Reusable and sustainable nanostructured skeleton catalyst: Heck reaction with nanoporous metallic glass Pd (PdNPore) as a support, stabilizer and ligand-free catalyst

Article abstract of DOI:10.1002/adsc.201100358

Nanoporous metallic glass palladium (PdNPore), which was fabricated by de-alloying of a glassy metallic alloy Pd₃₀Ni₅₀P ₂₀, exhibited a remarkable catalytic activity for the Heck reaction of versatile aryl iodides and aryl bromides. Moreover, the PdNPore can be reused several times without a significant loss of catalytic activity, and the PdNPore has ahigher resistance to leaching than palladium black and palladium on carbon. Copyright

Full text of DOI:10.1002/adsc.201100358

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DOI: 10.1002/adsc.201100358
Reusable and Sustainable Nanostructured Skeleton Catalyst:
Heck Reaction with Nanoporous Metallic Glass Pd (PdNPore)
as a Support, Stabilizer and Ligand-Free Catalyst
Tetsuro Kaneko,a Shinya Tanaka,b Naoki Asao,c,* Yoshinori Yamamoto,c,*
Mingwei Chen,c Wei Zhang,d and Akihisa Inoued
a
Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
Center for Integrated NanoTechnology Support, Tohoku University, Sendai 980-8577, Japan
WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
b
c
Fax : (+81)-22-795-3899; e-mail: asao@m.tohoku.ac.jp or yoshi@m.tohoku.ac.jp
Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
d
Received: May 11, 2011; Revised: August 2, 2011; Published online: November 7, 2011
Dedicated to Professor Alfred Ricci for his long-standing excellent contribution to Organic Chemistry.
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/adcs.201100358.
Abstract: Nanoporous metallic glass palladium
(PdNPore), which was fabricated by de-alloying of
a glassy metallic alloy Pd30Ni50P20, exhibited a re-
markable catalytic activity for the Heck reaction of
versatile aryl iodides and aryl bromides. Moreover,
the PdNPore can be reused several times without a
significant loss of catalytic activity, and the
PdNPore has ahigher resistance to leaching than
palladium black and palladium on carbon.
either by acid treatment or by electrolysis, leading to
Pdx’M1 M2 in which x’> x, y’<y or even y’=0, and
y’
z’
z’<z or even z’=0.[9] By this de-alloying, the nanopo-
rous Pd skeleton is formed because of removal (and
elimination) of M1 and M2 [Eq. (1)]. This discovery
Keywords: Heck reaction; metallic glass; nanopo-
rous materials; palladium; skeleton catalyst
The solid Pd catalytic system offers many advantages
from the practical viewpoint, such as easy separation prompted us to investigate the scope and limitation of
of catalysts from the reaction mixture and reusability PdNPore (Pd nanoporous skeleton catalyst) towards
for multiple runs, over the homogeneous Pd molecu- theHeck reaction.
lar catalyst system.[1] In general, as solid Pd catalysts,
The Heck reaction is a well known catalytic aryl-
supported materials such as activated carbon[2], poly- olefin bond formation reaction, and is widely utilized
mer or copolymer[3], zeolite[4], mesoporous silica[5], in organic synthesis from small scale to the industrial
and dendrimer[6] are used. On the other hand, a solid process.[10–12] Herein, we wish to report that nanopo-
Pd catalyst, prepared by manipulation of metal mor- rous metallic glass Pd (PdNPore) catalyzes the Heck
phology, has been rarely investigated. Previously, we reaction of various aryl iodides and aryl bromides
were successful in using nanoporous gold skeleton (Scheme 1). Furthermore, investigation of its leaching
material as a useful solid catalyst for the hydrolysis of
silanes.[7] More recently, we have discovered that
nanoporous Pd skeleton catalyst exhibits an excellent
activity for the Suzuki cross-coupling reaction.[8] Fab-
rication of nanoporous Pd skeleton catalyst is very
straightforward ; an alloy – PdxM1 M2 – is de-alloyed Scheme 1. PdNPore-catalyzed Heck reaction.
y
z
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Tetsuro Kaneko et al.
