Convenient synthesis of unsymmetrical organochalcogenides using organoboronic acids with dichalcogenides via cleavage of the S-S, Se-Se, or Te-Te bond by a copper catalyst

Article abstract of DOI:10.1021/jo062131+

(Chemical Equation Presented) This article describes the methodology for a copper-catalyzed preparation of numerous monochalcogenides from dichalcogenides with organoboronic acids. Unsymmetrical diorgano-monosulfides, selenides, and tellurides can be synthesized by the coupling of dichalcogenides with aryl- or alkylboronic acids using a copper catalyst in air. The present reaction can take advantage of both organochalcogenide groups on dichalcogenide.

Full text of DOI:10.1021/jo062131+

Convenient Synthesis of Unsymmetrical Organochalcogenides Using
Organoboronic Acids with Dichalcogenides via Cleavage of the S-S,
Se-Se, or Te-Te Bond by a Copper Catalyst
Nobukazu Taniguchi*
Department of Chemistry, Fukushima Medical UniVersity, Fukushima 960-1295, Japan
taniguti@fmu.ac.jp
ReceiVed October 15, 2006
This article describes the methodology for a copper-catalyzed preparation of numerous monochalcogenides
from dichalcogenides with organoboronic acids. Unsymmetrical diorgano-monosulfides, selenides, and
tellurides can be synthesized by the coupling of dichalcogenides with aryl- or alkylboronic acids using
a copper catalyst in air. The present reaction can take advantage of both organochalcogenide groups on
dichalcogenide.
Introduction
thiol or selenol is usually employed under basic conditions.
However, the synthesis using dichalcogenide has been limited
Organochalcogenides have found widespread utilization as
convenient intermediates or reagents in organic syntheses. To
synthesize these compounds, various procedures have been
explored so far. Especially, transition metal-catalyzed aryl
carbon-chalcogen bond formation is an important method for
the preparation of unsymmetrical organochalcogenides and is
studied by many researchers.3
7,8
to a reaction using alkyl halides; nevertheless, dichalcogenides
are easy to treat and are stable compounds in air. As a general
rule, in the metal-catalyzed chalcogenylation of aryl halides
using dichalcogenide, a reductant is necessary for the generation
1
2
9
of a corresponding anion or a metal-monochalcogenide
1
0,11
complex.
On the contrary, the transition metal-catalyzed preparation
of monosulfide from disulfide and organoboronic acid under
oxidative conditions has been rarely developed, despite the fact
4
For the preparation of aryl chalcogenides using a palladium,
5
6
nickel, or copper catalyst, a combination of aryl halide with
*
Corresponding author. Tel.: 81-24-547-1369. Fax: 81-24-547-1369.
(4) For selected paper for the method using Pd catalyst: (a) Kosugi,
M.; Shimizu, T.; Migita, T. Chem. Lett. 1978, 13-14. (b) Migita, T.;
Shimizu, T.; Asami, Y.; Shiobara, J.; Kosugi, M. Bull Chem. Soc. Jpn.
1980, 53, 1385-1389. (c) Cristau, H. J.; Chabaud, B.; Christol, C. H.
Synthesis 1981, 892-894. (d) Kosugi, M.; Ogata, T.; Terada, M.; Sano,
H.; Migita, T. Bull. Chem. Soc. Jpn. 1985, 58, 3657-3658. (e) Hartwig, J.
F.; Barra n˜ ano, D. J. Am. Chem. Soc. 1995, 117, 2937-2938. (f) Ciattini,
P. G.; Morera, E.; Ortar, G. Tetrahedron Lett. 1995, 36, 4133-4136. (g)
Zheng, N.; McWilliams, J. C.; Fleitz, F. J.; Armstrong, J. D., III; Volante,
R. P. J. Org. Chem. 1998, 63, 9606-9607. (h) Nishiyama, Y.; Tokunaga,
K.; Sonoda, N. Org. Lett. 1999, 1, 1725-1727. (i) Itoh, T.; Mase, T. Org.
Lett. 2004, 6, 4587-4590.
(5) The method using Ni catalyst: (a) Cristau, H. J.; Chabaud, B.; Ch eˆ ne,
A.; Christol, H. Synthesis 1981, 892-894. (b) Yamamoto, T.; Sekine, Y.
Can. J. Chem. 1984, 62, 1544-1547. (c) Takagi, K. Chem. Lett. 1985,
1307-1308. (d) Takagi, K. Chem. Lett. 1987, 2221-2224.
