An efficient, eco-friendly and sustainable tandem oxidative amidation of alcohols with amines catalyzed by heteropolyanion-based ionic liquids via a bifunctional catalysis process

Article abstract of DOI:10.1016/j.tet.2016.11.002

An efficient, eco-friendly and sustainable method for the tandem oxidative amidation of alcohols with amines has been reported. Using heteropolyanion-based ionic liquids as the catalyst and tert-butyl hydroperoxide as the oxidant, this amidation reaction is operationally straightforward and provides a series of primary, secondary and tertiary amides derivatives in moderate to good yields. Solvent-free media, microwave-promoted conditions and reusability of catalysts are the main highlights. Further, the proposed bifunctional catalysis mechanistic pathway has been briefly investigated in this report.

Full text of DOI:10.1016/j.tet.2016.11.002

Accepted Manuscript
An efficient, eco-friendly and sustainable tandem oxidative amidation of alcohols with
amines catalyzed by heteropolyanion-based ionic liquids via a bifunctional catalysis
process
Renzhong Fu, Yang Yang, Wei Feng, Qiuxia Ge, Yan Feng, Xiaojun Zeng, Wen Chai,
Jun Yi, Rongxin Yuan
PII:
S0040-4020(16)31134-6
10.1016/j.tet.2016.11.002
TET 28216
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 9 September 2016
Revised Date: 26 October 2016
Accepted Date: 1 November 2016
Please cite this article as: Fu R, Yang Y, Feng W, Ge Q, Feng Y, Zeng X, Chai W, Yi J, Yuan R, An
efficient, eco-friendly and sustainable tandem oxidative amidation of alcohols with amines catalyzed
by heteropolyanion-based ionic liquids via a bifunctional catalysis process, Tetrahedron (2016), doi:
10.1016/j.tet.2016.11.002.
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Renzhong Fu, Yang Yang*, Wei Feng, Qiuxia Ge, Yan Feng, Xiaojun Zeng, Wen Chai, Jun Yi*, Rongxin Yuan
Jiangsu Laboratory of Advanced Functional Material, School of Chemistry and Materials Engineering,
Changshu Institute of Technology, Changshu 215500, P.R. China

1
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Tetrahedron
journal homepage: www.elsevier.com
An efficient, eco-friendly and sustainable tandem oxidative amidation of alcohols
with amines catalyzed by heteropolyanion-based ionic liquids via a bifunctional
catalysis process
Renzhong Fu, Yang Yang*, Wei Feng, Qiuxia Ge, Yan Feng, Xiaojun Zeng, Wen Chai, Jun Yi*, Rongxin
Yuan
Jiangsu Laboratory of Advanced Functional Material, School of Chemistry and Materials Engineering, Changshu Institute of Technology, Changshu 215500,
P.R. China
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
An efficient, eco-friendly and sustainable method for the tandem oxidative amidation of alcohols
with amines has been reported. Using heteropolyanion-based ionic liquids as the catalyst and
tert-butyl hydroperoxide as the oxidant, this amidation reaction is operationally straightforward
and provides a series of primary, secondary and tertiary amides derivatives in moderate to good
yields. Solvent-free media, microwave-promoted conditions and reusability of catalysts are the
main highlights. Further, the proposed bifunctional catalysis mechanistic pathway has been
briefly investigated in this report.
Available online
Keywords:
Amide
Ionic liquid
2
009 Elsevier Ltd. All rights reserved.
Microwave-assisted
Oxidative amidation
Solvent-free condition
31
32-35
36-38
1
. Introduction
catalyst systems have been reported, such as, Zn, Fe,
Au
39-40
Cu . However, these methodologies suffer from some
common demerits that greatly restricted large scale industrial
applications, such as requirement for toxic or expensive metal
reagents and oxidants, pre-treatment step to convert amines into
their salts, narrow substrate scope and difficulties in separation
and recycling of the catalysts. Just recently, several reports
afforded attractive approachs for the tandem oxidative amidation
chemistry from the view point of green chemistry introducing
Amide bond formation is one of the key reactions in modern
chemistry, material science, pharmaceutical industry and
1-5
biology.
Amides represent a wide range of remarkable
pharmacological and agrochemical activities as well as versatile
building blocks for the synthesis of various useful molecules,
therefore amidation reaction was regard as a high priority
6-10
research field.
Generally, traditional amide formation involves the reaction
of amines with activated carboxylic acid derivatives or coupling
41
42-46
cascade strategy, metal-free catalysis
and catalyst-free
47
reaction, but with limited substrate scope. Therefore, there is an
urgent need to develop more efficient and sustainable catalytic
processes for tandem oxidative amidation of alcohols.
11-13
with carboxylic acids mediated by a coupling reagent,
which
are limited in industrial application by poor atom-efficiency,
harsh reaction conditions, toxicity issues and excess amount of
In the last few decades, environmentally benign and
sustainable development has been accepted as a common
1
4-15
wastes.
Several alternative methods, such as the Beckmann
1
6
1
7
rearrangement,
the Staudinger reaction,
the Schmidt
48
knowledge by chemical industry. From the view point of
18
19
reaction, hydroamidation of alkynes, iodonium-promoted
nitroalkane amine coupling reaction and transamidation of
primary amides, have emerged to improve the preparation of
amides. Considering the cheapness, stability and easy
availability of alcohols, chemists are now focusing on the direct
organic synthesis, the use of more eco-benign catalysts and their
20
49-50
simple recovery are the main targets.
So far, ionic liquids
21
(
ILs) as efficient and eco-friendly solvents and/or catalysts in
organic reactions provide both economical and ecological
51-52
benefits.
