Preparation of the first ortho-substituted pentafluorosulfanylbenzenes

Article abstract of DOI:10.1016/S0022-1139(01)00514-0

The preparation of the first ortho-substituted pentafluorosulfanylbenzenes was achieved. Oxidative fluorination (AgF₂) of a series of aromatic disulfides containing different substituents ortho to the disulfide moiety gave only one ortho-substi

Full text of DOI:10.1016/S0022-1139(01)00514-0

Journal of Fluorine Chemistry 112 02001) 287±295
Preparation of the ®rst ortho-substituted penta¯uorosulfanylbenzenes
Alexey M. Sipyagina,b, Colin P. Batemana, Ying-Teck Tana, Joseph S. Thrashera,*
aDepartment of Chemistry, The University of Alabama, P.O. Box 870336, Tuscaloosa, AL 35487-0336, USA
bInstitute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Moscow Region, Russia
Received 16 July 2001; accepted 31 August 2001
Abstract
The preparation of the ®rst ortho-substituted penta¯uorosulfanylbenzenes was achieved. Oxidative ¯uorination 0AgF2) of a series of
aromatic disul®des containing different substituents ortho to the disul®de moiety gave only one ortho-substituted SF5-benzene, namely 1-
¯uoro-4-nitro-2-penta¯uorosulfanylbenzene. This compound has been transformed into a variety of other ortho-substituted SF5-benzenes by
nucleophilic substitution reactions. # 2001 Published by Elsevier Science B.V.
Keywords: Penta¯uorosulfanylbenzene; Sulfur halogen compounds; Fluorine and compounds; Coupling reactions
1. Introduction
materials. For example, Williams and Foster at Zeneca were
able to improve upon Sheppard's method primarily by
switching to alternate solvents such as alkanes, per¯uor-
oalkanes, and per¯uoroalkylethers [10]. In the mid-1990s,
BNFL ¯uorochemicals, which has now become F2 chemi-
cals, developed and patented a vastly improved procedure
for preparing certain SF5-benzenes via the direct ¯uorination
of either aromatic thiols or disul®des in a suitable solvent
such as anhydrous acetonitrile [11±13]. More recently,
Philp and co-workers have collaborated with F2 chemicals
to expand upon this chemistry [14], while Chambers and
co-workers have collaborated with BNFL in the develop-
ment of microreactors for use with elemental ¯uorine
[15,16]. Penta¯uorosulfanylbenzenes were prepared in these
microreactors.
As SF5-benzenes became easier to prepare, an ever-
increasing number of publications 0primarily patents) appea-
red describing a variety of applications for these materials.
These applications have ranged from liquid crystals [17±24]
to pesticides [25±30], with the latter application sometimes
being more speci®cally de®ned as herbicides [31±34], fun-
gicides [35±37], parasiticides [38±41], and insecticides/
acaricides/arthropodicides [36,42±46]. Interestingly, two
of the most recent examples cover the use of SF5-arylpyr-
azoles to ®ght ¯ea and tick infestation in animals [47,48].
Even with these advances, no general procedure exists for
preparing SF5-benzene derivatives with a substituent other
than hydrogen ortho to the SF5 group. In fact, to the best of
our knowledge, only one such compound actually existed
prior to this work, namely 1,2,4-tris-penta¯uorosulfanylben-
zene. Seppelt and co-workers prepared this SF5-benzene
Recent years have been marked by a considerable
increase in the interest of penta¯uorosulfanylbenzene deri-
vatives as evidenced by their inclusion in articles on the ®ne
chemicals industry [1,2]. This interest has largely been
spawned by signi®cant improvements in the methods for
preparing these compounds as well as the existence of a
more diverse set of applications. Both meta-nitro- and para-
nitro-SF5-benzene have been commercially available for
several years.
Sheppard prepared the ®rst penta¯uorosulfanylbenzenes
in the early 1960s via the reaction of an aromatic disul®de
with silver di¯uoride in a suspension of a chloro¯uorocarbon
solvent [3,4]. Raasch, a colleague of Sheppard's at DuPont,
patented several ureido-substituted SF5-benzenes based on
their biological activity as plant regulants, herbicides, and
bactericides [5]. Although Sheppard and Raasch carried out
their reactions in copper autoclaves, it does not appear that
they knew the signi®cance of this choice. For a number of
years we have been utilizing Sheppard's method to prepare
more highly functionalized SF5-benzenes for applications in
the areas of polymer chemistry as well as biological activity
[6±8]. We have come to learn that copper, as well as other
noble metals, facilitate this reaction via the intermediacy of
metal aryl thiolates [9].
At the same time, others have either improved upon
Sheppard's method or developed alternate routes to these
* Corresponding author. Tel.: ‡1-205-348-8434; fax: ‡1-205-348-8448.
E-mail address: fluorine@bama.ua.edu 0J.S. Thrasher).
0022-1139/01/$ ± see front matter # 2001 Published by Elsevier Science B.V.