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Table 1. Optimization of the reaction conditions for the met-
monium salts are well known as the stabilizers of Pd
particles.[1f] Hence, TBAI might stabilize the dissolved
Pd species even in the case of the current catalytic
system, and the resulting Pd species accelerated the
desired Heck reaction (vide infra). TBACl and
TBABr were less effective due to their low solubilities
in MeOH. On the other hand, no coupling products
were obtained at all in the absence of PdNPore cata-
lyst (entry 5) or in the presence of unde-alloyed met-
allic glass Pd30Ni50P20 ribbon (entry 6). These results
indicate that the nanoporous structure played a cru-
cial role in catalyzing the reaction.
We then examined the substrate generality under
the reaction conditions both with and without TBAI
(Table 2). The reaction of 2-iodotoluene 1b with
acrylic acid 2a in the absence of TBAI gave 3b in
80%. The addition of TBAI improved the chemical
yield up to 99% (entry 1). The reactions with MeO-
and Cl-substituted iodobenzenes in the presence of
TBAI proceeded smoothly to give the corresponding
products in high yields (entries 3 and 4). The chemical
allic glass Pd-catalyzed Heck reaction.[a]
Entry 1a:2a PdNPore
Additive Time Yield [%] of
[mol%]
[h]
3a[b]
1[c]
2
1:1.5
1.5:1
1.5:1
1.5:1
1.5:1
1.5:1
2
2
1
2
–
2
–
–
–
20
20
20
18
24
24
34
84
50
94
0
3[d]
4[e]
5[e,f]
6[e,g]
TBAI
TBAI
TBAI
0
[a]
Reaction conditions: 1a (0.75 mmol), 2a (0.50 mmol),
KOH (1.5 mmol), PdNPore (0.01 mmol), MeOH (2 mL),
808C, 18–24 h.
[b]
Yield was determined by 1H NMR using CH2Br2 as an in-
ternal standard.
[c]
[d]
1a (0.50 mmol), 2a (0.75 mmol) were used.
1a (1.5 mmol), 2a (1.0 mmol), KOH (3.0 mmol), PdNPore
(0.01 mmol), MeOH (4 mL) were used.
Reaction was carried out in the presence of TBAI
(0.55 mmol).
Reaction was carried out in the absence of PdNPore cat-
alyst.
The un-de-alloyed metallic glass Pd30Ni50P20 was used in-
stead of the PdNPore catalyst.
Table 2. PdNPore-catalyzed Heck reaction with iodo-
AHCTUNGTRENNUNG
arenes.[a]
[e]
[f]
[g]
Entry
1
1
Time [h] Product, yield [%][b,c]
property revealed that PdNPore has higher resistance
to leaching compared with commercially available Pd
black and Pd/C.
1b
24
3b, 99 (80)
We initially examined the reaction of iodobenzene
(1a) with acrylic acid (2a) (Table 1). The requisite
PdNPore catalyst was fabricated by electrochemical
de-alloying of metallic glass Pd30Ni50P20 ribbon in
1 mol/L H2SO4 using a classical three-electrode set-up
according to the literature procedures.[9a] EDX spec-
tra indicated the composition of the resulting
PdNPore was Pd78Ni13P9.[13] The reaction using KOH
as a base in the presence of 2 mol% of PdNPore in
MeOH at 808C for 20 h gave cinnamic acid 3a in
34% yield (entry 1). This observation means that
PdNPore can catalyze the Heck reaction in spite of its
monolithic metal morphology. Since 1a was consumed
completely under these conditions, we thought that a
dehalogenation reaction might occur, and this side re-
action would decrease the chemical yield of desired
product 3a. To our delight, the chemical yield was
dramatically improved by use of an excess amount of
1a (entry 2). Reducing the catalytic amount to
1 mol% decreased the chemical yield to 50%
(entry 3). Finally, we found the addition of tetra-n-
2
3
4
5
1c
1d
1e
1f
24
24
24
24
3c, 92 (65)
3d, 95 (74)
3e, 95 (55)
3f, 43 (65)
6
1g
21
3g, 89 (57)
[a]
Reaction conditions:
1 (0.75 mmol), 2a (0.50 mmol),
KOH (1.5 mmol), PdNPore (0.01 mmol), TBAI
(0.55 mmol), MeOH (2 mL), 808C, 21–24 h.