Recently, a series of heteropolyanion-based ILs
22-47
conversion of alcohols and amines into amides,
which is
(HPAILs) have emerged as new species of hybrid materials,
quite attractive in terms of atom economical and environmentally
benign considerations. Since 2007, Milstein et al. and other
groups have reported the transition metal-catalyzed
which were prepared by combining Keggin heteropolyanions
with ‘task-specific’ IL (TSIL) cations containing special
53-55
functional groups.
In addition, protocols containing HPAILs
22-30
dehydrogenative amidation of alcohols.
Recently, the tandem
56-61
are an attractive alternative for traditional acid-catalyzed
or
oxidative amidation of alcohols with amine as another alternative
approach has received sustained attention. To date, several metal

2
Tetrahedron
ir MA
62-68
oxidative
organic transformations be
A
ca
C
us
C
e
E
o
P
f
T
t
E
he
D
o
N
rde
U
r
S
to
C
im
R
p
I
rove the yield, some adjustments to the reaction
P
T
operational simplicity, no toxicity, easy isolation and reusability.
During the last years a large number of publications have
shown that microwave(MW)-assisted chemical processing
generally leads to the significant rate enhancements, yield and
selectivity improvements as well as less environmental pollution
matching with the goal of green chemistry.
group has reported HPAILs as eco-benign and highly efficient
catalysts for amidation of carboxylic acid derivatives (Scheme
conditions were made. It was shown that the yield of the reaction
apparently increased when the reaction mixture was
o
conventionally heated at 90 C (Table 1, entry 3, 73% yield), but
higher temperature (100 C) was not beneficial to the product
o
(Table 1, entry 4, 70% yield). We reasoned that the lower yield
at higher temperatures could be due to the partial over oxidation
of benzyl alcohol to benzoic acid as a side product. To our
delight, when MW-assisted heating was introduced, more
efficient result was observed (Table 1, entry 3 and 4). Then,
other common oxidants including H O , Oxone, NaOCl, m-
69-70
Recently, our
71-73
74
1
(a))
and oxidative amidation of aldehydes (Scheme 1(b))
with amines. As a part of our research to pursue novel, efficient
and green methods for organic transformations,
wish to report the MW-assisted HPAILs catalyzed tandem
oxidative amidation of alcohols with amines via a bifunctional
catalysis process (Scheme 1(c)).
2
2
71-78
herein we
CPBA were screened, but in all cases only 0–5% amide product
formation was observed (Table 1, entries 5–8). When anhydrous
TBHP (5.5 M in decane) was used as the oxidant, a obvious
decreased yield proved that using of aqueous medium could
boost the oxidative amidation (Table 1, entry 9). Subsequently,
the equiv. number of TBHP were also investigated (Table 1,
entries 2, 10–11), which showed that 3.0 equiv was suitable for
the best reaction conditions. Moreover other experiments were
carried out to investigate the effect of the HPAILs on the
reaction. To our surprise, decreasing the catalyst loading to 1
mol% led to the formation of the amide product in little lower
yield, while much more amount (3 mol%) was not beneficial to
Table 1. Optimization of the reaction conditions for oxidative
a
amidation of benzyl alcohol with 2-phenylethylamine.
O
H
catalyst
( )2
OH
N
N
(
)2
oxidant
conditions
H
H
Scheme 1. HPAIL catalyzed amidation reactions developed
1a
2a
3a
by our group.
Entry
Catalyst [mol %]
–
Oxidant
Time
Yield
(%)
b
(h)
2
. Results and discussions
c
1
2
TBHP
TBHP
TBHP
TBHP
12
26
Based on our previous investigations in HPAILs catalyzed
organic reactions,
triethylamine based HPAILs were chosen as potential catalysts
for this tandem oxidative amidation (Figure 1).
c
7
1-75
[PyPS]
3
3
3
3
3
3
PW12
O
40 [2]
12
61
N-substituted imidazole, pyridine and
d
3
[PyPS]
[PyPS]
[PyPS]
[PyPS]
[PyPS]
PW12
O
40 [2]
40 [2]
40 [2]
40 [2]
40 [2]
12, 1
73 , 86
e
4
PW12
PW12
PW12
PW12
O
12, 1
1
70 , 75
X = PW12O40
,
5
O
O
O
H
2
O
2
<5
<5
<5
<5
1
-Methyl-3-(3-sulfopropyl)imidazolium
SO H
[MIMPS] PW12O40
);
6
Oxone
m-CPBA
NaOCl
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
TBHP
1
3
3- phosphotungstate (
X = PMo12O40,
1
3
X
N
N
3
7
1
-Methyl-3-(3-sulfopropyl)imidazolium
phosphomolybdate ([MIMPS] PMo12O40
)
8
[PyPS] PW O [2]
1
3
3
3
3
3
3
3
12 40
X = PW12O40
-(3-Sulfopropyl)pyridinium
phosphotungstate ([PyPS] PW12O40);
,
f
9
[PyPS]
[PyPS]
[PyPS]
[PyPS]
[PyPS]
PW12
O
O
O
O
O
40 [2]
1
21
1
X3-
g
3
10
11
PW12
PW12
PW12
PW12
40 [2]
40 [2]
40 [1]
40 [3]
1
65
81
N
SO H 3
3
X = PMo12O40
-(3-Sulfopropyl)pyridinium
phosphomolybdate ([PyPS] PMo12O40
,
h
1
1
)
3
1
2
1
80
85
75
79
66
65
54
X = PW12O40
Triethyl-(3-sulfopropyl)aminium
[TEAPS] PW
,
13
14
1
C H
N
2
5
C H
X3- phosphotungstate (
O
40);
2
5
5
3
12
SO H
3
[PyPS] PMo O [2]
1
3
X = PMo12O40,
Triethyl-(3-sulfopropyl)aminium
phosphomolybdate ([TEAPS] PMo12O40
3
12 40
C H
2
1
1
5
6
[MIMPS]
3
PW12
O40 [2]
1
)
3
[MIMPS]
3
PMo12
O40 [2]
1
Figure 1. N-substituted imidazole, pyrdine and triethylamine based HPAILs.
