A novel and efficient cross-coupling of tris(fluorinated phenyl)boroxins with disulfides catalyzed by CuI/1,10-phenanthroline

Article abstract of DOI:10.1139/V10-025

Under an oxygen atmosphere, the cross-coupling of tris(fluorinated phenyl)boroxins and disulfides catalyzed by CuI/1,10-phenanthroline were smoothly achieved to produce the corresponding asymmetric fluorinated arylsulfides in good-to-excellent yields.

Full text of DOI:10.1139/V10-025

485
A novel and efficient cross-coupling of
tris(fluorinated phenyl)boroxins with disulfides
catalyzed by CuI/1,10-phenanthroline
Chuanming Yu, Beibei Jin, Zhenyu Liu, and Weihui Zhong
Abstract: Under an oxygen atmosphere, the cross-coupling of tris(fluorinated phenyl)boroxins and disulfides catalyzed by
CuI/1,10-phenanthroline were smoothly achieved to produce the corresponding asymmetric fluorinated arylsulfides in
good-to-excellent yields.
Key words: disulfide, tris(fluorinated phenyl)boroxin, fluorinated arylsulfide, cross-coupling, cuprous iodide.
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Resume : On a effectue sans difficulte le couplage croise de tris(flurophenyl)boroxines et de disulfures, sous atmosphere
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d’oxygene et catalyse par du CuI/phenanthroline; on a pu isoler les arylsulfures fluores asymetriques correspondants avec
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des rendements allant de bons a excellents.
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Mots-cles : disulfure, tris(flurophenyl)boroxine, arylsulfure fluore, couplage croise, iodure cuivreux.
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[Traduit par la Redaction]
Introduction
Scheme 1.
Transition-metal-catalyzed aryl carbon–sulfur formation
reaction is an indispensable tool in synthetic organic chem-
istry. Aryl sulfides and their derivatives are a common func-
tional group in numerous pharmaceutical and biological
active compounds.1 However, compared with metal-catalyzed
formation of aryl C–N or aryl C–O bonds, transition-metal-
mediated carbon–sulfur bonds formation have not received
particular interest, which brought about a further research
area.2 In the 1980s, Migita and co-workers3 first reported
C–S bond formation through Pd(PPh3)4 catalyzing the cou-
pling reaction of aryl halides with thiols, but this method re-
quired considerable environmentally unfriendly PPh3 as
ligands. Later, various metal catalysts such as palladium,4
nickel,5 cobalt6 and copper7 have been developed among
these reactions. While some synthetic difficulties must be
addressed, for example, high temperatures, high catalyst
loadings, and specially designed phosphine ligands,8 it is
gratifying to see that aryl triflates and organoboronic acids
are sometimes used as good counterparts instead of aryl hal-
ides to overcome the disadvantages of the traditional reac-
tions.9 To the best of our knowledge, the preparation of
asymmetric fluorinated arylsulfides via the cross-coupling
of disulfide with tris(fluorinated phenyl)boroxin has not
been reported.10
mation without aryl halides should be desirable from the
viewpoint of atom economy and the waste treatment of hy-
drogen halides.12 Herein, we wish to report an efficient
cross-coupling of tris(fluorinated phenyl)boroxins with disul-
fides catalyzed by the CuI/1,10-phenanthroline complex
under oxygen atmosphere to give the corresponding fluori-
nated arylsulfides in good to excellent yields (Scheme 1).
Results and discussion
Initially, the cross-coupling reaction of tris(3-fluorophe-
nyl)boroxin (1a) with 1,2-di-p-tolyldisulfide (2a) was inves-
tigated under different conditions. Various factors including
copper source and its amount, solvents, ligands, and reaction
temperatures were screened. Firstly, this cross-coupling re-
action was carried out in a mixture of DMSO and water
(2:1) at 100 8C catalyzed by CuI in the presence of 2,2-bi-
pyridyl,10 the desired product (3-fluorophenyl)-4-tolylsulfide
(3a) was obtained in only 26% yields (Table 1, entry 1) and
most of 2a was recovered. When we carried out the same
reaction in an oxygen atmosphere, the yield of correspond-
ing target product 3a improved up to 68% (Table 1, entry 2),
The arylation of tris(fluorinated phenyl)boroxins is of cur-
rent interest because the unique properties conferred by the
fluorine atoms might get some unexpected results and high
biological activity compounds that are otherwise difficult to
obtain.11 Moreover, the analogous carbon–sulfur bond for-
Received 25 August 2009. Accepted 1 December 2009. Published on the NRC Research Press Web site at canjchem.nrc.ca on 15 April
2010.
C. Yu,1 B. Jin, Z. Liu, and W. Zhong. Key Laboratory of Pharmaceutical Engineering of Ministry of Education, College of
Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P.R. China.
1Corresponding author (e-mail: pharmlab@zjut.edu.cn).
Can. J. Chem. 88: 485–491 (2010)
doi:10.1139/V10-025
Published by NRC Research Press

486
Can. J. Chem. Vol. 88, 2010
Table 1. Copper-catalyzed coupling of tris(3-fluorophenyl)boroxin with 1,2-di-p-tolyldisulfide.
