Features of catalysis in the reaction of polyfluoroalkyl chlorosulfites with saturated monohydric alcohols

Article abstract of DOI:10.1134/S1070363208110169

Synthetic opportunities and mechanism of catalysis of the reaction of polyfluororalkylchlorosulfites with saturated monohydric alcohols are considered. Kinetic measurements and quantum-chemical calculations showed that polyfluoroalkylation of these compou

Full text of DOI:10.1134/S1070363208110169

ISSN 1070-3632, Russian Journal of General Chemistry, 2008, Vol. 78, No. 11, pp. 2075–2081. © Pleiades Publishing, Ltd., 2008.
Original Russian Text © A.I. Rakhimov, A.V. Nalesnaya, R.V. Fisechko, 2008, published in Zhurnal Obshchei Khimii, 2008, Vol. 78, No. 11, pp. 1842–1848.
Features of Catalysis in the Reaction
of Polyfluoroalkyl Chlorosulfites
with Saturated Monohydric Alcohols
A. I. Rakhimova, A. V. Nalesnayaa, and R. V. Fisechkob
a Volgograd State Technical University,
pr. Lenina 28, Volgograd, 400131 Russia
e-mail: organic@vstu.ru
b Institute of Chemical Problems of Ecology, Russian Academy of Natural Sciences, Volgograd, Russia
e-mail: rakhimov@sprint-v.com.ru
Received March 27, 2008
Abstract―Synthetic opportunities and mechanism of catalysis of the reaction of polyfluororalkylchlorosulfites
with saturated monohydric alcohols are considered. Kinetic measurements and quantum-chemical calculations
showed that polyfluoroalkylation of these compounds proceeded through the step of complex formation
involving reagents and catalyst followed by liberation of hydrogen chloride and sulfur dioxide and formation of
polyfluoroalkyl ethers.
DOI: 10.1134/S1070363208110169
We developed a catalytic method for the synthesis
of such ethers that is attractive by technology and
affords product of higher purity.
We have shown earlier that polyfluoroalkyl
chlorosulfites enter into a reaction with alcohols in the
presence of triethylamine affording polyfluoroalkyl
alkyl ethers in 41–52 % yield [1, 2]. This method is
disadvantageous in several respects: low yields and a
contamination by triethylammonium salt of the ether
formed.
The most suitable catalyst for the reaction of
polyfluoroalkyl chlorosulfites with monohydric
alcohols is N,N-dimethylformamide (DMF): the
polyfluoroalkyl alkyl ethers were obtained in the yield
up to 90%. The reaction proceeds along the scheme:
HC(O)N(CH3)2
H(CF2)nCH2OR + SO2 + HCl,
H(CF2)nCH2OS(O)Cl + ROH
II_XII
Ia_Iс
n = 2 (Iа), n = 4 (Ib), n = 6 (Ic); R = p-Pr, n = 4 (II); R = p-Bu, n = 2 (IIIа), n = 4 (IIIb); R = i-Bu, n = 2 (IVа), n = 4 (IVb); R = n-C5H11,
n = 2 (V); R = i-C5H11, n = 2 (VIа), n = 4 (VIb); R = p-C6H13, n = 2 (VIIа), n = 4 (VIIb); R = C6H11 (cyclohexyl), n = 2 (VIIIа), n = 4
(VIIIb), n = 6 (VIIIc); R = PhCH2, n = 2 (IXа), n = 4 (IXb); R = p-Cl-PhCH2, n = 2 (Xа), n = 4 (Xb); R = p-CH3O–PhCH2, n = 2 (XIа),
n = 4 (XIb); R = m-NO2–PhCH2, n = 2 (XIIа), n = 4 (XIIb).
The alcohols were introduced into the reaction as
complexes with DMF. A solution of polyfluoroalkyl
chlorosulfite was charged into a mixture containing
alcohol and DMF in the ratio 1 : (0.005–0.01) mol at
the temperature –10 to –5°C. Then reaction was
performed at 40–50°C for 4–6 h, the sulfur dioxide and
hydrogen chloride liberated were flushed with an inert
gas or dry air. Physicochemical characteristics and
yields of the polyfluoroalkyl alkyl ethers are listed in
Table 1.
