Room-temperature Cu-catalyzed: N -arylation of aliphatic amines in neat water

Article abstract of DOI:10.1039/c7ob02126g

A room-temperature and PTC-free copper-catalyzed N-arylation of aliphatic amines in neat water has been developed. Using a combination of CuI and 6,7-dihydroquinolin-8(5H)-one oxime as the catalyst and KOH as the base, a wide range of aliphatic amines are arylated with various aryl and heteroaryl halides to give the corresponding products in up to 95% yield.

Full text of DOI:10.1039/c7ob02126g

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Takeharu Haino et al.
Solvent-induced emission of organogels based on tris(phenylisoxazolyl)
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DOI: 10.1039/C7OB02126G
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Room-Temperature Cu-Catalyzed N-Arylation of Aliphatic Amines
in Neat Water
Received 00th January 20xx,
Accepted 00th January 20xx
Deping Wang,*a Yanwen Zheng,a Min Yang,b Fuxing Zhang,a Fangfang Mao,a Jiangxi Yu,a and
Xiaohong Xia*b
DOI: 10.1039/x0xx00000x
www.rsc.org/
A room-temperature and PTC-free copper-catalyzed N-arylation of temperatures (25/50 oC). Thus, it is still highly desirable for the
aliphatic amines in neat water has been developed. Using a development of an efficient Cu-catalyst system to promote the
combination of CuI and 6,7-dihydroquinolin-8(5H)-one oxime as N-arylation of aliphatic amines at milder conditions in water.
catalyst, KOH as base, a wide range of aliphatic amines are
In a continuation of our search for cheap, simple, and
arylated with various aryl and heteroaryl halides to give the environmental-friendly catalyst systems for Ullmann type
corresponding products in up to 95% yield.
coupling reactions,11 we herein wish to report a universal
copper-catalyzed N-arylation and heteroarylation of aliphatic
amines at room temperature (25 oC) in neat water.
Cu-catalyzed Ullmann coupling-reaction provides an invaluable
route for the assembly of numerous N-containing compounds
including pharmaceuticals, agrochemicals, and natural
products.1 Over the past decades, several classes of ligands,2-3
most notably diamines,4 amino acids,5 β-diketones,6 oxalamide7
were introduced to promote the Cu-catalysed N-arylation of
aliphatic amines with aryl iodides, bromines, and especially
nonactivated chlorides7b-c in high yields at mild reaction
conditions. Despite this progress, expensive, harmful, and
uneasily recoverable organic solvents such as DMSO, DMF,
and NMP are usually required in the most of N-arylation of
amines process.3-7
Table 1 Room-temperature copper-catalyzed amination in neat water: effect of
ligands and bases.a
H
e
M
mo
u
L
e
M
5
l
C I
%
%
l
Nn
ex
H
mo
6
+
I
e
M
H2N
ase
H2 25 o
.
e u v
3 0
i
q
O
b
,
C
,
e
M
e
M
a
3
a
1
a
2
O
O
O
O
N
N
N
N
H
O
H
O
L1
L2
L3
L4
Water is an economical, eco-friendly, and renewable media
in the world.8 In consideration of the emergence of green
chemistry and the wide use of N-containing organic compounds
in many fields have gained increasing attention on the
development of new methods for their synthesis in water.9
Nevertheless, Cu-catalyzed N-arylation of aliphatic amines in
aqueous media have been described rarely.9f-g,9k,9m-n Moreover,
these reactions, to be efficient, usually required high
temperatures (80-130 oC) and/or PTC. Recently, Schmitt et al.10
reported an efficient three-component catalyst system of 10 mol%
Cu(OTf)2, 20 mol% THMD, 10 mol% reducing agent (d-
glucose) for the coupling reactions of aliphatic primary amines
with aryl iodides and bromides in water at much lower
H
N
O
O
H
H
O
N
O
H
N
H
H
L5
L
6
L7
entry
1
2
3
4
5
6
7
8
ligand
--
base
NaOH
NaOH
NaOH
NaOH
NaOH
NaOH
NaOH
NaOH
K2CO3
KOH
yield (%)a
0
L1
L2
L3
L4
L5
L6
L7
L1
75
25
<5
<5
<5
<5
0
32
91
90
9
10
11
a.College of Chemistry and Materials Science, Hengyang Normal University.
