Diarylation of chalcogen elements using arylboronic acids via copper- or palladium-catalyzed oxidative coupling

Article abstract of DOI:10.1016/j.tet.2016.08.012

Transition metal-catalyzed diarylations of sulfur, selenium and tellurium were achieved using arylboronic acids in air. A copper-catalyzed reaction of sulfur or selenium efficiently yielded numerous symmetrical diaryl sulfides or selenides in the presence of NH₄BF₄. However, the diarylation of tellurium was not possible using this method, and required a palladium catalyst in the presence of KI and air for the reaction to proceed.

Full text of DOI:10.1016/j.tet.2016.08.012

Accepted Manuscript
Diarylation of chalcogen elements using arylboronic acids via copper- or palladium-
catalyzed oxidative coupling
Nobukazu Taniguchi
PII:
S0040-4020(16)30770-0
10.1016/j.tet.2016.08.012
TET 27993
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 27 June 2016
Revised Date: 31 July 2016
Accepted Date: 4 August 2016
Please cite this article as: Taniguchi N, Diarylation of Chalcogen Elements Using Arylboronic Acids via
Copper- or Palladium-Catalyzed Oxidative Coupling, Tetrahedron (2016), doi: 10.1016/j.tet.2016.08.012.
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ACCEPTED MANUSCRIPT
Graphical Abstract
Diarylation of Chalcogen Elements Using
Arylboronic Acids via Copper- or
Leave this area blank for abstract info.
Palladium-Catalyzed Oxidative Coupling
Nobukazu Taniguchi
Department of Chemistry, Fukushima Medical University, Fukushima 960-1295, Japan

ACCEPTED MANUSCRIPT
1
Tetrahedron
journal homepage: www.elsevier.com
Diarylation of Chalcogen Elements Using Arylboronic Acids via Copper- or
Palladium-Catalyzed Oxidative Coupling
Nobukazu Taniguchia ,
a Department of Chemistry, Fukushima Medical University, Fukushima 960-1295, Japan
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
Transition metal-catalyzed diarylations of sulfur, selenium and tellurium were achieved using
aylboronic acids in air. A copper-catalyzed reaction of sulfur or selenium efficiently yielded
numerous symmetrical diaryl sulfides or selenides in the presence of NH4BF4. However, the
diarylation of tellurium was not possible using this method, and required a palladium catalyst in
the presence of KI and air for the reaction to proceed.
Available online
2009 Elsevier Ltd. All rights reserved.
Keywords:
Copper Catalyst
Diarylation
Chalcogen
Arylboronic Acid
Oxidative Coupling
———
Corresponding author. Tel.: +81-24-547-1369; fax: +81-24-547-1369; e-mail: taniguti@fmu.ac.jp

ACCEPTED MANUSCRIPT
2
Tetrahedron
(a) Sulfidation of aryl halides with K2CO3
1. Introduction
1.cat.CuI
K2CO3 / DMF,
80-90 ºC
The transition metal-catalyzed formation of carbon−chalcogen
bonds is an important reaction in organic syntheses. This method
has been extensively researched and utilized to date.1,2 Herein
produced compounds have been widely employed as convenient
intermediates or reagents.3
SH
Ar
+
Ar-X
S8
2. NaBH4
(b) Sulfidation of aryl boronic acid with NaOH
cat.CuI, NaOH
To synthesize organochalcogenides, chalcogenols or
dichalcogenides are often used as
a
chalcogen source.2
S
+
S8
Ar-B(OH)2
+
Ar'-NO2
Ar
Ar'
PEG200, 100 ºC
Alternatively, procedures using chalcogens are also reported.
Among them, Grignard reaction4 or coupling reaction of aryl or
alkyl halides with sodium chalcogenides5 are routinely performed.
However, the use of a transition metal-catalyzed synthesis is
limited, either because of the formaton of stable metal−chalcogen
compounds as intermediates or because of the poor reactivity of
transition metals with chalcogens.
(c) Sulfidation of aryl halides
cat.CuI-bpy, Mg
Y
+
Ar-X
Y
Ar
Ar
S
DMF, 110 ºC,
under N2
Y = S or Se
(d) Sulfidation of arylboronic acids
cat.CuF2
Recently, some methods have been exploited for the arylation
of chalcogens. For instance, procedures involving the formation
Ar
+
Ar-B(OH)2
Y
Ar
S
2-
Pyridine, DMSO,
100 ºC, under N2
Se
of Sn + 1 following a reaction of sulfur with hydroxide were
Y = S or Se
or Ar
Ar
reported. Copper-catalyzed sulfidation of aryl halides using
K2CO3 followed by NaBH4 reduction affords aryl thiols (Scheme
1a).6a A three component coupling using ArB(OH)2, ArNO2 and
sulfur was also performed in the presence of NaOH (Scheme
1b)6b On the other hand, using magnesium as a reductant, diaryl
sulfides or selenides were produced from aryl halides in the
presence of CuI catalyst (Scheme 1c).7 Furthermore, a CuF2-
catalyzed reaction using arylboronic acids yields disulfides or
monoselenides (Scheme 1d).8 The reaction is performed under
nitrogen atmosphere, and is necessary for DMSO as an oxidant.
Table 1. Investigation of suitable reaction conditions
4-MeC6H4B(OH)2 2b,
[Cu]-L (1:1, 10 mol%),
S
Additive
S8
DMSO, H2O, air
100 ºC, 18 h
1
3b
Entry
1
Cu-L (mol%)
Add.
