Iron chloride/4-acetamido-TEMPO/sodium nitrite-catalyzed aerobic oxidation of primary alcohols to the aldehydes

Article abstract of DOI:10.1002/adsc.200900662

A variety of 4-substituted 2,2,6,6-tetramethylpiperidyl-1-oxy (TEMPO) derivatives has been screened for their ability in the oxidation of primary alcohols to the aldehydes with dioxygen under mild conditions. An evaluation of the efficiency of these 4-substituted TEMPO derivatives in the alcohol oxidation may allow an insight into the effect of the structural variations of TEMPO on the oxidation of alcohols, which should facilitate catalyst design and screening efforts. Based on the screening results of 4-substituted TEMPO derivatives, the catalyst comprised of 4-acetamidoTEMPO, iron chloride and sodium nitrite, has been developed for the highly efficient oxidation of a wide range of primary alcohols including primary aliphatic alcohols to the corresponding aldehydes under mild conditions.

Full text of DOI:10.1002/adsc.200900662

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DOI: 10.1002/adsc.200900662
Iron Chloride/4-Acetamido-TEMPO/Sodium Nitrite-Catalyzed
Aerobic Oxidation of Primary Alcohols to the Aldehydes
Weili Yin,a,c Changhu Chu,a,c Qiongqiong Lu,a Jianwei Tao,a Xinmiao Liang,a,b,*
and Renhua Liua,*
a
School of Pharmacy, East China University of Science and Technology, Shanghai 200237, Peopleꢀs Republic of China
Fax : (+86)-21-6425-0627; phone: (+86)-21-6425-0627; e-mail: liurh@ecust.edu.cn
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Peopleꢀs Republic of China
b
Fax : (+86)-411-8437-9519; phone: (+86)+21-8437-9539; e-mail: liangxm@dicp.ac.cn
These authors contibuted equally to this work.
c
Received: September 23, 2009; Revised: November 24, 2009; Published online: December 22, 2009
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/adsc.200900662.
Abstract: A variety of 4-substituted 2,2,6,6-tetrame-
thylpiperidyl-1-oxy (TEMPO) derivatives has been
screened for their ability in the oxidation of pri-
mary alcohols to the aldehydes with dioxygen
under mild conditions. An evaluation of the effi-
ciency of these 4-substituted TEMPO derivatives in
the alcohol oxidation may allow an insight into the
effect of the structural variations of TEMPO on the
oxidation of alcohols, which should facilitate cata-
lyst design and screening efforts. Based on the
screening results of 4-substituted TEMPO deriva-
tives, the catalyst comprised of 4-acetamido-
TEMPO, iron chloride and sodium nitrite, has been
developed for the highly efficient oxidation of a
wide range of primary alcohols including primary
aliphatic alcohols to the corresponding aldehydes
under mild conditions.
Notably, a few examples that aimed at oxidative con-
version of primary alcohols to the aldehydes with O2
were reported.[4] However, most reported catalyst sys-
tems for the aerobic oxidation of alcohols require
toxic metals or expensive transition metals such as
palladium[5,6], rhodium or ruthenium[7]. In particular,
for pharmaceuticals, fragrances and food additives,
these directly human body-related compounds, have
been severely restricted in their content of toxic
metals.
In this context, we have recently developed a tran-
sition metal-free TEMPO-based catalyst for the aero-
bic oxidation of a wide range of alcohols.[8] However,
one limitation of the metal-free catalysis is that pri-
mary aliphatic alcohols are oxidized with only moder-
ate selectivity in favor of the formation of aldehydes.
Subsequent optimization of our initial catalytic
system led to an improved and greener protocol,
whereby primary alcohols were selectively oxidized to
the corresponding aldehydes in high yields using HCl
in place of molecular bromine, but the optimized
system required a high TEMPO loading to accom-
plish the oxidation.[9] On the other hand, the transi-
tion metal-catalyzed aerobic oxidation of alcohols has
Keywords: aerobic oxidation; iron chloride; pri-
mary alcohols; sodium nitrite; TEMPO
Aldehydes are useful compounds in the synthesis of been a field of intensive research due to the inherent
fine chemicals such as pharmaceuticals, fragrances or advantages of transition metals in dioxygen activation.
