N. Liu et al.
ligand–Pd system to other transformations and the development
of more efficient thermoregulated ligands capable of activating
aryl chlorides are under investigation.
2-Methoxyl-5-(o-tolyl)pyridine
1
H NMR (400 MHz, CDCl3, TMS): δ 8.13 (d, J = 2.8 Hz, 1H, Py), 7.54
dd, J = 8.8 Hz, 2.4 Hz, 1H, Py), 7.28–7.19 (m, 4H, Ph), 6.79 (d,
(
1
3
J = 8.4 Hz, 1H, Py), 3.98 (s, 3H, OCH3), 2.27 (s, 3H, CH3), ppm;
C
NMR δ 163.3 (Py), 146.7 (Py), 139.7 (Py), 138.3 (Ph), 135.9 (Ph), 130.7
Experimental
(Py), 130.6 (Ph), 130.1 (Ph), 127.8 (Ph), 126.2 (Ph), 110.3 (Py), 53.6
+
General Information
(OCH3), 20.6 (CH3), ppm; MS (EI) m/z 199 (M , 100%); 200, 198,
1
70, 169, 167, 154, 141, 128, 127, 115, 102, 89, 77, 63, 48, 39.
All the reactions were carried out in nitrogen. All aryl halides
and arylboronic acids were purchased from Alfa Aesar. Other
chemicals were obtained commercially and used without any
prior purification. 1H NMR spectra were recorded on a Bruker
Acknowledgments
The authors acknowledge the financial support from the State
Key Laboratory of Fine Chemicals (KF0801), Science Research
Foundation of DUT, Graduate Student Education Reform Fund of
DUT, Special Research Foundation of DUT for Retired Professors
1
3
Avance II 400 spectrometer. C NMR spectra were recorded at
00 MHzusingTMSasinternalstandard.Massspectroscopydataof
1
the products were collected on an MS-EI instrument. All products
were isolated by short chromatography on a silica gel (200–300
(Z. Jin: DUTTX2009102), the National Natural Science Foundation
◦
mesh) column using petroleum ether (60–90 C), unless otherwise
of China (20976024 and 20923006) and the Innovative Research
Team in University (IRT0711).
noted. Compounds described in the literature were characterized
1
by H NMR spectra to reported data.
Supporting information
Synthesis of Ph2P(CH2CH2O)nCH3 (n = 22) (L)
Supporting information may be found in the online version of this
article.
Ligand L was prepared from CH3(OCH2CH2)nOSO2CH3 (n =
[
18,19]
2
2) and LiPPh2 according to the literature.
The ligand
Ph2P(CH2CH2O)nCH3 (n = 22) (15.6 g, yield 36%) was obtained.
1
H NMR (400 MHz, D2O): δ 2.39 (t, 2H), 3.37 (s, 3H), 3.55–3.65 (m,
References
9
5H), 7.31–7.50 (m, 10H) ppm. 13C NMR (100 MHz, D2O): δ 28.64
(
d), 58.75 (s), 68.16 (d), 69.88–71.70 (m), 128.17–138.15 (m) ppm.
P NMR (400 MHz, D2O): δ −22.70 ppm.
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3
1
[
[
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A 0.89 mg aliquot of PdCl2 (0.005 mmol) was added to a solution
of ligand L (11.6 mg, 0.01 mmol) in deoxygenated H2O (1 ml) in
standard Schlenk and the mixture was allowed to stir for 30 min
under nitrogen. Et3N (1 mmol, 101 mg), aryl bromide (0.5 mmol)
and arylboronic acid (0.75 mmol) were then successively added
[6] R. F. Chen, J. Y. Jiang, Y. H. Wang, Z. L. Jin, J. Mol. Catal. A: Chem.
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[
[
[
1
8] D. E. Bergbreiter, P. L. Osburn, A. Wilson, E. M. Sink, J.Am.Chem.Soc.
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◦
and the reaction mixture was heated in an oil bath at 100 C
for the designated time under nitrogen with magnetic stirring.
After cooling to room temperature, the reaction mixtures was
added to brine (15 ml) and extracted three times with diethyl
ether (3 × 15 ml). The solvent was concentrated under vacuum
and the product was isolated by short chromatography on a silica
gel (200–300 mesh) column.
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10] Y. Uozumi, Y. Matsuura, T. Arakawa, Y. M. A. Yamada, Angew. Chem.,
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6
[
Catalyst Recycling for the Suzuki Reaction
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[
Whenthereactionwascompleted,thereactionmixturewascooled
to room temperature and extracted with 2 ml ethyl ether. Et3N
[
18] M. Solinas, J. Jiang, O. Stelzer, W. Leitner, Angew. Chem., Int. Edn
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42.
2
(
1 mmol, 101 mg), aryl bromide (0.5 mmol) and phenylboronic
[
acid (0.75 mmol) were added to the aqueous phase separated
5
from the previous catalytic run under nitrogen and reacted at
[20] N. E. Leadbeater, Chem. Commun. 2005, 38, 2881.
[21] A. N. Marziale, S. H. Faul, T. Reiner, S. Schneider, J. Eppinger, Green
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◦
1
00 C.
[
22] S. Bai, T. S. A. Hor, Chem. Commun. 2008, 3172.
5
-(4-Fluorophenyl)-2-methoxylpyridine
[23] J. A. Lowe, W. Qian, S. E. Drozda, R. A. Volkmann, D. Nason,
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1
H NMR (400 MHz, CDCl3, TMS): δ 8.33 (d, J = 2.4 Hz, 1H, Py), 7.74
dd, J = 8.4 Hz, 2.4 Hz, 1H, Py), 7.49–7.45 (m, 2H, Ph), 7.15–7.11
m, 2H, Ph), 6.81 (d, J = 8.4 Hz, 1H, Py), 3.98 (s, 3H, OCH3), ppm;
(
(
1
3
C NMR δ 163.6 (Py), 162.5 (Ph), 144.8 (Py), 137.4 (Py), 134.1 (Ph),
1
29.2 (Py), 128.3 (Ph), 115.9 (Ph), 110.9 (Py), 53.57 (OCH3), ppm; MS
+
(EI) m/z 203 (M , 100%); 204, 175, 172, 146, 133, 132, 107, 83, 63.
wileyonlinelibrary.com/journal/aoc
Copyright ꢀc 2010 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. 2011, 25, 168–172