By the study of influence of the reaction conditions
on its occurrence we found that elevating the
temperature above 50°C did not lead in the increase in
2075

2076
RAKHIMOV et al.
H
C
Table 1. Phisicochemical characteristics of polyfluoroalkyl
compounds
H
H
CH3
CH3
R
N
C
H
O
Yield,
%
bp, °С
(p, mm Hg)
104 (13)
95 (4)
d420
nD20
O1
Comp. no.
2
4
XIII
87.9
90.0
85.0
60.0
56.0
80.049a
70.0
71.0
60.0
55.0
82.3
75.5
65.2
85.4
83.1
90.2
85.3
70.4
63.7
90.0
84.1
1.4234
1.2770
1.4165
1.1020
1.3040
1.0371
1.0990
1.2990
1.0870
1.2130
1.1005
1.3733
1.4067
1.5065
1.6382
1.4025
1.5002
1.2856
1.3643
1.3570
1.5002
1.3705
1.4180
1.3700
1.3450
1.3520
1.3996
1.3550
1.3600
1.3650
1.3480
1.3798
1.3865
1.3891
1.3580
1.3730
1.4580
1.4100
1.4440
1.3995
1.4760
1.4310
II
IIIa
IIIv
IVа
IVb
V
First step of reaction includes interaction of
associate XIII with molecule I. This results in
formation of six-membered complex XIV on account
of interactions between the atoms О1···C3 and Н2···Cl.
The formation of the complex is favored by a high
electron density on the chlorine atom and a significant
positive charge on the proton in the hydroxy group of
the alcohol:
102 (4)
95 (3)
106 (3)
88 (2)
100 (3)
113 (3)
100 (2)
120 (2)
95 (3)
VIа
VIb
VIIа
VIIb
VIIIа
VIIIb
VIIIc
IXа
IXb
Xа
HF2C
CF2
105 (3)
123 (3)
120 (3)
125 (3)
130 (3)
135 (3)
110 (3)
116 (3)
130 (3)
140 (3)
H
H
C
1
3
O5
O
CH2
R
2 H
Xb
S
O
H3C
H3C
XIа
XIb
XIIа
C
H
N
O
Cl
4
XIV
XIIb
a
Yield of ether in the presence of triethylamine as catalyst [1].
In the second step complex XIV decomposes with
Н2 proton transfer from the alcohol to the polar
chlorine atom with simultaneous cleavage of C3–O5
and S–Cl bonds and the liberation of SO2 and HCl,
regeneration of DMF molecule and the formation of
ether:
the product yield, but, on the contrary, decreased it.
This is due to a side reaction proceeding at elevated
temperature and resulting in
a
symmetrical
polyfluorinated ether:
XIV → ROCH2CF2CF2H + (CH3)2NCHO + SO2 + HCl.
2H(CF2)nCH2OS(O)Cl
→ H(CF2)nCH2OCH2(CF2)nH + SO2 + SOCl2.
Introducing to the alcohol molecule of phenyl or
another substituent with electron–acceptor effect leads
to increase in lability (acidity) of the proton on account
of stronger polarization of Н2–О1 bond. This should
result in increased reactivity of the alcohol in the
reaction with polyfluoroalkyl chlorosulfite.
This reaction pathway becomes predominant when
copper(I) chloride is used as a catalyst [3].
A particular feature of the reaction of chlorosulfites
Ia–Ic with alcohols is the nucleophilic substitution of
the chlorosulfite group by the alkoxy group of the
alcohol with simultaneous liberation of hydrogen
chloride and sulfur dioxide and formation of
polyfluoroalkyl alkyl ether.
The initial reaction rate of the nucleophilic substitu-
tion was measured by the rate of formation of hydrogen
chloride and sulfur dioxide: by differentiation of the
curves of hydrogen chloride and sulfur dioxide
evolution at the time τ→0 we determined initial
reaction rates of 1,1,5-trihydroperfluoropentyl chloro-
sulfite (Ib) with aliphatic (C4H9OH, C5H11OH,
C6H13OH), alicyclic (cyclohexanol), and benzyl
(C6H5CH2OH and its p-CH3O-, p-Cl-, and m-NO2-
derivatives) alcohols at 25, 30 and 35°C (Table 2) [4].