Isolated yield.
The values in the parenthesis are the chemical yields in
the absence of TBAI.
[b]
[c]
but
ACHTUNGTRENNUNGylammonium iodide (TBAI) improved the chemi-
cal yield of 3a up to 94% (entry 4). Tetra-n-butylam-
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Reusable and Sustainable Nanostructured Skeleton Catalyst: Heck Reaction
yield of 3f was low in the reaction of 1f because sig- of PdNPore in N,N-dimethylacetamide (DMAc) at
nificant amounts of unidentified by-products were 1408C for 15 h resulted in the formation of 3e in
formed. Interestingly, the chemical yield was in- nearly quantitative yield (entry 1). In this reaction,
creased when the reaction was carried out in the ab- since the side reaction such as dehalogenation did not
sence of TBAI (entry 5). The reaction also worked occur, an excess amount of aryl bromide was not re-
with sterically hindered 1-iodonaphtalene (1g), and quired. Besides 2a, styrene (2b) was a suitable cou-
the corresponding products were obtained in good pling partner in this transformation and the corre-
yield in the case of using TBAI (entry 6). The reac- sponding product 3h was obtained in 99% yield
tions of iodobenzene (1a) with various other alkenes, (entry 2). The reaction rate was considerably depen-
such as methacrylic acid, crotonic acid, phenyl vinyl dent on the substituents on the bromoarenes. While
sulfone, butyl vinyl ether and styrene, gave the corre- the reaction of 4-bromobenzotrifluoride (1i) was com-
sponding coupling products in less than 10% yield.
pleted within 20 h, the reactions of bromobenzene
We next examined the reactions with less reactive (1j) and 4-bromoanisole (1k) required 48 h and 72 h,
bromoarenes (Table 3). Since the conditions for aryl respectively (entries 3–5). In contrast, both electron-
iodides were not suitable for aryl bromides, we opti- donating and electron-withdrawing groups on the
mized the conditions again. Finally, we found that the benzene ring of styrene had no negative effect on the
Kçhlerꢁs conditions[14] were suitable for the reaction reaction time (entries 6 and 7). We wondered if these
of aryl bromides. The treatment of 4-bromoacetophe- reaction conditions are suitable for the reactions of
none (1h) with acrylic acid in the presence of 2 mol% aryl iodides or aryl bromides. Unfortunately, however,
these reaction conditions was not suitable for the re-
actions of aryl iodides because of the formation of
Table 3. PdNPore-catalyzed Heck reaction with bromo-
ACHTUNGTRENNUNG
arenes.[a]
large amounts of by-products. On the other hand, no
reaction occurred in the reaction of 4-chloroacetophe-
none with styrene.
The Heck reaction is well known to be catalyzed by
Pd/C, which is one of the most accessible heterogene-
ous Pd catalysts. However, it has a serious limitation
on the recyclability. For example, the reaction of bro-
mobenzene with styrene with Pd/C catalyst has been
reported, and stilbene was obtained in 85%. Howev-
er, the chemical yield was dramatically decreased
with the reused catalyst to 57% (1st re-use) and 3%
(2nd re-use).[14] We also checked the reusability of Pd/
C under our reaction conditions using 1h and 2b. As
we expected, the chemical yield was decreased by re-
cycling (1st;>99%, 2nd; 61%, 3rd; 43%).[13] In con-
trast, the PdNPore catalyst can be recycled without
losing its activity. For example, 3h was obtained from
the reaction of 1h and 2b quantitatively at least 5
times (Table 4). SEM images of freshly prepared
PdNPore and the used one are shown in Figure 1.