Hengyang 421008, Hunan Province, China. E-mail: deping_wang@hynu.edu.cn
b.College of Materials Science and Engineering, Hunan University, Changsha
410082, China. E-mail: xxh@hnu.edu.cn
† Footnotes relating to the title and/or authors should appear here.
Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/x0xx00000x
L1
L1
CsOH
a
Reaction conditions: Ar-I (1.0 mmol), amine (1.5 mmol), 5 mol% CuI, 6 mol%
ligand, base (3.0 mmol), H2O (1.5 mL), Ar, 25 oC, 36 h.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
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Table 2 Room-temperature amination ofaryl/heteroaryl iodides in neat watera
Table 3 CuI-catalyzed amination of aryl and heteroaryl bromides in neat watera
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DOI: 10.1039/C7OB02126G
H
O
mo
mo
u
L1
5
6
l
l
C I
%
%
N
H
O
R1
N
R2
R1
R2
mo
mo
u
I
L1
5
6
l
l
% C
%
N
N
R1
R1
R2
+
I
r
r
A
=
HN
L1
A
N
.
e u v
i KOH
q
3 0
r
r +
r
A
B
HN
N
=
L1
A
.
e u v
i KOH
q
H2 25 o
R2
3 0
O
,
C
H
65 o
O
,
C
2
N
c
C
A
N
O2
e
M
n
n
n
l
C
e
M
O
ex
H
ex
e
x
H
H
N
N
H
N
n
n
H
H
ex
H
ex
H
n
ex
H
N
N
3d, 18 h, 88%
3b, 18 h, 93%
e
3c, 18 h, 95%
M
N
H
H
H
r
B
l
C
3h, 36 h, 87%, 10%[b]
3e, 18 h, 93%
3a, 36 h, 90%
n
n
n
ex
H
ex
H
ex
H
H
N
e
e
M
M
O
N
N
H
N
H
H
PMB
3g, 18 h, 83%
N
N
H
H
3e, 18 h, 92%
3f, 18 h, 90%
O
H
e
M
e
O
O
M
Ph
Ph
4b, 36 h, 87%
4c, 18 h, 90%
4d, 36 h, 81%
n
ex
H
H
N
Ph
N
e
N
H
N
M
e
M
HO
N
H
H
O
N
H
3i, 36 h, 90%
H2N
e
3h, 36 h, 94%
3j, 36 h, 88%
N
M
Ph
F
3C
H
c
l
C
NHA
4f, 36 h, 87%
4e, 36 h, 85%
3s, 18 h, 93%
N
N
H
N
H
l
C
Ph
N
3m, 18 h, 90%
3l, 36 h, 85%
3k, 18 h, 87%
N
N
N
H
H
H
N
O2
H
N
N
N
3t, 18 h, 95%
PMB
3k, 18 h, 90%
4g, 18 h, 86%
H
Ph
H
N
O
H
N
S
N
O2
H
COO
N
O2
e
M
3o, 36 h, 90%
e
M
N
3n, 18 h, 86%
3p, 18 h, 90%
N
N
H
N
e
M
e
O
M
N
S
H
O
N
H
N
N
4i, 18 h, 87%
4j, 18 h, 86%
Ph
N
H
4h, 18 h, 89%
F
3C
a
Reaction conditions: Ar-Br (1.0 mmol), amine (1.5 mmol), 5 mol% CuI, 6 mol%
3q, 18 h, 91%
3r, 36 h, 89%
3s, 18 h, 95%
L1, KOH (3.0 mmol), H2O (1.5 mL), Ar, 65 oC,. b Ar-Cl (1.0 mmol), 100 oC.
H
N
Ph
S
(Table 1, entry 9). Excellent yields of 91% and 90% were
obtained when using other two comparatively stronger bases
of KOH and CsOH, respectively (Table 1, entries 9-10). These
results showed that higher alkalinity favor the formation of the
desired product.
Under optimal conditions, we next set out to examine the
scope of the room temperature C-N cross-coupling reactions.
As shown in Table 2, the room-temperature N-arylation of
kinds of aliphatic amines in neat water proceeded smoothly
with a wide range of aryl iodides in good to excellent yields.