Our initial studies focused on the reaction of commercially
available benzyl alcohol (1a) with 2-phenylethylamine (2a) as
the model substrates to optimize the reaction conditions (Table
17
[TEAPS] PW O [2]
3
12 40
1
1
8
[TEAPS]
3
PMo12
O40 [2]
1
a
1
). Firstly, as
a
control experiment, aqueous tert-butyl
Reaction conditions: benzyl alcohol 1a (2 mmol), 2-phenylethylamine 2a
(2.4 mmol), HPAIL catalyst and TBHP (3 equiv., 70% aqueous solution)
hydroperoxide (TBHP) was used as the oxidant in the absence of
o
under MW (700 W) and solvent-free condition at 90 C in a sealed glass
pressure tube.
Isolated yields based on benzyl alcohol 1a.
Reaction was conducted under conventional heating at 70 C.
Reaction was conducted under conventional heating at 90 C.
Reaction was conducted under conventional heating at 100 C.
TBHP (3 equiv., 5.5 M in decane) was used.
TBHP (2.5 equiv., 70% aqueous solution) was used.
TBHP (4 equiv., 70% aqueous solution) was used.
any catalyst and additional solvent under conventional heating at
o
7
0
C. After
a
prolonged reaction time of 12
h
N-
b
c
d
e
f
o
phenethylbenzamide was achieved in only 26% yield (Table 1,
entry 1), whereas addition of 2 mol% amount of [PyPS] PW O
to the reaction mixture resulted in the desired amide in 61%
yield (Table 1, entry 2). The results revealed that this tandem
oxidative amidation of alcohol could be promoted by HPAILs. In
o
3
12 40
o
g
h

3
the product (Table 1, entries 12–13). In the c
A
as
C
es
C
of
E
r
P
ea
T
ct
E
io
D
ns MA
T
N
ab
U
le
S
2
C
. H
R
PAIPIL
T
catalyzed tandem oxidative amidation of
a
using related HPAILs, [PyPS] PW O was found to be more
alcohols with amines.
3
12 40
efficient than other species (Table 1, entries 14–18). Finally,
optimum result was obtained when the reaction was performed
using 2 mol% of [PyPS] PW O under MW and solvent-free
3
12 40
o
condition at 90 C affording N-phenethylbenzamide in 86% yield
(
Table 1, entry 3).
With the optimized conditions in hand, the substrate scope and
b
limitations could now be more thoroughly explored. A broad
range of primary, secondary and tertiary amides were
successfully prepared in moderate to good yields. Firstly, the
comparative results under MW-assisted and conventional heating
conditions further approved that MW could result in not only
rate enhancements but also yield improvements in this reaction
Product: yield (%)
c
c
c
c
3a: 86 (73)
3b: 84 (70)
3c: 79 (62)
3d: 88 (63)
d
d
(84)
(80)
(
Table 2, 3a-3e). In addition, the reaction was compatible with
various aromatic alcohols bearing substituents, such as OMe, Me,
F, Cl, Br, NO , CO Me, CN and CF which are post-
diversification in pharmaceutical chemistry. Generally speaking,
in the case of electron-donating groups such as OMe and Me
2
2
3
c
e
3
e: 71 (55)
3f: 90
3g: -
3h: 84
O
N
Ph
N
N
(
Table 2, 4a and 5a), on the benzyl alcohol, the yield was lower
H
than the electron with-drawing groups, such as F, Cl, Br, NO2,
3i: 83
3j: 78
3k: 77
3o: 45
3l: 71
CO Me, CN and CF (Table 2, 6a-13a). The phenomenon can be
2
3
explained that, oxidation of the aromatic alcohols to acids were
faster than amide formation with electron-donating groups.
Moreover, heteroaromatic alcohols, such as pyridin-2-
ylmethanol, pyridin-3-ylmethanol and thiophen-2-ylmethanol,
were also efficiently transformed, affording the corresponding
amides in good yields (Table 2, 14a-16a). It was worth
mentioning that aliphatic alcohols, which have proven
challenging for other oxidative amidation reactions, also afford
the desired amides in moderate yields (Table 2, 17a-18a). In
order to further illustrate the potential utility, gram-scale
experiments were conducted, whereupon the products were
obtained with almost no change in yields (Table 2, 3a-3b).
4
8
a: 69
a: 85
3
5
m: 73
a: 73
3n: 75
6a: 80
7a: 84
O
O
N
N
H
H
O2N
O2N
9a: 83
9d: -
9
b: 88
9c: 80
11a: 87
1
2a: 82
9
1
e: 92
With regard to the reactivities of amines, the results showed
that all the linear alkylamines and ammonia can be converted
into the corresponding amides in an efficient manner (Table 2,
10a: 53
3
a-3d, 4a-9b, 10a-18a). However, the bulkier primary amines
3a: 80
1
4a: 79
15a: 81
17b: 68
15b: 84
18a: 65
gave low yields (Table 2, 3e, 9c-9d). The results revealed that
the reaction is sensitive to steric hindrance of amies. Delightfully,
secondary amine carried out this reaction and the corresponding
tertiary amides obtained in good yields (Table 2, 3f, 9e). To
further establish the general utility, aromatic amines were test as
substrates. It was shown that when aniline was employed the
imine was the only main product (Table 2, 3g), but the
methodology worked well with heteroaryl amine, such as,
1
6a: 76
17a: 61
a
Reaction condition : alcohol 1 (2 mmol), amine 2 (2.4 mmol),
PyPS] 40 (2 mol %) and TBHP (3.0 equiv., 70% aqueous solution)
under MW (700 W) and solvent-free condition at 90 C in a sealed glass
pressure tube for 1h.