Entry
1b
2
[Cu]
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
—
Ligand
L1
L1
L1
—
Solvent and ratios
DMSO/H2O (2:1)
DMSO/H2O (2:1)
DMSO/H2O (2:1)
DMSO/H2O (2:1)
DMSO/H2O (2:1)
DMSO/H2O (2:1)
DMSO/H2O (2:1)
DMSO/H2O (1:1)
DMSO
DMSO/H2O (1:2)
1,4-Dioxane
DMF
2-Methyltetrahydrofuran
DMSO/H2O (1:1)
DMSO/H2O (1:1)
DMSO/H2O (1:1)
DMSO/H2O (1:1)
DMSO/H2O (1:1)
Time (h)
T (8C)
100
100
90
120
90
90
90
90
90
90
90
90
90
90
90
90
90
Yield (%)a
26
68
ND
ND
93
Trace
ND
94
93
88
56
68
54
ND
Trace
Trace
Trace
Trace
12
12
12
24
8
8
8
8
8
8
8
8
8
8
8
8
8
3c
4
5
6
7
8
L2
L3
L4
L2
L2
L2
L2
L2
L2
L2
L2
L2
L2
9
10
11
12
13
14
15
16
17
18
CuBr
CuCl
CuCl2
Cu(OAc)2 L2
8
90
Note: Conditions: 1a (1.5 mmol), 2a (0.5 mmol), [Cu] (0.025 mmol), ligand (0.025 mmol) at 90 8C under oxygen atmosphere.
ND = not determined.
aIsolated yields based on 2a.
bUnder air atmosphere.
cUnder nitrogen atmosphere.
while no desired product was observed under nitrogen at-
mosphere (Table 1, entry 3). Secondly, the effect of ligands
was investigated (Fig. 1). The coupling reaction did not pro-
ceed in the absence of ligand (Table 1, entry 4), even by
prolonging the reaction time or increasing the temperature.
To our delight, the yield of product 3a increased up to 94%
when 1,10-phenanthroline (L2) was employed as ligand
(Table 1, entries 5–7). Then, 1,10-phenanthroline (L2) was
employed under Taniguchi’s10 conditions, and the reactions
showed that this ligand was less stable than 2,2-bipridyl
(L1). Subsequently, we studied the effect of solvents, which
have a negligible impact as compared to the reactions with-
out additional water (Table 1, entries 5 and 8–9). A rate of
DMSO and water of 1:1 was found not only to be an appro-
priate solvent for this reaction but also friendly to environ-
ment (Table 1, entries 5 and 8–13). Among these copper
sources, CuI was the most effective (Table 1, entries 5 and
14–18). Therefore, the optimal conditions for the synthesis
of fluorinated arylsulfides is by the treatment of disulfides
and tri(fluorinated phenyl)boroxins in DMSO/H2O (1:1),
under oxygen atmosphere at 90 8C, in the presence of only
5 mol% of CuI/L2 (1,10-phenanthroline).
Fig. 1. Ligands employed for the C–S coupling reaction.
well under the optimal reactions (Table 2, entries 1–9). The
present process was shown to work well in the coupling of
tris(fluorinated phenyl)boroxins with disulfides containing
free para-hydroxyl or meta-amino groups to provide the de-
sired products 3j, 4j and 3k, 4k in good yields (Table 2, en-
tries 10 and 11). These compounds are very important
intermediates.
Unfortunately, as shown in Table 2, no expected product
was detected when using benzothiazol-2-yl disulfide (2l) as
substrate (Table 2, entry 12). The same result happened
with 2m (Table 2, entry 13). The possible reason was that
the benzothiazol-2-yl group and carboxyl group had strong
electron-donating effects and decreased the reactivities of
corresponding disulfides.
Another interesting aspect of the reaction was when ali-
phatic of disulfides as substrates were employed (Table 2,
entry 14). While 1,2-dibenzyldisulfide (2n) was found to
give the corresponding products 3n and 4n only in yields of
23% and 29%, respectively, the main products were bis(4-
fluorophenyl)sulfide (5a) and bis(3,4,5-trifluorophenyl)sul-
With the optimal conditions in hand, we decided to assess
the scope of this reaction. Tris(fluorinated phenyl)boroxins
were first investigated to react with a series of disulfides
(see Table 2). It was found that both electron-donating and
electron-withdrawing substituted disulfides were tolerated
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Yu et al.
487
Table 2. CuI/1,10-phenanthroline-catalyzed coupling of tris(fluorinated phenyl)boroxins with
disulfides.
Entry
1
R
Ar
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
Time (h)
8
7
7
6.5
7
Product
3a
4a
3b
4b
3c
Yield (%)a
90
95
99
99
99
4-CH3C6H4
2
4-BrC6H4
3
4-ClC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
6.5
7
6.5
7
6.5
7
4c
99
93
95
97
99
99
4
4-FC6H4
3d
4d
3e
4e
3f
5
4-O2NC6H4
C6H5
6
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
3,4,5-F3C6H2
3-FC6H4
6.5
8
7
8
7
7
6.5
8
7
8
4f
99
90
93
93
93
94
95
75
79
67
73
ND
ND
ND
58
28
29
7
2,4-(CH3)2C6H3
4-Isopropyl-C6H4
2,3-(Cl)2C6H3
4-OHC6H4
2-NH2C6H4
Benzothiazol-2-yl
HO2CCH2CH2
Bn
3g
4g
3h
4h
3i
4i
3j
4j
8
9
10
11
12
13
14
3k
4k
3l
7
24
24
24
24
24
24
4l
3m
4m
3n
4n
3,4,5-F3C6H2
Note: Conditions: 1 (1.5 mmol), 2 (0.5 mmol), CuI/L2 (0.025 mmol/0.025 mmol), DMSO/H2O (20 mL),
O2 (1.01 Â 105 Pa). ND = not determined.
aIsolated yields based on disulfides.
Scheme 2.
Fig. 2. Plausible mechanism to produce 5 from PhCH2SAr.
fide (5b) in satisfactory yields (Scheme 2). The mechanistic
speculation was shown in Fig. 2; presumably, 1,2-dibenzyl-
disulfide underwent the expected cross-coupling reaction to
form the alkylarylsulfides, followed by subsequent Cu-
promoted S-dealkylation to generate arylthiols or radicals in
situ and then were oxidated disulfides (6), which partici-
pated in a second cross-coupling with another tris(fluori-
nated phenyl)boroxins to afford diarylsulfides (5).13
oxins in the same conditions. In this way, we demonstrate
that only 1,2-dibenzyldisulfuide can be used as a surrogate
for sulfides in symmetrical diarylation reactions.