Alcohols possess weak acidic properties, and form
with weak base DMF a donor–acceptor complex
(associate XIII) stable at low temperature.
In the associate XIII due to formation of hydrogen
bonds the Н2−О1 bond is polarized. This bond
elongates and the proton becomes more labile.
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FEATURES OF CATALYSIS IN THE REACTION OF POLYFLUOROALKYL CHLOROSULFITES
2077
Table 2. Initial reaction rates of polyfluoroalkyl chloro-
sulfites with alcohols, v0, min–1
Results of mathematical treatment of the obtained
kinetic curves [4] are listed in Table 3.
Polyfluoro-
Study of reaction of polyfluoroalkyl chlorosulfites
with benzyl alcohols showed that introducing an
electron-donor substituent to aromatic ring decreases
initial reaction rate considerably as compared with
unsubstituted benzyl alcohol (Table 2). The maximal
yield is achieved in the case of m-nitrobenzyl alcohol
(90%), the lowest one with p-methoxybenzyl alcohol
(70.4%). As seen from Table 3, in going from benzyl
alcohol to m-nitrobenzyl derivative the reaction rate
constant grows 1.5-fold and activation energy falls by
5 kcal mol–1 that indicates higher reactivity of the latter
compound. The chlorine substituent in the aromatic
ring also increases reaction rate constant and decreases
the activation barrier. The introduction of a methoxy
group, on the contrary, decreases reaction rate constant
and increases the activation energy. Thus, it seems
obvious, that introducing electron-acceptor substi-
tuents to the aromatic ring increases both initial rate
and yield of ether as compared with unsubstituted
benzyl alcohol on account of increase in the alcohol
acidity, while electron–donor substituents, on the
contrary, decrease the initial rate and product yield.
Reaction temperature, °С
Alcohol
alkyl
25
30
35
chlorosulfite
–
0.0326
0.0249
–
Iа
Butan-1-ol
0.0189
0.0279
Ib
–
0.0235
0.0169
–
Iа
Pentan-1-ol
Hexan-1-ol
Cyclohexanol
0.0140
0.0234
Ib
–
0.0128
0.0094
0.0098
0.0088
–
Iа
Ib
Iа
Ib
0.0087
0.0101
–
–
–
–
Benzyl
–
–
–
0.0211
0.0158
0.0230
–
–
–
Ib
Ib
Ib
p-Metoxybenzyl
p-Chlorobenzyl
m-Nitrobenzyl
–
0.0260
–
Ib
Hence, the kinetics study confirms the assumption that
introducing to alcohol molecule electron-withdrawing
groups leads to increase in the reaction rate and
decrease in the activation barrier. However, on the one
hand, introducing electron–acceptor groups decreases
electron density on the oxygen atom that leads to a
decrease in the alcohol nucleophilicity and thus retards
its association with the carbon atom in polyfluoroalkyl
chlorosulfite, and on the other hand, introducing the
electron–acceptor group leads to a significant increase
in the positive charge on the hydroxy hydrogen atom
and to increase in polarity of Н–О bond in the alcohol–
DMF associate XIII, which in turn leads to increase in
the proton mobility. Thus, the more mobile proton of
the alcohol hydroxy group, the easier its association
with chlorine atom, and the reaction proceeds faster.
Higher acidity of hydroxy group in m-nitrobenzyl
alcohol as compared with benzyl alcohol leads to
higher polarization of Н–О bond and to easier
formation of associate with DMF that causes the
transfer of more labile proton and liberation of HCl
and SO2 molecules at the decomposition of complex
XIV. Electron-releasing methoxy group, on the
contrary, reduces the acidity of the alcohol hydroxy
group, that is, decreases the proton mobility and
retards the formation of complex XIV.
Thus, activation energy is maximal for cyclo-
hexanol and minimal for m-nitrobenzyl alcohol.
