Copper oxide nanoparticle-catalyzed coupling of diaryl diselenide with aryl halides under ligand-free conditions

Article abstract of DOI:10.1021/ol802734f

A new, efficient and ligand-free cross-coupling reaction of aryl halides and diaryl diselenides using a catalytic amount of nanocrystalline CuO as a recyclable catalyst with KOH as the base in DMSO at 110 °C is reported. This protocol has been utilized for the synthesis of a variety of aryl selenides in excellent yields from the readily available aryl halides and diaryl diselenides.

Full text of DOI:10.1021/ol802734f

ORGANIC
LETTERS
2009
Vol. 11, No. 4
951-953
Copper Oxide Nanoparticle-Catalyzed
Coupling of Diaryl Diselenide with Aryl
Halides under Ligand-Free Conditions
Vutukuri Prakash Reddy, Akkilagunta Vijay Kumar, Kokkirala Swapna, and
Kakulapati Rama Rao*
Organic Chemistry DiVision-I, Indian Institute of Chemical Technology,
Hyderabad-500 007, India
kakulapatirama@gmail.com
Received November 26, 2008
ABSTRACT
A new, efficient and ligand-free cross-coupling reaction of aryl halides and diaryl diselenides using a catalytic amount of nanocrystalline CuO
as a recyclable catalyst with KOH as the base in DMSO at 110 °C is reported. This protocol has been utilized for the synthesis of a variety
of aryl selenides in excellent yields from the readily available aryl halides and diaryl diselenides.
Diaryl selenides play an importent role in organic chemistry,
acting as versatile reagents in organic synthesis1 and cataly-
sis.2 The biological and medicinal properties of selenium and
organo selenium compounds are also increasingly appreci-
ated, mainly due to their antioxidant, antitumor, antimicro-
bial, anticancer, and antiviral properties.3
Traditional methods for the formation of a C-Se bond
require photochemical or harsh reaction conditions such as
the use of polar and toxic solvents like HMPA and high
reaction temperatures,4 reaction of aryl halide and benzene-
selenate anion in liquid ammonia under UV light, reaction
of sodium selenide with arenediazonium salts, etc.5 In
general, to avoid handling unstable reagents such as selenols
because of their instability against air and/or moisture and
foul-smelling nature, diphenyl diselenides are used as starting
materials. Cristau and co-workers were the first to show that
aryl selenides can be obtained by cross-coupling of aryl
halides and sodium benzeneselenolate using Ni(II)-based
catalysts.6 Several Copper, and palladium-based catalysts in
combination with various ligands are generally employed for
this coupling reaction.7 Recently Engman reported the
synthesis of diaryl selenides in the presence of a copper(I)-
(1) (a) Krief, A.; Hevesi, L. Organoselenium Chemistry I; Springer:
Berlin, 1988. (b) Comasseto, J. V.; Ling, L. W.; Petragnani, N.; Stefani,
H. A. Synthesis 1997, 373. (c) Organoselenium Chemistry: A Practical
Approach; Back, T. G., Ed.; Oxford University Press: Oxford, UK, 1999.
(d) Procter, D. J. J. Chem. Soc., Perkin Trans. 1 2000, 835.
(2) (a) Braga, A. L.; Ludtke, D. S.; Vargas, F.; Braga, R. C. Synlett
2006, 1453. (b) Braga, A. L.; Vargas, F.; Sehnem, J. A.; Braga, R. C. J.
Org. Chem. 2005, 70, 9021. (c) Braga, A. L.; Paixao, M. W.; Ludtke, D. S.;
Silveira, C. C.; Rodrigues, O. E. D. Org. Lett. 2003, 5, 3635. (d) Braga,
A. L.; Silva, S. J. N.; Ludtke, D. S.; Drekener, R. L.; Silveira, C. C.; Rocha,
J. B. T.; Wessjohann, L. A. Tetrahedron Lett. 2002, 43, 7329. (e) Braga,
A. L.; Paixao, M. W.; Marin, G. Synlett 2005, 1975. (f) Braga, A. L.; Ludtke,
D. S.; Sehnem, J. A.; Alberto, E. E. Tetrahedron 2005, 61, 11664.
(3) (a) Back, T. G.; Moussa, Z. J. Am. Chem. Soc. 2003, 125, 13455.
