ISSN 1070-3632, Russian Journal of General Chemistry, 2006, Vol. 76, No. 3, p. 497.
Pleiades Publishing, Inc., 2006.
Original Russian Text
No. 3, p. 523.
A.I. Rakhimov, A.V. Nalesnaya, R.V. Fisechko, O.V. Vostrikova, 2006, published in Zhurnal Obshchei Khimii, 2006, Vol. 76,
LETTERS
TO THE EDITOR
Decomposition of Polyfluoroalkyl Chlorosulfites
in the Presence of Copper(I) Chloride
,
,
A. I. Rakhimov* **, A. V. Nalesnaya* **, R. V. Fisechko*, and O. V. Vostrikova*
* Volgograd State Technical University, pr. V.I. Lenina 28, Volgograd, 400131 Russia
e-mail: organic@vstu.ru
** Institute of Chemical Problems in Ecology, Volgograd, Russia
Received April 25, 2005
DOI: 10.1134/S107036320603025X
Alkyl chlorosulfites are formed as intermediates in
reactions of thionyl chloride with alcohols and are re-
adily converted into chloroalkanes. Polyfluoroalkyl
chlorosulfites can be distilled under reduced pressure
without decomposition [1]. On heating to 100 C, these
compounds, like nonfluorinated alkyl chlorosulfites,
lose sulfur dioxide to give polyfluorochloroalkanes [2].
We have found that copper(I) chloride changes the
reaction direction so that decomposition of polyfluoro-
alkyl chlorosulfites leads to formation of bis(poly-
fluoroalkyl) ethers. Presumably, the reaction involves
intermediate formation of a six-membered cyclic
complex.
O
H(CF2CF2)nCH2
H(CF2CF2)nCH2
S
O
Cu2Cl2
[H(CF2CF2)nCH2]2O
2H(CF2CF2)nOS(O)Cl
SOCl2,
SO2
O
Cl
III, IV
I, II
S
Cl
O
n = 1 (I, III), 2 (II, IV).
The reactions were carried out in hexane and
1-hexene. The yield of ether III in 1-hexene was 63%,
and it decreased to 55% in the case of compound IV.
The lower yield of IV is likely to be determined by
greater steric hindrances to complex formation with
the substrate having a longer perfluorinated carbon
chain. The yield of ether IV in hexane was 33%.
1,1,2,2,3,3,4,4-Octafluoro-5-(2,2,3,3,4,4,5,5-
ocktafluoropentoxy)pentane (IV) was synthesized
in a similar way using 1.14 g of copper(I) chloride,
16 ml of 1-hexene, and 7.23 g of chlorosulfite II.
Yield 2.82 g (55%), bp 115 C (4 mm), n2D0 = 1.3401,
d240 = 1.7301; published data [3]: bp 103 C (2 mm),
n2D0 = 1.3385, d240 = 1.7344.
1,1,2,2-Tetrafluoro-3-(2,2,3,3-tetrafluoroprop-
oxy)propane (III). Chlorosulfite I, 7.1 g, was added
at 10 C to a suspension of 1.63 g of copper(I) chlo-
ride in 21 ml of 1-hexene. The mixture was then heated
to 55 C and was kept for 2 h at that temperature. The
coppersalt was filtered, the solvent was distilled off
from the filtrate, and the residue was distilled under
reduced pressure. Yield 2.6 g (63%), bp 65 C (1 mm
Hg), n2D0 = 1.3570, d240 = 1.6270; published data [3]:
bp 65 C (1 mm Hg), n2D0 = 1.3575, d240 = 1.6251.
REFERENCES
1. Rakhimov, A.I. and Vostrikova, O.V., Russ. J. Org.
Chem., 1999, vol. 35, no. 5, p. 794.
2. Rakhimov, A.I. and Vostrikova, O.V., Zh. Prikl. Khim.,
2002, vol. 75, no. 7, p. 1185.
3. Rakhimov, A.I., Nalesnaya, A.V., and Vostrikova, O.V.,
Zh. Prikl. Khim., 2004, vol. 77, no. 9, p. 1573.
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