Nevertheless, tris(pentafluorophenyl)boroxin seems to be
sensitive to the series of reaction conditions in Table 1. The
Only desired products 3a and 4a were observed after
treating model disulfide 2a with tris(fluorinated phenyl)bor-
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488
Can. J. Chem. Vol. 88, 2010
Scheme 3.
NMR, and HR-MS. Data of known compounds have been
found to be identical to those reported.
(3-Fluorophenyl)-4-tolylsulfide (3a)
Colorless viscous oil. IR (KBr, cm–1): 3072, 2917, 1599,
1
1492, 881, 810, 774. H NMR (400 MHz, CDCl3) d: 2.33
(s, 3H), 6.77–6.85 (m, 2H), 6.95 (d, J = 7.6 Hz, 1H), 7.13
(d, J = 5.2 Hz, 3H), 7.34 (d, J = 8.0 Hz, 2H). 13C NMR
(100 MHz, CDCl3) d: 21.0 (d, J = 15.7 Hz, 1C), 112.7 (d, J =
21.2 Hz, 1C), 115.2 (d, J = 23.2 Hz, 1C), 123.9, 128.4,
129.3, 129.7, 130.0–130.3 (m, 1C), 130.5, 133.5, 138.6,
140.5 (d, J = 7.5 Hz, 1C), 163.0 (d, J = 246.6 Hz, 1C). 19F
NMR (376 MHz, CDCl3) d: –132.72 (dd, J = 15.4, 9.4 Hz,
1F). MS (EI) m/z (%): 218 (M+, 100), 203 (5). HR-MS
calcd. for C13H11FS [M+]: 218.0565; found: 218.0553.
reasonable explanation was that the basic catalyst system, or
even the light basic solvent DMSO at 90 8C, may be decom-
posing tris(pentafluorophenyl)-boroxin (Scheme 3).14
Conclusion
(4-Bromophenyl)-3-fluorophenylsulfide (3b)
1
Colorless viscous oil. Lit. value16a bp 360.9 8C. H NMR
In summary, we have developed a practical protocol to
asymmetric fluorinated arylsulfides via CuI catalyzed cross-
coupling of tris(fluorinated phenyl)boroxins with disulfides
in the presence of 1,10-phenanthroline under an oxygen at-
mosphere. The merits of our method are simple operation,
short reaction times, good to excellent yields, and one-pot
synthesis of asymmetric fluorinated phenylsulfides. Further
studies on the application of fluorinated boronic acids are
now in progress in our laboratory.
(400 MHz, CDCl3) d: 6.89–6.97 (m, 2H), 7.05 (d, J =
7.6 Hz, 1H), 7.24 (dd, J = 15.2, 8.4 Hz, 3H), 7.45 (d, J =
8.8 Hz, 2H). 19F NMR (376 MHz, CDCl3) d: –110.83 (dd, J =
3.0, 2.0 Hz, 1F).
(4-Chlorophenyl)-3-fluorophenylsulfide (3c)
Colorless viscous oil. IR (KBr, cm–1): 3064, 2925, 2839,
1598, 1580, 1474, 881, 821, 776. 1H NMR (400 MHz,
CDCl3) d: 6.88–6.95 (m, 2H), 7.03 (d, J = 7.6 Hz, 1H),
7.23 (dd, J = 15.2, 7.2 Hz, 1H), 7.27–733 (m, 4H). 13C
NMR (100 MHz, CDCl3) d: 114.2 (d, J = 20.5 Hz, 1C),
117.0 (d, J = 22.6 Hz, 1C), 125.7, 130.0, 130.7 (d, J =
9.0 Hz, 2C), 133.0, 133.8 (2C), 134.4, 138.8 (d, J = 7.2 Hz,
1C), 163.3 (d, J = 247.3 Hz, 1C). 19F NMR (376 MHz,
CDCl3) d: –110.95 ~ –111.01 (m, 1F). MS (EI) m/z (%):
238 (M+, 100), 203 (45). HR-MS calcd. for C12H8ClFS
[M+]: 238.0019; found: 238.0004.
Experimental section
General method
All reagents are commercially available. Tris(4-fluorophe-
nyl)boroxin, tris(3,4,5-trifluorophenyl)boroxin, and tris(pen-
tafluorophenyl)boroxin were prepared from our own
laboratory.15 Melting points were measured on a digital
1
melting-point apparatus WR-1B and were uncorrected. H
NMR, 19F NMR, and 13C NMR spectra were recorded on a
Varian 400 MHz instrument using CDCl3 as the solvent, and
chemical shifts were expressed in parts per million (ppm)
using TMS and trifluoroacetic acid as internal standards.
Mass spectra were measured with a Trace Finnigan DSQ.
High resolution mass spectra (HR-MS) analyse were meas-
ured on an Agilent 6210 TOF LC/MS using APCI (electro-
spray ionization) techniques. IR measurements were carried
out with a Nicolet Aviatar-370 instrument. Elemental analy-
sis was performed on a VarioEL-III instrument. All spectral
data of the products were identical to authentic samples.
(3-Fluorophenyl)-4-fluorophenylsulfide (3d)
Yellow oil. Lit. value16b bp 313.7 8C. 1H NMR
(400 MHz, CDCl3) d: 6.94 (td, J = 9.6, 2.0 Hz, 2H), 7.05
(d, J = 7.6 Hz, 1H), 7.25 (d, J = 8.0 Hz, 3H), 7.45 (d, J =
8.8 Hz, 2H). 19F NMR (376 MHz, CDCl3) d: –110.90 (dd, J =
15.1, 9.0 Hz, 2F).