(b) Nogueira, C. W.; Zeni, G.; Rocha, J. B. T. Chem. ReV. 2004, 104, 6255.
(c) Anderson, C.-M.; Hallberg, A.; Hogberg, T. AdV. Drug. Res. 1996, 28,
65. (d) Clark, L. C.; Combs, G. F.; Turnbull, B. W.; Slate, E. H.; Chalker,
D. K.; Chow, J.; Davis, L. S.; Glover, R. A.; Graham, G. F.; Gross, E. G.;
Krongrad, A.; Lesher, J. L.; Park, K.; Sanders, B. B.; Smith, C. L.; Taylor,
R. J. Am. Med. Assoc. 1996, 276, 1957.
(4) (a) Suzuki, H.; Abe, H.; Osuka, A. Chem. Lett. 1981, 151. (b) Osuka,
A.; Ohmasa, N.; Suzuki, H. Synth. Commun. 1982, 857. (c) Andersson,
C. M.; Hallberg, A.; Linden, M.; Brattsand, R.; Moldeus, P.; Cotgreave, I.
Free Radic. Biol. Med. 1994, 16, 17. (d) Andersson, C. M.; Hallberg, A.;
Hugberg, T. AdV. Drug Res. 1996, 28, 65.
(5) (a) Ayrey, G.; Barnard, D.; Woodbridge, D. T. J. Chem. Soc. 1962,
2089. (b) Pierini, A. B.; Rossi, R. A. J. Organomet. Chem. 1978, 144. (c)
Pierini, A. B.; Rossi, R. A. J. Org. Chem. 1979, 44, 4667. (d) Rossi, R. A.;
Penerori, A. B. J. Org. Chem. 1984, 46, 4580. (e) Tiecco, M.; Testaferri,
L.; Tingoli, M.; Chianelli, D.; Montanucci, M. Tetrahedron Lett. 1984, 25,
4975. (f) Tiecco, M.; Testaferri, L.; Tingoli, M.; Chianelli, D.; Montanucci,
M. J. Org. Chem. 1983, 48, 4289.
(6) Cristau, H. J.; Chabaud, B.; Labaudiniere, R.; Christol, H. Organo-
metallics 1985, 4, 657.
10.1021/ol802734f CCC: $40.75
Published on Web 01/30/2009
2009 American Chemical Society

catalyst, 2,2′-bipyridyl and magnesium under microwave
heating.8 Most of these metal-catalyzed reactions involve
specially designed ligands or well-defined catalysts/reagents,
which may increase the cost and limit the scope of applica-
tions. It is desirable to find novel catalytic procedures
especially in the absence of any ligand for an efficient access
to such highly useful organic products.
Cs2CO3 provided the arylated compound 3a in moderate to
excellent yields (Table 1, entries 2, and 4) where as other
Table 1. Nano CuO Oxide-Catalyzed Cross-Coupling of
Diphenyl Diselenide with Iodobenzenea
entry
base
solvent
temp (°C)
yieldb (%)
In general, nanoscale heterogeneous catalysts offer higher
surface area and low-coordinated sites, which are responsible
for the higher catalytic activity.9 However, till now, the
investigation of nanoparticles as catalysts has been rare. In
this regard, we envisaged the application of readily available
and inexpensive copper oxide nano particles as a catalyst.
Recently, it has been employed as a heterogeneous catalyst
for various organic transformations.10 This inspired us to
focus on the aspect of copper oxide nano particle catalysis
for the formation of aryl-selenium bonds. The copper based
catalysts are also attractive both from economic and industrial
points of view as compared to palladium.