PII: S 0 0 2 2 - 1 1 3 9 0 0 1 ) 0 0 5 1 4 - 0

288
A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
Table 1
derivative via the dicobalt octacarbonyl catalyzed trimeriza-
tion of SF5±CBC±H [49]. Furthermore, neither direct
¯uorination nor oxidative ¯uorination 0with AgF2) of
bis-2-nitrophenyl disul®de gave ortho-nitro-SF5-benzene
[4,11±14]. Only ortho-nitro-SF3-bezene resulted from these
attempts, and its decomposition occurred when more forcing
reaction conditions were used. Presumably, steric hindrance
from the ortho-nitro group prevents further ¯uorination of
the SF3 moiety. Almost 40 years ago Sheppard suggested
``that steric interactions would occur between the ¯uorines
0of a SF5 group) and an ortho-substituent of atomic radius
greater than hydrogen or ¯uorine [4]''. The goal of the
study reported herein is the preparation of SF5-benzenes
containing an ortho-substituent other than a hydrogen atom.
Preparation of disulfides 1a±e
Compound 1
Reaction
Yield
mp 08C)
time 0h)
0%)
a
b
c
24
24
36
36
24
82
84
85
90
86
124±126
40±41
142±144 0143±143.5) [58]
157±159 0159±161) [59]
187±188.5
d
e
0.037 mol of disul®de to 1.0 mol of AgF2. After the ¯uor-
ination was completed, the reaction mixture was extracted
with chloroform and washed with an aqueous solution of
NaHCO3. The product mixture was analyzed by TLC and
gas chromatograph±mass spectrometer 0GC±MS), and the
mixture was separated on a silica gel column. The presence
of the SF5 moiety was easily veri®ed not only by GC±MS but
also by 19F NMR spectroscopy 0a prototypical AB4 spin
pattern with an asymmetric nonet at ca. 80±83 ppm and a
doublet of multiplets at ca. 63±65 ppm with a coupling
constant of ca. 150±152 Hz [50]).
Our study revealed evidence of a SF5-containing derivative
only in the case of disul®de 1a 0see Scheme 1). Evidently, the
presence of the NO2 group on the aromatic ring during the
¯uorination turns out to be essential, as the ¯uorination of
disul®de 1b, which contains a Br atom instead of a NO2
group, gave no evidence of any SF5-containing products
under identical reaction conditions to those used for 1a. In
all other reactions, complex product mixtures were obtained
2. Results and discussion
In an effort to investigate the possibility of having a
substituent other than hydrogen ortho to the eventual SF5
group in a benzene derivative, a series of symmetrical 4,40-
dinitrophenyl disul®des 1a±e was prepared 0see Tables 1 and
2). These disul®des possessed substituents of gradually
increasing size adjacent to the disul®de linkage: F, Cl, Br
and 4-nitrophenyl. In all cases, except compound 1b, deac-
tivating nitro groups were used to protect the aromatic ring.
All ¯uorination reactions were carried out under standard
conditions in a passivated 0with F2) stainless steel reactor
with intermittent shaking and within a temperature range of
60 8C 02 h) to 125±130 8C 03 h). The ratio of reagents was
Table 2
Spectral data of compounds 1a±e
Compound 1H NMR 0d)
13C NMR 0d)
MS m/z 0%)
HRMS
Calculated Formula
Found
‡
a
7.27 01H, m), 81.19 01H, m),
8.53 01H, m)
117.0 0d, J ˆ 24.3 Hz),
125.3 0d, J ˆ 19.7 Hz),
125.8 0d, J ˆ 9.4 Hz),
126.5, 144.7 0broad s),
163.7 0d, J ˆ 257.8 Hz)
117.2 0d, J ˆ 3.5 Hz),
117.5 0d, J ˆ 23.2 Hz),
125.4 0d, J ˆ 18.8 Hz),
344 0M , 92), 173
‡
343.974
C12H6F2O4S2
343.974
0M /2 ‡ 1, 100),
‡
172 0M /2, 32), 126 095)
‡
b
6.96 01H, t, J ˆ 8.8 Hz),
7.38 01H, m), 7.69 01H, dd,
J ˆ 2.4, 6.6 Hz)
414 0M ‡ 4, 41),
409.825
C12H675Br2F2S2
409.826
‡
412 0M ‡ 2, 75),
‡
410 0M , 40), 252 011),
‡
‡
132.8 0d, J ˆ 7.7 Hz), 133.4, 207 0M /2 ‡ 2, 27),
159.6 0d, J ˆ 248.0 Hz)
205 0M /2, 26), 126 0100)
413.821
375.915
C
12H681Br2F2S2
C12H635Cl2O4S2
413.822
375.914
‡
c
d
e
7.60 01H, d, J ˆ 8.5 Hz),
8.06 01H, dd, J ˆ 2.5, 8.5 Hz),
8.44 01H, d, J ˆ 2.5 Hz)
376 0M , 100), 360 012),
346 06), 298 09), 267 019),
‡
237 034), 189 0M /2 ‡ 1, 71),
‡
188 0M /2, 64)
‡
7.77 01H, d, J ˆ 8.5 Hz),
7.96 01H, dd, J ˆ 2.4, 8.5 Hz),
8.40 01H, d, J ˆ 2.4 Hz)
466 0M , 100), 450 08),
306 034), 283 08), 260 018),
465.812
550.025
C12H679Br81BrO4S2 465.812
‡
234 028), 233 M /2, 35),
232 028), 230 024), 214 024)
‡
7.46 01H, d, J ˆ 8.4 Hz), 7.62 121.0, 122.4, 124.1, 130.2,
02H, m), 8.16 01H, dd, J ˆ 2.2, 131.3, 136.5, 143.3, 145.0,
550 0M , 31), 534 05),
‡
C24H14N4O8S2
550.025
518 06), 276 0M /2 ‡ 1, 100),
‡
8.4 Hz), 8.40 02H, m), 8.43
01H, d, J ˆ 2.2 Hz)
148.4, 148.6
275 0M /2, 43), 259 035),
258 031), 244 027)

A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
289
Scheme 1.
that did not give any evidence of the presence of a SF5-
containing product. Perhaps the ¯uorinations were halted at
the stage of the SF3 derivative, which would have been easily
hydrolyzed during work up with the aqueous NaHCO3.