3b (%)
0
CuI
none
2
CuI-bpy
none
54
0
These abovementioned reactions (Schemes 1a−1d) are
performed under basic or reductive conditions or require excess
reagents and therefore are not efficient methods for synthesizing
organochalcogenides involving various functional groups.
Selective mono-sulfide synthesis is not easy owing to the
generation of disulfides or trisulfides. Moreover, it is not possible
to use tellurium in these reactions. Therefore, there is a need to
develop of an efficient method for the diarylation of chalcogens,
including tellurium.
3
CuI-TMEDA
CuI-Phen·H2O
CuI-Phen·H2O
CuI-Phen·H2O
CuI-Phen·H2O
CuCl-Phen·H2O
CuBr-Phen·H2O
CuCl2-Phen·H2O
PdCl2-Phen·H2O
NiCl2-Phen·H2O
none
4b
none
38
50
70
79
76
75
73
0
5
none
6
NH4PF6
NH4BF4
NH4BF4
NH4BF4
NH4BF4
NH4BF4
NH4BF4
7
8
9
To overcome the aforementioned problems, the labilization of
stable metal−chalcogen complexes formed as intermediates is
required. It is hypothesized that the oxidation of these complexes
is the most efficient method. The arylation of chalcogen elements
with arylboronic acids in air was investigated by adopting
conditions similar to those of the copper-catalyzed coupling of
dichalcogenides with organoboronic acids.9, 10
10
11
12
0
aA mixture of 1 S8 (0.025 mmol), 2 (0.5 mmol), Metal-Phen·H2O (1:1, 10
ml%) and additive (0.05 mmol) was treated in DMSO (0.2 mL) and H2O (0.1
mL).
From numerous experiments, the copper-catalyzed arylation
of sulfur or selenium was found to occur in air. The reaction
involving tellurium smoothly proceeded in the presence of a
palladium catalyst, KI, and air. In this article, these developed
methodology will be described.
bIsolated yields after silica gel chromatography.
To establish suitable conditions, a combination of sulfur and
4-tolylboronic acid was initially evaluated (Table 1). When the
reaction was performed using CuI catalyst, di(4-tolyl) sulfide 3b
was not formed (Entry 1). On the contrary, amine ligands
promoted the reaction to a small extent (Entries 2−5). Fortunately,
the addition of NH4PF6 or NH4BF4 improved the production of
3b to 70 and 79% yield, respectively (Entries 6−7).11 The
reactions using other copper salts also gave good results (Entries
8−10). However, it was observed that palladium chloride or
nickel chloride catalysts could not stimulate the reaction (Entries
11−12).
2. Results and Discussion
Scheme 1. Existing synthetic methods for the diarylation
of chalcogen elements

ACCEPTED MANUSCRIPT
3
In the procedure, when a competitive reaction in the
Table 2. Copper-catalyzed diarylation of chalcogen element
presence of both sulfur and selenium was performed, a
sulfidation of arylboronic acid was predominate (Scheme 2).
using arylboronic acids
ArB(OH)2 2,
CuI-Phen•H2O(1:1, 10 mol%),
NH4BF4
To elucidate the reaction mechanism, several experiments
were carried out. When a mixture of sulfur and 4-tolylboronic
acid were then reacted in the absence of oxygen, the
corresponding sulfide was obtained in only 27% yield (Scheme
3).
Ar2Y
Y
1
DMSO, H2O, air, 100 ºC
3
Y = S8 or Se
Entry
1
Y
Ar
Time (h)
3 (%)b
80(3a)
74(3a’)
79(3b)
67(3b’)
78(3c)
73(3c’)
72(3d)
74(3d’)
87(3e)
61(3f)
72(3f’)
70(3g)
78(3g’)
82(3h)
83(3h’)
85(3i)
73(3j)
34(3j’)
70(3k)
60(3k’)
0
S8
Se
S8
Se
S8
Se
S8
Se
S8
S8
Se
S8
Se
S8
Se
S8
S8
Se
S8
Se
S8
Te
Ph
18
36
18
36
18
36
36
36
36
36
36
18
36
24
36
36
36
36
18
36
18
18
The reactivity of copper-chalcogenides considered as
intermediates was evaluated (Scheme 4). Using CuS or CuSe,
the reaction gave the corresponding chalcogenides in 55 and 67%
yield respectively. However, the reaction did not proceed in the
presence of Cu2S. Similarly, sulfidation of copper-phenythiolate
was examined (Scheme 5).12 The reaction afforded the desired
sulfide in 60% yields.
2
3
4-MeC6H4
4-MeOC6H4
4-ClC6H4
4
5
6
7
These results indicate that oxygen present in air is necessary
for the diarylation of chalcogen, and it seems that DMSO also
works as a weak oxidant. Furthermore, the reactions of
copper(II)-chalcogenide complexes with arylboronic acids can
produce diaryl sulfides or selenides except for Cu(I)2S.
A plausible reaction mechanism is illustrated in Figure 1.13
After the formation of ArCu(I)Ln, the insertion of chalcogenides
affords ArYnCu(I)Ln. Sequentially, the complex is oxidized to
ArYnCu(II)X, and ArYnAr is produced via transmetallation and
reductive elimination. Finally, ArYnAr affords ArYAr following
the reaction with ArCu(I)X.