These images clearly indicated that nanoporous struc-
tures were well maintained even after 5 runs. Further-
more, any significant changes of the composition of
the catalysts were not observed before and after reac-
tion by energy-dispersive X-ray (EDX) analysis.[13]
These results clearly indicate that PdNPore is a robust
and recyclable catalyst for the Heck reaction.
Entry
1
2
Time
[h]
Product, yield
[%][b]
1
2
1h
1h
2a 15
2b 12
3e, >99
3h, 99
3
4
5
6
1i
2b 20
2b 48
2b 72
2c 12
2d 12
3i, 93
3j, 92
3k, 80
3l, 86
3m, 81
1j
1k
1h
1h
We next examined the reaction to know whether a
dissolved Pd species in solvents participates in the
current molecular transformation or not.[13,15] The re-
action of 1h with 2b was carried out for 2 h under the
7
1
standard conditions. H NMR analysis indicated that
[a]
3h was produced in 19% yield at this time. Then,
PdNPore catalyst was removed by tweezers under an
inert atmosphere, and the residual homogeneous solu-
tion was stirred at 1408C for 10 h. Finally, 3h was ob-
Reaction conditions:
1 (0.50 mmol), 2 (0.75 mmol),
NaOAc (1.5 mmol), PdNPore (0.01 mmol), DMAc
(0.5 mL), 1408C, 15-72 h.
Isolated yield.
[b]
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Tetsuro Kaneko et al.
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Figure 1. Scanning electron microscopy (SEM) images of PdNPore: a) before reaction, b) after 5 times runs of Heck reaction
of 4-bromoacetophenone with styrene.
Table 4. Reusability of nanoporous metallic glass Pd on
ever, under the typical reaction conditions for 12 h,
3h was obtained nearly quantitatively as shown in
entry 2 of Table 3. This means that the leached
amount should be quite small. Then, we next investi-
gated the leaching amount from PdNPore and com-
pared it with those from the ordinary solid Pd cata-
lysts, Pd/C and Pd black. We conducted the reactions
of 1h and 2b with these three catalysts, independently.
After the reactions were completed, these Pd catalysts
were removed from the reaction mixtures. The leach-
ing amounts of Pd species in the remaining solutions
were determined by inductivity coupled plasma mass
spectrometry (ICP-MS).[13] On the basis of the aver-
age of the specific surface areas of these catalysts, the
leaching amounts of Pd per unit surface area can be
calculated and the results are summarized in Table 5.
Obviously, the leaching amount from the PdNPore
catalyst is rather smaller than those from the other
two comercially available catalysts. This result clearly
indicated that PdNPore has a higher resistant proper-
ty against leaching than the other two catalysts.
Heck reaction of 4-bromoacetophenone.[a]
Run
PdNPore
Yield [%] of 3h[b]
1
2
3
4
5
fresh
99
99
99
99
99
reuse 1
reuse 2
reuse 3
reuse 4
[a]
Reaction conditions: 1h (0.50 mmol), 2b (0.75 mmol),
NaOAc (1.5 mmol), PdNPore (0.01 mmol), DMAc
(0.5 mL).
[b]
Yield was determined by 1H NMR using CH2Br2 as an in-
ternal standard.
tained in 67% yield. This result indicates that the Kçhler reported that the Pd concentration in solution
leached Pd species participates in the catalysis. How- in the Pd/C-catalyzed reaction was highest at the be-
Table 5. Pd materials-catalyzed Heck reaction of 4-bromoacetophenone with styrene and a comparison of Pd leaching
amount as detected by ICP-MS after the reaction.[a]
Pd cat.
Time [h] Yield [%] of 3h Leaching amount in Average of specific
Leaching amount per unit
solution [mg][d]
Ysurface area [m2 gÀ1] surface area [mgmÀ2]
PdNPore
12
3
6
99
88
95
0.57
3.80
48.2
13[e]
50[f]
83[f]
43.8
76.0
580.7
Pd black[b]
Pd/C (10 wt%)[c]
[a]
Reaction conditions: 1h (0.50 mmol), 2b (0.75 mmol), NaOAc (1.5 mmol), Pd cat. (0.01 mmol), DMAc (0.5 mL), 1408C,
3–12 h.