(6) The method using Cu catalyst: (a) Suzuki, H.; Abe, H.; Osuka, A.
Chem. Lett. 1980, 1363-1364. (b) Suzuki, H.; Abe, H.; Osuka, A. Chem.
Lett. 1981, 151-152. (c) Bowman, W. R.; Heaney, H.; Smith, P. H. G.
Tetrahedron Lett. 1984, 25, 5821-5824. (d) Kwong, F. Y.; Buchwald, S.
L. Org. Lett. 2002, 4, 3517-3520. (e) Gujadhur, R. K.; Venkataruman, D.
Tetrahedron Lett. 2003, 44, 81-84.
(1) For selected reviews: (a) Metzner, P.; Thuillier, A. Sulfur Reagents
in Organic Synthesis; Katritzky, A. R., Meth-Cohn, O., Rees, C. W., Eds.;
Academic Press: San Diego, 1994. (b) ComprehensiVe Organic Synthesis;
Trost, B. M., Fleming, I., Eds.; Pergamon Press Ltd.: New York, 1991;
Vol. 6. (c) Paulmier, C. In Selenium Reagents and Intermediates in Organic
Synthesis, Organic Chemistry Series 4; Baldwin, J. E., Ed.; Pergamon Press
Ltd.: Oxford, 1986. (d) Wirth, T., Ed. Organoselenium Chemistry; Topics
in Current Chemistry 208; Springer-Verlag: Heidelberg; 2000. (e) Petrag-
nani, N. Tellurium in Organic Synthesis; Katritzky, A. R., Meth-Cohn, O.,
Rees, C. W., Eds.; Academic Press: San Diego, 1994. (f) Comasseto, J.
V.; Barientos-Astigarraga, R. E. Aldrichim. Acta 2000, 33, 66-78.
(
2) For selected reviews: (a) ComprehensiVe Organic Synthesis; Trost,
B. M., Fleming, I., Eds.; Pergamon Press Ltd.: New York, 1991; Vol. 4.
b) Krief, A. In ComprehensiVe Organometallic Chemistry II; Abel, E. W.,
Stone, F. G. A., Wilkinson, G., Eds.; Pergamon Press Ltd.: New York,
995; Vol. 11, Ch. 13. (c) Miyaura, N. In Metal-Catalyzed Cross-Coupling
(
1
Reactions; Meijere, A., Diederich, F., Eds.; Wiley-VCH: Weinheim, 2004;
Vol. 1, pp 41-123.
(3) For selected reviews: (a) Ley, S. V.; Thomas, A. W. Angew. Chem.,
Int. Ed. 2003, 42, 5400-5449. (b) Kondo, T.; Mitsudo, T. Chem. ReV. 2000,
00, 3205-3220.
1
1
0.1021/jo062131+ CCC: $37.00 © 2007 American Chemical Society
Published on Web 01/17/2007
J. Org. Chem. 2007, 72, 1241-1245
1241

Taniguchi
SCHEME 1. Reaction of Disulfides with Organoboronic
Acids by CuX
TABLE 1. Copper-Catalyzed Coupling of (4-MeC6H4S)2 with
PhB(OH)2
entry
solvent
3 (%)a,b
1 (%)a
1c
2
PhCH3
DMF
DMSO
DMSO
DMSO
45
82
97
76
18
46
13
0
10
79
that a reaction using a stoichiometric copper(II) salt with thiol12
or, recently, a copper-catalyzed reaction using other dichalco-
genides having high reactivity has been reported.13 The cause
is attributed to the lower activity of the generated metal-sulfide
complex as an intermediate. Therefore, in the catalytic synthesis
of organosulfides using organoboronic acids, a method employ-
3
c
4
d
5
a
Isolated yields after silica-gel chromatography. b Yields of 3 are based
on disulfide 1 (2 mol). c H2O was not added. d bpy was not used.
1
4
ing thioimide as a sulfur source has been explored.
To accelerate the catalytic cycle using disulfide, after oxida-
When a mixture of (4-MeC6H4S)2 1 (0.2 mmol), phenylbo-
ronic acid 2 (0.6 mmol), and CuI-bpy (5 mol %) in toluene
0.3 mL) was treated at 100 °C, phenyl 4-tolyl sulfide 3 was
obtained in only 45% yield (Table 1, entry 1). The reaction in
DMF/H2O could give 3 in 82% yield with the recovery of 1 in
1
2
tion of CuSR, a reaction of the obtained complex with R B-
OH)2 should produce the corresponding sulfide (Scheme 1).