However, compounds 1b±d can interact with AgF2 in other
ways. For instance, ¯uorination of the benzene ring could
occur as well as intramolecular and/or intermolecular oxi-
dation±reduction processes with NO2 groups [4].
The successful ¯uorination of disul®de 1a was carried out
as described, and compound 2 was isolated in 18.4% yield.
Its structure was con®rmed by spectroscopic and analytical
analyses 0see Section 3 and Tables 3±5). For example, the
19F NMR spectrum of 2 reveals three multiplets: two belong
to the resonances of the SF5 group at 77.95 ppm 0axial
¯uorine) and 67.80 ppm 0equatorial ¯uorines, dd,
2J ˆ 151:6 Hz, 4J ˆ 24:7 Hz), while the third multiplet
belonging to the resonance of the ring ¯uorine is a quintet
at À97.41 ppm 04J ˆ 24:7 Hz). In comparison to the usual
19F NMR spectra of SF5-benzenes, this spectrum shows the
additional coupling between the ring ¯uorine and the equa-
torial ¯uorine atom. The ortho ring ¯uorine atom also shifts
the resonances of the equatorial ¯uorine atoms to stronger
®eld by about 3±5 ppm.
In the 13C NMR spectrum of compound 2, the resonance of
the ipso carbon to the SF5 group appears as a doublet of
quintets as a result of spin±spin coupling with both the ortho
ring ¯uorine atom and the four equatorial ¯uorine atoms of
the SF5 group. The down®eld doublet with J ˆ 271:5 Hz
belongs to the C-1 carbon atom, and the broad signal at d
143.5 ppm can be assigned to the C-4 carbon atom connected
to the NO2 group. The other three resonances: a doublet at d
129.0 ppm 0J ˆ 11:2 Hz), multiplet at d 125.2 ppm, and
strong®eld doublet at d 119.3 ppm 0J ˆ 26:0 Hz) can be
assigned to C-5, C-3 and C-6, respectively.
The 1H NMR spectrum of compound 2 displays three sets
of signals of equal intensity. The signal at 8.71 ppm is a
Table 3
1H and 19F NMR spectral data for compounds 2±7
Compound 1H NMR 0d, ppm)
19F NMR 0d, ppm)
Benzene protons
Others
SF5
Others
H-6
H-5
H-3
Axial
Equatorial
2
7.47 0m, J ˆ 8.7, 5.9 Hz)
8.47 0m)
8.71 0dd, J ˆ
5.9, 2.7 Hz)
8.69 0d, J ˆ
2.2 Hz)
77.95 0m, J ˆ 67.84 0dm, J ˆ
151.6 Hz) 151.6, 24.7 Hz)
81.90 0m, J ˆ 65.07 0dm, J ˆ
152.0 Hz) 152.0 Hz)
82.13 0m, J ˆ 66.95 0dm, J ˆ
150.5 Hz) 150.5 Hz)
À97.41 0m, J
ˆ 24.7 Hz)
3a
3b
4
7.44 0d, J ˆ 8.9 Hz)
7.28 0d, J ˆ 9.0 Hz)
7.14 0d, J ˆ 9.2 Hz)
8.26 0dd, J ˆ
8.9, 2.2 Hz)
8.13 0dd, J ˆ
8.8, 2.3 Hz)
8.35 0dd, J ˆ
9.2, 2.7 Hz)
2.63 03H, s)
8.76 0d, J ˆ
2.4 Hz)
7.66 02H, d,
J ˆ 8.9 Hz)
8.68 0d, J ˆ
2.7 Hz)
1.53 03H, t,
82.04 0m, J ˆ 67.61 0dm, J ˆ
J ˆ 7.0 Hz),
4.28 02H, q,
J ˆ 7.0 Hz)
151.8 Hz)
151.8 Hz)
5
7.63 0d, J ˆ 8.8 Hz)
8.35 0dd, J ˆ
8.70 0d, J ˆ
1.61 02H, m),
1.73 04H, t, J ˆ
5.7 Hz), 2.8 04H,
t, J ˆ 4.8 Hz)
80.95 0m, J ˆ
66.13 0dm, J ˆ
8.8, 2.4 Hz)
2.4 Hz)
153.2 Hz)
153.2 Hz)
6
7
7.41 0d, J ˆ 8.7 Hz)
6.82 0d, J ˆ 9.1 Hz)
8.22 0dd, J ˆ
8.7, 2.3 Hz)
8.10 0dd, J ˆ
9.1, 2.0 Hz)
8.82 0d, J ˆ
2.3 Hz)
80.78 0m, J ˆ 66.77 0dm, J ˆ
151.0 Hz) 151.0 Hz)
5.25 02H, broad s) 85.83 0m, J ˆ 65.45 0dm, J ˆ
150.0 Hz) 150.0 Hz)
8.57 0d, J ˆ
2.2 Hz)

290
A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
Table 4
13C NMR spectral data for compounds 2±7
Compound
Benzene carbons
C-1
Others
C-2
C-3
C-4
C-5
C-6
2
159.5 0d, J ˆ
271.5 Hz)
146.8
140.1 0d-qu, J ˆ 26.0, 20.0 Hz) 125.2 0m)
143.5 129.0 0d, J ˆ 119.3 0d, J ˆ
11.2 Hz)
143.5 126.5
26.0 Hz)
125.3
3a
3ba
151.2 0qu, J ˆ 18.8 Hz)
151.3 0qu, J ˆ 18.0 Hz)
124.8 0m, J ˆ 5.7 Hz)
16.6
147.7
125.0 0m, J ˆ 5.8 Hz)
126.0 0m, J ˆ 5.5 Hz)
140.1 127.1
134.5
125.1, 133.8,
140.0, 145.8
14.4, 66.4
4
5
6
7
148.4
157.5
146.7
146.9
141.4 0qu, J ˆ 20.0 Hz)
151.3 0qu, J ˆ 14.0 Hz)
154.5 0qu, J ˆ 18.5 Hz)
137.0 0qu, J ˆ 18.0 Hz)
139.8 128.3
114.2
128.3
136.5
118.7
125.3 0qu, J ˆ 5.2 Hz) 144.4 127.1
24.0, 26.1, 55.0
125.2
140.6 126.4
126.1 0qu, J ˆ 5.5 Hz) 137.1 127.6
a Spectrum was recorded in DMSO-d6.
