Palladium-Catalyzed Regioselective Aerobic Allylic C?H Oxygenation: Direct Synthesis of α,β-Unsaturated Aldehydes and Allylic Alcohols

Article abstract of DOI:10.1002/adsc.201701324

A protocol for the synthesis of α,β-unsaturated aldehydes and allylic alcohols from simple allylic hydrocarbons with water via palladium-catalyzed functionalization of allylic C?H bonds was described. Molecular oxygen is utilized as the sole oxidant in this oxygenation of terminal alkenes. This protocol features good functional group compatibility, broad substrate scope, and high atom- and step-economy. Moreover, the synthetic utility of this method can be highlighted by its application to the synthesis of ibuprofen, which is a highly potent analgesic. (Figure presented.).

Full text of DOI:10.1002/adsc.201701324

Title: Palladium-Catalyzed Regioselective Aerobic Allylic C-H
Oxygenation: Direct Synthesis of α,β-Unsaturated Aldehydes and
Allylic Alcohols
Authors: Huanfeng Jiang, Chunsheng Li, Jianxiao Li, Meng Li,
Wanqing Wu, Jianhua Liao, and Huoji Chen
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To be cited as: Adv. Synth. Catal. 10.1002/adsc.201701324
Link to VoR: http://dx.doi.org/10.1002/adsc.201701324

10.1002/adsc.201701324
Advanced Synthesis & Catalysis
COMMUNICATION
DOI: 10.1002/adsc.201((will be filled in by the editorial staff))
Palladium-Catalyzed Regioselective Aerobic Allylic C-H
Oxygenation: Direct Synthesis of α,β-Unsaturated Aldehydes
and Allylic Alcohols
Chunsheng Li, Huoji Chen, Jianxiao Li, Meng Li, Jianhua Liao, Wanqing Wu*, and
Huanfeng Jiang*
a
Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou, 510640, People’s Republic of China
Fax: (+86)-020-87112906; phone: (+86)-020-87112906; E-mail: cewuwq@scut.edu.cn, jianghf@scut.edu.cn
Received: ((will be filled in by the editorial staff))
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201######.
of C-O and C=C bonds on the adjacent C-H bonds,
aldehydes and allylic alcohols from simple allylic the allylic ether could undergo further oxidative
Abstract: A protocol for the synthesis of α,β-unsaturated
hydrocarbons with water via palladium-catalyzed
functionalization of allylic C-H bonds was described.
Molecular oxygen is utilized as the sole oxidant in this
oxygenation of terminal alkenes. This protocol features
good functional group compatibility, broad substrate scope,
and high atom- and step-economy. Moreover, the synthetic
utility of this method can be highlighted by its application
to the synthesis of ibuprofen, which is a highly potent
analgesic.
oxygenation in the presence of palladium catalyst to
realize the construction of α,β-unsaturated esters.
Although some work has been reported, further
investigation of the selective aerobic oxidative
functionalization of allylic C-H bonds is still
desirable.
In both bulk and fine chemical industry, direct
conversion of allylic alcohols from terminal alkenes
is a challenging process. Moreover, allylic alcohols
also serve as a significant green synthon in classic
allylic substitution reactions (such as AAA
Keywords: Allylic C-H activation; Molecular oxygen;
Atom- and step-economy
reactions[10]
)
or protecting groups in organic
synthesis.[11-12] Besides, only several examples have
been reported for the construction of alkenyl
The selective oxidative functionalization of C-H
bonds has played a vital role in synthetic chemistry
due to its wide applicablity.[1-2] In recent years,
numerous works have been realized in palladium-
catalyzed selective oxidative functionalization of
allylic C-H bonds of terminal olefins leading to
allylic alkylation,[3] oxygenation,[4] amination,[5]
carbonylation,[6] silylation[7] or dehydrogenation[8].
However, the utilization of stoichiometric oxidant
such as CuII, AgI salts, and benzoquinone to
regenerate the active catalyst usually leads to the
complexity of the reaction system and a decrease in
atom economy. Undoubtedly, with its low cost and
lack of environmentally hazardous byproducts,
molecular oxygen (O2) is an ideal oxidant in this
aldehydes and allylic alcohols from alkenes,[13,
14]
which have confronted with some limitations such as
low chemo-, stereo-, and regioselectivity and low
yields. Herein, we present an atom- and step-
economic strategy for the synthesis of alkenyl
aldehydes and allylic alcohols via palladium-
catalyzed selective aerobic allylic C-H oxygenation
of olefins with water.