(
(
Consequently, the present process requires an oxidant. As a
procedure to carry out the reaction, we examined conditions in
air and found that unsymmetrical monosulfides could be
1
3% yield (Table 1, entry 2). Other solvents (1,3-dimethyl-2-
imidazolidinone and dioxane) also showed the same result.
However, these conditions could not be used because a small
amount of 1 was recovered, and the separation of 1 and 3 was
very complicated.
Fortunately, the system of DMSO/H2O (0.2 mL/0.1 mL)
could afford 3 in 97% yield with complete consumption of 1
synthesized from disulfide and organoboronic acid by a copper
catalyst at 100 °C in a DMSO-H2O solvent.15
In this paper, we wish to describe the synthesis of unsym-
metrical monochalcogenides (sulfides, selenides, or tellurides)
from dichalcogenides with organoboronic acids by a copper
catalyst.
1
6
(
Table 1, entry 3). The absence of a bpy ligand decreased the
production of 3 (Table 1, entry 5), and other ligands (TMEDA
Results and Discussion
1
7
and PPh3) did not work effectively. The present system could
also use other copper catalysts (CuCl, CuBr, CuOAc, CuCl2,
and CuBr2), although the use of Cu(OAc)2 decreased the yield
slightly.
Application to the Copper-Catalyzed Preparation of
Diorganosulfides, Selenides, or Tellurides Using Dichalco-
genides with Organoboronic Acids. On the basis of the
previously described experimental results, we next examined a
CuI-catalyzed aryl- or alkylation of disulfide by the use of
organoboronic acid in DMSO-H2O (Table 2).
Preparation of Monosulfide from Disulfide and Phenyl-
boronic Acid. Initially, to carry out copper-catalyzed coupling
of dichalcogendie with organoboronic acid, the reaction with
disulfide was investigated.
(7) Chalcogenations of alkyl halides or alkenyl borane with dichalco-
genide are known. See: (a) Chowdhury, S.; Roy, S. Tetrahedron Lett. 1997,
3
8, 2149-2152. (b) Kundu, A.; Roy, S. Organometallics 2000, 19, 105-
1
07. (c) Nishino, T.; Okada, M.; Kuroki, T.; Watanabe, T.; Nishiyama, Y.;
Sonoda, N. J. Org. Chem. 2002, 67, 8696-8698. (d) Nishino, T.; Nishiyama,
Y.; Sonoda, N. Chem. Lett. 2003, 928-929. (e) Ranu, B. C. Mandal, T. J.
Org. Chem. 2004, 69, 5793-5795. (f) Ajiki, K.; Tanaka, K. Org. Lett. 2005,
At first, various organoboronic acids (0.6 mmol) and diphenyl
disulfide (0.2 mmol) were treated with CuI-bpy (5 mol %) at
7
1
, 4193-4195. (g) Huang, X.; Liang, C.-G. J. Chem. Soc., Perkin Trans 1
999, 2625-2626.
1
00 °C in air, to afford expected sulfides 6 in good yields. The
(
8) A reaction of disulfide with RMgX or RLi can also give a
present reactions could afford 6 in good yields without the
influence of the para-substituted groups. In the use of ortho-
substituted arylboronic acid, the reactivity decreased owing to
steric hindrance (Table 2, entries 3 and 4). Furthermore, this
procedure could tolerate alkenyl- or alkylboronic acids, but the
employment of alkylboronic acid required longer reaction times
than the reaction of arylboronic acids (Table 2, entries 12-
16).
The combination of diaryl disulfides with phenylboronic acids
could also afford the corresponding products (Table 2, entries
17-24). However, the reactivity was dependent on substrates.
Unfortunately, the reaction of di-n-butyl disulfide proceeded in
low yield (Table 2, entry 25).
corresponding monosulfide. But, this case cannot use one sulfide group on
disulfide. See: Negishi, E., Ed. Organometallics in Organic Synthesis;
Wiley: New York, 1980.
(
9) Millois, C.; Diaz, P. Org. Lett. 2000, 2, 1705-1708.
(
10) (a) Taniguchi, N.; Onami, T. Synlett 2003, 829-832. (b) Taniguchi,
N.; Onami, T. J. Org. Chem. 2004, 69, 915-920. (c) Taniguchi, N. J. Org.