food additives.[1] The controlled oxidation of primary Therefore, we are also interested in the discovery and
alcohols is one of the most important approaches to development of an innovative transition metal cata-
preparation of aldehydes. Recent major efforts in the lyst system for the aerobic oxidation of alcohols, espe-
oxidation of alcohols to carbonyl compounds have cially for oxidative conversion of primary alcohols to
been devoted to the discovery and development of aldehydes. A key criterion was that the metal would
catalytic routes using O2 or H2O2 as the terminal oxi- be cheap, green, and easily available. Iron is a gener-
dant to meet both economic and environmental de- ally accepted green metal, and ironACTHNUGTRNEUNG(III) salts are ex-
mands.[2] Among them, interest in the aerobic oxida- tremely cheap and readily available. We have report-
tion of alcohols utilizing TEMPO-based (2,2,6,6-tetra- ed that FeCl3 in combination with TEMPO and
methylpiperidyl-1-oxy) catalysts has been increasing.[3] NaNO2 was able to oxidize a wide range of alcohols
Adv. Synth. Catal. 2010, 352, 113 – 118
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Weili Yin et al.
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under mild conditions with dioxygen.[10] However, pri- stituted TEMPOs for their ability in the oxidation re-
mary aliphatic alcohols remained elusive. This prob- action. As shown in Table 1, all the 4-substituted
lem was probably attributed to the catalytic activity TEMPOs employed provided relatively high selectivi-
of TEMPO, which was not high enough to selectively ties under the conditions of our screen. 4-Hydroxy-
oxidize primary aliphatic alcohols to the aldehydes. TEMPO also provided 99% selectivity, but its conver-
Based on the FeCl3/TEMPO/NaNO2 catalyst system sion is relatively low and it is known to be susceptible
and a systematic appraisal of 4-substituted TEMPOs, to degradation under oxidative conditions. Although
we report here an improved catalytic system that is the 4-substituent groups of TEMPOs are distant from
À
able to efficiently oxidize a variety of primary alco- the oxidative active center (N O moiety) of TEMPO,
hols to the aldehydes under mild conditions using 4- 4-substituent groups on TEMPOs have a distinct
acetamido-TEMPO in place of TEMPO.
impact on the catalytic activity of TEMPO for alcohol
The investigation began with 2-ethylhexanol as a oxidation, which exceeded our expectations. Electron-
prototypical substrate by screening a variety of 4-sub- withdrawing groups on TEMPO were considered to
Table 1. Catalytic aerobic oxidation of 2-ethylhexanol in the presence of the 4-substituted TEMPOs.[a]
Entry 4-Substituted TEMPO Time
[h]
Conv.
[%][b]
Select.
[%][b]
Entry 4-Substituted
TEMPO
Time
[h]
Conv.
[%][b]
Select.
[%][b]
1
2
2
2
81
86
90
91
10
11
2
2
59
85
98
92
3
2
90
91
12
2
82
94
4
5
6
2
2
2
81
85
81
92
91
92
13
14
15
2
2
2
79
86
71
91
91
90
7
2
89
90
16
2
81
92
8
9
2
2
87
75
96
85
17
18
2
2
92
49
98
99
[a]
[b]
Aerobic oxidation conditions are as follows: alcohol (2 mmol), NaNO2 (0.16 mmol), FeCl3 (0.10 mmol), 4-substituted
TEMPOs (0.10 mmol), C2H4Cl2 (10 mL), 0.4 MPa O2, room temperature.
Conversion and selectivities are based on gas chromatography (GC) with area normalization.
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Iron Chloride/4-Acetamido-TEMPO/Sodium Nitrite-Catalyzed Aerobic Oxidation
Table 2. Catalytic aerobic oxidation of primary alcohols in the presence of 4-acetamido-TEMPO, FeCl3 and NaNO2.[a]
Entry
Substrate
Product
Cat. [%]
Time [h]
Conv. [%][b]
Select. [%][b]
Yield [%][d]
1
2
3
2
3
4
3
100
100
100
99
93
90
90
93
85
11
5
4[c]
5
1
3
1
8
100
100
100
>99
98
87
89
86
23
5
6
>99
7
8
9
3
10
10
5
100
100
100
89
–
0.1
0.5
>99
96
87
92
10
0.5
5
100
98
93
11
12
13
0.5
1
5
100
100
100
>99
>99
94
99
94
89
9
3
12
14
1
12
100
95
94
15[c]
16
2
5
8
100
100
92
94
87
94
0.5
17
0.5
0.1
10
14
100
100
>99
>99
93
88
18[e]
[a]
Aerobic oxidation conditions are as follows: alcohol (5 mmol), NaNO2 (0.40 mmol), FeCl3 (0.25 mmol), 4-acetamido-
TEMPO (0.005–0.15 mmol), C2H4Cl2 (10 mL), 0.4 MPa O2, 508C.