Isolated yields based on alcohol.
Isolated yields under conventional heating at 90 C for 12h.
[
3
PW12O
o
b
c
d
e
o
aminopyridine,
aminopyrazine,
aminopyrimidine
and
Isolated yields from the 20 mmol scale experiment under MW condition.
The imine is the main product.
aminobenzothiazole (Table 2, 3h-3n, 17b, 18a). Moreover,
secondary amino pyridine (N-heptyl-2-aminopyridine) showed
low reactivities in this catalyzed oxidative amidation (Table 2,
3
o).
In the view of sustainable chemistry, the recyclability and
reusability of HPAILs were investigated with the reaction of
benzyl alcohol and 2-phenylethylamine under the optimized
reaction conditions. After completion of the reaction in the first
run, the aqueous reaction mixture was concentrated under
reduced pressure and the EtOAc was added. After
vigorousstirring the catalyst can be easily retrieved from the
reaction mixture by simple centrifugation or filtration, washed
with ethyl acetate to remove traces of the previous reaction
mixture and drying. The catalyst recycled up to six times in this
tandem oxidation amidation reaction with a little loss of catalytic
efficiency (Figure 2). Furthermore, the recycled HPAILs were
characterized and the results indicated the maintaining of the
original structure (detailed spectra in Supplementary Material).
Figure 2. Reusability studies of the catalyst for the catalyzed tandem
oxidative amidation.

4
Tetrahedron
Thus, the robustness of the catalyst and it
demonstrated.
A
s r
C
eu
C
sa
E
bi
P
lit
T
y
E
was MAin
D
NU
term
S
ed
C
iat
R
e
I
w
P
as formed with regenerated HPAIL cation catalyst.
T
The reaction medium with the presence of water could reduce
the imine formation from the hemiaminal intermediate. Finally,
the amide product was obtained via hydroxyl oxidation by
peroxo-W species including peroxo-W ring opening,
protonexchange, subsequent dehydration and desorption. The
present bifunctional catalysis process appears to be simpler,
much more efficient and cost-effective when compared with the
currently available catalytic systems.
To gain insight into the mechanism of the reaction, some
control experiments were set up. According to the best accepted
mechanism,
then underwent oxidative amidation with the possible
intermediates including imine, carboxylic acid or hemiaminal.
Since the unstable hemiaminal could not be separated and
purified, both of the possible intermediate imine (Scheme 2, Eq.
31-47
the alcohol was easily oxidized to aldehyde and
1
) and carboxylic acid (Scheme 2, Eq. 2) were used as substrate,
3
. Conclusion
and the low yields indicated that this oxidative amination of
aldehydes most likely proceeds through hemiaminal intermediate
formation. Besides, when PyPSCl (Scheme 2, Eq. 3) or pure
H PW O (Scheme 2, Eq. 4) were used as catalysts at standard
In conclusion, we have developed a HPAILs promoted
efficient and sustainable tandem oxidative amidation of alcohols
with amine under MW-assisted and solvent-free conditions. This
methodology presents a practical protocol for the synthesis of
amides, including primary, secondary and tertiary alkyl/aryl
amides. Compared to previously known reports, operational
simplicity, solvent-free media, reusable catalysts, environmental
friendliness and reduced generation of hazardous waste are the
advantages of this procedure. The bifunctional catalysis
mechanism of HPAILs in this reaction was briefly investigated.
The expansion of this chemistry to other organic transformations
is ongoing in our laboratory.
3
12 40
condition, the relative low yields implied the cooperation of
PyPS cation and PW O anion in the catalytic cycle. Based on
12
40
the previous reports, the peroxo-W species derived from W
species in heteropolyanion with oxidants are well accepted as the
79-80
catalytically active sites for versatile organic oxidations.
Thus, in terms of previous experimental results and our reports
71-75
on HPAILs catalyzed reactions,
a bifunctional catalysis
mechanistic pathway is proposed for understanding the catalytic
performance of HPAILs in Figure 3.
4
. Experimental section
4
.1. General methods
Reagent grade solvents were used for extraction,
recrystallization and flash chromatography. All other
commercial reagents were used as received without additional
purification. The progress of reactions were checked by
analytical thin-layer chromatography (TLC, silica gel 60 F-254
plates). The plates were visualized first with UV illumination
followed by iodine or phosphomolybdic acid hydrate. Column
chromatography was performed using silica gel (200-300 mesh).
NMR spectra were obtained using BRUKER AVANCE III
1
instrument. H NMR spectra were recorded at 300 MHz or 400
Scheme 2. Control experiments for the mechanism study.
MHz and are reported in parts per million (ppm) on the δ scale
relative to tetramethylsilane (TMS) as an internal standard.
NMR spectra were recorded at 75 MHz or 100 MHz and are
reported in parts per million (ppm) on the δ scale relative to
CDCl (δ 77.16) and DMSO-d (δ 39.52). Multiplicities are
indicated as the following : s, singlet; d, doublet; t, triplet; q,
quartet; m, multiplet; dd, doubled doublet; td, tripled doublet; br,
broad. Coupling constants (J values) where noted are quoted in
hertz. Mass spectra were obtained using Agilent 1260-6120
(ESI) instrument. MW-promoted heating was obtained using
MAS-II instrument manufactured by Shanghai Sineo Microwave
Chemistry Technology Co., Ltd. The melting point was
uncorrected.