Chem. 2004, 69, 6904-6906. (d) Taniguchi, N. Synlett 2005, 1687-1690.
(
e) G o´ mez-Betez, V.; Baldovino-Pantale o´ n, O.; Herrera- AÄ lvarez, C.;
Toscano, R. A.; Morales-Morales, D. Tetrahedron Lett. 2006, 47, 5059-
5
062. (f) Kumar, S.; Engman, L. J. Org. Chem. 2006, 71, 5400-5403. (g)
Chang, D.; Bao, W. Synlett 2006, 1786-1788. (h) Fukuzawa, S.-i.; Tanihara,
D.; Kikuchi, S. Synlett 2006, 2145-2147.
(11) Transition metals can be inserted into dichalcogenide bonds: (a)
Zanella, R.; Ros, R.; Graziani, M. Inorg. Chem. 1973, 12, 2736-2738. (b)
Lam, C. T.; Senoff, C. V. Can. J. Chem. 1973, 51, 3790-3794. (c) Canich,
J. A. M.; Cotton, F. A.; Dunbar, K. R.; Falvello, L. R. Inorg. Chem. 1988,
2
7, 804-811.
(
12) Herradura, P. S.; Pendola, K. A.; Guy, R. K. Org. Lett. 2000, 2,
(16) In transition metal-catalyzed organic reactions using organoboronic
acids, water has been added: (a) Miyaura, N.; Suzuki, A. Chem. ReV. 1995,
95, 2457-2483. (b) Hayashi, T.; Yamasaki, K. Chem. ReV. 2003, 103,
2829-2844.
(17) When TMEDA and PPh3 as a ligand were employed, the yields
were 58 and 4%, respectively.
2
019-2022.
(
13) Wang, L.; Wang, M.; Huang, F. Synlett 2005, 2007-2010.
(14) Savarin, C.; Srogl, J.; Liebeskind, L. S. Org. Lett. 2002, 4, 4309-
4
312.
(15) Taniguchi, N. Synlett 2006, 1351-1354.
1242 J. Org. Chem., Vol. 72, No. 4, 2007

Synthesis of Unsymmetrical Organochalcogenides
TABLE 2. CuI-Catalyzed Coupling of Disulfides with Organoboronic Acidsa
entry
R1
Ph
R2
time (h)
6 (%)b,c
entry
R1
R2
time (h)
6 (%)b,c
1
2
3
Ph
12
12
24
24
12
12
12
12
12
12
12
30
97
97
50
76
97
98
88
96
90
98
89
97
13
14
15
Ph
Me
12
42
48
48
12
48
12
24
12
24
42
42
24
93
72
94
65
97
74
67
66
97
65
72
25
29
2-MeC6H4
2-MeOC6H4
2-ClC6H4
4-MeC6H4
4-MeOC6H4
4-BrC6H4
n-Bu
e
cyclo-C6H11
PhCH2CH2
Ph
e
e
4
16
5
6
7
8
9
17
18
19
20
21
4-MeC6H4
4-MeOC6H4
4-BrC6H4
4-ClC6H4
4-O2NC6H4
4-H2NC6H4
4-HO2CC6H4
4-HOC6H4
n-Bu
4-ClC6H4
4-HOC6H4
4-OHCC6H4
4-MeO2CC6H4
(E)sPhCHdCH
d
1
1
1
0
1
2
22
23
24
e
25
a
Reaction conditions: the mixture of 4 (0.2 mmol), 5 (0.6 mmol), and CuI-bpy (1:1, 5 mol %) in DMSO (0.2 mL) and H2O (0.1 mL) was treated at 100
c
e
°
C. b Isolated yields after silica-gel chromatography. Yields of 6 are based on disulfide 4 (2 mol). d This reaction was carried out at 90 °C. 10 mol
%CuI-bpy was used.