Conversions and selectivities are based on gas chromatography (GC) with area normalization.
1 mL CH3COOH was added.
Isolated yields.
0.4 MPa air in place of O2.
[b]
[c]
[d]
[e]
have beneficial effects on the catalytic activity of groups on acetate can also impact on the catalytic ac-
TEMPO.[11] Interestingly, we observed that such an tivity of the TEMPOs. For example, 4-TEMPO-yl
electronic effect of substituent groups on TEMPOꢀs chloroacetates have a higher catalytic activity than 4-
catalytic activity could also exist at farther distances TEMPO-yl acetate (entries 11 and 12 vs. 10). Al-
from substituent groups to the catalytic activity center though individual examples of 4-substituted TEMPOs
of TEMPO. For 4-TEMPO-yl acetates, chlorine have occasionally been used in the alcohol oxidations,
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Weili Yin et al.
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the systemic appraisal of 4-substituted TEMPOs for plished with high selectivity under addition of a small
their ability to alcohol oxidation has not been report- quantity of acetic acid. Acetic acid was envisioned to
ed previously.
serve a specific purpose, namely to neutralize the
Having examined
a
variety of 4-substituted basic pyridine, to enable the catalyst system to oper-
TEMPOs, we selected 4-acetamido-TEMPO in com- ate well. When air was used in place of pure oxygen
[12]
bination with FeCl3 and NaNO2 as the catalyst to and benzylic alcohol was used as the substrate, we ob-
examine the range of primary alcohols to which this tained equally high isolated yields the reactions vary-
catalytic oxidation could be applied with dioxygen. ing only in a slightly lower conversion rate (Table 2,
After systematic investigation and optimization of the entry 18 vs. entry 8). Overall, when all the facets of
reaction conditions (temperature, oxygen, pressure, this new oxidation system are considered, the use of
and amount of the catalyst), we developed a highly inexpensive and green FeCl3 in combination with 4-
efficient and green aerobic oxidation of a wide range acetamido-TEMPO and NaNO2 and dioxygen as re-
of primary alcohols to the aldehydes. Several features agents rendered the oxidation very attractive for po-
of this catalytic system are worth noting. As revealed tential applications on an industrial scale in the prepa-
in Table 2, a wide variety of benzylic primary alcohols, ration of fine chemicals.
which contain electron-donating and electron-with-
In conclusion, a variety of 4-substituted TEMPOs
drawing groups, were completely converted into the has been systemically estimated for their ability in al-
desired benzaldehydes in high isolated yields (en- cohol oxidation and specific features of their catalytic
tries 9–14, 16 and 17). The electronic properties of the activities have been revealed, which should facilitate
substituents on the benzene ring, whether electron- catalyst design and screening efforts. We have further
donating groups or electron-withdrawing groups, have disclosed that the 4-acetamido-TEMPO/FeCl3/NaNO2
not significantly affected the conversions and selectiv- catalyst could selectively oxidize a broad range of pri-
ities of the oxidations, varying only in the reaction mary alcohols, which may be primary aliphatic alco-
rates: the substrates with electron-donating groups hols or substrates containing carbon-carbon double
(entries 9 and 10) provided a slightly fast reaction bonds or N or S heteroatoms, under mild conditions
compared with those with electron-withdrawing with dioxygen.
groups (entry 12). The catalyst system showed a rela-
tively high catalytic activity for aromatic alcohol oxi-
dation (entries 8–11, 16 and 17). To our pleasure, pri- Experimental Section
mary aliphatic alcohols, which remain elusive in many
aerobic oxidation protocols, were smoothly oxidized General Conditions
to the desired aldehydes with high conversions and
All chemicals were of reagent grade and used as commer-
selectivities (entries 1 and 2). The formation of esters
and/or overoxidation is a recurring problem in the
aerobic oxidation of primary aliphatic alcohols,
whereas this problem did not arise in the newly devel-
oped catalytic system. For instance, oxidations of 1-
octanol and 2-ethylhexanol could achieve 100% con-
version and more than 90% selectivities (entries 1, 2).