8
9
4-OHCC6H4
10
11
12
13
14
15
16
17
18
19
20
21
22
4-MeO2CC6H4
2-MeC6H4
2-MeOC6H4
2-ClC6H4
2-OHCC6H4
Scheme 3. Diarylation of sulfur in the absence of oxygen
4-MeC6H4B(OH)2
,
CuI-Phen•H2O(1:1, 10 mol%),
NH4BF4
S
1-Naphtyl
S8
DMSO, H2O, 100 ºC, 18 h
under N2
27%
PhCH2CH2
4-MeC6H4
0
Scheme 4. Reactivity of CuS, CuSe and Cu2S
4-MeC6H4B(OH)2
Phen•H2O, NH4BF4
,
aA mixture of 1 S8 (0.025 mmol) or Se (0.02 mmol), 2 (0.5 mmol), CuI-
Phen·H2O (1:1, 10 ml%) and NH4BF4 (0.05 mmol) was treated in DMSO (0.2
mL) and H2O (0.1 mL).
Y
CuY
DMSO, H2O, air, 100 ºC
18 h
Y = S: 55%
Y = Se:67%
bIsolated yields after silica gel chromatography.
4-MeC6H4B(OH)2
Phen•H2O, NH4BF4
,
Scheme 2. A reactivity of sulfur and selenium
4-MeC6H4B(OH)2 2b,
S
Cu2S
CuI-Phen•H2O (1:1, 10 mol%),
DMSO, H2O, air, 100 ºC
18 h
S
S8(0.025 mmol)
+
NH4BF4
Not detected
(
(
S)2
+
+
Se (0.02 mmol)
DMSO, H2O, air
100 ºC, 18 h
3b
3bb
Scheme 5. A reactiity of PhSCu
Phen•H2O
NH4BF4
Se
Se)2
SPh
PhSCu
+
B(OH)2
(0.2 mmol)
3b'b'
3b'
DMSO/H2O, air,
100 ºC, 18h
(0.1 mmol)
3
3b / 3bb / 3b' / 3b'b' = 20 / 40 / 40 / 0
The ratio were determined by 1H NMR
60%
According to the developed procedure, numerous diarylations
of sulfur or selenium were then investigated (Table 2). The
procedure afforded expected diaryl monosulfides or selenides in
good yields (Entries 1−20). Arylboronic acids involving carbonyl
groups were also synthesized (Entries 9−11, 17−18). Regrettably,
the reaction using alkylboroic acids could not produce the
corresponding product and complex mixture was obtained (Entry
21). The reaction of tellurium hardly proceeded (Entry 22).

ACCEPTED MANUSCRIPT
4
Tetrahedron
Figure 1. Plausible reaction mechanism
Table 4. Palladium-catalyzed diarylation of tellurium using
Ar-CuILn
arylboronic acids
Ar2Y
Ar2Yn
CuIXLn
ArB(OH)2 2,
ArB(OH)2
CuI-Phen(1:1, 10 mol%),
KI
1/4O2 or DMSO
Te
1
Ar
Ph
Ar2Te
ArYn
Ar-CuILn
CuIILn
DMSO, H2O, air, 100 ºC
4
Ar
Entry
(h)
4 (%)b
Yn
ArYn-CuILn
1
2
3
4
5
6
7
8
18
74(4a)
60(4b)
62(4c)
65(4l)
75(4d)
57(4e)
72(4f)
77(4k)
ArB(OH)2
ArYn
X
CuIILn
4-MeC6H4
4-MeOC6H4
4-BrC6H4
18
18
42
18
18
42
42
1/4O2 or DMSO
4-ClC6H4
Numerous diaryl sulfides and selenides were prepared using
the copper catalyzed synthesis. However, arylation of tellurium
4-OHCC6H4
4-MeO2CC6H4
1-Naphtyl
could not be archieved.1e, 14
Therefore, a transition metal-catalyzed reaction of tellurium
with phenylboronic acid was screened under various conditions
(Table 3). When CuI was used as the catalyst, the formation of
di(4-tolyl) telluride 3a was not observed at all and tellurium was
recovered (Entry 1). Notably, the addition of KI to the reaction
mixture afforded 3a in 18% yield with a recovery of tellurium
(Entry 2).
aA mixture of 1 (0.2 mmol), 2 (0.5 mmol), CuI-Phen·H2O (1:1, 10 ml%) and
KI (0.2 mmol) was treated in DMSO (0.2 mL) and H2O (0.1 mL).
bIsolated yields after silica gel chromatography.
To investigate the reaction mechanism, the reaction in the
absence of oxygen was examined (Scheme 6). However, the
corresponding telluride was not synthesized in the absence of
oxygen. This indicates that KI promotes the reaction only in the
presence of oxygen. Furthermore, the reaction in the presence of
I2 was performed (Scheme 7). The reaction under N2 gave the
corresponding diaryl telluride in only 17% yield with a formation
of aryl iodide, although the reaction under air was 57% yield.
Sequentially, a reaction of Te with KI was examined (Scheme 8).