1
3
O
H
H
C
O
O
H
O
H
-
O
+
W
H
N - O2S O
W
O
H
H
3
+
-
O
R1
R1
O +
H
H
R1
H
N R3
R2
R1
H-O-H
H
R1
3
6
OH
H
H
O
O
O
R2
N
R3
t-BuOH
t-BuOH
W
W
O2
S
N
OH
3
O
O O
t-BuOOH
t-BuOOH
O2S OH 3
N
O
W
W
OH
H
R3
R3
R1
H
N
O
H
R1
N
R2
R1
N R3
R
2
R
hemiaminal
intermediate
2
O
H
H-O-H
O
H
R3
N
O
O H
H
R3 H2O -H2O
3
O
= PW12O403-
W
O
W
O
N
R
R2
R2
W
4.2. Typical Procedure for the Synthesis of HPAILs
R1
R1
N
R1
R2
imine
To a well-stirred mixture of 12.2 g 1,3-propane sulfone (0.10
mol) in 30 mL toluene were added 8.9 mL pyridine (0.11 mol).
The reaction mixture was stirred for 24 h at 50 C under a
nitrogen atmosphere resulting a white precipitate (PyPS). After
the completion of reaction, it was cooled to room temperature.
PyPS was obtained after filtration, washing with diethyl ether
and drying in a vacuum. And then 18.1 g PyPS (0.09 mol) was
added to an aqueous solution of 86.4 g H PW O (0.03 mol).
After stirring at room temperature for 24 h, the solution was
removed in vacuum to give the HPAIL product [PyPS] PW O
solid. Thus [PyPS] PMo O , [MIMPS] PW O ,
MIMPS] PMo O , [TEAPS] PW O and [TEAPS] PMo O
Figure 3. Plausible bifunctional catalysis mechanistic pathway to amides.
o
The bifunctional catalysis mechanism of HPAILs involved
cooperative activations of hydroxyl oxidation and the addition
of the amine to the carbonyl. Firstly, in the presence of TBHP as
the oxidant, the peroxo-W complex was generated from W
species in the HPAILs anion framework that supposed to be the
active site which makes the alcohol oxidation to aldehyde.
Secondly, carbonyl activation of aldehyde by the coordination
with aminium cation as well as N-H activation of amine by the
coordination with sulfonic group in HPAIL cation were achieve.
After an addition of the amine to the carbonyl carbon atom,
proton-exchange and subsequent desorption, hemiaminal
3
12 40
3
12 40
as
[
a
3
12 40
3
12 40
12 40
3
12 40
3
12 40
3
were prepared using according starting materials.

5
4
.2.1. 1-(3-Sulfopropyl)pyridine (PyPS).
White solid. Mp: 62.5-64.8 °C; IR (KBr) : 3443, 3159, 3103,
572, 1459, 1184, 1010, 842, 780, 654, 601, 528 cm ; H NMR
White solid. Mp: 185.5-187.8 °C; IR (KBr) : 3440, 1485,
ACCEPTED MANUSCRIPT
-1 1
1460, 1400, 1230, 1170, 1080, 978, 893, 810 cm ; H NMR (400
MHz, D O) δ 3.29-3.28 (m, 8H), 2.98-2.93 (m, 2H), 2.17-2.01
-
1 1
1
2
13
(400 MHz, D O) δ 8.86 (d, J = 6.0 Hz, 2H), 8.53 (t, J = 7.8 Hz,
(m, 2H), 1.28-1.25 (m, 9H); C NMR (100 MHz, D
O) δ 60.2,
2
+
2
1
7
1
H), 8.06 (t, J = 7.6 Hz, 2H), 4.75 (t, J = 7.2 Hz, 2H), 2.95 (t, J =
52.9, 48.0, 24.3, 6.7; HRMS Calcd for C S (M + H ):
H22NO
9 3
13
2
24.1315; Found: 224.1318.
.2 Hz, 2H), 2.47-2.40 (m, 2H); C NMR (100 MHz, D O) δ
2
46.0, 144.5, 128.5, 60.0, 47.1, 26.2; HRMS Calcd for
4
.2.9. Triethyl-(3-sulfopropyl)aminium
+
C H NO S (M + H ): 202.0532; Found: 202.0534.
8
12
3
hosphomolybdate ([TEAPS] PMo O4 0
)
3
1 2
1
4
.2.2. 1-Methyl-3-(3-sulfopropyl)imidazole
Green solid. Mp: 165.5-167.8 °C; H NMR (400 MHz, D
O) δ
2
(
MIMPS)
3.37-3.21 (m, 8H), 2.97-2.87 (m, 2H), 2.16-2.06 (m, 2H), 1.28-
13
White solid. Mp: 55.5-58.8 °C; IR (KBr) : 3433, 3025, 2944,
631, 1487, 1328, 1197, 1099, 775, 687, 604, 522, 481 cm ; H
1.25 (m, 9H); C NMR (100 MHz, D
O) δ 60.2, 52.9, 48.0, 24.3,
2
+
-
1
1
1
6.7; HRMS Calcd for C S (M + H ): 224.1315; Found:
H22NO
9 3
2
24.1318.
NMR (400 MHz, D O) δ 8.71 (s, 1H), 7.48 (s, 1H), 7.41 (s, 1H),
2
4
2
1
.32 (t, J = 7.2 Hz, 2H), 3.86 (s, 3H), 2.88 (t, J = 7.2 Hz, 2H),
4
.3. Typical Procedure for the Synthesis of Amides by HPAILs
13
.31-2.24 (m, 2H); C NMR (100 MHz, D O) δ 136.2, 123.8,
2
catalyzed tandem oxidative amidation
22.2, 47.8, 47.3, 35.8, 25.1; HRMS Calcd for C H N O S (M +
7
13
2
3
+
H ): 205.0641; Found: 205.0645.