TABLE 3. CuI-Catalyzed Coupling of Diselenides or Ditellurides with Organoboronic Acidsa
1
R2
8 (%)b,c
1
R2
8 (%)b,c
entry
(R Y)2
time (h)
entry
(R Y)2
time (h)
1
2
3
4
5
6
7
8
9
(PhSe)2
Ph
12
12
12
12
12
12
12
12
12
12
12
12
12
38
93
99
96
93
98
93
83
95
80
96
95
89
86
63
15
16
17
18
19
20
21
22
23
24
25
26
27
28
(BnSe)2
(PhTe)2
Ph
Ph
24
4
4
12
4
4
12
4
4
12
12
12
4
84
87
79
75
95
81
97
90
85
79
88
86
71
38
2-MeC6H4
2-MeOC6H4
2-ClC6H4
4-MeC6H4
4-MeOC6H4
4-BrC6H4
4-ClC6H4
4-HOC6H4
4-OHCC6H4
4-MeO2CC6H4
(E)sPhCHdCH
Me
2-MeC6H4
2-MeOC6H4
2-ClC6H4
4-MeC6H4
4-MeOC6H4
4-BrC6H4
4-ClC6H4
1
1
1
1
1
0
1
2
3
4
4-HOC6H4
4-OHCC6H4
4-MeO2CC6H4
(E)sPhCHdCH
n-Bu
d
n-Bu
18
a
Reaction conditions: the mixture of 7 (0.2 mmol), 5 (0.6 mmol), and CuI-bpy (1:1, 5 mol %) in DMSO (0.2 mL) and H2O (0.1 mL) was treated at 100
c
°
C. b Isolated yields after silica-gel chromatography. Yields of 8 are based on dichalcogenide 7 (2 mol). d 10 mol % CuI was used.
SCHEME 2. Reaction of (PhS)
the Absence of Oxygen
2 6 4 2
with 4-MeC H B(OH) in
Thus, the coupling of diaryl disulfides with organoboronic
acids by a copper catalyst could furnish the desired sulfides in
good yields and was able to use both sulfide groups on disulfide.
Then, we explored the reaction using other dichalcogenides.
According to the previously developed procedure, the copper-
catalyzed coupling of diselenides or ditellurides with organobo-
ronic acids was carried out (Table 3).
As expected, various unsymmetrical monochalcogenides 8
were obtained in good yields, and the present reaction was not
affected by substrates. In the reaction using ditelluride, the
monotellurides were obtained in very short time. However, the
yield of butyl phenyl telluride decreased (Table 3, entry 28).
Proposed Reaction Mechanism of the Copper-Catalyzed
Coupling of Disulfides with Organoboronic Acids. For the
purpose of investigation of the reaction mechanism, we initially
examined a reaction in the absence of oxygen. When the CuI-
or CuCl2-catalyzed reaction of (PhS)2 with 4-MeC6H4B(OH)2
was carried out, the corresponding sulfide 3 was obtained in
only 7% production or 3% (Scheme 2).
Also, the reactivity of PhSCu considered as an intermediate
1
8
was examined. When a reaction of PhSCu and 4-MeC6H4B-
OH)2 was performed in DMSO-H2O, the corresponding sulfide
was obtained in 53% yield (Scheme 3). Moreover, the
(
3
(18) For the preparation of PhSCu: Adams, R., Reifschneider, W.,
Ferretti, A. Organic Synthesis; John Wiley & Sons: New York, 1973; Vol.
V, pp 107-110.
J. Org. Chem, Vol. 72, No. 4, 2007 1243

Taniguchi
(disulfides or organoboronic acids) or copper catalyst. In the
case of other chalcogenides, the same process can apply.
Conclusion
In conclusion, we were able to synthesize various unsym-
metrical organosulfides, selenides, and tellurides from dichal-
cogenides using organoboronic acids by a CuI-bpy catalyst in
DMSO-H2O. Furthermore, this procedure requires oxygen in
air as oxidant to promote the reaction and can tolerate aryl- or
alkylation of two chalcogenide groups on dichalcogenide.
FIGURE 1. Plausible reaction mechanism.
SCHEME 3. Reaction of PhSCu with 4-MeC
6
H
4
B(OH)
2
Experimental Section
General Procedure. All reactions were carried out in air. NMR
spectra were recorded on a JEOL EX-270 spectrometer (270 MHz
1
13
for H, 67.5 MHz for C). Chemical shifts are reported in δ ppm
1
referenced to an internal tetramethylsilane standard for H NMR
and chloroform-d (δ 77.0) for 13C NMR. IR spectra were measured
by a Spectrum One FT-IR spectrometer. Melting points were
measured on a Melting Point B-540 apparatus. Elemental analysis
was performed at the Instrumental Analysis Center for Chemistry,
Tohoku University (Japan).