[b]
[c]
[d]
[e]
[f]
Purchased from Aldrich Chemical Co. (product no. 205834).
Purchased from Kawaken Fine Chemicals Co., Ltd. [10 wt% Pd/C (M) Dry].
Total amount in the reaction solution.
See ref.[9a]
Product specification (see also Supporting Information).
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Reusable and Sustainable Nanostructured Skeleton Catalyst: Heck Reaction
was extracted with diethyl ether three times. The combined
ginning of the reaction and was a minimum at the end
of the reaction by the reprecipitation of Pd onto the
support.[14] It is worth mentioning that the leaching
amount from the non-supported PdNPore is smaller
than that from the supported Pd/C even at the end of
the reaction.
extracts were dried over anhydrous Mg2SO4 and evaporated.
The resulting crude product was purified by silica gel
column chromatography with hexane:AcOEt=1:2 to give
3a; yield: 94%. The purity of this product was analyzed by
1H NMR to be more than 98%.
For the reaction of bromoarenes, the preparation of 3h
(Table 3, entry 2) is representative: To a V-shaped vial reac-
tor containing a suspension of PdNPore (1.0 mg, 2 mol%),
NaOAc (50 mg, 0.60 mmol) and 4-bromoacetophenone (1h,
100 mg, 0.50 mmol) in N,N-dimethylacetamide (0.5 mL) was
added styrene (2b, 86 mL, 0.75 mmol) at room temperature.
The resulting mixture was stirred for 12 h at 1408C with a
bulky round-shaped magnetic stirring bar to avoid the con-
tact between the catalyst and stirring bar. After cooling to
room temperature, the liquid phase was transferred to the
separation funnel by a pipette and the residual inorganic
salt was also transferred to the separation funnel with water,
and aqueous layer was extracted with diethyl ether three
times. The combined extracts were dried over anhydrous
Mg2SO4 and evaporated. The resulting crude product was
purified by silica gel column chromatography with hex-
In conclusion, we have disclosed that a nanoporous
palladium catalyst fabricated from Pd-Ni-P metallic
glass exhibited a remarkable catalytic activity in the
Heck reaction without any support, stabilizer, and
ligand in spite of its monolithic metal morphology.
The advantages of the current catalytic system are (i)
easy separation of the catalyst from the products
without cumbersome filtration or centrifugation, (ii)
effective reusability of the catalyst at least five times
without any loss of catalytic activity, and (iv) smaller
leaching amounts of Pd species into the reaction solu-
tion than those of Pd black and Pd/C. Further studies
to explore the potential of PdNPore in catalysis are
now under progress.
AHCTUNGTREGNUNaN ne:Et2O=7:1 to give 3a; yield; 99%. The purity of this
1
product was analyzed by H NMR to be more than 98%.
Experimental Section
Fabrication of Manoporous Metallic Glass Pd
Acknowledgements
The mother alloy Pd30Ni50P20 was prepared by arc melting a
mixture of pure Ni and Pd metals and pre-alloyed Pd-P
ingots in an argon atmosphere. The rapidly solidified ribbon
sample with a thickness of about 20 mm was prepared by the
single-roller melt spinning technique. A classical three-elec-
trode set-up (Iviumstat electrochemical interface, Ivium
Technology) was employed to de-alloy the Pd30Ni50P20 glassy
ribbons using an Ag/AgCl electrode as the reference. A sec-
tion of Pd30Ni50P20 ribbon (approximately 5 cmꢂ1 mmꢂ
20 mm) was placed as the working electrode and a pure plat-
inum sheet positioned parallel to the Pd30Ni50P20 sample was
used as the counter electrode. The electrolyte was 500 mL
of 1 mol/L H2SO4 which was prepared from concentrated
H2SO4 and deionized water and was used immediately. De-
alloying of the Pd30Ni50P20 metallic glasses was conducted at
0.8 V for 2 h at room temperature. The de-alloyed samples
were taken out of the solution and rinsed with deionized
water and acetone for several times, then dried.