2-Phenylethanol and allylic alcohols such as cinnamyl
alcohol could also be converted to the expected alde-
hydes with high selectivity (entries 7 and 5). Interest-
ingly, 2-thiophenemethanol and 4-(methylthio)benzyl
alcohol, which are generally considered as difficult
substrates in most aerobic oxidation systems involving
transition metals because of their strong coordinating
cially supplied without any purification. 1H NMR spectra
were recorded on a Bruker DRX-400 instrument and were
referenced to Me4Si (d=0 ppm) and residual CHCl3 (d=
7.26 ppm). GC analyses for determining the conversions and
selectivities of the reactions were performed on an Agilent
7890N GC system. Experimental procedures and spectro-
scopic data can be found in the Supporting Information.
General Procedure for the Synthesis of 4-Substituted
TEMPOs
Esters: A mixture of 4-OH-TEMPO (1.72 g, 10 mmol), dicy-
clohexylcarbodiimide (DCC) (2.27 g, 11 mmol), 4-dimethyl-
AHCTUNGTREGaNNUN minopyridine (DMAP) (0.12 g, 1 mmol), and the reactant
ability, could also be very smoothly oxidized to the acid (10 mmol) in 15 mL of anhydrous CH2Cl2 was stirred at
room temperature and checked by TLC. After the substrate
was consumed, 50 mL H2O were added, and the mixture
was extracted with ethyl acetate (50 mLꢂ3). The combined
organic layer was dried over anhydrous sodium sulfate and
concentrated under vacuum to obtain crude product, which
was purified by flash chromatography or recrystallization
from mixture solvent (petroleum ether and ethyl acetate) to
afford the desired product. The structures of the final prod-
ucts were confirmed by IR and MS or GC-MS. The prepara-
tion procedure for other TEMPO catalysts can be found in
corresponding aldehydes with high conversions and
selectivities (entries 3 and 6). It is noteworthy that 4-
(methylthio)benzyl alcohol, which bears a sulfide
group that is susceptible to oxidation, was selectively
oxidized into the aldehyde, whereas the sulfide group
remained unreacted. The selectivity may be of great
interest in synthetic organic chemistry. In the case of
3-pyridylmethyl and 2-pyridylmethyl substrates (en-
tries 4 and 15), the oxidative conversions from alco-
hols to the expected aldehydes could also be accom- the Supporting Information.
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Iron Chloride/4-Acetamido-TEMPO/Sodium Nitrite-Catalyzed Aerobic Oxidation
Sheldon, Org. Biomol. Chem. 2003, 1, 3232–3237; j) F.
General Procedure for 4-Acetamido-TEMPO-
Catalyzed Aerobic Oxidation of Alcohols
Minisci, F. Recupero, A. Cecchetto, C. Gambarotti, C.
Punta, R. Faletti, R. Paganelli, G. F. Pedulli, Eur. J.
Org. Chem. 2004, 109–119; k) S. Velusamy, A. Sriniva-
san, T. Punniyamurthy, Tetrahedron Lett. 2006, 47, 923–
926; l) N. Jiang, A. Ragauskas, J. Org. Chem. 2006, 71,
7087–7090; m) N. Lu, Y. Lin, Tetrahedron Lett. 2007,
48, 8823–8828; n) Y. Xie, W. Mo, D. Xu, Z. Shen, N.
Sun, B. Hu, X. Hu, J. Org. Chem. 2007, 72, 4288–4291;
o) B. Karimi, A. Biglari, J. M. Clark, V. Budarin,
Angew. Chem. 2007, 119, 7348–7351; Angew. Chem.
Int. Ed. 2007, 46, 7210–7213; p) P. J. Figiel, M. Leskelꢅ,
T. Repo, Adv. Synth. Catal. 2007, 349, 1173–1179; q) S.
Manner, S. K. Alamsetti, G. Sekar, Adv. Synth. Catal.