Coupling of Disulfide with Organoboronic Acid (Table 2):
1
Entry 10. H NMR (270 MHz, CDCl
3
) δ 9.89 (s, 1H), 7.70 (d, J
production was increased to 68% yield in the presence of n-Bu4-
NI as the anion source of PhSCu(II) after the oxidation of
PhSCu(I).19
) 8.6 Hz, 2H), 7.49-7.53 (m, 2H), 7.43-7.39 (m, 3H), 7.23 (d, J
) 8.6 Hz, 2H); 13C NMR (67.5 MHz, CDCl
) δ 191.0, 147.1, 134.2,
133.6, 131.2, 130.0, 129.7, 129.0, 127.1; IR (neat) 3058, 1697, 1591,
3
-
1
1561, 1475 cm ; Anal. Calcd for C13
H10OS: C, 72.87; H, 4.70.
Thus, the coupling of disulfide with organoboronic acid
requires oxygen. This fact shows that PhSCu(I) can react with
organoboronic acid through a formation of PhSCu(II)X by the
oxidation of PhSCu(I) in the presence of oxygen.
From these results, a plausible reaction mechanism is
Found: C, 72.69; H, 4.95.
1
Entry 11. H NMR (270 MHz, CDCl
3
) δ 7.88 (d, J ) 8.6 Hz,
2
2
1
1
4
H), 7.49-7.45 (m, 2H), 7.39-7.35 (m, 3H), 7.20 (d, J ) 8.6 Hz,
H), 3.87 (s, 3H); 13C NMR (67.5 MHz, CDCl
) δ 166.5, 144.2,
33.6, 132.3, 130.0, 129.5, 128.5, 127.5, 127.4, 51.9; IR (CHCl
3
3
)
2
0
2
considered as follows (Figure 1). In cycle A, after R Cu(I)
1
-1
12 2
715, 1594, 1436 cm ; Anal. Calcd for C14H O S: C, 68.83; H,
2
0 is formed from R B(OH)2 with CuX, both the sulfide 12
.95. Found: C, 68.66; H, 5.10.
and the PhSCu(I)Ln 13 produced by the reaction of 10 react
1
Entry 16. H NMR (270 MHz, CDCl
3
) δ 7.37-7.14 (m, 10H),
1
1
2
with (R S)2. Sequentially, (R S)(R )Cu(II) 15 is formed via the
13
3
.19-3.12 (m, 2H), 2.95-2.88 (m, 2H); C NMR (67.5 MHz,
1
1
2
oxidation of R SCuLn 13. Finally, R SR 12 is produced again
through the oxidation of 15.
In cycle B, after the reaction of CuX with (R S)2, the sulfide
2 and R SCu(I)Ln 13 are produced from the generated copper-
disulfide complex 16 with R B(OH)2 9.
CDCl ) δ 140.2, 136.3, 129.2, 128.9, 128.5, 127.0, 126.4, 125.9,
3
-
1
35.6, 35.1; IR (neat) 3060, 3026, 2923, 1583, 1495, 1479 cm
;
1
Anal. Calcd for C H S: C, 78.45; H, 6.58. Found: C, 78.71; H
14 14
1
6.70.
1
1
2
21,22
Entry 22. mp 94-95 °C; H NMR (270 MHz, CDCl ) δ 7.30
3
(
d, J ) 8.2 Hz, 2H), 7.24-7.05 (m, 5H), 6.65 (d, J ) 8.4 Hz, 2H),
Similarly, it seems that in the case of the CuX2 catalyst,
complex 13 is formed via some processes after the generation
of a Cu(II)-disulfide complex by cleavage of disulfide at the
3
1
1
.78 (br, 2H); 13C NMR (67.5 MHz, CDCl
3
) δ 147.0, 139.6, 136.0,
) 3400, 1618, 1494,
H11NS: C, 71.60; H, 5.51. Found:
28.7, 127.2, 125.2, 120.4, 115.8; IR (CHCl
3
-
1
477 cm ; Anal. Calcd for C12
2
3
first step.
C, 71.30; H, 5.70.
Entry 23. mp 172-173 °C; H NMR (270 MHz, CDCl
d, J ) 8.5 Hz, 2H), 7.53-7.38 (m, 5H), 7.20 (d, J ) 8.5 Hz, 2H);
In addition, it is considered that the generating proportion of
these two processes is different according to the kind of substrate
1
3
) δ 7.95
(
1
3
C NMR (67.5 MHz, CDCl
129.7, 128.9, 127.1, 126.3; IR (CHCl
3
) δ 171.4, 146.0, 134.0, 131.8, 130.6,
-
1
(19) Other salts (KI and LiI) also gave the same results (63 and 68%,
) 3412, 1691, 1594 cm
;
3
respectively).