Herein, we wish to report the catalysis by copper oxide
nanoparticles for the formation of aryl-selenium bonds in a
very efficient manner. In a preliminary reaction, iodobenzene
1 was treated with diphenyl diselenide 2 in the presence of
2 mol % of CuO nano particles and KOH (2.0 equiv) in
DMSO (2.0 mL) for 12 h, the corresponding diaryl selenide
3a was obtained in 94% yield (Scheme 1). To the best of
1
2
3
4
5
6
7
8
K3PO4
Cs2CO3
KOtBu
KOH
KOH
KOH
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
PhMe
DMF
DMSO
PhMe
PhMe
DMF
110
110
110
110
80
26
71
trace
94
76
25
trace
trace
trace
0
rt
KOH
KOH
110
110
110
110
110
110
110
110
9
NaOMe
Cs2CO3
KOtBu
Cs2CO3
KOH
10
11
12
13
14
0
trace
0
0
Water
DMSO
none
a Reaction conditions: Iodobenzene (1.0 mmol), diphenyl diselenide (0.5
mmol), CuO (2.0 mol %), base (2.0 equiv), solvent (2.0 mL), 110 °C, 12 h,
under a nitrogen atmosphere. b Isolated yield.
bases such as K3P04, KOtBu, and NaOMe gave trace amounts
of diaryl selenide (Table 1 entries 1, 3, 7-9, and 12).
Solvents other than DMSO, such as DMF, and toluene were
less effective. Of the bases tested, KOH gave the best results
with DMSO as the solvent.11
Next, we investigated the effect of different combinations
of various metal nano oxides on the diaryl selenide formation
with KOH in DMSO at 110 °C using different substituted
aryl iodides (Table 2). However, their catalytic activities were
Scheme 1
.
CuO Nanoparticles Catalyzed C-Se Coupling
Reaction
Table 2. Evaluation of Different Catalyst for the Formation of
Diphenyl Selenidea
our knowledge, this is the first CuO nano particles-catalyzed
coupling of aryl halides with diphenyl diselenide to form
diaryl selenide.
To optimize the reaction conditions, first we tried the
dependence of the Se-arylation of iodobenzene 1 with
diphenyl diselenide 2 on the nature of the base. KOH and
(7) (a) Gujadhur, R. K.; Venkataraman, D. Tetrahedron Lett. 2003, 44,
81. (b) Taniguchi, N.; Onami, T. J. Org. Chem. 2004, 69, 915. (c)
Nishiyama, Y.; Tokunaga, K.; Sonoda, N. Org. Lett. 1999, 1, 1725. (d)
Beletskaya, I. P.; Sigeev, A. S.; Peregudov, A. S.; Petrovskii, P. V. J.
Organomet. Chem. 2000, 605, 96.
(8) Kumar, S.; Engman, L. J. Org. Chem. 2006, 71, 5400.
(9) (a) Pacchioni, G. Surf. ReV. Lett. 2000, 7, 277. (b) Knight, W. D.;
Clemenger, K.; de Heer, W. A.; Saunders, W. A. M.; Chou, Y.; Cohen,
M. L. Phys. ReV. Lett. 1984, 52, 2141. (c) Kaldor, A.; Cox, D.; Zakin,
M. R. AdV. Chem. Phys. 1988, 70, 211.
(10) (a) Rout, L.; Sen, T. K.; Punniyamurthy, T. Angew. Chem., Int.
Ed. 2007, 46, 5583. (b) Choudary, B. M.; Kantam, M. L.; Ranganath,
K. V. S.; Mahender, K.; Sreedhar, B. J. Am. Chem. Soc. 2004, 126, 3396.
(c) Choudary, B. M.; Ranganath, K. V. S.; Pal, U.; Kantam, M. L.; Sreedhar,
B. J. Am. Chem. Soc. 2005, 127, 13167. (d) Kantam, M. L.; Laha, S.; Yadav,
J.; Choudary, B. M.; Sreedhar, B. AdV. Synth. Catal. 2006, 348, 867. (e)
Zhang, J.; Zhang, Z.; Wang, Y.; Zheng, X.; Wang, Z. Eur. J. Org. Chem.