When the reaction in the absence of PdCl2 catalyst was
performed, Te powder was recovered. In the presence of PdCl2
catalyst, Te completely consumed. These results appears that the
generation of I2 from KI reacts with Te, and TeI4 are produced
(Scheme 9).16 This is converted to K2TeO3 by the reaction with
H2O in the presence of K+. Finally, potassium tellurite affords Te
in the presence of H2O.16 It seems that the reactivity is higher
than Te powder because herein produced Te is a flesh atom or
particle.17 From these results, it is considered that the generated
tellurium is used in the catalytic cycle. A plausible reaction
mechanism is given below (Figure 2).12
Fortunately, when PdCl2 catalyst was employed instead of CuI
in the presence of KI, the yield of 3a was 74% without the
formation of iodobenzene (Entry 3).15 However, the absence of
KI could not promote the reaction and Te powder was recovered
(Entry 5). Although reactions using other additives or metal
catalysts were surveyed, satisfactory results were not obtained
(Entries 6−9). The addition of KI could scarcely promote the
reaction in the absence of metal catalysts (Entry 10).
Based on the developed procedure, diarylations of tellurium
were then performed. As shown in table 4, the synthesis of
numerous diaryl tellurides in good yields could be achieved.
Table 3. Investigation of suitable conditions
PhB(OH)2 2a,
[M]-Phen•H2O(1:1, 10 mol%),
Additive
Ph2Te
Te
1
DMSO, H2O, air, 100 ºC,
18 h
3a
Entry
Metal (mol%)
Additive
none
KI
3a (%)b
0
1
CuI(10)
Scheme 6. Diarylation of tellurium in the absence of oxygen
2
18
4-MeC6H4B(OH)2
,
3
PdCl2(10)
KI
74
PdCl2-Phen•H2O(1:1, 10 mol%),
KI
Te
4
KI
70
Te
DMSO, H2O, 100 ºC, 18 h,
under N2
5
none
KBr
NH4PF6
KI
0
trace
6
trace
trace
20
Scheme 7. Diarylation of tellurium in the presence of I2
7
4-MeC6H4B(OH)2
,
8
Pd(OAc)2(10)
NiBr2(10)
none
PdCl2-Phen•H2O(1:1, 10 mol%),
I2 (1 equiv.)
I
Te
9
KI
18
+
Te
DMSO, H2O, 100 ºC, 18 h,
10
KI
trace
Under N2: 17%
Under Air: 57%
10%
5%
aA mixture of 1 (0.2 mmol), 2 (0.5 mmol), CuI-Phen·H2O (1:1, 10 ml%) and
additive (0.2 mmol) was treated in DMSO (0.2 mL) and H2O (0.1 mL).
Scheme 8. Reactivity of tellurium
bIsolated yields after silica gel chromatography.

ACCEPTED MANUSCRIPT
5
KI (1 equiv.)
The title compound was obtained as white solid (33.6 mg,
No reaction
Te
Te
(Te was recovered.)
79%); mp 53.0−54.5 °C; [Found: C, 78.41; H, 6.53. C14H14S
DMSO, H2O, 100 ºC, 18 h, air
1
requires C, 78.45; H, 6.58%]; nmax (CHCl3) 2923, 1491 cm-1; H
NMR (270 MHz, CDCl3) δ 7.22 (d, J = 8.2 Hz, 4H), 7.19 (d, J =
8.2 Hz, 4H), 2.31 (s, 6H); 13C NMR (67.5 MHz, CDCl3) δ 136.9,
132.6, 131.0, 129.9, 21.0.
4.2.2. Di(4-methoxyphenyl) sulfide (3c)2 g
KI (1 equiv.),
PdCl2-Phen•H2O(1:1, 10 mol%),
Suspension
(Te was consumed.)
DMSO, H2O, 100 ºC, 18 h, air
The title compound was obtained as white solid (38.5 mg, 78%);
mp 43.7−44.0 °C; [Found: C, 56.32; H, 3.14. C14H14O2S requires
C, 56.48; H, 3.16.%]; nmax (CHCl3) 2960, 2837, 1592, 1492, 1244
Scheme 9. Reaction of tellurium with KI
H2O
K+
2I2
K2TeO3
Te + KOH + O2
TeI4
Te
1
cm-1; H NMR (270 MHz, CDCl3) δ 7.27 (d, J = 8.9 Hz, 4H),
powder
O2
cat.Pd
KI
particle
or atom
6.83 (d, J = 8.9 Hz, 4H), 3.78 (s, 6H); 13C NMR (67.5 MHz,
CDCl3) δ 159.0, 132.7, 127.4, 114.7, 55.3;
Figure 2. A plausible mechanism
PdIIX2Ln
4.2.3. Di(4-chlorophenyl) sulfide (3d)
ArB(OH)2
X-, 1/2O2
or I2
The title compound was obtained as white solid (36.5 mg, 72%);
mp 94.8−95.4 °C; [Found: C, 71.88; H, 4.46. C20H14Se requires
C, 72.07; H, 4.23%]Anal. Calcd for C12H8SCl2: C, 56.48; H,
3.16. Found: C, 56.61; H, 3.25.; nmax (CHCl3) 1474, 1389 cm-1;
1H NMR (270 MHz, CDCl3) δ 7.29−7.22 (m, 8H); 13C NMR
(67.5 MHz, CDCl3) δ 133.9, 133.4, 132.3, 129.5.