2007, 349, 2253–2258; r) L. Liu, J. Ma, Y. Wei, J. Mol.
Catal. A: Chem. 2008, 291, 1–4; s) G. Yang, W. Zhu, P.
Zhang, H. Xue, W. Wang, J. Tian, M. Song, Adv. Synth.
Catal. 2008, 350, 542–546; t) J. Piera, J.-E. Bꢅckvall,
Angew. Chem. 2008, 120, 3558–3576; Angew. Chem.
Int. Ed. 2008, 47, 3506–3523; u) D. E. Bergbreiter, J. H.
Tian, C. Hongfa, Chem. Rev. 2009, 109, 530–582; v) X.
He, Z. Shen, W. Mo, N. Sun, B. Hu, X. Hu, Adv. Synth.
Catal. 2009, 351, 89–92.
The oxidation of alcohols were carried out in a Teflon-lined
316L stainless steel autoclave (300 mL), equipped with a
magnetic stirrer .Typically, the alcohol (5.0 mmol) and 4-
acetamido-TEMPO were dissolved in dichloroethane
(10 mL). Anhydrous FeCl3 (0.25 mmol) was added, followed
by NaNO2 (0.40 mmol).The resulting mixture was stirred at
an oil-bath temperature of 508C and oxygen pressure of
0.4 MPa. The conversion and selectivity of the reaction were
directly monitored by GC analyses without any purification.
When the reactions were completed, the liquid in the auto-
clave was transferred to a separatory funnel. The organic
phase was washed with saturated aqueous Na2S2O3 solution
to remove the residual oxidant and 4-acetamido-TEMPO.
Then the organic layer was dried over anhydrous Na2SO4
and concentrated and further purified by flash chromatogra-
phy to afford the desired product.
Acknowledgements
[4] a) P. Gamez, I. W. C. E. Arends, J. Reedijk, R. A. Shel-
don, Chem. Commun. 2003, 2414–2415; b) I. E. Markꢃ,
A. Gautier, R. Dumeunier, K. Doda, F. Philippart,
S. M. Brown, C. J. Urch, Angew. Chem. 2004, 116,
1614–1617; Angew. Chem. Int. Ed. 2004, 43, 1588–
1591; c) P. Gamez, I. W. C. E. Arends, R. A. Sheldon, J.
Reedijk, Adv. Synth. Catal. 2004, 346, 805 À811; d) M.
Gilhespy, M. Lok, X. Baucherel, Chem. Commun.
2005, 1085–1086; e) N. Jiang, A. Ragauskas, Org. Lett.
2005, 7, 3689–3692; f) D. Geiblmeir, W. G. Jary, H.
Falk, Monatsh. Chem. 2005, 136, 1591–1592; g) S. Strie-
gler, Tetrahedron 2006, 62, 9109–9114.
[5] For reviews on Pd-catalyzed aerobic oxidations, see:
a) J. Muzart, Tetrahedron 2003, 59, 5789–5816; b) S. S.
Stahl, Angew. Chem. 2004, 116, 3480–3501; Angew.
Chem. Int. Ed. 2004, 43, 3400–3420; c) S. S. Stahl, Sci-
ence 2005, 309, 1824–1826; d) D. R. Jensen, M. S.
Sigman, Acc. Chem. Res. 2006, 39, 221–229; e) K. M.
Gligorich, M. S. Sigman, Angew. Chem. 2006, 118,
6764–6767; Angew. Chem. Int. Ed. Angew. Chem. Int.
.Ed. 2006, 45, 6612–6615.
[6] For palladium-catalyzed aerobic alcohol oxidation, see:
a) K. P. Peterson, R. C. Larock, J. Org. Chem. 1998, 63,
3185–3189; b) T. Nishimura, T. Onoue, K. Ohe, S.
Uemura, J. Org. Chem. 1999, 64, 6750–6755; c) G.-J.
ten Brink, I. W. C. E. Arends, R. A. Sheldon, Science
2000, 287, 1636–1639; d) S. S. Stahl, J. L. Thorman,
R. C. Nelson, M. A. Kozee, J. Am. Chem. Soc. 2001,
123, 7188–7189; e) G.-J. ten Brink, I. W. C. E. Arends,
R. A. Sheldon, Adv. Synth. Catal. 2002,344, 355–369;
f) B. A. Steinhoff, S. R. Fix, S. S. Stahl, J. Am. Chem.