N
N
N
N
H
N
H
3t, 18 h, 93%
3u, 36 h, 92%
3v, 18 h, 89%
H
N
O
e
M
H
N
N
N
N
e
e
M
Ph
N
N
H
S
M
3x, 18 h, 81%
3w, 36 h, 92%
3y, 36 h, 89%
Et
H
N
Et
N
e
O
M
NH
Both electron-donating
(
3h, 3j, 3r, 3z) and electron-
e
M
O
withdrawing (3b 3f, 3p, 3s) substituents were well tolerated
-
4a, 36 h, 0%
3z, 36 h, 78%
for the aryl iodides (78 to 95% yield). The reaction can
accommodate a large number of functional groups, including
ketones, nitrile groups, nitro groups, halides (Cl and Br), and
even free amino, carboxylic acid group, and free hydroxyl
group. More importantly, this catalyst system enabled
a
Reaction conditions: Ar-I (1.0 mmol), amine (1.5 mmol), 5 mol% CuI, 6 mol%
L1, KOH (3.0 mmol), H2O (1.5 mL), Ar, 25 oC.
Initially, the coupling of 1-iodo-3,5-dimethylbenzene with n-
hexylamine in neat water at room temperature was selected as
the model reaction to optimize the ligands and bases (Table 1).
First, in the absence of ligand, no reaction was observed. In
contrast, the reaction provided the desired production in a 75%
yield with the use of 6 mol% 6,7-dihydroquinolin-8(5H)-one
oxime (L1) as ligand. Picolinaldehyde oxime (L2) was also
tested, but only 25% of 3a was isolated. Other ligands (L3-L7)
were poorly active or inactive. Next, by replacing the base with
the relatively weaker base of K2CO3, the yield dropped to 32%
heteroaryl iodides (3t-3y) coupled with a series of aliphatic
amines in excellent yields (81 to 93%). This feature renders the
catalyst system useful for the synthesis of biologically active
molecules bearing heterocycles in water. It should be
particularly noted that a diverse set of aliphatic amines, even in
presence of sensitive substituents (3l, 3r, 3z) or with a strongly
steric hindrance (3k, 3m, 3p, 3u, 3w), were effectively N-
arylated with aryl iodides to provide the corresponding products
in good to excellent yields under the standard conditions. By
2 | J. Name., 2012, 00, 1-3
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2011, 40, 5151; (g) I. P. Beletskaya, A. VV.iewCAhretipclreaOknolinve,
Organometallics, 2012, 31, 7753; (h)DOAI.: 1C0.a1s0i3ta9/sC, 7XO.B0R2i1b2a6sG,
Chem. Sci. 2013, 4, 2301; (i) C. Sambiagio, S. P. Marsden, A.
contrast, the N-arylation of acyclic secondary amines (such as
diethylamine) did not take place under the optimal conditions
and the corresponding product 4a could not be isolated in the
crude reaction mixtures from which the starting aryl iodide
could be almost fully recovered.
J. Blacker, P. C. McGowan, Chem. Soc. Rev., 2014, 43, 3525.
For selected examples, see: (a) H.-J. Cristau, P. P. Cellier, J.-
F. Spindler and M. Taillefer, Chem. Eur. J., 2004, 10, 5607;
(b) Q. Jiang, D. Jiang, Y. Jiang, H. Fu, Y. Zhao, Synlett, 2007,
1836; (c) M. Yang and F. Liu, J. Org. Chem., 2007, 72, 8969;
(d) D. Jiang, H. Fu, Y. Jiang, Y. Zhao, J. Org. Chem., 2007,
72, 672; (e) H. Rao, H. Fu, Y. Jiang and Y. Zhao, J. Org.
Chem., 2005, 70, 8017; (f) H. Rao, Y. Jin, H. Fu, Y. Jiang and
Y. Zhao, Chem. Eur. J., 2006, 12, 3636; (g) X. Zhu, Y. Ma, L.
3
After examining the reactivity of different aryl iodides, we
next studied whether the same catalyst system could be applied
to aryl bromides, which are more economical and widely used
in synthetic intermediates. As illustrated in Table 3, a wide
range of aryl bromides with electron-donating or -withdrawing
substituents coupled with kinds of aliphatic amines smoothly to
give the corresponding products in good to excellent yields (81-
Su, H. Song, G. Chen, D. Liang, Y. Wan, Synthesis, 2006, 23
,
3955; (h) M. Taillefer, N. Xia and A. Ouali, Angew. Chem.
