Fig. 3 Time-dependence curves of the oxidative coupling of 1 with 2 using a Pd(OAc)
Pd(OAc) /H PMo12 O/air system (B) [3 (E ), 4 (’), 5 (n), 6 (ꢃ)].
40ꢀ30H
/H
2 4
2
PMo11VO40ꢀ15H O/air system (A) and a
2
3
O
2
The product yields were estimated from the peak areas on
the basis of the internal standard technique by using GC.
a flask (50 mL) and ca. 25 mg of dodecane as internal standard
were added to the reaction mixture. Then the GC and GC-MS
analyses were performed. The products were identified
through a comparison of these analytical data with those of
authentic samples.
Preparation of H PMo VO ꢀ15H O
4
11
40
2
1
2
H
4
PMo11VO40ꢀnH
2
O was prepared by a known method.
Na HPO ꢀ26H O (0.61 g, 5 mmol) was dissolved in 10 mL
2
4
2
of water and mixed with NaVO (1.79 g, 5 mmol) which had
3
Acknowledgements
been dissolved by boiling in 10 mL of water. The mixture was
cooled and acidified to a red color with 0.5 mL of concentrated
sulfuric acid. To this mixture was added a solution of
This work was supported by a Grant-in-Aid for Scientific
Research on Priority Areas ‘‘Advanced Molecular Transfor-
mation of Carbon Resources’’ from the Ministry of Educa-
tion, Culture, Sports, Science and Technology, Japan, and
Na
2
MoO
4
ꢀ2H
2
O (13.31 g, 55 mmol) dissolved in 20 mL of
water. Finally, 8.5 mL of concentrated sulfuric acid were
added slowly with vigorous stirring of the solution. With this
addition the dark red color changed to a lighter red. The
molybdovanadophosphoric acid was then extracted with
‘‘High-Tech Research Center’’ Project for Private Universities:
matching fund subsidy from the Ministry of Education,
Culture, Sports, Science and Technology, 2005–2009. We also
thank Nippon Inorganic Colour & Chemical Co. Ltd. for a
gift of heteropoly acids.
1
00 mL of diethyl ether after the aqueous solution was cooled.
In this extraction, the molybdovanadophosphoric acid ethe-
rate was present as a middle layer; the bottom layer (water)
was yellow and probably contained vanadyl species. After
separation, the middle layer was concentrated by using a
rotary vacuum evaporator. The orange solid that remained
was allowed to crystallize in water. The orange crystals that
formed were filtered and washed with cold water. After drying
References
1 (a) Activation of unreactive bonds and organic synthesis, ed.
S. Murai, Springer, New York, 1999; (b) G. Dyker, Angew.
Chem., Int. Ed., 1999, 38, 1698; (c) C. Jia, D. Piao, J. Oyamada,
W. Lu, T. Kitamura and Y. Fujiwara, Science, 2000, 287, 1992; (d)
C. Jia, W. Lu, T. Kitamura and Y. Fujiwara, Acc. Chem. Res.,
under vacuum for 2 h, H
4
PMo11VO40ꢀ15H
2
O was obtained.
2001, 34, 633; (e) J. A. Labinger and J. E. Bercaw, Nature, 2002,
417, 507; (f) V. Ritleng, C. Sirlin and M. Pfeffer, Chem. Rev., 2002,
102, 1731.
The number of crystal waters was measured by thermogravi-
metric analysis.
2
(a) R. F. Heck, Acc. Chem. Res., 1979, 12, 146; (b) A. de Meijere
and F. E. Meyer, Angew. Chem., Int. Ed. Engl., 1994, 33, 2379; (c)
W. Cabri and I. Candiani, Acc. Chem. Res., 1995, 28, 2; (d) I. P.
Beletskaya and A. V. Cheprakov, Chem. Rev., 2000, 100, 3009; (e)
A. Biffis, M. Zecca and M. Basato, J. Mol. Catal. A: Chem., 2001,
General procedure for oxidative coupling of benzene (1) with
2 2
ethylene (2) using Pd(OAc) /HPA/O catalytic system
(
run 1 in Table 1)
1
73, 249.
(a) C. Jia, W. Lu, T. Kitamura and Y. Fujiwara, Org. Lett., 1999,
, 2097; (b) M. Dams, E. D. De Vos, S. Celen and P. A. Jacobs,
CAUTION: In order to avoid explosion of a mixture of
ethylene and air, the reaction was carried out at an ethylene
concentration outside the explosion limits ranging from 3.1 to
3
1
Angew. Chem., Int. Ed., 2003, 42, 3512.
H. Weissman, X. Song and D. Milstein, J. Am. Chem. Soc., 2001,
123, 337.
K. Sasaki, T. Sakakura, Y. Tokunaga, K. Wada and M. Tanaka,
Chem. Lett., 1988, 685.
6 (a) Y. Fujiwara, I. Moritani, S. Danno and S. Teranishi, J. Am.
Chem. Soc., 1969, 91, 7166; (b) I. Moritani and Y. Fujiwara,
Synthesis, 1973, 524.
V. E. Tarabanko, I. V. Kozhevnikov and K. I. Matveev, Kinet.
Katal., 1978, 19, 1160.
4
5
3
2%. Into a 50 mL stainless steel autoclave equipped with a
magnetic stirrer bar were placed Pd(OAc) (10 mmol),
O (10.4 mg, ca. 5 mmol), NaOAc (25
2
H
4
PMo11VO40ꢀ15H
2
mmol), dibenzoylmethane (30 mmol), 1 (30 mmol) and prop-
ionic acid (2 mL). Into the autoclave were introduced 0.9 atm
of 2 and 1.6 atm of air, and the mixture was stirred at 90 1C for
7
8
h. After the reaction, the reacted mixture was transferred to
This journal is ꢂc The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2008
New J. Chem., 2008, 32, 738–742 | 741