Our initial attempts were aimed at studying the
effect of solvents for the allylic oxidative reaction, as
shown in Table 1. In the presence of the Pd(OAc)2
catalyst (10 mol %), the reaction of allylbenzene (1a,
o
0.25 mmol) and H2O (0.25 mL) in MeNO2 at 100 C
novel oxidative functionalization of allylic C-H
5e, 5g]
bonds process.[5b,
In recent years, our group
afforded (E)-3-phenyl-2-propenealdehyde (2a) in 6%
GC-yield (Table 1, entry 1). The screening of various
solvents revealed that the solvent played an important
role in this reaction (Table 1, entries 1-5). Only trace
amount of 2a was obtained when toluene was used
(Table 1, entry 2). Moreover, no desired product was
detected in NMP or DMF (Table 1, entries 3 and 4).
demonstrated a selective aerobic allylic oxygenation
for the synthesis of allyic ethers[4h] and α,β-
unsaturated esters.[9]. In those transformations, the
linear allyic ether was generated through the
intermolecular aerobic oxidative allylic oxygenation
of olefins with alcohol. Owing to the activating effect
1
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10.1002/adsc.201701324
Advanced Synthesis & Catalysis
Pleasingly, the best result was obtained when the
reaction was carried out with Pd(OAc)2 in DMSO at
100 C (Table 1, entry 5). Different catalysts and
additives were then investigated in this
transformation. Pd(OAc)2 was superior to other Pd
catalysts (Table 1, entries 5-9). Additionally, the
addition of n-Bu3P and NEt3, as well as inorganic
base retarded this transformation (Table 1, entries 10-
12). Besides, this reaction did not occur without the
palladium catalyst (Table 1, entry 13).
However, terminal alkyl olefins, such as 1-octene
failed to give the desired product.
Scheme 1. Substrate scope of allylbenzenes [a], [b]
o
Table 1. Optimization of reaction conditions for α,β-
unsaturated aldehydes.[a]
Entry a
Catalyst
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
PdCl2
Solvent
MeNO2
Toluene
DMF
Additive
Yield (%) b
6
1
2
-
-
Trace
n.d.
n.d.
88
3
-
4
DMA
-
[a] Reaction conditions: alkenes 1 (0.25 mmol), H2O (0.25
mL), Pd(OAc)2 (10 mol %) in 2 mL DMSO with O2
balloon at 100 oC for 24 h.
5
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
-
6
-
55
[b]
Isolated yields were given.
7
Pd(PPh3)2Cl2
Pd(TFA)2
Pd(PPh3)4
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
-
-
38
Interestingly, during the investigation of optimal
reaction conditions for the synthesis of α,β-
unsaturated aldehydes, a trace amount of allylic
alcohol 4a was detected. Therefore, efforts were
made to optimize the reaction conditions for the
construction of allylic alcohols. Initially, a range of
acid additives were examined. As shown in Table 3,
when acetic acid was used as the additive, 4a was
obtained in 12% GC yield (Table 3, entry 2), while
the addition of p-toluenesulfonic acid (TsOH) gave a
20% yield of 4a (Table 3, entry 4). Delightfully,
when utilizing hydrochloric acid as the additive, the
yield of 4a increased dramatically. Furthermore, a
variety of palladium catalysts were screened, and
PdCl2 was found to be the optimal choice (Table 3,
entry 6). Subsequently, the examination of different
solvents revealed that DMSO was superior to DMA,
toluene, DMF and 1,4-dioxane (Table 3, entries 9-12).
Finally, lowering the temperature led to the
significant improvement of the product formation,
and the best yield of 4a could be obtained when the
reaction was performed at 100 oC (Table 3, entries 13,
14).
8
-
-
52
9
Trace
12
10
11
12
13
nBu3P
NEt3
Na2CO3
-
Trace
22
n.d.
[a] Reaction conditions: 1a (0.25 mmol), H2O (0.25 mL),
catalyst (10 mol %) in 2 mL of solvents with O2 balloon
at 100 oC for 24 h.