Table 3. Kinetic parameters of reaction of alcohols with 1,1,5-trihydroperfluoropentyl chlorosulfite
k×103, mol l–1 s–1
Еа,
kcal mol–1
Еа(calc)
,
Alcohol
n
kcal mol–1 a
25°С
30°С
35°С
Butan-1-ol
0.06
0.04
0.03
0.02
0.08
0.05
0.10
0.10
0.21
0.18
0.14
0.08
0.25
0.21
0.29
0.31
0.33
0.25
0.21
0.12
0.38
0.32
0.40
0.41
31.0
32.2
33.0
42.9
25.5
28.6
21.4
21.05
37.05
1.87
1.69
2.01
–
Pentan-1-ol
–
Hexan-1-ol
41.53
Cyclohexanol
Benzyl alcohol
p-Metoxybenzyl
p-Chlorobenzyl
m-Nitrobenzyl
–
25.3
–
2.3
–
–
–
–
–
a Calculated by quantum-chemical ab initio method.
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2078
RAKHIMOV et al.
Probably the proton transfer is the limiting factor
defining the readiness of formation of the reaction
products. For aliphatic alcohols the rate of transfer is
low and elongation of aliphatic chain leads to lower
acidity of the alcohol resulting in the increase in
activation barrier of the reaction. Benzyl alcohols are more
acidic, and reaction rate with these alcohols is higher.
–30°C from solutions in CDCl3, internal reference
TMS. For comparison, Н NMR spectra were also
1
registered of the parent 1,1,5-trihydroperfluoropentyl
chloro-sulfites and alcohols. In the spectrum of
compound Ib appear two triplets corresponding to the
protons of methylene groups. By our assumption, the
presence of two triplets can be explained by the
existence of Ib in two conformations differing by the
mutual positions of the protons of methylene group
relatively to chlorine and oxygen atoms. At low
temperatures the conformational transformations are
frozen and the proton signals are split. Due to direct
interactions of hydrogen atom Н2 in the complex XIV
with oxygen atom of DMF and chlorine atom of 1,1,5-
trihydroperfluoropentyl chlorosulfite, in 1Н NMR
spectrum occurs downfield shift of the signal of this
proton. The signal of CН2-group protons in Ib at the
carbon atom entering in the reaction with the oxygen
atom bearing extra electron density is shifted upfield as
compared with isolated molecule Ib evidencing the
formation of the complex.
Thus, the activity of alcohols falls in the series:
butanol–pentanol–hexanol, the hydrocarbon chain
elongation leads to the decrease in the initial reaction
rate. Maximal yield is reached with butanol and
pentanol: 90 and 80 %, respectively. Branching of the
alcohol hydrocarbon chain retards reaction and
decreases yield, probably due to steric hindrances. The
chain elongation to C6 also decreases yield consid-
erably (to 60%).
We showed experimentally that reaction of poly-
fluoroalkyl chlorosulfites with secondary alcohols
under the same conditions did not occur, probably due
to steric hindrances. However, we found that
cyclohexanol enters in the reaction affording the ether
in high yield (up to 82%). That is understandable in
keeping with the features of its structure. The
As seen from Table 4 the shifts of signals of the
protons involved into formation of the complex and
located at a carbon atom depend on the nature of
alcohol. For the complex with butanol the shift of
methylene group protons of Ib is 0.87 ppm, that of
hydoxy group proton 0.17 ppm. In the case of benzyl
alcohol these shifts are larger: for methylene protons of
Ib 0.98 ppm, for hydroxy proton 0.29 ppm. This
indicates higher polarization of the intermediate
complex formed by benzyl alcohol.
cyclohexanol exists predominantly in
a
more
energetically favorable chair conformer with equa-
torial hydroxy group, more accessible for the reaction
with polyfluoroalkyl chlorosulfite, in contrast to the
hydroxy group in aliphatic secondary alcohols.
Nevertheless, reactivity of cyclohexanol is 1.3-fold
below that of hexanol.
By the method of 1Н NMR spectroscopy we
elucidated structure of six-membered complex XIV on
the example of reactions of butanol and benzyl
alcohols with 1,1,5-trihydroperfluoropentyl chloro-
sulfite (Ib) (Table 4). The spectra were registered at
The assumed reaction mechanism that includes
formation of complex XIV allows to relate the alcohol
acidity and its reactivity: the increase in the acidity of
an alcohol leads to its higher reactivity.