doublet of doublets 0J1 ˆ 2:7 Hz, J2 ˆ 5:9 Hz) and can be
assigned to H-3. The couplings J1 and J2 were assigned as
meta-Ha±Hb and H±F couplings, respectively. The next
multiplet at d 8.47 ppm is the result of a hydrogen atom
coupling with two other hydrogen atoms and a ¯uorine atom
and can be attributed to H-5. Finally, the multiplet at d
7.47 ppm is a result of H-6 coupling with H-5 0ortho) and the
ring ¯uorine atom 0ortho). Additional evidence for structure
2 was obtained by IR, mass spectrometer 0MS) and high
resolution mass spectra 0HRMS).
carried out, even under more forcing conditions than those
used with 1-chloro-2-nitro-4-penta¯uorosulfanylbenzene
[52]. On the other hand, these reactions did allow us
to prepare a number of novel SF5-benzenes with ortho-
heteroatom bonded substituents 0see Scheme 2).
Compound 2 also reacts with the sodium salt of para-
nitrothiophenol as well as potassium ethyl xanthate in
boiling ethanol to give the asymmetric and symmetric
dinitrodiphenylsul®des 3b and 6, respectively. The synthetic
route to compound 6 is shown in Scheme 3 [53].
The ring ¯uorine atom in compound 2 is located ortho and
para with respect to the electron-withdrawing SF5 and NO2
groups, respectively. Normally, such a ¯uorine atom should
be susceptible to nucleophilic aromatic substitution. But
since this ¯uorine atom is ortho to such a bulky group,
nucleophilic substitution was expected to be more dif®cult,
especially when compared to similar reactions of 2,4-dini-
tro¯uorobenzene [51]. Only moderate yields 040±60%) of
the desired products were obtained when reactions of 2 were
Heating a mixture of compound 2 and concentrated
aqueous ammonia in a sealed ampule at 130±135 8C led
to substitution of the ¯uorine atom and the formation of the
amino derivative 7. The dinitrodiphenylsul®de 3b was oxi-
dized into the sulfone 011) using KMnO4 in boiling acetic
acid according to Scheme 4 [54].
All dinitro derivatives 3b, 7, and 11 were reduced to their
corresponding diamines 8, 9, and 12 with iron powder in the
presence of hydrochloric acid in ethanol. This method was
Table 5
IR, MS and HRMS data for compounds 2±7
Compound IR 0cmÀ1
)
MS m/z 0%)
HRMS
Calculated
266.979
Formula
Found
‡
‡
2
3125, 3097 0C±N), 1625, 1593,
1546, 1489, 1361 0N±O), 1263
0C±F), 908, 861, 833, 811 0S±F)
267 0M , 72), 248 0[M À F] , 27), 237
C6H3F6NO2S
266.980
‡
‡
0[M À NO] , 11), 221 0[M À NO2] , 27),
207 024), 205 025), 189 030), 149 058)
‡
‡
3a
3b
4
1583 0N±O), 900, 870, 850, 830 0S±F) 295 0M , 100), 276 0[M À F] , 9), 265
294.975
401.977
293.015
C7H6F5NO2S2
294.976
401.978
293.016
‡
0[M À NO] , 20), 245 07)
‡
‡
1517, 1457 0N±O), 856 0S±F)
402 0M , 100), 309 0[M À 2NO2 À H] , 5),
C12H7F5N2O4S2
‡
229 0[M À NO2 À SF5] , 5)
‡
‡
899, 859, 806 0S±F)
293 0M , 37), 265 0[M À C2H4] , 35),
C8H8F5N2O2S
‡
‡
245 0[M À C2H4 À HF] , 100),
229 0[M À OC2H5 À F] , 13), 208 05)
‡
‡
5
3123, 3091 0C±N), 1596 0N±O),
913, 894, 848, 815 0S±F)
332 0M , 46), 331 0[M À H] , 100),
332.062
C11H13F5N2O2S
332.064
‡
‡
291 0[M À C3H5] , 14), 285 018),
276 0[M À C4H8] , 23)
‡
‡
6
7
1606, 1584, 1534, 1513 0N±O),
908, 866, 844 0S±F)
528 0M , 100), 498 0[M À NO] , 12), 400
527.933
263.999
C12H6F10N2O4S3 527.932
C6H5F5N2O2S 263.998
‡
‡
0[M À SF5 À H] , 8), 355 0[M À NO2 À SF5] , 9)
‡
‡
3550, 3531, 3368 0NH), 1643,
1610, 1590 0N±O), 830 0S±F)
264 0M , 100), 244 0[M À HF] , 15),
‡
137 0[M À SF5] , 10)

A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
291
Scheme 2.