Anal. Calcd for C13
H, 4.20.
10 2
H O S: C, 67.80; H, 4.38. Found: C, 67.54;
(
20) (a) Evans, D. A.; Katz, J. L.; West, T. R. Tetrahedron Lett. 1998,
3
1
9, 2937-2940. (b) Collman, J. P.; Zhong, M. Org. Lett. 2000, 2, 1233-
Coupling of Diselenide with Organoboronic Acid (Table 3):
236. (c) Corbet, J.-P.; Mignani, G. Chem. ReV. 2006, 106, 2651-2710.
1
(21) A disulfide bond can be cleaved by Cu(I)X: (a) Kadooka, M. M.;
Entry 4. H NMR (CDCl
3
) δ 7.63-7.59 (m, 2H), 7.40-7.29 (m,
Warner, L. G.; Seff, K. J. Am. Chem. Soc. 1976, 98, 7569-7578. (b)
4H), 7.09 (dt, J ) 7.6 and 1.6 Hz, 1H), 7.01 (dt, J ) 7.6 and 1.3
Taniguchi, N. J. Org. Chem. 2006, 71, 7874-7876; see ref 9b,d.
13
Hz, 1H), 6.91 (dd, J ) 7.6 and 1.6 Hz, 1H); C NMR (CDCl
3
) δ
(
22) It is well known that a transition metal can cleave a disulfide bond:
1
36.0, 135.9, 133.8, 133.4, 130.5, 129.7, 129.3, 128.8, 127.8, 127.2;
(
a) Bewick, A.; Mellor, J. M.; Milano, D.; Owton, W. M. J. Chem. Soc.,
-
1
IR (neat) 3057, 1950, 1573, 1476, 1437 cm ; Anal. Calcd for
Perkin Trans, 1 1985, 1045-1048. (b) Bach, R. D.; Rajan, S. J.; Vardhan,
H. B.; Lang, T. J.; Albrecht, N. G. J. Am. Chem. Soc. 1981, 103, 7727-
C
12
H
9
SeCl: C, 53.86; H, 3.39. Found: C, 53.85; H, 3.56.
1
7
1
734. (c) Ichimura, A.; Nosco, D. L.; Deutsch, E. J. Am. Chem. Soc. 1983,
05, 844-850.
Entry 10. H NMR (270 MHz, CDCl
) δ 9.90 (s, 1H), 7.67 (d,
3
13
J ) 8.6 Hz, 2H), 7.59-7.62 (m, 2H), 7.41-7.34 (m, 5H); C NMR
67.5 MHz, CDCl ) δ 191.2, 142.6, 135.4, 134.4, 130.1, 130.0,
29.7, 128.8, 127.8; IR (neat) 3055, 2828, 2733, 1696, 1587 cm
(
23) Cu(I)-sulfide complex can be prepared by a reaction of disulfide
(
1
3
with Cu(II)-salt in air: (a) Odani, A.; Maruyama, T.; Yamaguchi, O.;
-1
;
Fujiwara, T.; Tomita, K.-i. J. Chem. Soc., Chem. Commun. 1982, 646-
647. (b) Higashi, L. S.; Lundeen, M.; Milti, E.; Seff, K. Inorg. Chem. 1977,
Anal. Calcd for C13H10OSe: C, 59.78; H, 3.86. Found: C, 59.55;
1
6, 310-313.
H, 3.96.
1244 J. Org. Chem., Vol. 72, No. 4, 2007

Synthesis of Unsymmetrical Organochalcogenides
1
13C NMR (67.5 MHz, CDCl
Entry 11. H NMR (CDCl
3
) δ 7.86 (d, J ) 8.6 Hz, 2H), 7.58-
3
) δ 139.2, 138.2, 132.5, 129.6, 128.1,
13
-1
7
.55 (m, 2H), 7.37-7.25 (m, 4H), 3.87 (s, 3H); C NMR (CDCl
δ 166.6, 139.5, 134.8, 130.3, 130.0, 129.6, 128.6, 128.4, 128.1,
2.0. IR (neat) 3020, 1718, 1591, 1436 cm-1; Anal. Calcd for
Se: C, 57.74; H, 4.15. Found: C, 57.38; H, 4.21.
