3432
B. C. Ranu et al. / Tetrahedron Letters 49 (2008) 3430–3432
Table 2
Acknowledgments
Pd nanoparticle-catalyzed Hiyama cross-coupling of aryl bromides and
iodides with arylsiloxanes
We are pleased to acknolwedge the financial support
from DST, New Delhi [Grant No. SR/S5/GC-02/2006]
for this investigation. R.D. and K.C. are thankful to CSIR
for their fellowships.
Na PdCl , SDS
2
4
X +
Si(OR)3
H O, NaOH
2
R1
R2
1
2
R
R
1
00 ºC
1
2
a
Entry
R
R
R
Time (min)
Yield (%)
Ref.
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
H
2-Me
H
H
H
H
H
H
H
H
H
H
H
H
4-Me
4-Me
4-Me
H
H
H
Me
5
5
5
5
5
5
5
5
5
5
5
5
6
6
6
5
5
5
96
92
90
86
90
88
94
92
95
88
92
94
80
80
75
94
90
93
7b
7b
7b
7b
7b
7b
7b
7b
7b
7b
12
7b
7b
13
13
7b
7b
7b
References and notes
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Et
Et
Et
Me
Me
Me
2-OMe
3-Me
3-OMe
3-CHO
4-Me
4-OMe
4-COMe
4-CHO
4-F
4-Cl
4-Me
3-OMe
3-NO
H
1. (a) Transition Metals for Organic Synthesis: Building Blocks and Fine
Chemicals, 2nd ed.; Beller, M., Bolm, C., Eds.; Wiley-VCH: Wein-
heim, Germany, 2004; (b) Handbook of Organopalladium Chemistry
for Organic Synthesis; Negishi, E.-I., de Meijere, A., Eds.; Wiley: New
York, 2002.
2. (a) Stille, J. K. Angew. Chem., Int. Ed. Engl. 1986, 25, 508–524; (b)
Espinet, P.; Echavarren, A. M. Angew. Chem., Int. Ed. 2004, 43,
4704–4734.
3. (a) Suzuki, A. J. Organomet. Chem. 1999, 576, 147–168; (b) Suzuki, A.
Chem. Rev. 1995, 95, 2457–2483.
4. (a) Hatanaka, Y.; Hiyama, T. J. Org. Chem. 1988, 53, 918–920; (b)
Hiyama, T. J. Organomet. Chem. 2002, 653, 58–61 and references
cited therein.
1
1
1
1
1
1
1
1
1
2
4-Me
3-NO
5. (a) Shi, S.; Zhang, Y. J. Org. Chem. 2007, 72, 5927–5930; (b) Gordillo,
A.; Jesus, E. D.; Lopez-Mardomingo, C. Org. Lett. 2006, 8, 3517–
2
3
520; (c) Alacid, E.; Najera, C. Adv. Synth. Catal. 2006, 348, 2085–
Entries 1–14, X = Br; 15–18, X = I.
a
1
13
2091; (d) Ju, J.; Nam, H.; Jung, H. M.; Lee, S. Tetrahedron Lett. 2006,
4
Isolated yields of purified products ( H and C NMR).
7, 8673–8678; (e) Pierrat, P.; Gros, P.; Fort, Y. Org. Lett. 2005, 7,
97–700; (f) Lerebours, R.; Wolf, C. Synthesis 2005, 2287–2292; (g)
6
Li, J.-H.; Deng, C.-L.; Liu, W.-J.; Xie, Y.-X. Synthesis 2005, 3039–
044; (h) Seganish, W. M.; Deshong, P. Org. Lett. 2004, 6, 4379–4381;
3
1
2
1
Ar -Ar
Ar -X
(i) Manoso, A. S.; Ahn, C.; Soheili, A.; Handy, C. J.; Correia, R.;
Seganish, W. M.; Deshong, P. J. Org. Chem. 2004, 69, 8305–8314; (j)
Wolf, C.; Lerebours, R. Org. Lett. 2004, 6, 1147–1150; (k) Lee, J.-Y.;
Fu, G. C. J. Am. Chem. Soc. 2003, 125, 5616–5617; (l) Murata, M.;
Shimazaki, R.; Watanabe, S.; Masuda, Y. Synthesis 2001, 2231–2233;
Nano Palladium
(
m) Lee, H. M.; Nolan, S. P. Org. Lett. 2000, 2, 2053–2055.
