
Tammannstrasse 4, D-3400 Gattingen (Germany)
This work was supported by the Deutsche Forschungsgemeinschaft. We
thank Prof. Dr. G. V. R6schenthaler and Dr. M. Feigl, Universitat Bremen, for the NMR spectra.
3 54
0 Verlag Chemie GmbH. 6940 Weinheim. 1982
CS'[N(SF~)~]~
The salt like structure of 3 follows from the I9F-NMR
spectrum.
The IR spectroscopically characterized salt 4, whose anion contains two geminal pentafluoro-h6-sulfanyl groups,
opens u p an entry to bis(pentafluoro-h6-suIfanyl)amides[".
Received: December 7, 1981 [Z 78a IE]
German version: Angew. Chem. 94 (1982) 389
The complete manuscript of this communication appears in:
Angew. Chem. Suppl. 1982, 827-833
Reaction commences at about -78"C, recognized by a
slow drop in pressure (the number of molecules decreases).
A drastic change in the experimental conditions, e. g .
rapid heating or addition of BF3 or HgF2, leads to explosive-like reaction; SF, and N2 are formed.
Reaction (3) is strongly exothermic (-415.9 kJ/mol):
+ 1/2F2
W"'c
4
L
1
(5)
3, m.p. 103°C
[ I ] P. A. G. OHare, W. N. Hubbard, 0. Glemser, J. Wegener, J. Chem. Thermodyn. 2 ( 1970) 7 1 .
[2] a) In the presence of HF, however, reaction of 1 and F2 leads to
FSNFZ:
1
+ 2 HF
-
FSNH?
-
+
F5SNF2 2 HF
(A. Waterfeld, R. Mews, unpublished work).
[3] R. Hofer, 0. Glemser, Z. Nafurforsch. 8 3 0 (1975) 458.
141 In other iminosulfur tetrafluorides also, e.g, CH,NSF4, only an unresolved signal is found for the -NSF4 groups in the region of rapid exchange.
191 A. Waterfeld, H. Oberhammer, R. Mews, Angew. Chem. 94 (1982) 390;
Angew. Chem. I n t . Ed. Engl. 21 (1982) 355.
0570-0833/82/0505-0354 $ 02.50/0
Angew. Chem. I n ( . Ed. Engl. 21 (1982) No. 5
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reaction, thiazyl, iminosulfur, trifluoride, fluorine, pentafluoro, tetrafluorides, sulfanyl
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