KI
O2
Pd0Ln
Ar-PdIIXLn
Te
cat.Pd
Ar2Te
PdIILn
ArTe
ArTe
X
PdIILn
4.2.4. Di(4-formylphenyl) sulfide (3e)
Ar
ArB(OH)2
The title compound was obtained as white solid (42.5 mg, 88%);
mp 119.0−121.5 °C; [Found: C, 68.88; H, 4.19. C14H10O2S
requires C, 69.40; H, 4.16%]; nmax (CHCl3) 2976, 2837, 1700,
3. Conclusion
1
1589, 1301 cm-1; H NMR (270 MHz, CDCl3) δ 10.00 (s, 2H),
7.87−7.82 (m, 4H), 7.52−7.48 (m, 4H); 13C NMR (67.5 MHz,
CDCl3) δ 191.1, 142.4, 135.2, 130.9, 130.5.
In conclusion, copper-catalyzed diarylation of sulfur or
selenium element was achieved using arylboronic acids in air.
The procedure afforded symmetrical mono-sulfides or selenides
with numerous functional groups in good yields. Furthermore,
the employment of a palladium catalyst instead of the copper
catalyst could result in the diarylation of tellurium in the presence
of KI in air.
4.2.5. Di(4-methylcorboxylphenyl) sulfide (3f)
The title compound was obtained as white solid (40.4 mg, 61%);
mp 87.7−88.5 °C; [Found: C, 63.29; H, 4.72. C16H14O4S requires
C, 63.56; H, 4.67%]; nmax (CHCl3) 1719, 1592, 1437, 1286 cm-1;
1H NMR (270 MHz, CDCl3) δ 8.00−7.95 (m, 4H), 7.41−7.37 (m,
4H), 3.92 (s, 6H); 13C NMR (67.5 MHz, CDCl3) δ 166.4, 140.8,
130.4, 130.3, 128.9, 52.2.
4. Experimental section
4.1. General Procedure
4.2.6. Di(2-methylphenyl) sulfide (3g)
The title compound was obtained as white solid (30.0 mg, 70%);
mp 62.5−63.3 °C; [Found: C, 78.47; H, 6.56. C14H14S requires C,
78.45; H, 6.58%]; nmax (CHCl3) 3063, 1588, 1467 cm-1; 1H NMR
(270 MHz, CDCl3) δ 7.24−7.06 (m, 8H), 2.38 (s, 6H); 13C NMR
(67.5 MHz, CDCl3) δ 138.9, 134.2, 131.1, 130.4, 127.1, 126.7,
20.4.
All reactions were carried out in air. NMR spectra were recorded
on a JEOL EX-270 spectrometer (270 MHz for 1H, 67.5 MHz for
13C). Chemical shifts are reported in δ ppm referenced to an
internal tetramethylsilane standard for 1H NMR and chloroform-d
(δ 77.0) for 13C NMR. IR spectra were measured by Perkin-
Elmer Spectrum One FT-IR spectrometer. Melting points were
measured on a BÜCHI Melting Point B-540 apparatus. Elemental
analysis was performed at the Instrumental Analysis Center for
Chemistry, Tohoku University (Japan).
4.2.7. Di(2-methoxyphenyl) sulfide (3h)
The title compound was obtained as white solid (40.1 mg, 82%);
mp 65.1−66.7 °C; [Found: C, 68.00; H, 5.85. C14H14O2S requires
C, 68.26; H, 5.73%]; nmax (CHCl3) 2972, 1579, 1477, 1242 cm-1;
1H NMR (270 MHz, CDCl3) δ 7.28−7.21 (m, 2H), 7.08−7.05 (m,
2H), 6.92−6.84 (m, 4H), 3.86 (s, 6H); 13C NMR (67.5 MHz,
CDCl3) δ 157.8, 131.9, 128.3, 122.5, 121.1, 110.7, 55.8.
4.2. Typical procedure diarylation of sulfur or selenium
(Table 2)
A mixture of sulfur S8 (6.4 mg, 0.025 mmol), phenylboronic acid
(61.0 mg, 0.5 mmol), CuI (3.8 mg, 0.02 mmol), Phen･H2O (4.0
mg, 0.02 mmol) and NH4BF4 (5.2 mg, 0.05 mmol) in DMSO (0.2
mL), H2O (0.1 mL) was stirred at 100 °C for 18 h in air. After the
residue was dissolved in Et2O, the solution was washed with H2O
and saturated sodium chloride and dried over anhydrous
magnesium sulfate. Chromatography on silica gel (hexane) gave
diphenyl sulfide 3a (29.8 mg, 80%)2a, 6 as colorless oil; [Found:
C, 77.18; H, 5.49. C12H10S requires C, 77.37; H, 5.41%]; nmax
(neat) 3058, 1580, 1475, 1439 cm-1; 1H NMR (270 MHz, CDCl3)
δ 7.36–7.23 (m, 10H); 13C NMR (67.5 MHz, CDCl3) δ 135.7,
131.0, 129.2, 127.0.
4.2.8. Di(2-chlorophenyl) sulfide (3i)
The title compound was obtained as white solid (43.4 mg, 85%);
mp 67.5−68.0 °C; [Found: C, 56.70; H, 3.26. C12H8SCl2 requires
C, 56.48; H, 3.16%]; nmax (CHCl3) 3064, 1575, 1451, 1432 cm-1;
1H NMR (270 MHz, CDCl3) δ 7.47−7.44 (m, 2H), 7.26−7.11 (m,
6H); 13C NMR (67.5 MHz, CDCl3) δ 135.4, 133.2, 132.4, 130.1,
128.7, 127.5.
