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M. L. Kantam et al.
LETTER
Table 2 Stille Coupling of Iodoarenes with Trialkyltin Using LDH-Pt0 Catalysta
Entry
Iodoarene
Trialkyltin
Time (h)
Isolated yield (%)
1
2
3
4
5
6
7
8
9
Iodobenzene
Phenyl tributyltin
Vinyl tributyltin
Phenyl tributyltin
Vinyl tributyltin
Phenyl tributyltin
Vinyl tributyltin
Phenyl tributyltin
Phenyl tributyltin
Phenyl tributyltin
4
6
90, 88b
92
Iodobenzene
4-Iodonitrobenzene
4-Iodonitrobenzene
4-Iodotoluene
4-Iodotoluene
4-Iodoacetophenone
4-Iodoanisole
2-Iodotoluene
4
95
4
92
8
90
8
88
4
92
12
12
94
67
a Reaction conditions: iodoarene (0.5 mmol), trialkyltin reagent (0.75 mmol), LDH-Pt0 (1 mol%), NMP (3 mL), 100 °C, nitrogen atmosphere.
b Yield after 5th cycle.
yield of trans-stilbene: 92% (NaOAc), 78% (K2CO3), 35%
(NaOH), no reaction (Bu3N).
References and Notes
(9) For preparation and characterization of LDH-Pt0 catalyst see
ref. 5. Loading of Pt in LDH-Pt0 is 0.374 mmol of Pt per
gram of catalyst. In a typical procedure for Heck coupling
using LDH-Pt0 as catalyst: in an oven-dried 10-mL round-
bottomed flask, iodobenzene (0.5 mmol), styrene (0.75
mmol), NaOAc (1.5 mmol), LDH-Pt0 (1.0 mol%), and NMP
(3 mL) were taken and stirred at 135 °C under N2
atmosphere and the reaction was monitored by TLC. After
the completion of the reaction, the catalyst was centrifuged
and reused. The centrifugate was diluted with Et2O and
washed with sat. aq NaCl solution. The organic layer was
dried with Na2SO4 and concentrated to get the crude product.
Then it was subjected to column chromatography to get the
pure product. Isolated yield of trans-stilbene was 92%.
1H NMR: d = 7.11 (s, 2 H), 7.21–7.30 (m, 2 H), 7.31–7.41 (t,
4 H, J = 7.54 Hz), 7.47–7.56 (d, 4 H, J = 7.54 Hz).
(10) Typical Procedure for Stille Coupling Using LDH-Pt0 as
Catalyst.
(1) (a) Beletskaya, I. P.; Cheprakov, A. V. Chem. Rev. 2000,
100, 3009. (b) Zapf, A.; Beller, M. Chem. Commun. 2005,
431. (c) Li, J.; Liang, Y.; Wang, D.; Liu, W.; Xie, Y.; Yin,
D. J. Org. Chem. 2005, 70, 2832.
(2) (a) Kelkar, A. A. Tetrahedron Lett. 1996, 37, 8917.
(b) Mateo, C.; Fernandez-Rivas, C.; Cardenas, D. U. J.;
Echavarren, A. M. Organometallics 1998, 17, 3661.
(c) Bhanage, B. M.; Zhao, F. G.; Shirai, M.; Arai, M.
Tetrahedron Lett. 1998, 39, 9509. (d) Bedford, R. B.;
Hazelwood, S. L. Organometallics 2002, 21, 4009. (e) Oh,
C. H.; Lim, Y. M.; You, C. H. Tetrahedron Lett. 2002, 43,
4645. (f) Horniakova, J.; Nakamura, H.; Kawase, R.;
Komura, K.; Kubota, Y.; Sugi, Y. J. Mol. Catal. A: Chem.
2005, 233, 49.
(3) (a) Corma, A.; Martin-Aranda, R. M. J. Catal. 1991, 130,
130. (b) Sels, B. F.; De Vos, D.; Buntinx, M.; Pierard, F.;
Kirsch-De Mesmaeker, A.; Jacobs, P. A. Nature (London)
1999, 400, 855. (c) Choudary, B. M.; Kantam, M. L.;
Rahman, A.; Reddy, Ch. V.; Rao, K. K. Angew. Chem. Int.
Ed. 2001, 40, 763. (d) Choudary, B. M.; Chowdari, N. S.;
Madhi, S.; Kantam, M. L. Angew. Chem. Int. Ed. 2001, 40,
4620.
(4) Choudary, B. M.; Madhi, S.; Chowdari, N. S.; Kantam, M.
L.; Sreedhar, B. J. Am. Chem. Soc. 2002, 124, 14127.
(5) Choudary, B. M.; Roy, M.; Roy, S.; Kantam, M. L. J. Mol.
Catal. A: Chem. 2005, 241, 215.
(6) Miyata, S. Clays Clay Miner. 1975, 23, 369.
(7) For Heck reaction of iodobenzene with styrene in presence
of LDH-Pt0 (1.0 mol%) using NaOAc as base at 135 °C for
6 h yield of trans-stilbene: 92% (NMP), 88% (DMF), 89%
(DMAc), 10% (MeCN), 0% (xylene).
In an oven-dried 10-mL round-bottomed flask, 4-iodo-
anisole (0.5 mmol), phenyltributyl tin (0.75 mmol), LDH-Pt0
(1.0 mol%), and NMP (3 mL) were taken and stirred at
100 °C under nitrogen atmosphere and the reaction was
monitored by TLC. After the completion of the reaction, the
catalyst was centrifuged and reused. The centrifugate was
diluted with Et2O and washed twice with aq 20% KF
solution followed by sat. aq NaCl solution. The organic layer
was dried with Na2SO4 and concentrated to get the crude
product. Then it was subjected to column chromatography to
get the pure product. Isolated yield of 4-methoxybiphenyl
was 94%.
1H NMR: d = 3.85 (s, 3 H), 6.93 (d, 2 H, J = 8.9 Hz), 7.20–
7.31 (m, 1 H), 7.33–7.44 (t, 2 H, J = 7.4 Hz), 7.46–7.56 (m,
4 H).
(8) For Heck reaction of iodobenzene with styrene in presence
of LDH-Pt0 (1.0 mol%) in NMP solvent at 135 °C for 6 h
Synlett 2006, No. 14, 2266–2268 © Thieme Stuttgart · New York