Table 4. 1H NMR spectrum of XIV
Chemical shift, δ and spin–spin coupling constant, J
Complex
HCF2
O–CH2–CF2
HO–
Ph–
δ, ppm
J, Hz
51.9
5.4
δ, ppm
3.850 t
3.645 t
3.995 t
3.532 t
4.065 t
4.515 t
–
J, Hz
14.6
12.6
15.3
13.2
12.0
12.3
–
δ, ppm
δ, ppm
Complex with butan-1-ol
Complex with benzyl alcohol
Ib
5.735 t.t
3.10 s
4.209 s
–
–
7.16 m
–
53.1
3.9
5.611 t.t
5.907 t.t
52.5
3.9
Butan-1-ol
–
–
–
2.93 s
3.92 s
–
Benzyl alcohol
–
–
–
7.15 m
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 78 No. 11 2008

FEATURES OF CATALYSIS IN THE REACTION OF POLYFLUOROALKYL CHLOROSULFITES
2079
By quantum-chemical ab initio method with 3-21G
basis (from H to Ar) [5] we calculated a model of
reaction of 1,1,3-trihydroperfluoropropyl chlorosulfite
with various alcohols in the presence of DMF.
Thus, the quantum-chemical calculation also
confirms that introducing electron-acceptor group to
the alcohol molecule diminishes considerably ener-
getic barriers and stipulates reaction proceeding on
account of increased polarization of О–Н bond and the
formation of stronger associates with DMF. Reactivity
of butanol is much lower owing to weak polarization
of О–Н bond. Calculated and experimental activation
energies (Table 3) are close by value pointing to high
probability of the proposed mechanism.
Association of alcohol with DMF (XIII) proceeds
on account of formation of hydrogen bonds between
the atoms Н1–О2 and Н2–О2 and is energetically advan-
tageous because leads to energy gain matching the value
known for hydrogen bonding: ΔЕ = –3.12 kcal mol–1
(butanol), ΔЕ = –6.10 kcal mol–1 (benzyl alcohol).
On the basis of these quantum-chemical calcula-
tions and kinetic investigations we may conclude that
the reaction of polyfluoroalkyl chlorosulfites with alco-
hols evidently proceeds along the bimolecular mecha-
nism of nucleophilic substitution of chlorosulfite group
by alkoxy anion. Introducing electron-acceptor substi-
tuents to the alcohol molecule increases the reaction rate
and decreases the activation energy. Thus, when the
alcohol acidity is higher its reactivity in the catalytic
reaction with polyfluoroalkyl chlorosulfite grows.
Formation of six-membered complex XIV that
includes polyfluoroalkyl chlorosulfite, alcohol and
DMF proceeds via interaction between the atoms: H1–
Cl, O1–C3. The oxygen atom of alcohol involved into
attack at the carbon atom of CН2-group bears higher
electron density than in the parent alcohol, that is, an
energy gain is achieved: ΔЕ = –1.94 kcal mol–1
(butanol), ΔЕ = –2.88 kcal mol–1 (benzyl alcohol ).
At the thermolysis of six-membered complex the
proton of alcohol is transferred to the negatively
charged chlorine atom and simultaneously C–O and S–
Cl bonds are ruptured with liberation of SO2 and HCl
molecules and regeneration of DMF molecule. This
step has an energetic barrier Еa = 38.058 kcal mol–1
(butanol) or 25.341 kcal mol–1 (benzyl alcohol ).
EXPERIMENTAL
The 1Н NMR spectra (300 MHz) were registered on
a Varian Mercury-300 instrument, solvents CDCl3 and
CCl4, internal reference tetramethylsilane. IR spectra
were registered on a Specord-M82 spectrophotometer
from thin liquid film.
Table 5 shows changes in charges on the atoms
involved in the formation of complex XIV.
As seen from Table 5 in going from butanol to
benzyl alcohol the positive charge on the hydroxy
group hydrogen atom rises leading to elongation of Н–
О bond and increased proton mobility. Simultaneously
in going from butanol to benzyl alcohol rises the
electron density on the chlorine atom of poly-
fluoroalkyl chlorosulfite that makes easier association
of the hydroxy group proton with the chlorine atom,
and this association in turn promotes proton transfer
with formation of the hydrogen chloride molecule.