Soc. 2002, 124, 766–767; g) B. A. Steinhoff, S. S. Stahl,
Org. Lett. 2002, 4, 4179–4181; h) M. J. Schultz, C. C.
Park, M. S. Sigman, Chem. Commun. 2002, 3034–3045;
i) Y. Uozumi, R. Nakao, Angew. Chem. 2003, 115, 204–
207; Angew. Chem. Int. Ed. 2003, 42, 194–197; j) D. R.
Jensen, M. J. Schultz, J. A. Mueller, M. S. Sigman,
Angew. Chem. 2003, 115, 3940–3943; Angew. Chem.
Int. Ed. 2003, 42, 3810–3813; k) T. Iwasawa, M. Toku-
This work was supported by grants from the National High
Technology Research and Development Program of China
(863 Program) (No. 2008AA06Z306) and the National Natu-
ral Science Foundation of China (No. 20572110).
References
[1] a) R. A. Sheldon, I. W. C. E. Arends , A. Dijksman,
Catal. Today 2000, 57, 157–166; b) T. Mallat, A.
Baiker, Catal. Today 1994, 19, 247–283; c) M. Musawir,
P. N. Davey, G. Kelly , I. V. Kozhevnikov, Chem.
Commun. 2003, 1414–1415.
[2] a) I. P. Skibida, A. M. Sakharow, Catal. Today 1996, 27,
187–193; b) I. E. Markꢃ, P. R. Giles, M. Tsukazaki,
S. M. Brown, C. J. Urch, Science 1996,274, 2044–2046;
c) I. E. Markꢃ, P. R. Giles, M. Tsukazaki, I. Chellꢄ-
Regnaut, A. Gautier, S. M. Brown, C. J. Urch, J. Org.
Chem. 1999,64, 2433–2439; d) R. Noyori, M. Aoki, K.
Sato, Chem. Commun. 2003, 1977–1986; e) T. Mallat,
A. Baiker, Chem. Rev. 2004, 104, 3037–3058; f) N.
Jiang, A. J. Ragauskas, Tetrahedron Lett. 2005, 46,
3323–3326; g) S. Velusamy, A. V. Kumar, R. Saini, T.
Punniyamurthy, Tetrahedron Lett. 2005, 46, 3819–3822.
[3] a) F. M. Semmelhack, C. R. Schmidt, D. A. Cortes, C. S.
Chou, J. Am. Chem. Soc. 1984, 106, 3374–3376; b) B.
Betzemeier, M. Cavazzini, S. Quici, P. Knochel, Tetra-
hedron Lett. 2000, 41, 4343–4346; c) A. Cecchetto, F.
Fontana, F. Minisci, F. Recupero, Tetrahedron Lett.
2001, 42, 6651–6653; d) R. Ben-Daniel, P. Alsters, R.
Neumann, J. Org. Chem. 2001, 66, 8650–8653; e) W.
Adam, C. R. Saha-Mçller, P. A. Ganeshpure, Chem.
Rev. 2001, 101, 3499–3548; f) I. A. Ansari, R. Gree,
Org. Lett. 2002, 4, 1507–1509; g) R. A. Sheldon,
I. W. C. E. Arends, G.-J. ten Brink, A. Dijksman, Acc.
Chem. Res. 2002, 35, 774–781; h) G. Ragagnin, B. Bet-
zemeier, S. Quici, P. Knochel, Tetrahedron 2002, 58,
3985–3991; i) A. Dijksman, I. W. C. E. Arends, R. A.
Adv. Synth. Catal. 2010, 352, 113 – 118
ꢁ 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
117

Weili Yin et al.
COMMUNICATIONS
naga, Y. Obora, Y. Tsuji, J. Am. Chem. Soc. 2004, 126,
6554–6555; l) M. J. Schultz, C. P. Goller, M. S. Sigman,
J. Am. Chem. Soc. 2004, 126, 9724–9734; m) K. Mori,
T. Hara, T. Mizugaki, K. Ebitani, K. Kaneda, J. Am.
Chem. Soc. 2004, 126, 10657–10666; n) B. A. Steinhoff,
I. A. Guzei, S. S. Stahl, J. Am. Chem. Soc. 2004, 126,
11268–11278; o) M. J. Schultz, S. S. Hamilton, D. R.