Coupling of Ditelluride with Organoboronic Acid (Table 3):
3
)
122.4, 114.2, 113.1; IR (neat): 3065, 1893, 1573, 1470 cm ; Anal.
Calcd for C H BrTe: C, 39.96; H, 2.51. Found: C, 39.66; H, 2.62.
12
9
5
1
Entry 25. H NMR (270 MHz, CDCl
J ) 8.3 Hz, 2H), 7.62-7.61 (m, 4H), 7.59-7.25 (m, 3H); C NMR
67.5 MHz, CDCl ) δ 191.5, 139.8, 135.6, 135.1, 129.8, 128.9,
3
) δ 9.89 (s, 1H), 7.83 (d,
14 12 2
C H O
13
(
3
1
Entry 17. H NMR (270 MHz, CDCl
3
) δ 7.71-7.66 (m, 2H),
.49-7.46 (m, 1H), 7.32-7.13 (m, 5H), 6.96-6.90 (m, 1H), 2.40
s, 3H); 13C NMR (67.5 MHz, CDCl
) δ 141.8, 138.6, 137.4, 129.5,
29.3, 128.0, 127.9, 126.7, 119.1, 113.9, 26.0; IR (neat) 3052, 1949,
-1
126.6, 112.9; IR (neat): 3052, 2827, 2734, 1694, 1582 cm ; Anal.
7
(
1
1
Calcd for C13H10OTe: C, 50.40; H, 3.25. Found: C, 50.12; H, 3.35.
3
1
Entry 26. mp 71-72 °C; H NMR (270 MHz, CDCl
3
) δ 7.81-
-
1
575, 1473 cm ; Anal. Calcd for C13
H12Te: C, 52.78; H, 4.09.
7.76 (m, 4H), 7.59 (d, J ) 8.2 Hz, 2H), 7.35-7.22 (m, 3H), 3.87
(s, 3H); 13C NMR (67.5 MHz, CDCl
) δ 166.7, 139.3, 135.8, 130.0,
129.7, 129.0, 128.5, 123.2, 113.3, 52.0; IR (CHCl ): 3019, 1719,
Found: C, 52.58; H, 4.15.
3
1
Entry 18. H NMR (270 MHz, CDCl
.42-7.26 (m, 3H), 7.25-7.13 (m, 1H), 6.96-6.93 (m, 1H), 6.79-
.69 (m, 2H), 3.86 (s, 3H); 13C NMR (67.5 MHz, CDCl
) δ 158.0,
41.1, 133.5, 129.5, 128.5, 128.0, 122.3, 112.0, 109.6, 107.6, 55.8;
3
) δ 7.91-7.87 (m, 2H),
3
-
1
7
6
1
14 12 2
1587, 1435 cm ; Anal. Calcd for C H O Te: C, 49.48; H, 3.56.
3
Found: C, 49.25; H, 3.61.
-
1
IR (neat): 3062, 2937, 2833, 1572, 1469, 1431 cm ; Anal. Calcd
for C13 12OTe: C, 50.07; H, 3.88. Found: C, 49.78; H, 4.02.
Entry 19. H NMR (270 MHz, CDCl
Acknowledgment. This work was supported by Meiji Seika
Co. Ltd.
H
1
3
) δ 7.93-7.89 (m, 2H),
13
7
.46-7.22 (m, 4H), 7.12-7.05 (m, 1H), 6.96-6.92 (m, 2H); C
NMR (67.5 MHz, CDCl
28.6, 128.0, 127.3, 120.5, 113.3; IR (neat) 3053, 1567, 1473, 1443
9
cm ; Anal. Calcd for C12H ClTe: C, 45.57; H, 2.87. Found: C,
3
) δ 141.1, 136.4, 134.3, 129.9, 129.1,
1
Supporting Information Available: Analytical data ( H and
C NMR spectra) and literature citations for known compounds.
1
13
-
1
This material is available free of charge via the Internet at
http://pubs.acs.org.
4
5.26; H, 3.04.
1
Entry 22. H NMR (270 MHz, CDCl
3
) δ 7.70-7.67 (m, 2H),
7
.50 (d, J ) 8.2 Hz, 2H), 7.33-7.26 (m, 3H), 7.23-7.17 (m, 2H);
JO062131+
J. Org. Chem, Vol. 72, No. 4, 2007 1245