2008, 511. (f) Beckers, J.; Rothenberg, G. Dalton Trans. 2008, 6573. (g)
Thathagar, M. B.; Beckers, J.; Rothenberg, G. AdV. Synth. Catal. 2003,
345, 979.
a Reaction conditions: Iodobenzene (1.0 mmol), diphenyl diselenide (0.5
mmol), catalyst (2.0 mol %), KOH (2.0 equiv), DMSO (2.0 mL), 110 °C,
under a nitrogen atmosphere. b Isolated yield.
much lower than CuO nano particles. The yields were highly
dependent upon the reaction temparatures and the base.
952
Org. Lett., Vol. 11, No. 4, 2009

To explore the scope of this novel transformation, a
coupling reaction of diphenyl diselenide with various sub-
stituted aryl halides was evaluated (Table 3). In general, all
not successful. To check for recyclability, the catalyst was
centrifuged from the reaction mixture and dried in vacuo. It
could then be reused for further catalytic reactions. The yields
of diaryl selenides after two to three recycles were almost
same without loss of catalytic activity (Table 4).
Table 3. CuO-Nanoparticle-Catalyzed Cross-Coupling of
Iodobenzene with Diphenyl Diselenidea
Table 4. Recycling of CuO Nanoparticles
recycles
yield (%)
catalyst recovery (%)
1
2
3
94
91
90
93
91
89
A plausible mechanism for the CuO nano particle cata-
lyzed C-Se cross-coupling of arylhalides and diphenyl
diselenide is illustrated in Scheme 2.
Scheme 2. Plausible Reaction Pathway for the
CuO-Nanoparticle-Catalyzed C-Se Cross-Coupling of aryl
halides with Diphenyl Diselenide in the Presence of KOH
In conclusion, we have developed a nanocrystalline CuO-
catalyzed coupling of aryl halides with diphenyl diselenide
to form diaryl selenide under ligand-free conditions in
excellent yields. This new coupling reaction underlines the
potential of using nanocrystalline CuO as a very user-
friendly, inexpensive, and efficient catalyst for the coupling
of carbon-heteroatom. The catalyst can be easily recovered
and reused. We are in the process of expanding the substrate
scope of the reaction.
a Reaction condition: Diphenyl diselenide (0.5 mmol), iodobenzene (1.0
mmol), CuO nanoparticles (2.0 mol %), KOH (2.0 equiv) and DMSO (2.0
mL) were stirred under a nitrogen atmosphere, 110 °C. b Yield of the isolated
product.
reactions were very clean, and the diaryl selenides were
obtained in high yields under the optimized conditions. This
protocol efficiently coupled diphenyl diselenide with electron-
rich and electron-neutral and electron-deficient aryl iodides
(Table 3, entries 1-18). Sterically demanding ortho substit-
uents did not hamper the arylation reaction and the corre-
sponding diaryl selenides were obtained in good yield (Table
3, entries 14, 15). Furthermore, iodobenzene was a more
reactive substrate than chlorobenzene or bromobenzene
(Table 3, entries 1, 2, 3). Consequently, cross-coupling
reactions with chloro substituted aryl iodides proceeded
exclusively at the iodo group. Unfortunately, all attempts to
couple aliphatic dimethyl diselenide with aryl halides were
Acknowledgment. We thank CSIR and UGC, New Delhi,
for the award of fellowships.
Supporting Information Available: Detailed experimen-
tal procedures and copies of analytical data. This material is
available free of charge via the Internet at http://pubs.acs.org.
OL802734F
(11) In this reaction, DMSO may also be acting as a reducing agent
required in the reaction by producing dimsyl ion in the presence of KOH
as suggested by one of the reviewers. Hunter, D. H.; Cram, D. J. J. Am.
Chem. Soc. 1966, 88, 5765.
Org. Lett., Vol. 11, No. 4, 2009
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