[PyPS] PW O (0.14 g, 0.04 mmol) and TBHP (0.78 g, 3.0
3
12 40
equiv., 70% aqueous solution) were added to a mixture of
alcohol (2 mmol) and amine (2.4 mmol) in a 15 mL a glass
pressure tube. After the pressure tube was closed, the reaction
4
.2.3. Triethyl-(3-sulfopropyl)amine (TEAPS)
White solid. Mp: 48.5-49.8 °C; H NMR (400 MHz, D O) δ
1
2
3
2
4
2
.27 (q, J = 7.2 Hz, 8H), 2.93 (t, J = 7.2 Hz, 2H), 2.10-2.06 (m,
o
mixture was stirred at 90 C under MW (700 W). The progress of
13
H), 1.27-1.20 (m, 9H); C NMR (100 MHz, D O) δ 52.7, 47.3,
2
the reaction was monitored by TLC. After the reaction is
completed, the aqueous reaction mixture was concentrated under
reduced pressure, the remaining mixture was diluted with ethyl
acetate (20 mL) with stirring for 30 min. The insoluble catalyst
was recovered by filtration or centrifugation. The filtrate was
evaporated and the residue was directly purified by
recrystallization or column chromatography to give amide
product.
+
6.7, 17.3, 8.3; HRMS Calcd for C H NO S (M + H ):
9
22
3
24.1315; Found: 224.1318.
4
.2.4. 1-(3-Sulfopropyl)pyridinium
phosphotungstate ([PyPS] PW O4 0
)
3
1 2
White solid. Mp: 142.5-145.8 °C; IR (KBr) : 3409, 3131,
068, 1633, 1488, 1220, 1182, 1079, 1042, 978, 896, 805, 681,
3
5
-
1 1
95, 521 cm ; H NMR (400 MHz, D O) δ 8.87 (brs, 2H), 8.59
2
(
brs, 1H), 8.11 (brs, 2H), 4.78 (brs, 2H), 2.97 (brs, 2H), 2.46 (brs,
4
.3.1. N-Phenethylbenzamide (3a)
13
2
2
2
H); C NMR (100 MHz, D O) δ 146.3, 144.4, 128.6, 60.2, 47.2,
1
2
Yellow solid. Mp: 115.1-117.7 °C; H NMR (400 MHz,
CDCl ) δ 7.69 (d, J = 7.6 Hz, 2H), 7.47 (t, J = 7.6 Hz, 1H), 7.39
+
6.2; HRMS Calcd for C H NO S (M + H ): 202.0532; Found:
8
12
3
3
02.0535.
(t, J = 7.6 Hz, 2H), 7.32 (t, J = 7.6 Hz, 2H), 7.25-7.22 (m, 3H),
4
.2.5. 1-(3-Sulfopropyl)pyridinium
6.27 (brs, 1H), 3.71 (q, J = 6.8 Hz, 2H), 2.93 (t, J = 6.8 Hz, 2H);
13
hosphomolybdate ([PyPS] PMo O4 0
)
C NMR (100 MHz, CDCl
) δ 167.6, 139.0, 134.8, 131.5, 128.9,
3
3
1 2
1
28.8, 128.7, 126.9, 126.7, 41.3, 35.8; HRMS Calcd for
Green solid. Mp: 142.5-145.8 °C; IR (KBr) : 3421, 3066,
633, 1488, 1181, 1062, 1044, 957, 880, 795, 680, 609, 505 cm ;
+
-
1
C H NO (M + H ): 226.1226; Found: 226.1224.
1
15 16
1
H NMR (400 MHz, D O) δ 8.87 (brs, 2H), 8.67 (t, J = 7.2 Hz,
2
4
.3.2. N-Benzylbenzamide (3b)
Yellow solid. Mp: 120.2-122.5 °C; H NMR (400 MHz,
1
7
1
H), 8.20 (t, J = 7.2 Hz, 2H), 4.82 (t, J = 7.2 Hz, 2H), 2.98 (t, J =
1
13
.2 Hz, 2H), 2.51-2.43 (m, 2H); C NMR (100 MHz, D O) δ
2
CDCl ) δ 7.80-7.78 (m, 2H), 7.52-7.48 (m, 1H), 7.44-7.40 (m,
3
46.4, 144.3, 129.0, 60.3, 47.3, 26.5; HRMS Calcd for
+
2H), 7.36-7.28 (m, 5H), 6.48 (brs, 1H), 4.64 (d, J = 5.6 Hz, 2H);
C H NO S (M + H ): 202.0532; Found: 202.0536.
13
8
12
3
C NMR (100 MHz, CDCl ) δ 167.5, 138.3, 134.5, 131.7, 128.9,
3
4
.2.6. 1-Methyl-3-(3-sulfopropyl)imidazolium
128.7, 128.0, 127.7, 127.1, 44.2; HRMS Calcd for C14
+ H ): 212.1070; Found: 212.1074.
H14NO (M
+
phosphotungstate ([MIMPS] PW O4 0
)
3
1 2
White solid. Mp: 119.5-120.8 °C; IR (KBr) : 3417, 3147,
636, 1571, 1459, 1418, 1173, 1080, 980, 897, 800, 516 cm ; H
4
.3.3. N-octylbenzamide (3c)
Yellow solid. Mp: 85.2-86.5 °C; H NMR (400 MHz, CDCl )
-
1 1
1
1
3
NMR (400 MHz, D O) δ 8.68 (s, 1H), 7.55 (s, 1H), 7.51 (s, 1H),
2
δ 7.77-7.75 (m, 2H), 7.50-7.46 (m, 1H), 7.44-7.40 (m, 2H), 6.25
(brs, 1H), 3.45 (q, J = 6.8 Hz, 2H), 4.61 (d, J = 5.6 Hz, 2H),
4
2
1
.42 (t, J = 7.2 Hz, 2H), 4.02 (s, 3H), 2.91 (t, J = 7.2 Hz, 2H),
13
.36-2.28 (m, 2H); C NMR (100 MHz, D O) δ 135.9, 124.2,
2
1
.65-1.57 (m, 2H), 1.39-1.27 (m, 10H), 0.88 (t, J = 6.8 Hz, 3H);
22.6, 48.1, 47.4, 36.1, 25.3; HRMS Calcd for C H N O S (M +
13
7
13
2
3
+
C NMR (100 MHz, CDCl
) δ 167.7, 134.9, 131.4, 128.6, 127.0,
3
H ): 205.0641; Found: 205.0645.