(3-Fluorophenyl)-4-nitrophenylsulfide (3e)
Yellow solid. Mp (recrystallization in petroleum ether)
71.5–73.5 8C (lit. value16c mp 71.0 8C). 71 8C. H NMR
1
(400 MHz, CDCl3) d: 7.13–7.14 (m, 1H), 7.21–7.27 (m,
3H), 7.30 (d, J = 7.6 Hz, 1H), 7.41 (dd, J = 7.6, 5.6 Hz,
1H), 8.11 (d, J = 8.8 Hz, 2H). 19F NMR (376 MHz, CDCl3)
d: –110.63 ~ –110.69 (m, 1F).
General procedure for the preparation of asymmetric
fluorinated arylsulfides
To a solution of CuI (0.025 mmol) and 1,10-phenanthro-
line (L2, 0.025 mmol) in DMSO/H2O (1:1, 20 mL) were
added disulfides (0.5 mmol) and tri(3-fluorophenyl)boroxin
(1.5 mmol). The mixture was stirred at 90 8C under O2 at-
mosphere for a given time. Then the reaction was quenched
with brine and extracted with ethyl acetate (3 Â 15 mL).
The combined organic phase was dried over anhydrous
Na2SO4 and concentrated in vacuo and the crude product
was purified by column chromatography on silica gel with
petroleum ether as eluent to afford the desired product. All
(3-Fluorophenyl)phenylsulfide (3f)
1
Colorless viscous oil. Lit. value16c bp 302.2 8C. H NMR
(400 MHz, CDCl3) d: 6.86 (td, J = 8.4, 2.4 Hz, 2H), 7.03 (d,
J = 7.6 Hz, 1H), 7.20 (dd, J = 14.0, 8.0 Hz, 1H), 7.32 (dd, J =
15.6, 7.6 Hz, 3H), 7.41 (d, J = 7.2 Hz, 2H). 19F NMR
(376 MHz, CDCl3) d: –111.51 (dd, J = 15.4, 9.4 Hz, 1F).
(3-Fluorophenyl)-2,4-dimethylphenylsulfide (3g)
Colorless viscous oil. IR (KBr, cm–1): 3056, 2917, 1598,
1
1472, 880, 815, 773. H NMR (400 MHz, CDCl3) d: 2.33
1
new compounds were identified by H NMR, 13C NMR, 19F
(s, 6H), 6.68 (dt, J = 6.0, 2.0 Hz, 1H), 6.78 (td, J = 8.4,
Published by NRC Research Press

Yu et al.
489
1.6 Hz, 1H), 6.85 (d, J = 8.0 Hz, 1H), 7.03 (d, J = 3.6 Hz,
1H), 7.15 (dd, J = 14.0, 8.0 Hz, 2H), 7.37 (d, J = 8.0 Hz,
1H). 13C NMR (100 MHz, CDCl3) d: 20.5, 21.1, 112.2 (d, J =
21.3 Hz, 1C), 114.0 (d, J = 23.5 Hz, 1C), 122.8, 127.7,
127.8, 130.7 (d, J = 8.4 Hz, 1C), 131.8, 135.6, 139.6, 140.7
(d, J = 7.6 Hz, 1C), 141.7, 163.1 (d, J = 246.6 Hz, 1C). 19F
NMR (376 MHz, CDCl3) d: –132.07 (dd, J = 24.9, 9.4 Hz,
1F). MS (EI) m/z (%): 127 (100), 137 (35), 232 (M+, 5).
HR-MS calcd. for C14H13FS [M+]: 232.0732; found:
232.0722.
MS (EI) m/z (%): 219 (M+, 100), 186 (25). HR-MS calcd.
for C12H10FNS [M+]: 219.0518; found: 219.0505.
(3-Fluorophenyl)benzylsulfide (3n)
White soild. Mp (recrystallization in petroleum ether)
30.5–31.4 8C. IR (KBr, cm–1): 3060, 2921, 1599, 1495, 773,
1
713, 697, 678. H NMR (400 MHz, CDCl3) d: 4.13 (s, 2H),
6.86 (td, J = 8.4, 2.4 Hz, 1H), 7.03 (dd, J = 22.0, 7.6 Hz,
2H), 7.31–7.18 (m, 6H). 13C NMR (100 MHz, CDCl3) d:
38.5, 110.4, 113.1 (t, J = 6.8 Hz, 2C), 115.7–116.0 (m, 1C),
118.8, 124.6 (2C), 127.4–128.8 (m, 2C), 130.0 (d, J =
8.4 Hz, 1C), 136.7, 161.5–164.0 (m, 1C). 19F NMR
(376 MHz, CDCl3) d: –111.65 ~ –111.73 (m, 1F). MS (EI)
m/z (%): 218 (M+, 100), 91 (75). HR-MS calcd. for
C13H11FS [M+]: 218.0565; found: 218.0554.