This research was partly supported by a Grant-in-Aid for Sci-
entific Research from The Ministry of Education, Culture,
Sports, Science and Technology of Japan and Japan Society
for the Promotion of Science.
References
[1] For reviews, see; a) L. Yin, J. Liebscher, Chem. Rev.
2007, 107, 133–173; b) D. Astruc, Inorg. Chem. 2007,
46, 1884–1894; c) Y. Tsuji, T. Fujihara, Inorg. Chem.
2007, 46, 1895–1902; d) N. T. S. Phan, M. Van Der
Sluys, C. W. Jones, Adv. Synth. Catal. 2006, 348, 609–
679; e) R. Narayanan, Molecules 2010, 15, 2124–2138;
f) D. Astruc, F. Lu, J. R. Aranzaes, Angew. Chem. 2005,
117, 8062–8083; Angew. Chem. Int. Ed. 2005, 44, 7852–
7872; g) A. Roucoux, J. Schulz, H. Patin, Chem. Rev.
2002, 102, 3757–3778.
[2] For a review, see: M. Seki, Synthesis 2006, 2975–2992.
[3] a) A. Ohtaka, T. Teratani, R. Fujii, K. Ikeshita, O. Shi-
momura, R. Nomura, Chem. Commun. 2009, 7188–
7190; b) I. Beletskaya, A. Kashin, I. Khotina, A.
Khokhlov, Synlett 2008, 1547–1552; c) H. Hagio, M. Su-
giura, S. Kobayashi, Org. Lett. 2006, 8, 375–378; d) R.
Akiyama, S. Kobayashi, J. Am. Chem. Soc. 2003, 125,
3412–3413.
[4] a) B. Yuan, Y. Pan, Y. Li, B. Yin, H. Jiang, Angew.
Chem. 2010, 122, 4148–4152; Angew. Chem. Int. Ed.
2010, 49, 4054–4058; b) L. Artok, H. Bulut, Tetrahedron
Lett. 2004, 45, 3881–3884; c) H. Bulut, S. Yilmaz, Tetra-
hedron Lett. 2003, 44, 289–291; d) M. Dams, L. Drijko-
ningen, B. Pauwels, G. Van Tendeloo, D. E. De Vos,
P. A. Jacobs, J. Catal. 2002, 209, 225–236; e) L. Djako-
General Procedures for Heck Reactions
For the reaction of iodoarenes, the preparation of 3a
(Table 1, entry 2) is representative: To a solution of TBAI
(203 mg, 0.55 mmol), KOH (84 mg, 1.5 mmol) in MeOH
(2 mL) were added iodobenzene (1a, 84 mL, 0.75 mmol) and
acrylic acid (2a, 35 mL, 0.50 mmol) at room temperature.
The resulting homogeneous solution was added to a V-
shaped vial reactor containing PdNPore (1.0 mg, 2 mol%),
and the reaction mixture was stirred for 20 h at 808C with a
bulky round-shaped magnetic stirring bar to avoid the con-
tact between the catalyst and stirring bar. After cooling to
room temperature, the liquid phase was transferred to the
separation funnel by a pipette and theaqueous layer was
acidified with 2M HCl to afford the free carboxylic acid and
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Tetsuro Kaneko et al.
COMMUNICATIONS
vitch, K. Koehler, J. Am. Chem. Soc. 2001, 123, 5990–
5999.
[11] M. Oestreich, (Ed.), The Mizoroki–Heck Reaction,
John Wiley & Sons, Chichester, 2009.
[5] a) C. M. Crudden, M. Sateesh, R. Lewis, J. Am. Chem.
Soc. 2005, 127, 10045–10050; b) J. D. Webb, S. Mac-
Quarrie, K. McEleney, C. M. Crudden, J. Catal. 2007,
252, 97–109; c) L. Li, J.-L. Shi, J.-N. Yan, Chem.