4
C
0.3, 31.9, 29.8, 29.4, 29.3, 27.1, 22.8, 14.2; HRMS Calcd for
+
4
.2.7. 1-Methyl-3-(3-sulfopropyl)imidazolium
15
H
24NO (M + H ): 234.1852; Found: 234.1854.
.3.4. Benzamide (3d)
White solid. Mp: 134.2-136.5 °C; H NMR (400 MHz,
hosphomolybdate ([MIMPS] PMo O4 0
)
3
1 2
4
Green solid. Mp: 105.5-108.8 °C; IR (KBr) : 3422, 3149,
100, 1630, 1569, 1454, 1405, 1217, 1171, 1059, 963, 882, 796,
1
3
6
1
2
4
2
-
1
1
DMSO-d
1
DMSO-d
C
6
) δ 8.00 (brs, 1H), 7.92-7.89 (m, 2H), 7.55-7.52 (m,
10, 504 cm ; H NMR (400 MHz, D O) δ 8.63 (s, 1H), 7.48 (s,
13
2
H), 7.48-7.44 (m, 2H), 7.40 (brs, 1H); C NMR (100 MHz,
H), 7.42 (s, 1H), 4.35 (brs, 2H), 3.92 (s, 3H), 2.86 (brs, 2H),
1
3
6
) δ 168.0, 134.3, 131.2, 128.2, 127.5; HRMS Calcd for
NO (M + H ): 122.0600; Found: 122.0602.
.26 (brs, 2H); C NMR (100 MHz, D O) δ 136.3, 124.3, 122.6,
+
2
+
7
H
8
8.2, 47.4, 36.1, 25.3; HRMS Calcd for C H N O S (M + H ):
7
13
2
3
05.0641; Found: 205.0643.
4.3.5. N-(1-Phenylethyl)benzamide (3e)
1
Yellow solid. Mp: 137.4-138.7 °C; H NMR (400 MHz,
4
.2.8. Triethyl-(3-sulfopropyl)aminium
CDCl ) δ 7.78-7.76 (m, 2H), 7.51-7.47 (m, 1H), 7.44-7.34 (m,
6
phosphotungstate ([TEAPS] PW O4 0
)
3
3
1 2
H), 7.30-7.28 (m, 1H), 6.36 (brs, 1H), 5.38-5.31 (m, 1H), 1.61

6
Tetrahedron
8, MA
13
(
d, J = 6.8 Hz, 3H); C NMR (100 MHz,
A
C
C
DC
C
l
E
)
P
δ
T
16
E
6.
D
1
N
33.
U
2,
S
1
C
32
R
.1,IP13
T
1.7, 129.1, 128.2, 126.3, 124.2, 121.5, 120.5;
3
+
1
2
2
43.2, 134.7, 131.6, 128.8, 128.7, 127.6, 127.1, 126.4, 49.4,
1.8; HRMS Calcd for C H NO (M + H ): 226.1226; Found:
26.1224.
HRMS Calcd for C H N OS (M + H ): 255.0587; Found:
14
11
2
+
255.0589.
15
16
4
.3.14. N-heptyl-N-(pyridin-2-yl)benzamide (3o)
4
.3.6. Phenyl(piperidin-1-yl)methanone (3f)
Yellow solid. Mp: 108.3-109.5 °C; H NMR (300 MHz,
The presence of two rotamers (ratio 1:1) was observed in the
1
1
NMR spectra. White oil. H NMR (400 MHz, CDCl ) δ 8.13-
3
CDCl ) δ 7.39 (brs, 5H), 3.71 (brs, 2H), 3.34 (brs, 2H), 1.67 (brs,
8.11 (m, 4H), 7.91 (d, J = 4.4 Hz, 1H), 7.84 (d, J = 4.4 Hz, 1H),
7.52-7.35 (m, 8H), 6.62 (dd, J = 15.2, 8.8 Hz, 2H), 6.54 (t, J =
6.4 Hz, 1H), 6.46 (t, J = 6.4 Hz, 1H), 6.85-6.77 (m, 2H), 3.41-
3
13
4
1
H), 1.51 (brs, 2H); C NMR (75 MHz, CDCl ) δ 170.3, 136.5,
3
29.3, 128.4, 126.8, 48.7, 43.1, 26.5, 25.6, 24.6; HRMS Calcd
+
13
for C H NO (M + H ): 190.1226; Found: 190.1239.
3.31 (m, 2H), 1.68-1.22 (m, 20H), 0.85-0.80 (m, 6H); C NMR
12
16
(
100 MHz, CDCl ) δ 165.2, 157.4, 157.3, 142.9, 142.5, 140.3,
3
4
.3.7. N-(pyridin-2-yl)benzamide (3h)
White solid. Mp: 88.1-90.7 °C; H NMR (400 MHz, CDCl ) δ
.26 (brs, 1H), 8.42 (d, J = 8.4 Hz, 1H), 8.15 (dd, J = 7.6, 0.8 Hz,
H), 7.95-7.93 (m, 2H), 7.75 (td, J = 8.0, 1.6 Hz, 1H), 7.57-7.54
1
5
2
2
40.2, 134.3, 131.7, 129.8, 128.1, 111.5, 111.1, 108.1, 107.8,
3.5, 43.0, 42.0, 32.2, 32.1, 31.9, 29.4, 28.9, 27.4, 26.5, 22.7,
1
3
9
1
+
2.6, 14.2, 14.1; HRMS Calcd for C H N O (M + H ):
19
25
2
97.1961; Found: 297.1963.