(3-Fluorophenyl)-4-isopropylphenylsulfide (3h)
Colorless viscous oil. IR (KBr, cm–1): 2962, 1598, 1473,
1
1426, 881, 828, 775, 678, 547. H NMR (400 MHz, CDCl3)
d: 1.24 (d, J = 6.8 Hz, 6H), 2.88 (dd, J = 13.6, 7.2 Hz, 1H),
6.80 (dd, J = 8.4, 8.4 Hz, 1H), 6.88 (d, J = 9.6 Hz, 1H),
6.97–7.04 (m, 1H), 7.12–7.21 (m, 3H), 7.37 (d, J = 8.4 Hz,
2H). 13C NMR (100 MHz, CDCl3) d: 23.8 (2C), 33.8 (d, J =
11.4 Hz, 1C), 112.8 (d, J = 21.2 Hz, 1C), 115.4 (d, J =
22.8 Hz, 1C), 116.8, 122.7, 124.1 (2C), 127.2–128.1 (m,
1C), 129.7–130.4 (m, 1C), 133.4, 135.5 (d, J = 7.6 Hz, 1C),
149.4, 163.0 (d, J = 246.5 Hz, 1C). 19F NMR (376 MHz,
CDCl3) d: –111.32 ~ –111.36 (m, 1F). MS (EI) m/z (%):
246 (M+, 95), 231 (100). HR-MS calcd. for C15H15FS [M+]:
246.0878; found: 246.0843.
(3,4,5-Trifluorophenyl)-4-tolylsulfide (4a)
Colorless viscous oil. IR (KBr, cm–1): 2925, 1599, 1515,
1
1425, 1046, 878, 829, 760. H NMR (400 MHz, CDCl3) d:
2.37 (s, 3H), 6.74 (dd, J = 8.0, 6.8 Hz, 2H), 7.20 (d, J =
8.0 Hz, 2H), 7.35 (d, J = 8.0 Hz, 2H). 13C NMR (100 MHz,
CDCl3) d: 21.2, 112.0 (dd, J = 16.7, 6.1 Hz, 2C), 128.3,
130.6 (2C), 134.0 (2C), 136.7, 139.5, 151.2 (d, J =
150.2 Hz, 2C). 19F NMR (376 MHz, CDCl3) d: –162.66 ~
–162.80 (m, 1F), –132.87 ~ –132.98 (m, 2F). MS (EI) m/z
(%): 254 (M+, 100), 239 (30). HR-MS calcd. for C13H9FS
[M+]: 254.0377; found: 254.0357.
(3-Fluorophenyl)-2,3-dichlorophenylsulfide (3i)
Colorless viscous oil. IR (KBr, cm–1): 1597, 1474, 1399,
(3,4,5-Trifluorophenyl)-4-bromophenylsulfide (4b)
1
1086, 881, 781, 678. H NMR (400 MHz, CDCl3) d: 6.89
White soild. Mp (recrystallization in petroleum ether)
(d, J = 8.0 Hz, 2H), 7.02–7.13 (m, 2H), 7.20 (d, J = 8.0 Hz,
1H), 7.31–7.40 (m, 2H). 13C NMR (100 MHz, CDCl3) d:
116.0 (d, J = 20.8 Hz, 1C), 120.0 (d, J = 22.4 Hz, 1C),
127.9 (d, J = 28.1 Hz, 1C), 128.5–129.0 (m, 1C), 129.9,
130.6, 131.2 (d, J = 7.9 Hz, 1C), 131.7, 134.0, 134.8 (d, J =
7.5 Hz, 1C), 138.4, 163.2 (d, J = 248.3 Hz, 1C). 19F NMR
(376 MHz, CDCl3) d: –110.03 (dd, J = 13.9, 9.4 Hz, 1F).
MS (EI) m/z (%): 272 (M+, 100), 202 (15). HR-MS calcd.
for C12H7Cl2FS [M+]: 271.9630; found: 271.9651.
56.0–58.0 8C. IR (KBr, cm–1): 3132, 1613 1518, 855, 811,
1
759. H NMR (400 MHz, CDCl3) d: 6.87 (d, J = 7.2 Hz,
2H), 7.27 (d, J = 7.6 Hz, 2H), 7.51 (d, J = 6.8 Hz, 2H). 13C
NMR (100 MHz, CDCl3) d: 113.8 (dd, J = 16.7, 6.1 Hz,
2C), 123.0, 132.3 (d, J = 16.7 Hz, 1C), 132.9 (2C), 134.1
(2C), 137.5, 140.0, 151.3 (d, J = 247.3 Hz, 2C). 19F NMR
(376 MHz, CDCl3) d: –132.11 ~ –132.19 (m, 2F), –160.92
~ –161.07 (m, 1F). MS (EI) m/z (%): 318 (M+, 100), 239
(10). HR-MS calcd. for C12H6BrF3S [M+]: 317.9326; found:
317.9248.
(3-Fluorophenyl)-4- hydroxylphenylsuifide (3j)
Colorless viscous oil. IR (KBr, cm–1): 3391, 2925, 1599,
(3,4,5-Trifluorophenyl)-4-chlorophenylsulfide (4c)
1
1493, 878, 830, 774, 673. H NMR (400 MHz, CDCl3) d:
Colorless viscous oil. IR (KBr, cm–1): 3134, 1614, 1516,
5.44 (s, 1H), 6.75–6.80 (m, 2H), 6.85–6.92 (m, 3H), 7.16
(dd, J = 8.0, 8.0 Hz, 1H), 7.40 (d, J = 8.8 Hz, 2H). 13C
NMR (100 MHz, CDCl3) d: 112.4 (d, J = 21.3 Hz, 1C),
114.1 (d, J = 23.5 Hz, 2C), 116.7, 122.8 (2C), 130.1 (d, J =
8.3 Hz, 2C), 136.5, 141.5, 156.4, 163.0 (d, J = 246.5 Hz,
1C). 19F NMR (376 MHz, CDCl3) d: –111.61 (dd, J = 15.4,
9.0 Hz, 1F). MS (EI) m/z (%): 220 (M+, 100), 201 (25). HR-
MS calcd. for C12H9FOS [M+]: 220.0358; found: 220.0347.