4.2.9. Di(2-formylphenyl) sulfide (3j)
The title compound was obtained as white solid (35.1 mg, 73%);
mp 92.0−93.5 °C; [Found: C, 69.04; H, 4.11. C14H10O2S requires
C, 69.40; H, 4.16%]; nmax (CHCl3) 2976, 1695, 1587, 1215 cm-1;
1H NMR (270 MHz, CDCl3) δ 10.37 (s, 2H), 7.99−7.95 (m, 2H),
4.2.1. Di(4-methylphenyl) sulfide (3b)

ACCEPTED MANUSCRIPT
6
Tetrahedron
7.54−7.44 (m, 4H), 7.20−7.17 (m, 2H); 13C NMR (67.5 MHz,
The title compound was obtained as white solid (19.5 mg, 34%);
mp 119.0−121.5 °C; [Found: C, 58.18; H, 3.52. C14H10O2Se
requires C, 58.15; H, 3.49%]; nmax (CHCl3) 2976, 1694, 1583,
1456 cm-1; 1H NMR (270 MHz, CDCl3) δ 10.28 (s, 2H),
7.99−7.96 (m, 2H), 7.52−7.43 (m, 4H), 7.31−7.26 (m, 2H); 13C
NMR (67.5 MHz, CDCl3) δ 193.2, 135.8, 135.6, 134.7, 134.4,
132.5, 128.0.
CDCl3) δ 191.6, 138.6, 135.0, 134.7, 132.5, 131.8, 127.9.
6
4.2.10. Di(1-naphtyl) sulfide (3k)
The title compound was obtained as white solid (40.2 mg, 70%);
mp 97.5−99.8 °C; [Found: C, 83.69; H, 5.24. C20H14S requires C,
83.88; H, 4.93%]; nmax (CHCl3) 3057, 1504, 1381 cm-1; 1H NMR
(270 MHz, CDCl3) δ 8.43−8.39 (m, 2H), 7.89−7.85 (m, 2H),
7.78−7.74 (m, 2H), 7.55−7.49 (m, 4H) , 7.32−7.22 (m, 4H); 13C
NMR (67.5 MHz, CDCl3) δ 134.1, 132.6, 132.4, 129.9, 128.6,
128.0, 126.7, 126.4, 125.8, 125.1.
4.2.19. Di(1-naphtyl) selenide (3k’)
The title compound was obtained as white solid (40.0 mg, 60%);
mp 90.9−91.5 °C; [Found: C, 71.88; H, 4.46. C20H14Se requires
C, 72.07; H, 4.23%]; nmax (CHCl3) 3056, 1560, 1502, 1378 cm-1;
1H NMR (270 MHz, CDCl3) δ 8.35−8.31 (m, 2H), 7.81−7.75 (m,
4H), 7.52−7.46 (m, 4H) , 7.28−7.22 (m, 4H); 13C NMR (67.5
MHz, CDCl3) δ 134.1, 133.6, 132.2, 129.8, 128.6, 128.4, 127.1,
126.8, 126.3, 126.1.
4.2.11. Diphenyl selenide (3a’)2 f ,
3 f
The title compound was obtained as colorlrss oil (35.0 mg, 67%);
[Found: C, 61.77; H, 4.35. C12H10Se requires C, 61.81; H,
4.32%]; nmax (CHCl3) 3070, 3056, 1575, 1475, 1437 cm-1; H
1
NMR (270 MHz, CDCl3) δ 7.48–7.44 (m, 6H), 7.28–7.24 (m,
4H); 13C NMR (67.5 MHz, CDCl3) δ 133.0, 129.3, 127.3.
4.3. Typical procedure of diarylation of tellurium (Table 4)
4.2.12. Di(4-methylphenyl) selenide (3b’)1 8
A mixture of tellurium (25.5 mg, 0.2 mmol), phenylboronic
acid (60.7 mg, 0.5 mmol), PdCl2 (3.5 mg, 0.02 mmol), Phen･H2O
(4.0 mg, 0.02 mmol) and KI (33.2 mg, 0.2 mmol) in DMSO (0.2
mL), H2O (0.1 mL) was stirred at 100 °C for 18 h in air. After the
residue was dissolved in Et2O, the solution was washed with H2O
and saturated sodium chloride and dried over anhydrous
magnesium sulfate. Chromatography on silica gel (hexane) gave
diphenyl telluride 4a (41.6 mg, 74%)22 as colorless oil; [Found:
C, 51.34; H, 3.49. C12H10Te requires C, 51.14; H, 3.58%]; nmax
(CHCl3) 3065, 1572, 1473, 1433 cm-1; 1H NMR (270 MHz,
CDCl3) δ 7.71–7.67 (m, 4H), 7.28–7.17 (m, 6H); 13C NMR (67.5
MHz, CDCl3) δ 138.0, 129.5, 127.8, 114.6.
The title compound was obtained as white solid (35.0 mg, 67%);
mp 62.0−64.1 °C; [Found: C, 64.40; H, 5.46. C14H14O2Se
requires C, 64.37; H, 5.40%]; nmax (CHCl3) 2977, 1520, 1489 cm-
1; 1H NMR (270 MHz, CDCl3) δ 7.35 (d, J = 8.2 Hz, 4H), 7.06 (d,
J = 8.2 Hz, 4H), 2.31 (s, 6H); 13C NMR (67.5 MHz, CDCl3) δ
137.1, 133.0, 139.1, 127.7, 21.1.