Polyfluoroalkyl ethers (II–XII). 0.023 mol of
alcohol was mixed with 0.00023 mol of DMF in 20 ml
of a solvent (hexane, chloroform, or, in the case of
benzyl alcohols, benzene), the mixture was cooled to
–5°C and 0.024 mol of polyfluoroalkyl chlorosulfite
Ia–Ic in 15 ml of solvent was added by portions to the
solution at vigorous stirring, maintaining the tem-
perature –5°C. After mixing the reagents, the mixture
temperature was increased to 45–50°C, and the
mixture was kept for 6 h at continuous passage of inert
Table 5. Changes in atomic charges of the atoms involved in formation of XIV
Charge value
Bond length, Å
–Н
Complex
–С–
–О–
–Сl
О–Н
–S–Cl
НО-group
of alcohol
+0.197
–СН2 in Ia
of alcohol
in Ia
In alcohol
in Ia
With butan-1-ol
initial
–0.004
–0.007
–0.004
–0.005
–0.330
–0.363
–0.325
–0.380
–0.361
–0.393
–0.361
–0.398
0.9637
0.9678
0.9641
0.9825
2.0111
2.0237
2.0111
2.0285
in the complex
initial
+0.223
With benzyl
alcohol
+0.197
in the complex
+0.235
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 78 No. 11 2008

2080
RAKHIMOV et al.
1
gas (nitrogen). Then solvent was distilled off, and the
product was distilled in a vacuum.
vibrations). Н NMR spectrum, δ, ppm: 5.95 t.t (1Н,
HCF2); 3.86 t (2Н, O–CН2–CF2), 2.85 s (CH ring),
1.74 and 1.32 (ring multiplet).
1-(2,2,3,3,4,4,5,5-Octafluoro)pentoxypropane (II).
Yield 87.9%, bp 104°C (13 mm Hg), nD20 1.3705, d420
1.4234. IR spectrum, ν, cm–1: 1154 (C–О–C), 1180
(CF2), 2892 (CH2–O), 2980 (CH2, CH3).
2,2,3,3,4,4,5,5-Octafluoropentoxycyclohexane
(VIIIb). Yield 75.5%, bp 105°C (3 mm Hg), nD20
1.3865, d420 1.3733. IR spectrum, ν, cm–1: 1165 m
[ν(C–О–C)]; 1185 s [ν(CF2)]; 2870, 2960 [ν(CH2)];
3005 w (CHF2), 716 m, 763 m, 810 m, 960 m (vibra-
1-(2,2,3,3-Tetrafluoro)propyloxybutane (IIIa).
Yield 90.0%, bp 95°C (4 mm Hg), nD20 1.4180, d420
1.2770. IR spectrum, ν, cm–1: 1171 (C–O–C), 1206
(CF2), 2912 (O–CH2), 2963 (CH2), 2997 (CH3).
1
tions ring). Н NMR spectrum, δ, ppm: 5.99 t.t (1Н,
HCF2); 3.95 t (2Н, O–CН2–CF2), 2.89 s (CH ring),
1.75 and 1.31 (ring multiplet).
1-(2,2,3,3,4,4,5,5-Octafluoro)pentoxybutane (IIIb).
Yield 85.0%, bp 102°C (4 mm Hg), nD20 1.3700, d420
1.4165. IR spectrum, ν, cm–1: 1179 (C–O–C), 1216
(CF2), 2928, 2966 (CH2), 3004 (CF2H).
2,2,3,3,4,4,5,5,6,6,7,7-Dodecafluoroheptyloxy-
cyclohexane (VIIIc). Yield 65.2%, bp 123°C (3 mm
Hg), nD20 1.3891, d420 1.4067. IR spectrum, ν, cm–1: 1165
m [ν(C–О–C)]; 1185 s [ν(CF2)]; 2870, 2960 [ν(CH2)];
3005 w (CHF2), 716 m, 763 m, 810 m, 960 m (ring
vibrations).