Jensen, M. S. Sigman, J. Org. Chem. 2005, 70, 3343–
3352; p) B. P. Buffin, J. P. Clarkson, N. L. Belitz, A.
Kundu, J. Mol. Catal. A: Chem. 2005, 225, 111–116;
q) M. J. Schultz, R. S. Adler, W. Ziekiewicz, T. Privalov,
M. S. Sigman, J. Am. Chem. Soc. 2005, 127, 8499–8507;
r) M. S. Kwon, N. Kim, C. M. Park, J. S. Lee, K. Y.
Kang, J. Park, Org. Lett. 2005, 7, 1077–1079; s) Z. Hou,
N. Theyssen, A. Brinkmann, W. Leitner, Angew. Chem.
2005, 117, 1370–1373; Angew. Chem. Int. Ed. 2005, 44,
1346–1349; t) B. A. Steinhoff, S. S. Stahl, J. Am. Chem.
Soc. 2006, 128, 4348–4355; u) B. A. Steinhoff, A. E.
King, S. S. Stahl, J. Org. Chem. 2006, 71, 1861–1868;
v) S. Shimazu, T. Uehara, A. Asami, T. Hara, N. Ichiku-
ni, J. Mol. Catal. A: Chem. 2008, 282, 28–33.
Chem. Soc. 2001, 123, 6826–6833; d) G. Csjernyik,
A. H. ꢇll, L. Fadini, B. Pugin, J.-E. Bꢅckvall, J. Org.
Chem. 2002, 67, 1657–1662; e) K. Yamaguchi, N.
Mizuno, Angew. Chem. 2002, 114, 4720–4724; Angew.
Chem. Int. Ed. 2002, 41, 4538–4542; f) B.-Z. Zhan,
M. A. White, T.-K. Sham, J. A. Pincock, R. J. Doucet,
K. V. R. Rao, K. N. Robertson, T. S. Cameron, J. Am.
Chem. Soc. 2003, 125, 2195–2199; g) H. Shimizu, S.
Onitsuka, H. Egami, T. Katsuki, J. Am. Chem. Soc.
2005, 127, 5396–5413; h) H. Egami, S. Onitsuka, T.
Katsuki, Tetrahedron Lett. 2005, 46, 6049–6052; i) K.
Kaneda, K. Ebitani, T. Mizugaki, K. Mori, Bull. Chem.
Soc. Jpn. 2006, 79, 981–1016; j) T. Matsumoto, M.
Ueno, J. Kobayashi, H. Miyamura, Y. Mori, S. Kobaya-
shi, Adv. Synth. Catal. 2007, 349, 531–534.
[8] a) R. Liu, X. Liang, C. Dong, X. Hu, J. Am. Chem. Soc.
2004, 126, 4112–4113; b) R. Liu, C. Dong, X. Liang, X.
Wang, X. Hu, J. Org. Chem. 2005, 70, 729–731.
[9] X. Wang, R. Liu, Y. Jin, X. Liang, Chem. Eur. J. 2008,
14, 2679–2685.
[10] N. Wang, R. Liu, J. Chen, X. Liang, Chem. Commun.
2005, 5322–5344.
[11] G. I. Shchukin, V. A. Ryabinin, I. A. Grigor’ev, L. B.
Volodarsky, Zh. Obshch. Khim. 1986, 56, 855–860.
[12] FeCl3 we used was a domestic commercial reagent,
with a purity of >99%. According to atom absorption
spectroscopy, the copper content was 0.0061%.
[7] a) I. E. Markꢃ, P. R. Giles, M. Tsukazaki, I. Chellꢄ-
Regnaut, C. J. Urch, S. M. Brown, J. Am. Chem. Soc.
1997, 119, 12661–12662; b) A. Dijksman, I. W. C. E.
Arends, R. A. Sheldon, Chem. Commun. 1999, 1591–
1592; c) A. Dijksman, A. Marino-Gonzꢆlez, A. Mairata
i Payeras, I. W. C. E. Arends, R. A. Sheldon, J. Am.
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