1
896, 841, 824, 759. H NMR (400 MHz, CDCl3) d: 6.83
(dd, J = 6.8, 6.8 Hz, 2H), 7.34 (s, 4H). 13C NMR
(100 MHz, CDCl3) d: 113.5 (dd, J = 16.7, 6.1 Hz, 2C),
120.1, 129.4 (d, J = 18.2 Hz, 1C), 129.9, 131.4, 132.5 (d, J =
50.8 Hz, 1C), 134.0, 135.0, 138.7 (d, J = 243.4 Hz, 1C),
151.3 (d, J = 247.2 Hz, 2C). 19F NMR (376 MHz, CDCl3)
d: –132.11 ~ –132.19 (m, 2F), –160.92 ~ –161.07 (m, 1F).
MS (EI) m/z (%): 274 (M+, 100), 239 (40). HR-MS calcd.
for C12H6ClF3S [M+]: 273.981; found: 273.972.
(3-Fluorophenyl)-2-aminophenylsulfide (3k)
Red viscous oil. IR (KBr, cm–1): 3469, 3375, 1609, 1479,
(3,4,5-Trifluorophenyl)-4-fluorophenylsulfide (4d)
1
Colorless viscous oil. IR (KBr, cm–1): 2964, 1614, 1517,
879, 750, 673. H NMR (400 MHz, CDCl3) d: 4.24 (s, 2H),
1
6.70–6.79 (m, 4H), 6.85 (d, J = 8.0 Hz, 1 H), 7.15 (dd, J =
15.2, 7.2 Hz, 1H), 7.20 (td, J = 8.4, 1.6 Hz, 1H), 7.43 (d, J =
7.6 Hz, 1H). 13C NMR (100 MHz, CDCl3) d: 112.2 (d, J =
21.2 Hz, 1C), 113.0 (d, J = 23.5 Hz, 2C), 115.4, 118.8,
121.7, 130.1 (d, J = 8.3 Hz, 1C), 131.6, 137.6, 139.5 (d, J =
6.8 Hz, 1C), 148.9, 163.1 (d, J = 246.4 Hz, 1C).19F NMR
(376 MHz, CDCl3) d: –111.37 (dd, J = 15.1, 9.0 Hz, 1F).
1425, 1047, 834, 759. H NMR (400 MHz, CDCl3) d: 6.76
(dd, J = 3.6, 3.6 Hz, 2H), 7.09 (dd, J = 11.6, 11.6 Hz, 2H),
7.76 (dd, J = 11.6, 5.2 Hz, 2H). 13C NMR (100 MHz,
CDCl3) d: 112.3 (dd, J = 17.1, 6.2 Hz, 1C), 113.1 (d, J =
23.2 Hz, 1C), 116.1–117.1 (m, 1C), 125.2, 127.4, 132.8 (d,
J = 264.4 Hz, 1C), 135.4, 136.0, 138.2 (d, J = 249.8 Hz,
1C), 151.3 (d, J = 251.5 Hz, 2C), 163.3 (d, J = 240.4 Hz,
Published by NRC Research Press

490
Can. J. Chem. Vol. 88, 2010
1C). 19F NMR (376 MHz, CDCl3) d: –152.71 ~ –152.86 (m,
2F), –182.25 ~ –183.40 (m, 1F). MS (EI) m/z (%): 258 (M+,
100), 238 (35). HR-MS calcd. for C12H6F3S [M+]: 258.0126;
found: 258.0114.
J = 26.3, 20.3 Hz, 1F). MS (EI) m/z (%): 238 (100), 308
(M+, 40). HR-MS calcd. for C12H5Cl2F3S [M+]: 307.9441;
found: 307.9462.
(3,4,5-Trifluorophenyl)-4-hydroxylphenylsulfide (4j)
White solid. Mp (recrystallization in petroleum ether)
68.7–70.1 8C. IR (KBr, cm–1): 3403, 3133, 1614, 1516,
(3,4,5-Trifluorophenyl)-4-nitrophenylsulfide (4e)
Yellow solid. Mp (recrystallization in petroleum ether)
110.2–111.0 8C. IR (KBr, cm–1): 3130, 1617, 1505, 1401,
1401, 1045, 832, 758, 619. H NMR (400 MHz, CDCl3) d:
1
1
1087, 854, 739. H NMR (400 MHz, CDCl3) d: 7.15 (dd,
5.07 (s, 1H), 6.69 (dd, J = 13.2, 13.2 Hz, 2H), 6.88 (d, J =
5.2 Hz, 2H), 7.40 (d, J = 9.2 Hz, 2H). 13C NMR (100 MHz,
CDCl3) d: 110.0 (dd, J = 17.4, 6.1 Hz, 2C), 117.0 (2C),
122.1, 135.6, 136.2 (d, J = 31.90 Hz, 2C), 138.9, 151.3 (d,
J = 250.3 Hz, 2C), 156.8. 19F NMR (376 MHz, CDCl3) d:
–153.25 ~ –153.37 (m, 2F), –183.69 (dd, J = 25.9, 19.9 Hz,
1F). MS (EI) m/z (%): 256 (M+, 100), 195 (25). HR-MS
calcd. for C12H7F3OS [M+]: 256.0170; found: 256.0159.
J = 6.8, 6.8 Hz, 2H), 7.26–7.31 (m, 2H), 8.15 (dd, J = 9.6,
4.4 Hz, 2H). 13C NMR (100 MHz, CDCl3) d: 117.8–118.0
(m, 2C), 124.4 (2C), 128.4 (2C), 139.3, 141.8, 145.1, 146.4,
151.6 (d, J = 244.0 Hz, 2C). 19F NMR (376 MHz, CDCl3) d:
–130.60 (dd, J = 22.6, 9.0 Hz, 2F), –156.68 ~ –156.78 (m,
1F). MS (EI) m/z (%): 285 (M+, 100), 238 (50), 255 (25).