[b] Determined by GC-MS using dodecane as the internal
standard. n.d. = not detected
With the optimized conditions in hand, we turned
to investigate the scope of this transformation. As
shown in Table 2, the corresponding α,β-unsaturated
aldehyde products were obtained in good yields,
regardless of the electron-withdrawing or electron-
donating groups on the phenyl ring of allylbenzenes
(Scheme 1, 2a-2j). Unfortunately, this protocol was
not compatible with the Br-substituted allylbenzenes.
Substituents at the para- and ortho- positions of the
phenyl ring did not affect the efficiency (Scheme 1,
2b and 2i) of this transformation. It is noteworthy that
the alkenyl-substituted propene was tolerated in this
reaction, leading to 2l in good yield. Notably, the
Table 2. Optimization of reaction conditions for allylic
alcohols.[a]
reactions
of
1-allyl-2-thiophene
and
1-
naphthylpropene gave the corresponding products 2m
and 2n in 65% and 67% yields, respectively.
2
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10.1002/adsc.201701324
Advanced Synthesis & Catalysis
Entry a
Catalyst
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
PdCl2
Solvent
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMA
Additive
-
Yield (%) b
moderate to good yields (4f-4h). Additionally, the
alkenyl-substituted
propene
(3n)
smoothly
1
2
5
12
transformed into 4n in medium yield. Moreover, the
reactions of 1-allylnaphthalene (3p) and 2-
allylnaphthalene (3q) proceeded efficiently to give
the desired products 4p and 4q in 72% and 88%
yields, respectively.
HOAc
H2SO4
TsOH
HCl
3
Trace
20
4
5
28
6
HCl
65
Scheme 3. Substrate scope for α-methylstyrenes [a], [b]
7
Pd(TFA)2
Pd(MeCN)2Cl2
PdCl2
HCl
32
8
HCl
29
9
HCl
25
10
11
12
13c
14d
PdCl2
Toluene
DMF
HCl
Trace
27
PdCl2
HCl
1,4-
Dioxane
PdCl2
HCl
16
PdCl2
DMSO
DMSO
HCl
90
PdCl2
HCl
72
[a]
Unless otherwise noted, all reactions were performed
with 3a (0.25 mmol), Pd catalyst (10 mol %), additive (1
equiv) and H2O (0.25 mL) in the indicated solvent (1.0
mL) with O2 balloon at 110 oC for 24 h.
[a]
Unless otherwise noted, all reactions were performed
[b] Isolated yields were given.
with 5 (0.25 mmol), PdCl2 (10 mol %), HCl (1 equiv, 12
mol/L, 0.021 mL) and H2O (0.25 mL) in DMSO (1.0 mL)
with O2 balloon at 100 oC for 24 h.
[c] The reaction was performed at 100 oC.
[d] The reaction was performed at 80 oC.
[b] Isolated yields were given.
Scheme 2. Substrate scope for allylbenzenes [a], [b]
In view of the practicability of this protocol, the
substrate scope was further expanded to different
substituted α-methylstyrenes (Scheme 3). α-
Methylstyrene was investigated which gave a good
yield of product 6a under our optimized reaction
conditions. Moreover, α-methylstyrenes with
functional groups such as F, Cl at the para-position
of the phenyl ring could also convert into
corresponding products 6d-6e in good yields ranging
from 70% to 77%.
Ibuprofen is a pharmaceutical compound that
functions as
a
nonsteroidal anti-inflammatory
analgesic for the treatment of rheumatic and allied
conditions. As an application of our method, we
reported a short four-step synthesis of ibuprofen.
Starting from 1-isobutyl-4-(prop-1-en-2-yl)benzene
(5c), the corresponding allylic alcohol 6c was formed
in excellent yields. Subsequent reduction of 6c
furnished the corresponding alcohol 7 in excellent
yield. Finally, the desired carboxylic acid (8,
ibuprofen) was afforded in 87% yield via the
oxidation process.
[
a]
Unless otherwise noted, all reactions were performed
with 3 (0.25 mmol), PdCl2 (10 mol %), HCl (1 equiv, 12
mol/L, 0.021 mL) and H2O (0.25 mL) in DMSO (1.0 mL)
with O2 balloon at 100 oC for 24 h.
[b] Isolated yields were given.