Scheme 3.

292
A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
FTS-40 FT-IR spectrometer; frequencies are reported in
cmÀ1. GC±MS analyses were carried out on a Hewlett-
Packard 5890 GC±MS 070 eV) using a 30 m capillary
column coated with HP1 stationary phase. HRMS were
recorded on a VG Autospec MS, and the uncertainty in
the mass measurements was Æ0.002 Da. Elemental analyses
were performed by Galbraith Laboratories Inc., in Knox-
ville, TN.
3.1. Preparation of aromatic disulfides 1a±e
Each starting aromatic disul®de 1a±e was obtained by a
two-step synthesis. The ®rst step was the transformation of
the corresponding aniline into the benzene sulfonyl chloride
by means of the Sandmeyer reaction [56,57], and the second
step was the reduction of the latter with an HBr solution in
glacial acetic acid in presence of phenol [58]. For example,
0.25 mol of the corresponding benzene sulfonyl chloride
was gradually dissolved in 1.25 l of glacial acetic acid
saturated with 125 g of gaseous HBr. Phenol 025.9 g,
0.275 mol) was added to the reaction mixture, which was
then heated carefully under stirring to 55±60 8C 0exothermic
reaction). After 24±36 h at this temperature, the reaction
mixture was cooled to room temperature and diluted with
water. The resulting precipitate was separated by ®ltration,
washed with water, dried in air, and recrystallized from
ethanol or acetic acid. The disul®des 1a±e were obtained in
80±90% yield as white or yellow-white ®ne crystals 0see
Tables 1 and 2).
Scheme 4.
also employed for the reduction of nitroaniline 7 and the
para-phenylenediamine 10. The reduction of the nitro group
of compound 2 by this same method gave a good yield of the
aniline 13. The amino group of the latter compound was
exchanged for a bromine atom according to the Sandmeyer
reaction. As a result, we have obtained a new bromo
derivative of ortho-¯uoro-SF5-benzene 14 that was not
available by the direct ¯uorination of disul®de 1e 0see
Scheme 5).
Structures of new products 3a, b and 4 have been con-
®rmed by NMR, IR, MS and HRMS 0see Tables 3±5). As
expected, substitution of the ring ¯uorine atom with some
other substituents lead to a disappearance of the additional
splitting of the resonances for the equatorial ¯uorines of SF5
group in the 19F NMR spectrum. The NMR chemical shift
data for compounds 2, 3a, b, and 4 are shown in Tables 3 and
4. The use of empirical additivity parameters [6,55] and the
extra coupling observed to the four equatorial ¯uorine atoms
of the SF5 group make the assignment of 13C NMR spectra
very straightforward.
3.2. Fluorination of aromatic disulfides
All reactions with AgF2 were performed in a stainless
steel reactor previously been passivated with elemental
¯uorine. While being passivated, the reactor contained six
copper sheets 010 mm  100 mm  0:2 mm) which would
later be used in the reactions. In a typical reaction, the
reactor was charged with 0.037 mol of disul®de, 1.0 mol of
AgF2, and the copper strips, with all manipulations being
carried out within a dry box. The vessel was then sealed,
evacuated on a vacuum line, cooled to 0 8C, and 90±100 ml
of CFC 113 was added by vacuum transfer. After warming to
room temperature, the vessel was held at 60 8C for 2 h and
then at 125±130 8C for 3 h, under intermittent shaking. The
reactor was then cooled to room temperature, and the reaction
mixture was extracted three times with 150 ml portions of
chloroform. The extract was ®ltered, washed with an aqueous
NaHCO3 solution, and dried over CaCl2. After removal of the
3. Experimental
Melting points were determined in open capillaries and
are uncorrected. Column chromatography was performed on
silica gel 60, 230±400 mesh 0Merck), with the solvents
indicated. TLC was run on silica gel 60 F254 plates 0Merck).
1H, 13C, and 19F NMR spectra were recorded on either a
Bruker AM 360 or 500 spectrometer, using TMS and CFCl3
as internal standards, respectively, and CDCl3 or acetone-d6
as solvent unless otherwise stated. Chemical shifts are
reported in ppm. Infrared spectra were recorded on a BioRad
Scheme 5.