Int. Ed., 2007, 46, 934; (i) J. Mao, J. Guo, H. Song and S. Ji,
Tetrahedron, 2008, 64, 1383; (j) H. Wang, Y. Li, F. Sun, Y.
Feng, K. Jin and X. Wang, J. Org. Chem., 2008, 73, 8639; (k)
P. Suresh and K. Pitchumani, J. Org. Chem., 2008, 73, 9121;
(l) K. L. Jones, A. Porzelle, A. Hall, M. D. Woodrow and N.
C. O. Tomkinson, Org. Lett., 2008, 10, 797; (m) D. Wang, K.
Ding, Chem. Commun., 2009, 1891; (n) C.-Z. Tao, W.-W.
Liu, J.-Y. Sun, Z.-L. Cao, H. Li, Y.-F. Zhang, Synthesis, 2010,
1280; (o) K. Yang, Y. Qiu, Z. Li, Z. Wang, S. Jiang, J. Org.
Chem., 2011, 76, 3151; (p) X. Zhu, L. Su, L. Huang, G. Chen,
J. Wang, H. Song, Y. Wan, Eur. J. Org. Chem., 2009, 635; (q)
D. Che, K. Yang, H. Xiang, S. Jiang, Tetrahedron Lett., 2012,
53, 712; (r) Y. Wang, J. Ling, Y. Zhang, A. Zhang, Q. Yao,
Eur. J. Org. Chem., 2015, 4153; (s) X. Ge, X. Chen, C. Qian,
o
90%) at a moderate temperature of 65 C. The amination of
heteroaryl bromides were also achieved successfully under the
catalyst system in neat water (Table 3, 3t, 4h-4j). In addition,
the amination of less active aryl chlorides was also investigated
by using the coupling of 4-Chloroanisole with n-hexylamine as
a model. The reaction only gave a yield of 10% at 100 oC under
CuI/L1 catalyst system (Table 3, 3h). No significant
improvement was achieved with higher temperature applied.
Conclusions
We have developed a general, eco-friendly, and PTC-free
copper-catalyst system for room-temperature N-arylation of
aliphatic amines in neat water. Using Cu/L1 catalyst system,
the conditions of N-arylation of aliphatic amines are mild,
simple and cheap. Further, in comparison with the use of
stronger base and the moisture sensitive conditions for the Pd-
catalyzed process, this protocol utilized KOH as base and
enabled the arylation process to take place in neat water, which
would make Cu/L1 catalyst system adaptable to industrial
production and to synthesize N-containing bioactive molecules
because of the environmentally friendly and milder reaction
conditions.
S. Zhou, RSC Adv., 2016,
Qian, S. Zhou, RSC Adv., 2016,
6
, 29638; (t) X. Ge, X. Chen, C.
, 58898; (u) X. Ding, M.
6
Huang, Z. Yi, D. Du, X. Zhu, Y. Wan, J. Org. Chem.,
2017, 82, 5416; (v) X. Zhao, Y. She, K. Fang, G. Li, J. Org.
Chem., 2017, 82, 1024.
(a) J. C. Antila, J. M. Baskin, T. E. Barder, S. L. Buchwald, J.
Org. Chem., 2004, 69, 5578; (b) A. Klapars, J. C. Antila, X.
Huang, S. L. Buchwald, J. Am. Chem. Soc., 2001, 123, 7727;
(c) J. C. Antila, A. Klapars, S. L. Buchwald, J. Am. Chem.
Soc., 2002, 124, 11684; (d) A. Klapars, X. Huang and S. L.
Buchwald, J. Am. Chem. Soc., 2002, 124, 7421; (e) P.-F.
Larsson, A. Correa, M. Carril, P.-O. Norrby, C. Bolm, Angew.