4.2.13. Di(4-methoxyphenyl) selenide (3c’)1 8
The title compound was obtained as white solid (42.5 mg, 73%);
mp 55.0−55.6 °C; [Found: C, 57.60; H, 4.78. C14H14O2Se
requires C, 57.35; H, 4.81%]; nmax (CHCl3) 2974, 1591, 1490,
1
1245 cm-1; H NMR (270 MHz, CDCl3) δ 7.40 (d, J = 8.9 Hz,
2 2
4H), 6.81 (d, J = 8.9 Hz, 4H), 3.77 (s, 6H); 13C NMR (67.5 MHz,
CDCl3) δ 159.2, 134.6, 122.1, 114.9, 55.3.
4.3.1. Di(4-methylphenyl) telluride (4b)
The title compound was obtained as white solid (37.3 mg, 60%);
mp 63.6−64.0 °C; [Found: C, 54.10; H, 4.46. C14H14Te requires
C, 54.27; H, 4.55%]; nma (CHCl3) 2977, 2923, 1486, 1391 cm-1;
1H NMR (270 MHz, CDCl3) δ 7.58 (d, J = 7.9 Hz, 4H), 7.02 (d, J
= 7.9 Hz, 4H), 2.32 (s, 6H); 13C NMR (67.5 MHz, CDCl3) δ
138.0, 137.7, 130.3, 110.7, 21.2.
4.2.14. Di(4-chlorophenyl) selenide (3d’)1 9
The title compound was obtained as white solid (44.7 mg, 74%);
mp 87.8−88.2 °C; [Found: C, 48.05, H, 2.72. C12H8Cl2Se requires
C, 47.72; H, 2.67%]; nmax (CHCl3) 2976, 1521, 1474 cm-1; H
1
NMR (270 MHz, CDCl3) δ 7.39−7.35 (m, 4H), 7.27−7.22 (m,
4H); 13C NMR (67.5 MHz, CDCl3) δ 134.3, 133.9, 129.6, 129.0.
4.3.2. Di(4-methoxyphenyl) telluride (4c)
The title compound was obtained as white solid (41.7 mg, 62%);
mp 51.8−52.5 °C; [Found: C, 48.94; H, 4.00. C14H14O2Te
requires C, 49.19; H, 4.13%]; nma (CHCl3) 2960, 2940, 2837,
1586, 1488, 1283, 1244 cm-1; 1H NMR (270 MHz, CDCl3) δ 7.62
(d, J = 8.9 Hz, 4H), 6.76 (d, J = 8.9 Hz, 4H), 3.76 (s, 6H); 13C
NMR (67.5 MHz, CDCl3) δ 159.6, 139.7, 115.3, 104.3, 55.1.
4.2.15. Di(4-methylcorboxylphenyl) selenide (3f’)
The title compound was obtained as white solid (50.0 mg, 72%);
mp 104.5−105.1 °C; [Found: C, 55.35; H, 4.09. C16H14O4Se
requires C, 55.03; H, 4.04%]; nmax (CHCl3) 1717, 1590, 1436,
1
1287 cm-1; H NMR (270 MHz, CDCl3) δ 7.94 (d, J = 8.6 Hz,
4H), 7.51 (d, J = 8.6 Hz, 4H), 3.91 (s, 6H); 13C NMR (67.5 MHz,
CDCl3) δ 166.6, 136.9, 132.5, 130.4, 129.3, 52.2.
4.3.3. Di(4-bromophenyl) telluride (4l)
The title compound was obtained as white solid (57.0 mg, 65%);
4.2.16. Di(2-methylphenyl) selenide (3g’)2 0
The title compound was obtained as white solid (40.6 mg, 78%);
mp 95.5−96.0 °C; [Found: C, 32.89; H, 1.86. C12H8Br2Te
1
requires C, 32.79; H, 1.83%]; nma (CHCl3) 1471, 1382 cm-1; H
mp 58.0−60.5 °C; [Found: C, 64.40; H, 5.46. C14H14Se requires
NMR (270 MHz, CDCl3) δ 7.54−7.49 (m, 4H), 7.36−7.25 (m,
C, 64.37; H, 5.40%]; nmax (CHCl3) 3016, 1590, 1466 cm-1; H
1
4H); 13C NMR (67.5 MHz, CDCl3) δ 139.6, 132.8, 122.9, 112.7.
NMR (270 MHz, CDCl3) δ 7.25−7.16 (m, 6H), 7.07−7.01 (m,
2H), 2.40 (s, 6H); 13C NMR (67.5 MHz, CDCl3) δ 139.8, 133.2,
131.3, 130.2, 127.6, 126.8, 22.2.
4.3.4. Di(4-chlorophenyl) telluride (4d)
The title compound was obtained as white solid (52.4 mg, 75%);
mp 119.8−120.0 °C; [Found: C, 41.06; H, 2.22. C12H8Cl2Te
requires C, 41.10; H, 2.30%]; nma (CHCl3) 1472, 1377 cm-1; H
1
4.2.17. Di(2-methoxyphenyl) selenide (3h’)
The title compound was obtained as white solid (48.9 mg, 83%);
mp 56.6−58.8 °C; [Found: C, 57.36; H, 4.93. C14H14O2Se
requires C, 57.35; H, 4.81%]; nmax (CHCl3) 3007, 2836, 1578,
NMR (270 MHz, CDCl3) δ 7.61−7.58 (m, 4H), 7.25−7.16 (m,
4H); dC (67.5 MHz, CDCl3) δ 139.3, 134.6, 129.9, 112.0.