A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
293
Table 6
Preparation of compounds 3±7
Compound Compound 2
Reagent
Solvent
Temperature
t 0h)
Eluent for
Yield
mp 08C)
08C)
chromatography
0%)
3a
3b
0.13 g 00.49 mmol)
3.45 g 012.9 mmol)
0.05 g 00.71 mmol) CH3SNa
EtOH, 5 ml
RT, reflux
5
2
Benzene:hexane, 1:1.5
45.3
46.0
106±107
0yellow solid)
148±150a 0from ethanol)
4 g 025.8 mmol)
EtOH, 30 ml Reflux
Benzene:ethylacetate, 4:1
4-nitrothiophenol 1.03 g
025.8 mmol), NaOH
0yellow solid)
4
5
6
0.13 g 00.49 mmol)
0.1 g 00.375 mmol)
3.2 g 012 mmol)
0.065 01 mmol) KOH
0.07 00.82 mmol) piperidine
2 g 012.5 mmol) KSC0ˆS)OEt
EtOH, 5 ml
EtOH, 3 ml
EtOH, 6 ml
RT, reflux
3
4
Benzene:hexane, 1:2
Benzene:hexane, 1:2
49.1
64.3
44.3
62±63 0white solid)
70±71 0orange solid)
225±227 0from ethanol)
0yellowish solid)
Reflux
Reflux
24
7
3 g 010.9 mmol)
l5 ml 28% NH4OH
130±135
5
Benzene
61.3
127±129 0yellow solid)
a Sample contains 40±45% of 4,40-bis-0nitrophenyl) disulfide.
chloroform, the resulting oil was analyzed by GC±MS, and
any SF5-containing product was separated by column chro-
matography 0silica, hexane:benzene 4:1).
in vacuum, and the remaining residue was washed with
water and extracted with benzene or chloroform. The
organic layer was dried over Na2SO4 and ®ltered. The
solvent was then evaporated, and the product was puri®ed
either by recrystallization or column chromatography.
3.2.1. 1-Fluoro-4-nitro-2-pentafluorosulfanylbenzene 82)
Compound 2 was prepared according to the general
procedure. Yield: 18.4% as a yellow oil, n2D2 ˆ 1:4565. Anal.
calcd. for C6H3F6NO2S: C, 26.97; H, 1.12; N, 5.24. Found:
C, 27.34; H, 1.10; N, 5.18.
3.4.1. 4,40-Diamino-2-pentafluorosulfanyldiphenyl
sulfide 88)
Compound 3b 01.21 g, 3.0 mmol) was reduced according
to the general method. The product was puri®ed by column
chromatography 0silica, benzene). Yield: 0.80 g 078%) as
yellowish solid, mp 76±77 8C. 1H NMR 0CDCl3) d 3.72 04H,
broad s), 6.55 01H, dd, J ˆ 8:6, 2.4 Hz), 6.63 02H, d,
J ˆ 8:6 Hz), 6.90 01H, d, J ˆ 8:6 Hz), 7.08 01H, d,
J ˆ 2:5 Hz), 7.23 02H, d, J ˆ 8:4 Hz); 19F NMR d 67.46
3.3. Nucleophilic substitution reactions of compound 2
1-Fluoro-4-nitro-2-penta¯uorosulfanylbenzene 02) was
dissolved in ethanol, and the nucleophilic reagent was added
under stirring 0see Table 6). After the reaction was complete,
the solvent was stripped from the reaction mixture under
vacuum, and the resulting residue was mixed with water and
extracted with benzene. The organic layer was dried over
Na2SO4 and ®ltered. The solvent was then evaporated,
and the product was puri®ed either on a column packed
with silica gel or by recrystallization from ethanol. The
characterization data for compounds 2±7 are shown in
Tables 3±5.
2
2
0m, JSF ÀSF ˆ 151:7 Hz), 86.91 0m, JSFÀSF ˆ 151:7 Hz);
4
4
13C NMR d 114.5 0qu, JCÀSF ˆ 5:0 Hz), 115.9, 118.4,
3
4
121.7, 124.6, 133.4, 135.8, 144.2, 147.1, 153.2 0qu,
2JCÀSF ˆ 18:0 Hz). IR 0Nujol) 3418, 3312, 3208 0N±H),
4
850 0S±F) cmÀ1. GC±MS m/z 0relative intensity) 342 0M ,
‡
‡
‡
100), 214 0[M À SF5 À H] , 42), 199 0[M À SF5 À NH2] ,
‡
‡
30), 171 0M /2, 17), 124 0C6H6NS , 42). HRMS calcd. for
C12H11F5N2S2 342.028. Found: 342.028. Anal. calcd. for
C12H11F5N2S2: C, 42.10; H, 3.24; N, 8.18. Found: C, 42.34;
H, 3.23; N, 7.97.
3.3.1. 1-Ethoxy-4-nitro-2-pentafluorosulfanylbenzene 84)
Anal. calcd. for C8H8F5NO2S: C, 32.77; H, 2.75; N, 4.78.
Found: C, 34.35; H, 3.05; N, 4.63.
3.4.2. Bis-84-amino-2-pentafluorosulfanylphenyl)
sulfide 89)
3.3.2. 40-Nitro-20-pentafluorosulfanyl-1-
phenylpiperidine 85)