1-(2,2,3,3-Tetrafluoropropyloxy)-2-methylpropane
(IVa). Yield 60.0%, bp 95°C (3 mm Hg), nD20 1.3450,
d420 1.1020. IR spectrum, ν, cm–1: 1170 (C–O–C), 1210
(CF2), 2930, 2966 (CH2), 3001 (CF2H).
[(2,2,3,3-Tetrafluoropropyloxy)methyl]benzene
(IXa). Yield 85.4%, bp 120°C (3 mm Hg), nD20 1.3580,
d420 1.5065. IR spectrum, ν, cm–1: 1160m [ν(C–О–C)];
1200с [ν(CH2)]; 3050 [ν(CH2)]; 1456 m, 1500 m (Ph).
1Н NMR spectrum, δ, ppm: 5.96 t.t (1Н, HCF2); 4.37 t
(2Н, O–CН2–CF2), 7.39 multiplet (Ph) 4.32 s (Ph–CН2).
1-(2,2,3,3,4,4,5,5-Octafluoropentoxy)-2-methylpro-
pane (IVb). Yield 56.0%, bp 106°C (3 mm Hg), nD20
1.3520, d420 1.3040. IR spectrum, ν, cm–1: 1169 (C–O–
C), 1215 (CF2), 2930, 2968 (CH2), 3009 (CF2H).
1-(2,2,3,3-Tetrafluoropropyloxy)pentane (V). Yield
80%, bp 88°C (2 mm Hg), nD20 1.3996, d420 1.0371. IR
spectrum, ν, cm –1: 1169 (C–O–C), 1214 (CF2), 2885
(CH2), 2963 (CF2H).
[(2,2,3,3,4,4,5,5-Octafluoropentoxy)methyl]-
benzene (IXb). Yield 83.1%, bp 125°C (3 mm Hg),
nD20 1.3730, d420 1.6382. IR spectrum, ν, cm–1: 1163m [ν
(C–О–C)]; 1210s [ν(CF2)]; 3051 [ν(CH2)]; 1460 m,
1500 m (Ph).
1-(2,2,3,3-Tetrafluoropropyloxy)-3-methylbutane
(VIa). Yield 70.0%, bp 113°C (3 mm Hg), nD20 1.3550,
d420 1.0990. IR spectrum, ν, cm–1: 1171 (C–O–C), 1210
(CF2), 2885 (CH2), 2965 (CF2H).
1-Chloro-4-[(2,2,3,3-tetrafluoropropyloxy)me-
thyl]benzene (Xa). Yield 90.2%, bp 130°C (3 mm
Hg), nD20 1.4580, d420 1.4025. IR spectrum, ν, cm–1:
1168 m [ν(C–О–C)]; 1195 w [ν(CF2)]; 3050 [ν(CH2)];
1470 m, 1550 m (Ph), 810 m (Cl). Н NMR spectrum,
δ, ppm: 5.97 t.t (1Н, HCF2); 3.34 t (2Н, O–CН2–CF2),
7.21 m (Ph), 4.42 s (Ph–CН2).
1-(2,2,3,3,4,4,5,5-Octafluoropentoxy)-3-met h y l -
butane (VIb). Yield 71.0%, bp 100°C (2 mm Hg), nD20
1.3600, d420 1.2990. IR spectrum, ν, cm–1: 1175 (C–O–
C), 1210 (CF2), 2890 (CH2), 2969 (CF2H).
1
1-(2,2,3,3-Tetrafluoropropyloxy)hexane (VIIa).
Yield 60.0%, bp 100°C (2 mm Hg), nD20 1.3650, d420
1.0870. IR spectrum, ν, cm–1: 1174 (C–O–C), 1211
(CF2), 2890, 2967 (CH2), 2970 (CF2H).
1-Chloro-4-[(2,2,3,3,4,4,5,5-octafluoropentoxy)-
methyl]benzene (Xb). Yield 85.3%, bp 135°C (3 mm
Hg), nD20 1.4100, d420 1.5002. IR spectrum, ν, cm–1: 1167
m [ν(C–О–C)]; 1190 w [ν(CF2)]; 3055 [ν(CH2)]; 1475
m, 1552 m (Ph), 808 m (Cl).