Commun. 2004, 1990–1991.
[6] a) Y. Li, M. A. El-Sayed, J. Phys. Chem. B 2001, 105,
8938–8943; b) E. H. Rahim, F. S. Kamounah, J. Freder-
iksen, J. B. Christensen, Nano Lett. 2001, 1, 499–501;
c) A. K. Diallo, C. Ornelas, L. Salmon, J. R. Aranzaes,
D. Astruc, Angew. Chem. 2007, 119, 8798–8802; Angew.
Chem. Int. Ed. 2007, 46, 8644–8648.
[12] For general reviews on the Heck reaction, see; a) R. F.
Heck, Acc. Chem. Res. 1979, 12, 146–151; b) A. de Mei-
jere, F. E. Meyer, Angew. Chem. 1994, 106, 2473–2506;
Angew. Chem. Int. Ed. Engl. 1994, 33, 2379–2411;
c) N. J. Whitcombe, K. K. Hii, S. E. Gibson, Tetrahe-
dron 2001, 57, 7449–7476; d) F. Alonso, I. P. Beletskaya,
M. Yus, Tetrahedron 2005, 61, 11771–11835; e) I. P. Be-
letskaya, A. V. Cheprakov, Chem. Rev. 2000, 100, 3009–
3066; f) A. B. Dounay, L. E. Overman, Chem. Rev.
2003, 103, 2945–2963.
[13] For details, see the Supporting Information.
[14] a) K. Kçhler, R. G. Heidenreich, J. G. E. Krauter, J.
Pietsch, Chem. Eur. J. 2002, 8, 622–631; b) R. G. Hei-
denreich, J. G. E. Krauter, J. Pietsch, K. Kçhler, J. Mol.
Catal. A: Chem. 2002, 182–183, 499–509.
[7] N. Asao, Y. Ishikawa, N. Hatakeyama, Menggenbateer,
Y. Yamamoto, M. Chen, W. Zhang, A. Inoue, Angew.
Chem. 2010, 122, 10291–10293; Angew. Chem. Int. Ed.
2010, 49, 10093–10095.
[8] S. Tanaka, T. Kaneko, N. Asao, Y. Yamamoto, M.
Chen, W. Zhang, A. Inoue, Chem. Commun. 2011, 47,
5985–5987.
[15] For a discussion of the leaching, see; a) L. Durꢃn
Pachꢄn, G. Rothenberg, Appl. Organomet. Chem. 2008,
22, 288–299; b) M. Weck, C. W. Jones, Inorg. Chem.
2007, 46, 1865–1875; c) K. Kçhler, W. Kleist, S. S.
Prçckl, Inorg. Chem. 2007, 46, 1876–1883; d) K.
Kçhler, R. G. Heidenreich, S. S. Soomro, S. S. Prçckl,
Adv. Synth. Catal. 2008, 350, 2930–2936; e) S. S.
Soomro, F. L. Ansari, K. Chatziapostolou, K. Kçhler, J.
[9] a) J. Yu, Y. Ding, C. Xu, A. Inoue, T. Sakurai, M. W.
Chen, Chem. Mater. 2008, 20, 4548–4550; b) M. Haka-
mada, M. Mabuchi, J. Alloys Compd. 2009, 479, 326–
329; c) Z. Zhang, Y. Wang, Z. Qi, W. Zhang, J. Qin, J.
Frenzel, J. Phys. Chem. C 2009, 113, 12629–12636.
[10] a) T. Mizoroki, K. Mori, A. Ozaki, Bull. Chem. Soc.
Jpn. 1971, 44, 581; b) R. F. Heck, J. P. Nolley, J. Org.
Chem. 1972, 37, 2320–2322.
¨
Catal. 2010, 273, 138–146; f) S. Reimann, J. Stotzel, R.
Frahm, W. Kleist, J.-D. Grunwaldt, A. Baiker, J. Am.
Chem. Soc. 2011, 133, 3921–3930.
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Adv. Synth. Catal. 2011, 353, 2927 – 2932