Anal. calcd. for C11H13F5N2O2S: C, 39.76; H, 3.94; N,
8.43. Found: C, 40.69; H, 4.32; N, 8.39.
Dinitro compound 6 01.37 g, 2.6 mmol) was converted
into the diamino derivative 9 by the general method. The
product was separated by column chromatography 0silica,
benzene). Yield: 1.04 g 085%) as white-yellow solid, mp
1
169±170 8C. H NMR 0CDCl3) d 4.76 02H, broad s), 6.62
3.4. Reduction of nitro compounds 2, 3b, 6, 7, 11
01H, dd, J ˆ 8:5, 2.4 Hz), 6.99 01H, d, J ˆ 8:5 Hz), 7.12
01H, d, J ˆ 2:4 Hz); 19F NMR
d
67.78 0m,
ˆ 151:8 Hz); 13C
2
2
Iron powder 04±5 mmol per mmol of NO2 groups) was
added in portions to a re¯uxing solution of the correspond-
ing nitro compound in 5 ml of ethanol and 0.2 ml of con-
centrated hydrochloric acid, under stirring. After re¯uxing
for 2±3 h, the mixture was decolorized with activated char-
coal, ®ltered, cooled to room temperature, and made slightly
basic by the addition of NH4OH. The solvent was evaporated
J
ˆ 151:8 Hz) 86.23 0m, J
SF4ÀSF
SFÀSF4
NMR d 112.0, 114.6, 118.6, 136.8, 145.6, 155.2 0C-2, qu,
2JCÀSF ˆ 14:6 Hz). IR 0Nujol) 3473, 3344 0N±H), 911, 849,
4
803 0S±F) cmÀ1. MS m/z 0relative intensity) 468 0M , 100),
‡
‡
‡
‡
360 0[M À SF4] , 5), 340 0[M À SF5 À H] , 9), 232
‡
0[M À SF5 À SF4 À H] , 9), 214 0[M À 2SF5] , 48), 186
‡
0C12H10S , 13). HRMS calcd. for C12H10F10N2S3 467.985.

294
A.M. Sipyagin et al. / Journal of Fluorine Chemistry 112 82001) 287±295
Found: 467.983. Anal. calcd. for C12H10F10N2S3: C, 30.77;
H, 2.15; N, 5.98. Found: C, 30.84; H, 2.25; N, 5.95.
115.8, 126.1, 129.0, 130.1, 136.6, 153.37 0C-2, qu,
3JCÀSF ˆ 18:0 Hz), 153.45, 153.5. IR 0Nujol) 3505, 3479,
4
3378 0N±H), 862 0S±F) cmÀ1. GC±MS m/z 0relative inten-
‡
‡
3.4.3. 2-Pentafluorosulfanyl-1,4-phenylenediamine 810)
Compound 7 01.0 g, 3.8 mmol) was reduced with iron
powder by the general method. The product was puri®ed by
recrystallization from hexane. Yield: 0.67 g 075%) as ivory
sity) 374 0M , 100), 281 0[M À C6H5NH2] , 40), 207 090),
‡ ‡
191 012), 156 0C6H6NO2S , 84), 140 0C6H4O2S , 23).
HRMS calcd. for C12H11F5N2O2S2 374.018. Found:
374.016. Anal. calcd. for C12H11F5N2O2S2: C, 38.50; H,
2.96; N, 7.48. Found: C, 38.92; H, 3.08; N, 7.38.
1
colored solid, mp 106±108 8C. H NMR 0CDCl3) d 3.35
02H, broad s), 4.04 02H, broad s), 6.62 01H, d, J ˆ 8:63 Hz),
6.69 01H, dd, J ˆ 8:5, 2.3 Hz), 6.95 01H, d, J ˆ 2:5 Hz); 19
F
3.4.6. 4-Fluoro-3-pentafluorosulfanylaniline 813)
2
NMR d 65.62 0m, JSF ÀSF ˆ 148:5 Hz), 88.93 0m,
Compound 2 05.6 g, 21 mmol) was transformed into the
amino derivative by the standard method. For puri®cation,
compound 13 was passed through a column 0silica, ben-
4
2JSFÀSF ˆ 148:5 Hz); 13C NMR
d 114.1 0C-3, qu,
4
3JCÀSF ˆ 5:5 Hz), 120.6, 121.2, 134.0, 137.1, 140.4 0C-2,
4
qu, 2JCÀSF ˆ 14:6 Hz). IR 0Nujol) 3470, 3422, 3318, 3208
zene). Yield: 3.9 g 078%) as yellow oil, n2D2 ˆ 1:4710. H
1
4
0N±H), 824 0S±F) cmÀ1. GC±MS m/z 0relative intensity) 234
NMR 0CDCl3) d 3.60 02H, broad s), 6.76 01H, m), 6.96±6.99
‡
‡
4
0M ,
100),
125
0[M À SF4 À H] ,
9),
106
02H, m); 19F NMR d À123.27 0qu-m, JSFÀSF ˆ 24:9 Hz),
4
‡
2
4
0[M À SF5 À H] , 57). HRMS calcd. for C6H7F5N2S
234.025. Found: 234.023. Anal. calcd. for C6H7F5N2S: C,
30.77; H, 3.01; N, 11.96. Found: C, 31.15; H, 3.39; N, 11.55.