With the above reaction conditions in hand, we
sought to explore the scope and generality of a
variety of allylbenzenes. Representative results are
summarized in Scheme 2. Generally, the
transformations of substrates with electron-donating
groups (Me, Pr, Bu, and OMe) gave the allylic
alcohol products in good yields. Allylbenzenes with
electron-deficient groups (F, Cl, and CF3) were
converted into the corresponding products in
Scheme 4. Synthesis of Ibuprofen [a]
i
t
3
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10.1002/adsc.201701324
Advanced Synthesis & Catalysis
[a]
down to room temperature, 5 mL of ethyl acetate was
added and DMSO was removed with brine. The residue
was purified by flash chromatography on silica gel to give
the desired product 2a using light petroleum ether/ethyl
acetate (20: 1, v/v) as eluent.
Reaction conditions: (a) 6c (0.5 mmol), Pd/C (50 mg),
MeOH (6 mL), H2 balloon, room temperature, 6 h. (b) 7
(0.5 mmol), pyridinium dichromate (0.6 mmol, 5 equiv),
anhydrous DMF (10 mL), room temperature, 12 h.
Additionally, the reaction of cinnamyl alcohol 3a
under former optimized conditions produced the
aldehyde 2a (Scheme 5), which suggested that
alcohol was the intermediate in the allylic oxidation
process to form alkenyl aldehyde. Moreover, when 3a
was examined under the optimal conditions for allylic
alochols, only a trace amount of 2a was detected.
Based on the previous reports and our observations,
the addition of HCl aq. could suppress the aerobic
alcohol oxidation of cinnamyl alcohols in our
transformation. The possible reasons for this result
are as follows: (i) the coordination of alcohol with
palladium catalyst process would be difficult to occur
due to the formation of oxonium ions; (ii) the rate of
β-H elimination process of aerobic alcohol oxidation
would be reduced dramatically in the presence of
excess proton.[5g, 15]
General methods for synthesis of allylic alcohols.
PdCl2 (0.05 mmol, 12 mg) was mixed with H2O (0.5 mL)/
DMSO (2 mL) in a glass vial or round-bottom flask
equipped with a magnetic stirring bar. Then, allylbenzene
(3a; 0.5 mmol, 59 mg) and HCl (1.0 equiv) was added. The
o
mixture was stirred with an oxygen balloon at 100 C for
24 h. After cooling down to room temperature, 5 mL of
ethyl acetate was added and the DMSO was removed with
brine. The residue was purified by flash chromatography
on silica gel to give the desired product 4a using light
petroleum ether/ethyl acetate (10: 1, v/v) as eluent.
Acknowledgements
The authors thank the National Program on Key Research
Project (2016YFA0602900), the National Natural Science
Foundation of China (21420102003 and 21672072), and the
Fundamental Research Funds for the Central Universities
(2015ZY001 and 2017ZD062) for financial support.
Scheme 5. Control Experiment
References
[1] a) T. W. Lyons, M. S. Sanford, Chem. Rev. 2010, 110,
1147. b) D. Balcells, E. Clot, O. Eisenstein, Chem. Rev.
2010, 110, 749. c) J. Wencel-Delord, T. Drge, F. Liu, F.
Glorius. Chem. Soc. Rev. 2011, 40, 4740. d) L.
Ackermann, Chem. Rev. 2011, 111, 1315. e) O.
Baudoin, Acc. Chem. Res. 2017, 50, 1114. f) Y.-F.
Liang, N. Jiao, Acc. Chem. Res., 2017,
DOI:10.1021/acs.accounts.7b00108. f) W. Wu, H.
Jiang, Acc. Chem. Res. 2012, 45, 1736.
In summary, we have successfully developed a
palladium-catalyzed allylic oxidation of terminal
olefins with water under atmospheric pressure of
oxygen. In this process, water was used as
nucleophilic reagent and oxygen source for direct
hydroxylation of an allylic C-H bond. This method
provides a new efficient and green route for accessing
synthetically useful α,β-unsaturated aldehydes and
highly valuable allylic alcohols from simple allylic
hydrocarbons.
[2] a) B. M. Trost, M. L. Crawley, Chem. Rev. 2003, 103,
2921. b) J. Thomas, F. Peter, Chem. Eur. J. 2009, 15,
9632. c) C. J. Engelin, F. Peter, Molecules, 2011, 16,
951. d) H. Li, B.-J. Li, Z.-J. Shi, Catal. Sci. Technol.