HR-MS calcd. for C12H6F3NO2S [M+]: 285.0071; found:
285.0060.
(3,4,5-Trifluorophenyl)-2-aminophenylsulfide (4k)
(3,4,5-Trifluorophenyl)phenylsulfide (4f)
Light yellow solid. Mp (recrystallization in petroleum
ether) 66.5–66.9 8C. IR (KBr, cm–1): 3484, 3385, 3133,
1612, 1513, 1478, 1401, 832, 756, 607. 1H NMR
(400 MHz, CDCl3) d: 4.27 (s, 2H), 6.45 (dd, J = 7.2,
7.2 Hz, 2H), 6.76–6.82 (m, 2 H), 7.25–7.30 (m, 1H), 7.41
(d, J = 8.8 Hz, 1H). 13C NMR (100 MHz, CDCl3) d: 110.1
(dd, J = 17.5, 6.1 Hz, 1C), 112.4, 115.7, 119.1, 132.2, 133.5,
136.4, 137.7, 138.9, 149.0, 151.4 (d, J = 252.2 Hz, 2C). 19F
NMR (376 MHz, CDCl3) d: –152.36 (dd, J = 22. 6, 15.0 Hz,
2F), –179.93 (dd, J = 21.4, 12.4 Hz, 1F). MS (EI) m/z (%):
255 (M+, 100), 80 (30). HR-MS calcd. for C12H8F3NS [M+]:
255.0330; found: 255.0315.
1
Colorless viscous oil. Lit. value16d bp 316.3 8C. H NMR
(400 MHz, CDCl3) d: 6.81–6.84 (m, 2H), 7.37–7.74 (m,
5H). 19F NMR (376 MHz, CDCl3) d: –161.80 (t, J =
19.3 Hz, 1F), –132.62 (t, J = 12.0 Hz, 2F).
(3,4,5-Trifluorophenyl)-2,4-dimethylphenylsulfide (4g)
Cololress viscous oil. IR (KBr, cm–1): 2917, 1613, 1515,
1424, 1317, 1046, 899, 875, 758. 1H NMR (400 MHz,
CDCl3) d: 2.34 (d, J = 9.2 Hz, 6H), 6.61 (dd, J = 7.2,
7.2 Hz, 2H), 7.04 (d, J = 7.6 Hz, 1H), 7.15 (s, 1H), 7.36 (d,
J = 8.4 Hz, 1H). 13C NMR (100 MHz, CDCl3) d: 20.8 (d, J =
24.9 Hz, 1C), 22.7, 110.7 (dd, J = 17.1, 6.1 Hz, 2C), 126.6,
128.1, 132.1, 134.7, 136.1 (d, J = 27.3 Hz, 1C), 138.8,
140.4, 142.0, 151.4 (d, J = 250.4 Hz, 2C). 19F NMR
(376 MHz, CDCl3) d: –153.34 (dd, J = 19.9, 16.9 Hz,
2F), –183.71 ~ –183.86 (m, 1F). MS (EI) m/z (%): 268
(M+, 100), 91 (50), 218 (25). HR-MS calcd. for C14H11F3S
[M+]: 268.053; found: 268.133.
(3,4,5-Trifluorophenylthio)-3-propanoic acid (4m)
Yellow solid. Mp (recrystallization in petroleum ether)
68.9–71.2 8C. IR (KBr, cm–1): 3133, 1709, 1610, 1519,
1399, 1232, 1047, 810, 756, 656. 1H NMR (400 MHz,
CDCl3) d: 2.68–2.72 (m, 2H), 3.15 (t, J = 7.2 Hz, 2H), 7.00
(dd, J = 7.6, 6.8 Hz, 2H).13C NMR (100 MHz, CDCl3) d:
27.6, 33.4, 112.3 (d, J = 22.8 Hz, 1C), 117.8 (d, J =
17.5 Hz, 1C), 133.3, 136.9 (d, J = 253.5 Hz, 1C), 150.4 (d,
J = 254.8 Hz, 2C), 172.5. 19F NMR (376 MHz, CDCl3) d:
–132.36 (dd, J = 24.4, 19.9 Hz, 2F), –161.00 ~ –161.13 (m,
1F). MS (EI) m/z (%): 236 (M+, 100), 177 (45). HR-MS
calcd. for C9H7F3O2S [M+]: 236.2109; found: 236.1989.
(3,4,5-Trifluorophenyl)-4-isopropylphenylsulfide (4h)
Colorless viscous oil. IR (KBr, cm–1): 2963, 1613, 1516,
1425, 1317, 1233, 897, 831, 758. 1H NMR (400 MHz,
CDCl3) d: 1.26 (t, J = 7.6 Hz, 6H), 2.30 (t, J = 7.2 Hz, 1H),
6.77 (dd, J = 8.4, 6.4 Hz, 2H), 7.25 (d, J = 8.8 Hz, 2H), 7.37
(d, J = 8.4 Hz, 2H). 13C NMR (100 MHz, CDCl3) d: 23.8
(2C), 33.9, 112.2 (dd, J = 17.1, 6.1 Hz, 2C), 127.5 (d, J =
33.1 Hz, 1C), 128.7, 133.7 (d, J = 28.7 Hz, 1C), 134.6 (d, J =
4.8 Hz, 1C), 136.0, 136.8, 139.3, 150.2, 151.3 (d, J =
247.7 Hz, 2C). 19F NMR (376 MHz, CDCl3) d: –153.17 ~
–153.28 (m, 2F), –182.87 ~ –183.00 (m, 1F). MS (EI) m/z
(%): 282 (M+, 100), 267 (95), 105 (35). HR-MS calcd. for
C15H13F3S [M+]: 282.0690; found: 282.0710.