67.37 0m, JSF ÀSF ˆ 151:2 Hz, JCFÀSF ˆ 24:9 Hz), 81.82
4
4
0m, JSFÀSF ˆ 151:2 Hz, JSFÀCF ˆ 1:7 Hz); 13C NMR d
2
4
4
113.6 0C-2, qu, J ˆ 4:8 Hz), 118.2 0C-5, d, J ˆ 25:0 Hz),
119.7 0C-6, d, J ˆ 7:8 Hz), 140.0 0C-3, d-qu), 142.3 0C-1, s),
3.4.4. 4,40-Dinitro-2-pentafluorosulfanyldiphenyl
sulfone 811)
149.0 0C-4, d, JCÀF ˆ 250:2 Hz). IR 0®lm) 3482, 3400
1
0N±H), 3228, 865, 818 0S±F) cmÀ1. GC±MS m/z 0relative
‡
‡
Potassium permanganate 01.85 g) in 12 ml of hot water
was added dropwise with stirring to 1.6 g 04.0 mmol) of
compound 3b dissolved in boiling acetic acid 030 ml). When
the addition was complete, water 030 ml) was added, and the
cooled mixture was decolorized with SO2. The precipitate
was separated by ®ltration and puri®ed by column chroma-
tography 0silica, benzene:ethylacetate 4:1). Yield: 1.04 g
060%) as a yellowish solid, mp 164±166 8C. 1H NMR
0acetone-d6) d 8.21 02H, d, J ˆ 8:9 Hz), 8.66 02H, d,
J ˆ 8:9 Hz), 8.83 01H, dd, J ˆ 8:8, 2.1 Hz), 8.88 01H, d,
J ˆ 2:1 Hz), 9.08 01H, d, J ˆ 8:8 Hz); 19F NMR d 71.40 0m,
intensity) 237 0M , 100), 129 0[M À SF4] , 27), 110
‡
0[M À SF5] , 50), 83 057). HRMS calcd. for C6H5F6NS
237.005. Found: 237.003.
3.5. 1-Bromo-4-fluoro-3-pentafluorosulfanylbenzene 814)
Compound 13 03.2 g, 12 mmol), dissolved in 100 ml of
48% HBr, was diazotized at 0±5 8C with 1.02 g of NaNO2
dissolved in 2.5 ml H2O. The resulting solution was gradu-
ally added to a boiling mixture of 10 ml HBr 048%) and 2 g
of CuBr in a vessel with a steam inlet. After steam distilla-
tion, the liquid product was separated with a funnel, dried,
and then puri®ed by column chromatography 0silica, hex-
ane). Yield of colorless liquid: 1.6 g 044%), n2D2 ˆ 1:4680.
1H NMR 0CDCl3) d 7.12 01H, m), 7.63 01H, m), 7.88
2
2JSF ÀSF ˆ 150:8 Hz), 79.24 0m, JSFÀSF ˆ 150:8 Hz); 13C
4
4
3
NMR d 125.6, 126.6 0qu, JCÀSF ˆ 6:7 Hz), 128.9, 130.2,
4
137.6, 142.5, 146.6, 151.5, 151.9, 152.4 0C-2, qu,
2JCÀSF ˆ 22:2 Hz). IR 0Nujol) 3120 0C±H), 1613, 1542
4
0N±O), 870 0S±F) cmÀ1. GC±MS m/z 0relative intensity)
01H, dd, J ˆ 6:0, 2.5 Hz); 19F NMR
d
À109.09
‡
‡
‡
4
2
434 0M , 2), 415 0[M À F] , 2.5), 308 0[M À SF5 ‡ H] ,
0qu, JCFÀSF ˆ 26:0 Hz), 68.92 0m, JSF ÀSF ˆ 151:6 Hz,
4
4
‡
‡
2.5), 296 0C6H3F5NO3S2 , 84), 229 0C12H7F5NO2S , 10),
4JSF ÀCF ˆ 26:0 Hz), 80.81 0m, 2JSFÀSF ˆ 151:6 Hz,
4
4
‡
‡
207 07), 186 0C6H4NO4S , 85), 122 0C6H4NO2 , 100).
HRMS calcd. for C12H7F5N2O6S2 433.967. Found:
433.969. Anal. calcd. for C12H7F5N2O6S2: C, 33.19; H,
1.62; N, 6.45. Found: C, 33.40; H, 1.72; N, 6.38.
4JSFÀCF ˆ 2:1 Hz); 13C NMR d 116.2 0C-1, s), 119.6
0C-5, d, J ˆ 25:2 Hz), 131.4 0C-2, qu, J ˆ 4:4 Hz), 136.7
0C-6, d, J ˆ 8:7 Hz), 140.9 0C-3, d-qu), 155.1 0C-4, d,
1JCÀF ˆ 261:4 Hz). IR 0®lm) 3108 0C±H), 863 0S±F), 813
0S±F) cmÀ1. GC±MS m/z 0relative intensity) 302/300 0M ,
‡
‡
‡
3.4.5. 4,40-Diamino-2-pentafluorosulfanyldiphenyl
sulfone 812)
100), 283/281 0[M À F] , 10), 194/192 0[M À SF4] , 60),
‡ ‡
113 0C6H3F2 , 50), 94 0C6H3F , 50). HRMS calcd. for
C6H381BrF6S and C6H379BrF6S 301.902 and 299.904.
Found: 301.902 and 299.904.
The dinitro compound 11 01.3 g, 3.0 mmol) was reduced
according to the general procedure. The product was puri®ed
by recrystallization from toluene. Yield: 0.90 g 080%) as
white-yellow solid, mp 191±193 8C. 1H NMR 0acetone-d6) d
5.53 02H, broad s), 6.03 02H, broad s), 6.70 02H, d,
J ˆ 8:7 Hz), 6.97 01H, dd, J ˆ 8:9, 2.2 Hz), 7.33 01H, d,
J ˆ 2:2 Hz), 7.43 02H, d, J ˆ 8:7 Hz), 8.26 01H, d,
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2
4
2
83.90 0m, JSFÀSF ˆ 150:0 Hz); 13C NMR d 113.8, 115.4,
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