2011, 1, 191. e) F. Liron, J. Oble, M. M. Lorion, G.
Poli, Eur. J. Org. Chem. 2014, 5863.
[3] For allylic C-H alkylation, see: a) A. K. Persson, J.-E.
Bäckvall, Angew. Chem., Int. Ed. 2010, 49, 4624. b) D.
F. Taber, C. G. Nelson, J. Org. Chem. 2010, 76, 1874.
c) H. Jiang, W. Yang, H. Chen, J. Li, W. Wu, H. Jiang,
Chem. Commun. 2014, 50, 7202. d) Y. Nishikawa, S.
Kimura, Y. Kato, N. Yamazaki, O. Hara, Org. Lett.
2015, 17, 888. e) C. C. Pattillo, I. I. Strambeanu, P.
Calleja, N. A. Vermeulen, T. Mizuno, M. C. White, J.
Am. Chem. Soc. 2016, 138, 1265. f) H.-C. Lin, P.-S.
Wang, Z.-L. Tao, Y.-G. Chen, Z.-Y. Han, L.-Z. Gong,
J. Am. Chem. Soc. 2016, 138, 14354. g) L.-L. Li, Z.-L.
Tao, Z.-Y. Han, L.-Z. Gong, Org. Lett. 2017, 19, 102.
Experimental Section
General Procedure for Preparation of Alkenyl
aldehydes.
Pd(OAc)2 (0.05 mmol, 12 mg) was mixed with H2O (0.5
mL)/DMSO (2 mL) in a glass vial or round-bottom flask
equipped with a magnetic stirring bar. Then, allylbenzene
(1a; 0.5 mmol, 59 mg) was added. The mixture was stirred
[4] For allylic C-H oxygenation, see: a) M. S. Chen, M. C.
White, J. Am. Chem. Soc. 2004, 126, 1346; b) M. S.
Chen, N. Prabagaran, N. A. Labenz and M. C. White, J.
Am. Chem. Soc. 2005, 127, 6970. c) N. A. Vermeulen,
o
with an oxygen balloon at 100 C for 24 h. After cooling
4
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10.1002/adsc.201701324
Advanced Synthesis & Catalysis
J. H. Delcamp, M. C. White, J. Am. Chem. Soc. 2010,
Qi, Z. Deng H. Jiang, Tetrahedron 2014, 70, 1516. e)
Y. Suzuki, B. Sun, K. Sakata, T. Yoshino, S.
Matsunaga M. Kanai, Angew. Chem. Int. Ed. 2015, 54,
9944. f) Z. Deng, J. Wei, L. Liao, H. Huang X. Zhao,
Org. Lett. 2015, 17, 1834. g) A. Bunescu, Q. Wag J.
Zhu, Angew. Chem. Int. Ed. 2015, 54, 3132.
132, 11323. d) L. T. Pilarski, P. G. Janson, K. J. Szabó,
J. Org. Chem. 2011, 76, 1503. e) H. Chen, H. Jiang, C.
Cai, J. Dong, W. Fu, Org. Lett. 2011, 13, 992. f) P.-S.
Wang, P. Liu, Y.-J. Zhai, H.-C. Lin, Z.-Y. Han, L.-Z.
Gong, J. Am. Chem. Soc. 2015, 137, 12732. g) S. E.
Ammann, W. Liu, M. C. White, Angew. Chem. Int. Ed.
2016, 55, 9571. h) C. Li, M. Li, J. Li, J. Liao, W. Wu,
H. Jiang, J. Org. Chem. 2017, 82, 10912.
[11] a) L. Huang, Q. Wang, J. Qi, X. Wu, K. Huang H.
Jiang, Chem. Sci. 2013, 4, 2665. b) Q. Wang, L.
Huang, X. Wu H. Jiang, Org. Lett. 2013, 15, 5940. c)
J. Liao, Z. Zhang, X. Tang, W. Wu, W. Guo H. Jiang,
J. Org. Chem. 2015, 80, 8903. d) M. Zheng, P. Chen,
W. Wu H. Jiang, Chem. Commun. 2016, 52, 84 e) J.
Liao, Z. Zhang, X. Tang, W. Wu, H. Jiang, J. Org.