6
. (a) Astruc, D. Inorg. Chem. 2007, 46, 1884–1894; (b) Astruc, D.; Lu,
F.; Aranzaes, J. R. Angew. Chem., Int. Ed. 2005, 44, 7852–7872.
. (a) Pachon, L. D.; Thathagar, M. B.; Hartl, F.; Rothemberg, G. Phys.
Chem. Chem. Phys. 2006, 8, 151–157; (b) Srimani, D.; Sawoo, S.;
Sarkar, A. Org. Lett. 2007, 9, 3639–3642.
Ar1
Ar2
X
7
Ar1
8
. (a) Ranu, B. C.; Chattopadhyay, K. Org. Lett. 2007, 9, 2409–2412; (b)
Ranu, B. C.; Chattopadhyay, K.; Adak, L. Org. Lett. 2007, 9, 4595–
4
598; (c) Ranu, B. C.; Saha, A.; Jana, R. Adv. Synth. Catal. 2007, 349,
2
690–2696.
-
2
-
HOSi(OMe)3 + X
Ar -Si(OMe) + OH
3
9. Representative experimental procedure for the Hiyama coupling of bromo-
benzene with phenyltrimethoxysilane (Table 2, entry 1). To a stirred
Scheme 2. Possible mechanism of cross-coupling reaction.
mixture of Na
aqueous solution of NaOH (2 mL, 3 M) was added bromobenzene
157 mg, 1 mmol) followed by phenyltrimethoxysilane (239 mg,
.2 mmol). The reaction mixture was then stirred at 100 °C (oil bath
temperature) for 5 min (TLC) and extracted with ethyl acetate
3 Â 20 mL). The combined organic extract was washed with brine, dried
overanhydrousNa SO , andevaporatedtoleavethecrudeproduct, which
2 4
PdCl (4.5 mg, 1.5 mol %), SDS (57 mg, 0.2 mmol), and an
(
1
as outlined in Scheme 2. Sodium hydroxide works here as
an alternative promoter to fluoride ions used in conven-
5
g
(
5
tional procedures.
2
4
was purified by column chromatography over silica gel with hexane–ether
(99:1) as eluent to furnish pure biphenyl as a white solid (148 mg, 96%).
This procedure was followed for the synthesis of all the products listed in
Table 2. Known compounds were identified by the comparison of their
spectral data with those reported earlier (see references in Table 2).
10. Mizukoshi, Y.; Okitsu, K.; Maeda, Y.; Yamamoto, T. A.; Oshima,
R.; Nagata, Y. J. Phys. Chem. B 1997, 101, 7033–7037.
In conclusion, this procedure has a marked distinction
7
a,b
from other palladium nanoparticle-catalyzed processes,
providing a one-pot, simple and fast (5 min) operation
7
a
compared to other multi-step and lengthy reactions.
Other significant advantages offered by this procedure are
mild reaction conditions, no requirement of phosphine or
imine ligands or a fluoride source, and the reaction occurs
in water. To the best of our knowledge, this is the fastest
Hiyama coupling of aryl bromides with arylsilanes to
afford biaryl derivatives using palladium catalysis.
1
1
1. Lerebours, R.; Wolf, C. J. Am. Chem. Soc. 2006, 128, 13052–13053.
2. Feuerstein, M.; Laurenti, D.; Doucet, H.; Santelli, M. Synthesis 2001,
2
320–2326.
1
3. Grasa, A. G.; Hillier, A. C.; Nolan, S. P. Org. Lett. 2001, 3, 1077–
1080.