1
1474, 1432 cm-1; H NMR (270 MHz, CDCl3) δ 7.30−7.23 (m,
4.3.5. Di(4-formylphenyl) telluride (4e)
2H), 7.18−7.15 (m, 2H), 6.91−6.81 (m, 4H), 3.86 (s, 6H); 13C
NMR (67.5 MHz, CDCl3) δ 158.2, 133.7, 128.7, 118.9, 110.6,
55.9.
The title compound was obtained as yellow solid (38.7 mg,
57%); mp 113.1−115.0 °C; [Found: C, 49.68; H, 2.93.
C14H10O2Te requires C, 49.77; H, 2.98%]; nma (CHCl3) 1701,
1
1582, 1380 cm-1; H NMR (270 MHz, CDCl3) δ 9.98 (s, 2H),
7.85−7.82 (m, 4H), 7.75−7.71 (m, 4H); 13C NMR (67.5 MHz,
CDCl3) δ 191.6, 138.0, 135.9, 130.3, 123.8.
4.2.18. Di(2-formylphenyl) selenide (3j’)

ACCEPTED MANUSCRIPT
7
4. Kulka, M. Can. J. Chem. 1956, 34, 1093−1100.
4.3.6. Di(4-methylcorboxylphenyl) telluride (4f)
5. Selected report for the synthesis of diaryl chalcogenides: (a) Rábai,
J. Synthesis 1989, 523−551. (b) Syper, L.; Młochowski, J.
Tetrahedron 1988, 44, 6119−6130. (c) Detty, M. R.; Seidler, M. D.
J. Org. Chem. 1982, 47, 1354−1356. (d) Ke, F.; Qu, Y.; Jiang, Z.;
Li, Z.; Wu,D.; Zhou, X. Org. Lett. 2011, 13, 454−457. (e) Alves,
D.; Pena, J. M.; Vieira, A. S.; Botteselle, G. V.; Guadagnin, R. C.;
Stefani, H. A. J. Braz. Chem. Soc. 2009, 20, 988−992. Dialkyl
chalcogenides: (f) Gladysz, J. A.; Wong, V. K.; Jick, B. S.
Tetrahedron 1979, 35, 2329−2335. (g) Hase, T. A.; Peräkylä, H.
Synth. Commun. 1982, 12, 947−950. (h) Li, J. Q.; Bao, W. L.; Lue.
P.; Zhou, X.-J. Synth. Commun. 1991, 21, 799−806. (i) Ham, J.;
Yang, J.; Kang, H. J. Org. Chem. 2004, 69, 3226−3239. (j)
Miyazaki, T.; Katayama, M.; Yoshimoto, S.; Ogiwara, Y.; Sakai,
N. Tetrahedron Lett. 2016, 57, 676−679. (k) Singh, D.; Deobald,
A. M.; Camargo, L. R. S.; Tabarelli, G.; Rodrigues, O. E. D.;
Braga, A. L. Org. Lett. 2010, 12, 3288−3291. Intramolecular
compounds: (l) Balkrishna, S. J.; Bhakuni, B. S.; Chopra, D.;
Kumar, S. Org. Lett. 2010, 12, 5394−5397. (m) Deng, H.; Li, Z.;
Ke, F.; Zhou, X. Chem. Eur. J. 2012, 18, 4840−4843.
The title compound was obtained as white solid (56.9 mg, 72%);
mp 91.2−92.0 °C; [Found: C, 48.28; H, 3.42. C16H14O4Te
requires C, 48.30; H, 3.55%]; nma (CHCl3) 1720, 1586, 1436,
1
1284 cm-1; H NMR (270 MHz, CDCl3) δ 7.87 (d, J = 8.5 Hz,
4H), 7.73 (d, J = 8.5 Hz, 4H), 3.91 (s, 6H); 13C NMR (67.5 MHz,
CDCl3) δ 166.7, 137.5, 130.4, 129.8, 121.4, 52.2.
2 2
4.3.7. Di(1-naphtyl) telluride (4k)
The title compound was obtained as white solid (58.9 mg, 77%);
mp 106.5−107.0 °C; [Found: C, 62.58; H, 3.64. C20H14Te
requires C, 62.90; H, 3.69%]; nma (CHCl3) 3053, 1555, 1500 cm-
1; 1H NMR (270 MHz, CDCl3) δ 8.17−8.13 (m, 2H), 7.80−7.77
(m, 6H), 7.51−7.45 (m, 4H) , 7.21−7.15 (m, 2H); 13C NMR (67.5
MHz, CDCl3) δ 138.0, 135.8, 133.8, 131.2, 129.2, 128.8, 127.0,
126.6, 126.3, 117.5.
Supplementary data
6. (a) Jiang, Y.; Quin, Y.; Xie, S.; Zhang, X.; Dong, J.; Ma, D. Org.
Lett. 2009, 11, 5250−5253. (b) Rostami, A.; Rostami, A.; Ghaderi,
A. J. Org. Chem. 2015, 80, 8694−8704.
Supplementary data related to this article can be found at
http://xxxxxxxxxxx
7. (a) Taniguchi, N. Tetrahedron 2012, 68, 10510−10515. (b)
Taniguchi, N. Synlett 2005, 1687−1690.
8. Yu, J.-T.; Guo, H.; Yi, Y.; Fei, H.; Jiang, Y. Adv. Synth.Catal.
2014, 356, 749−752.
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