1-(2,2,3,3,4,4,5,5-Octafluoro)pentoxyhexane (VIIb).
Yield 55.0%, bp 120°C (2 mm Hg), nD20 1.3480, d420
1.2130. IR spectrum, ν, cm–1: 1170 (C–O–C), 1212
(CF2), 2860, 2970 (CH2), 2975 (CF2H).
1-Methoxy-4-[(2,2,3,3-tetrafluoropropyloxy)me-
thyl]benzene (XIa). Yield 70.4%, bp 110°C (3 mm
Hg), nD20 1.4440, d420 1.2856. IR spectrum, ν, cm–1: 1200
m [ν(C–О–C)]; 1200 w [ν(CF2)]; 3025 [ν(CH2)]; 1600
2,2,3,3-Tetrafluoropropyloxycyclohexane (VIIIa).
Yield 82.3%, bp 95°C (3 mm Hg), nD20 1.3798, d420
1.1005. IR spectrum, ν, cm–1: 1170m [ν(C–О–C)];
1170 s [ν(CF2)]; 2878 m, 2965 m [ν(CH2)]; 3005 w
(CHF2), 714 m, 760 m, 800 m, 1000 m (ring
1
m, 1516 m (Ph). Н NMR spectrum, δ, ppm: 5.94 t.t
(1Н, HCF2); 4.41 t (2Н, O–CН2–CF2), 6.73 and 7.14 d
(Ph), 4.41 s (Ph–CН2), 3.69 s (OCH3).
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 78 No. 11 2008

FEATURES OF CATALYSIS IN THE REACTION OF POLYFLUOROALKYL CHLOROSULFITES
2081
m [ν(C–О–C)]; 1850 w [ν(CF2)]; 3030 [ν(CH2)]; 1455
m, 1511m (Ph), 1324 m (NO2).
1-Methoxy-4-[(2,2,3,3,4,4,5,5-octafluoropentoxy)-
methyl]benzene (XIb). Yield 63.7%, bp 116°C (3 mm
Hg), nD20 1.3995, d420 1.3643. IR spectrum, ν, cm–1: 1205
m [ν(C–О–C)]; 1200 w [ν(CF2)]; 3030 [ν(CH2)]; 1610
m, 1510 m (Ph).
REFERENCES
1. Rakhimov, A.I., Nalesnaya, A.V. and Vostrikova, O.V.,
Zh. Obshch. Khim., 2004, vol. 74, no. 4, p. 967.
2. Rakhimov, A.I., Nalesnaya, A.V., and Vostrikova, O.V.,
Zh. Prikl. Khim., 2004, vol. 77, no. 9, p. 1573.
3. Rakhimov, A.I., Nalesnaya, A.V., Fisechko, R.V., and
Vostrikova, O.V., Zh. Obshch. Khim., 2006, vol. 76,
no. 3, p. 523.
4. Fisechko, R.V., Candidate Sci. (Chem.) Dissertation,
Volgograd: 2007.
1-Nitro-3-[(2,2,3,3-tetrafluoropropyloxy)methyl]-
benzene (XIIa). Yield 90.0%, bp 130°C (3 mm Hg),
nD20 1.4760, d420 1.3570. IR spectrum, ν, cm–1: 1170 m
[ν(C–О–C)]; 1850 w [ν(CF2)]; 3025 [ν(CH2)]; 1450 m,
1
1510 m (Ph), 1320 m (NO2). Н NMR spectrum, δ,
ppm: 5.93 t.t (1Н, HCF2); 4.40 t (2Н, O–CН2–CF2),
7.45 m (Ph) 4.42 s (Ph–CН2).
1-Nitro-3-[(2,2,3,3,4,4,5,5-octafluoropentoxy)me-
thyl]benzene (XIIb). Yield 84.1%, bp 140°C (3 mm
Hg), nD20 1.4310, d420 1.5002. IR spectrum, ν, cm–1: 1175
5. Schmidt, M.W., Baladrige, K.K., and Boatz, J.A.,
J. Comput. Chem., 1993, vol. 14, p. 1347.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 78 No. 11 2008