Chem. 2016, 81, 1304.
[5] For allylic C-H amination, see: a) K. J. Fraunhoffer, M.
C. White, J. Am. Chem. Soc. 2007, 129, 7274. b) L.
Wu, S. Qiu, G. Liu, Org. Lett. 2009, 11, 2707. c) Y.
Shimizu, Y. Obor Y. Ishii, Org. Lett. 2010, 12, 1372. d)
C. Jiang, D. J. Covell, A. F. Stepan, M. S. Plummer, M.
C. White, Org. Lett. 2012, 14, 1386. e) H. Chen, W.
Yang, W. Wu H. Jiang, Org. Biomol. Chem. 2014, 12,
3340. f) C. C. Pattillo, I. I. Strambeanu, P. Calleja, N.
A. Vermeulen, T. Mizuno M. C. White, J. Am. Chem.
Soc. 2016, 138, 1265. g) C. Li, J. Li, Y. An, J. Peng, W.
Wu, H. Jiang, J. Org. Chem. 2016, 81, 12189. g) Y.-G.
Li, L. Li, M.-Y. Yang, G. He, E. A. B. Kantchev, J.
Org. Chem. 2017, 82, 4907.
[12] a) A. Wzorek, B. Gawdzik, W. Gladkowski, M.
Urbaniak, A. Baranska, M. Malinska, K. Wozniak, K.
Kempinska J. Wietrzyk, J. Mol. Struct. 2013, 1047,
160. b) K. Fabio, C. Guillon, C. J. Lacey, S.-F. Lu, N.
D. Heindel, C. F. Ferris, M. Placzek, G. Jones, M. J.
Brownstein, N. G. Simon, Bioorg. Med. Chem. 2012,
20, 1337. c) A. Knezevic, G. Landek, I. Dokli V.
Vinkovic, Tetrahedron: Asymmetry 2011, 22, 936. d)
N. Nishina Y. Yamamoto, Tetrahedron, 2009, 65,
1799.
[6] For allylic C-H carbonylation, see: H. Chen, C. Cai, X.
Liu, X. Li, H. Jiang, Chem. Commun. 2011, 47, 12224.
[7] For allylic C-H silylation, see: J. M. Larsson, T. S. N.
[13] R. Tomita, K. Mantani, A. Hamasaki, T. Ishida M.
Zhao, K. J. Szabó, Org. Lett. 2011, 13, 1888.
Tokunaga, Chem. Eur. J. 2014, 20, 9914.
[8] N. Iqbal, S. Choi, E. Kim E. J. Cho, J. Org. Chem.
2012, 77, 11383.
[14] a) J. Muzart, Tetrahedron Lett. 1987, 28, 4665. b) S.
Uemura and S. R. Patil, Tetrahedron Lett. 1982, 23,
4353. c) C. Rav-Acha, E. Choshen S. Sarel, Helv.
Chim. Acta. 1986, 69, 1728.
[9] Yang, W.; Chen, H.; Li, J.; Li, C.; Wu, W. Jiang, H.
Chem. Commun. 2015, 51, 9575.
[15] For the mechanism of Pd(OAc)2/DMSO-catalyzed
aerobic alcohol oxidation, see: B. A. Steinhoff, S. S.
Stahl, J. Am. Chem. Soc. 2006, 128, 4348.
[10] a) B. Sundararaju, M. Achard C. Bruneau, Chem. Soc.
Rev. 2012, 41, 4467. b) G. Chen, S. Wu, H. Liu, H.
Jiang Y. Li, Green Chem. 2013, 15, 230. c) Z. Zhang,
L. Ouyang, W. Wu, J. Li, Z. Zhang H. Jiang, J. Org.
Chem. 2014, 79, 10734. d) J. Li, S. Yang, W. Wu, C.
.
5
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10.1002/adsc.201701324
Advanced Synthesis & Catalysis
COMMUNICATION
Palladium-Catalyzed
Regioselective
Aerobic
Allylic C-H Oxygenation: Direct Synthesis of α,β-
Unsaturated Aldehydes and Allylic Alcohols
Adv. Synth. Catal. Year, Volume, Page – Page
Chunsheng Li, Huoji Chen, Jianxiao Li, Meng Li,
Jianhua Liao, Wanqing Wu*, and Huanfeng Jiang*
6
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