4
Chem., 2009, 121, 5801; Angew. Chem. Int. Ed., 2009, 48
5691; (f) P.-F. Larsson, C. Bolm, P.-O. Norrby, Chem. Eur. J.,
2010, 16, 13613.
,
5
6
7
(c) H. Zhang, Q. Cai, D. Ma, J. Org. Chem., 2005, 70, 5164;
(d) D. Ma, Q. Cai, H. Zhang, Org. Lett., 2003,
5, 2453; (e) D.
Acknowledgements
Ma and C. Xia, Org. Lett., 2001, , 2583; (f) D. Ma, Q. Geng,
3
H. Zhang, Y. Jiang, Angew. Chem., Int. Ed. 2010, 49, 1291;
(g) J. Li, Y. Zhang, Y. Jiang, D. Ma, Tetrahedron Lett., 2012,
The authors thank National Natural Science Foundation of
China (No. 21202041 and 51402101), Natural Science
Foundation of Hunan Province (No. 2017JJ2008), the Aid
Programs for Science and Technology Innovative Research
Team in Higher Educational Institutions of Hunan Province,
and the Key Discipline of Hunan Province for their financial
support.
53, 3981; (h) C. Deldaele, G. Evano, ChemCatChem, 2016,
8
,
1319.
(a) A. Shafir, S. L. Buchwald, J. Am. Chem. Soc., 2006, 128
,
8742; (b) B. d. Lange, M. H. Lambers-Verstappen, L. S. d.
Vondervoort, N. Sereinig, R. d. Rijk, A. H. M. d. Vries, J. G.
d. Vries, Synlett, 2006, 18, 3105; (c) A. Shafir, P. A. Lichtor,
S. L. Buchwald, J. Am. Chem. Soc., 2007, 129, 3490. (d) X.
lv and W. Bao, J. Org. Chem., 2007, 72, 3863; (e) N. Xia and
M. Taillefer, Angew. Chem. Int. Ed., 2009, 48, 337.
(a) Y. Zhang, X. Yang, Q. Yao, D. Ma, Org. Lett., 2012, 14
,
3056; (b) W. Zhou, M. Fan, J. Yin, Y. Jiang, D. Ma, J. Am.
Chem. Soc., 2015, 137, 11942; (c) M. Fan, W. Zhou, Y. Jiang,
D. Ma, Org. Lett., 2015, 17, 5934; (d) S. Xia, L. Gan, K.
Wang, Z. Li, D. Ma, J. Am. Chem. Soc., 2016, 138, 13493; (e)
M. Fan, W. Zhou, Y. Jiang, D. Ma, Angew. Chem., Int. Ed.,
2016, 55, 6211; (f) G. G. Pawar, H. Wu, S. De, D. Ma, Adv.
Synth. Catal., 2017, 359, 1631; (g) J. Gao, S. Bhunia, K.
Wang, L. Gan, S. Xia, D. Ma, Org. Lett., 2017, 19, 2809.
(a) U. M. Lindstrçm, Chem. Rev., 2002, 102, 2751; (b) S.
Kobayahi, K. Manabe, Acc. Chem. Res., 2002, 35, 209; (c) N.
Notes and references
1
(a) J. Lindley, Tetrahedron, 1984, 40, 1433; (b) T. Wiglenda,
R. Gust, J. Med. Chem., 2007, 50, 1475.
2
For selected reviews, see: (a) D. Ma, Q. Cai, Acc. Chem. Res.,
2008, 41, 1450; (b) G. Evano, N. Blanchard, M. Toumi,
Chem. Rev., 2008, 108, 3054; (c) F. Monnier, M. Taillefer,
Angew. Chem., 2009, 121, 7088; Angew. Chem., Int. Ed.,
2009, 48, 6954; (d) D. S. Surry, S. L. Buchwald, Chem. Sci.,
8
2010,
2011,
1
, 13; (e) D. S. Surry, S. L. Buchwald, Chem. Sci.,
2
, 27; (f) G. C. Fortman, S. P. Nolan, Chem. Soc. Rev.,
This journal is © The Royal Society of Chemistry 20xx
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Please do not adjust margins
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Page 4 of 4
COMMUNICATION
Journal Name
Akiya, P. E. Savage, Chem. Rev., 2002, 102, 2725; (d) J. M.