(3,4,5-Trifluorophenyl)benzylsulfide (4n)
White solid. Mp (recrystallization in petroleum ether)
50.0–50.9 8C. IR (KBr, cm–1): 3414, 3132, 1613, 1519,
1505, 1401, 1049, 823, 719, 694. 1H NMR (400 MHz,
CDCl3) d: 4.08 (s, 2H), 6.88 (dd, J = 7.2, 6.0 Hz, 2H),
7.21–7.33 (m, 5H). 13C NMR (100 MHz, CDCl3) d: 39.5,
110.7, 113.5, 114.1 (d, J = 17.1 Hz, 1C), 116.4, 119.2,
127.9, 129.0, 132.6, 136.5, 151.3 (d, J = 26.0 Hz, 2C),
163.0–161.7 (m, 1C). 19F NMR (376 MHz, CDCl3) d: –132.96
(m, 2F), –161.69 (d, J = 17.1 Hz, 1F). MS (EI) m/z (%): 254
(M+, 100), 163 (15). HR-MS calcd. for C13H9F3S [M+]:
254.0377; found: 254.0364.
(3,4,5-Trifluorophenyl)-2,3-dichlorophenylsulfide (4i)
Colorless solid. Mp (recrystallization in petroleum ether)
55.4–57.2 8C. IR (KBr, cm–1): 3131, 1616, 1518, 1401, 796,
1
770. H NMR (400 MHz, CDCl3) d: 6.92–7.06 (m, 3H), 7.13
(dd, J = 16.0, 8.4 Hz, 1H), 7.39 (d, J = 8.0 Hz, 1H). 13C
NMR (100 MHz, CDCl3) d: 111.1 (d, J = 22.0 Hz, 1C),
116.5 (dd, J = 16.3, 6.0 Hz, 2C), 127.7, 129.3 (d, J =
26.2 Hz, 2C), 132.6, 134.2, 136.6, 140.0 (d, J = 245.0 Hz,
1C), 151.5 (d, J = 242.3 Hz, 2C). 19F NMR (376 MHz,
CDCl3) d: –131.44 (dd, J = 24.4, 20.3 Hz, 2F), –158.49 (dd,
Bis(3-fluorophenyl)sulfide (5a)
Yellow oil. IR (KBr, cm–1): 3064, 1597, 1472, 881, 815,
777, 677. 1H NMR (400 MHz, CDCl3) d: 7.05 (dd, J =
10.4, 8.4 Hz, 2H), 7.22–7.26 (m, 2H), 7.31–7.41 (m, 4 H).
13C NMR (100 MHz, CDCl3) d: 110.4, 111.2 (dd, J = 15.7,
Published by NRC Research Press

Yu et al.
491
(5) (a) Taniguchi, N. J. Org. Chem. 2004, 69 (20), 6904. doi:10.
1021/jo040184q. PMID:15387621.; (b) Jammi, S.; Barua, P.;
Rout, L.; Saha, P.; Punniyamurthy, T. Tetrahedron Lett.
2008, 49 (9), 1484. doi:10.1016/j.tetlet.2007.12.118.
6.1 Hz, 1C), 113.2, 116.0, 118.9, 134.2, 139.9 (d, J =
252.3 Hz, 2C), 151.6 (dd, J = 249.4, 6.1 Hz, 2C), 162.8–
161.9 (m, 2C). 19F NMR (376 MHz, CDCl3) d: –117.87 (dd,
J = 15.4, 9.0 Hz, 2F). MS (EI) m/z (%): 222 (M+, 100), 203
(25). HR-MS calcd. for C12H8F6S [M+]: 222.0315; found:
222.0322.
(6) Wong, Y.-C.; Jayanth, T. T.; Cheng, C.-H. Org. Lett. 2006, 8
(24), 5613. doi:10.1021/ol062344l. PMID:17107085.
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Synlett 2004, 1254. doi:10.1055/s-2004-825584.; (b) Herrero,
Bis(3,4,5-trifluorophenyl)sulfide (5b)
´
M. T.; SanMartin, R.; Domınguez, E. Tetrahedron 2009, 65
White solid. Mp (recrystallization in petroleum ether)
87.8–89.1 8C. IR (KBr, cm–1): 3133, 1617, 1514, 1402,
(7), 1500. doi:10.1016/j.tet.2008.11.062.; (c) Chen, Y.-J.;
Chen, H.-H. Org. Lett. 2006, 8 (24), 5609. doi:10.1021/
ol062339h. PMID:17107084.; (d) Zhu, D.; Xu, L.; Wu, F.;
Wan, B. Tetrahedron Lett. 2006, 47 (32), 5781. doi:10.
1016/j.tetlet.2006.05.178.
1
1043, 690, 610, 478. H NMR (400 MHz, CDCl3) d: 7.08–
7.16 (m, 4H). 13C NMR (100 MHz, CDCl3) d: 111.1 (dd, J =
16.1, 6.1 Hz, 4C), 134.3 (2C), 139.9 (d, J = 252.5 Hz, 2C),
151.6 (d, J = 249.80 Hz, 4C). 19F NMR (376 MHz, CDCl3)
d: –132.07 (t, J = 16.5 Hz, 4F), –159.54 ~ –159.69 (m, 2F).
MS (EI) m/z (%): 294 (M+, 100), 163 (95). HR-MS calcd.
for C12H4F6S [M+]: 293.9938; found: 293.9921.
ˆ
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Acknowledgements
2000,
2
(14), 2019. doi:10.1021/ol005832g. PMID:
We thank the National Key Technology R&D Program
(No. 2007BAI34B00), National Natural Science Foundation
of China (20876147, 20676123), and Opening Foundation
of Zhejing Provincial Top Key Pharmaceutical Discipline
for financial support.
10891219.
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