DeSimone, Science, 2002, 297, 799; (e) M. Poliakoff, J. M.
View Article Online
DOI: 10.1039/C7OB02126G
Fitzpatrick, T. R. Farren, P. T. Anastas, Science, 2002, 297
,
807; (f) C.-J. Li, Chem. Rev., 2005, 105, 3095; (g) D. G.
Blackmond, A. Armstrong, V. Coombe, A. Wells, Angew.
Chem., 2007, 119, 3872; Angew. Chem. Int. Ed., 2007, 46
3798; (h) S. Minakata, M. Komatsu, Chem. Rev., 2008, 108
,
,
825; (i) C. I. Herrerias, X. Yao, Z. Li, C.-J. Li, Chem. Rev.,
2007, 107, 2546; (j) R. A. Sheldon, Green Chem., 2005,
7
,
267; (k) A. Chanda, V. V. Fokin, Chem. Rev., 2009, 109, 725;
(l) R. N. Butler, A. G. Coyne, Chem. Rev., 2010, 110, 6302.
(a) C. Mukhopadhyay, P. K. Tapaswi, R. J. Butcher, Org.
9
Biomol. Chem., 2010, 8, 4720; (b) F.-F. Yong, Y.-C. Teo, S.-
H. Tay, B. Y.-H. Tan, K.-H. Lim, Tetrahedron Lett., 2011, 52
1161; (c) S. Liu, J. Zhou, New J. Chem., 2013, 37, 2537; (d)
Y. Wang, Z. Wu, L. Wang, Z. Li, X. Zhou, Chem. Eur. J.,
2009, 15, 8971; (e) J. Peng, M. Ye, C. Zong, F. Hu, L. Feng,
,
X. Wang, Y. Wang, C. Chen, J. Org. Chem., 2011, 76, 716; (f)
K. Swapna, S. N. Murthy, Y. V. D. Nageswar, Eur. J. Org.
Chem., 2010, 6678; (g) X. Li, D. Yang, Y. Jiang, H. Fu,
Green Chem., 2010, 12, 1097; (h) Z.-J. Liu, J.-P. Vors, E. R.
F. Gesing, C. Bolm, Green Chem., 2011, 13, 42; (i) L. Liang,
Z. Li, X. Zhou, Org. Lett., 2009, 11, 3294; (j) J. Engel-
Andreasen, B. Shimpukade, T. Ulven, Green Chem., 2013, 15
336; (k) X. Zhu, L. Su, L. Huang, G. Chen, J. Wang, H. Song,
Y. Wan, Eur. J. Org. Chem., 2009, 635; (l) S. Rçttger, P. J. R.
,
Sjçberg, M. Larhed, J. Comb. Chem., 2007, 9, 204; (m) J.
Jiao, X.-R. Zhang, N.-H. Chang, J. Wang, J.-F. Wei, X.-Y.
Shi, Z.-G. Chen, J. Org. Chem., 2011, 76, 1180; (n) M.
Huang, X. Lin, X. Zhu, W. Peng, J. Xie, Y. Wan, Eur. J. Org.
Chem., 2011, 4523; (o) Z. Quan, H. Xia, Z. Zhang, Y. Da, X.
Wang, Chin. J. Chem., 2013, 31, 501; (p) K. K. Sharma, M.
Mandloi, N. Raia, R. Jain, RSC Adv., 2016,
6, 96762.
10 M. Bollenbach, P. Wagner, P. G. V. Aquino, J. Bourguignon,
F. Bihel, C. Salomé, M. Schmitt, Chemsuschem, 2016,
9,
3244.
11 (a) D. Wang, D. Kuang, F. Zhang, C. Yang, X. Zhu, Adv.
Synth. Catal., 2015, 357, 714; (b) D. Wang, D. Kuang, F.
Zhang, Y. Liu, S. Ning, Tetrahedron Lett., 2014, 55, 7121; (c)
D. Wang, D. Kuang, F. Zhang, S. Tang, W. Jiang, Eur. J. Org.
Chem., 2014, 315; (d) D. Wang, F. Zhang, D. Kuang, J. Yu, J.
Li, Green Chem., 2012, 14, 1268.
4 | J. Name., 2012, 00, 1-3
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