(
m, 1H), 7.49-7.45 (m, 2H), 7.03 (ddd, J = 7.2, 5.0, 0.4 Hz, 1H);
1
3
4
.3.15. N-benzyl-4-methoxybenzamide (4a)
C NMR (100 MHz, CDCl ) δ 166.1, 151.8, 147.8, 138.6, 134.4,
3
1
1
32.3, 128.8, 127.4, 119.9, 114.5; HRMS Calcd for C H N O
White solid. Mp: 146.6-148.8 °C; H NMR (400 MHz,
12
11
2
+
(M + H ): 199.0866; Found: 199.0864.
CDCl ) δ 7.78-7.74 (m, 2H), 7.35-7.29 (m, 5H), 6.93-6.89 (m,
3
13
2
H), 6.40 (brs, 1H), 4.63 (d, J = 5.6 Hz, 2H), 3.84 (s, 3H);
C
4
.3.8. N-(3-methylpyridin-2-yl)benzamide (3i)
NMR (100 MHz, CDCl ) δ 167.1, 162.3, 138.5, 128.9, 128.8,
1
C H NO (M + H ): 242.1176; Found: 242.1179.
1
3
White oil. H NMR (400 MHz, CDCl ) δ 9.59 (brs, 1H), 8.22
3
27.9, 127.6, 126.7, 113.8, 55.5, 44.1; HRMS Calcd for
(d, J = 4.0 Hz, 1H), 8.01-7.99 (m, 2H), 7.65 (d, J = 7.6 Hz, 1H),
+
15
16
2
7
1
1
.56-7.52 (m, 1H), 7.48-7.44 (m, 2H), 7.16 (dd, J = 7.6, 5.0 Hz,
13
4
.3.16. N-octyl-4-methylbenzamide (5a)
H), 2.34 (s, 3H); C NMR (100 MHz, CDCl ) δ 171.3, 166.2,
3
1
50.0, 144.9, 140.7, 132.2, 129.9, 128.7, 128.0, 121.9, 18.6;
Yellow solid. Mp: 115.5-117.9 °C; H NMR (400 MHz,
+
HRMS Calcd for C H N O (M + H ): 213.1022; Found:
CDCl ) δ 7.66 (d, J = 8.0 Hz, 2H), 7.22 (d, J = 8.0 Hz, 2H), 6.11
13
13
2
3
2
13.1025.
(brs, 1H), 6.25 (brs, 1H), 3.44 (q, J = 6.8 Hz, 2H), 2.39 (s, 3H),
1.64-1.57 (m, 2H), 1.39-1.27 (m, 10H), 0.88 (t, J = 6.8 Hz, 3H);
4
.3.9. N-(5-chloropyridin-2-yl)benzamide (3j)
White solid. Mp: 144.1-146.5 °C; H NMR (400 MHz,
13
C NMR (100 MHz, CDCl ) δ 167.7, 141.8, 132.1, 129.3, 129.2,
1
3
1
27.0, 40.2, 31.9, 29.8, 29.4, 29.3, 27.1, 22.8, 21.5, 14.2; HRMS
CDCl ) δ 9.93 (brs, 1H), 8.50 (d, J = 8.8 Hz, 1H), 8.25 (d, J =
2
7
CDCl ) δ 166.4, 150.4, 145.6, 139.0, 133.7, 132.6, 130.2, 128.6,
1
2
+
3
Calcd for C H NO (M + H ): 248.2009; Found: 248.2007.
16
26
.0 Hz, 1H), 8.06-8.03 (m, 2H), 7.78 (dd, J = 8.8, 2.4 Hz, 1H),
13
4
.3.17. N-phenethyl-4-fluorobenzamide (6a)
.61-7.57 (m, 1H), 7.54-7.48 (m, 2H); C NMR (100 MHz,
1
Yellow solid. Mp: 134.2-136.6 °C; H NMR (400 MHz,
3
+
27.9, 116.0; HRMS Calcd for C H ClN O (M + H ):
CDCl ) δ 7.72-7.68 (m, 2H), 7.33-7.29 (m, 2H), 7.25-7.20 (m,
12
10
2
3
33.0476; Found: 233.0478.
3H), 7.07-7.03 (m, 2H), 6.35 (brs, 1H), 3.69 (q, J = 6.8 Hz, 2H),
1
3
2
1
1
+
.92 (t, J = 6.8 Hz, 2H); C NMR (100 MHz, CDCl ) δ 166.7,
3
4
.3.10. N-(pyrazin-2-yl)benzamide (3k)
66.0, 163.5, 138.9, 129.3, 129.2, 128.9, 128.8, 128.7, 126.9,
26.7, 115.7, 115.5, 41.4, 35.7; HRMS Calcd for C H FNO (M
H ): 244.1132; Found: 244.1135.
1
White solid. Mp: 161.3-163.1 °C; H NMR (400 MHz,
15
15
CDCl ) δ 9.75 (d, J = 1.2 Hz, 1H), 8.90 (brs, 1H), 8.38 (d, J =
+
3
2
1
1
.4 Hz, 1H), 8.23-8.22 (m, 1H), 7.97-7.95 (m, 2H), 7.63-7.59 (m,
13
4
.3.18. N-phenethyl-4-chlorobenzamide (7a)
Yellow solid. Mp: 114.4-117.1 °C; H NMR (400 MHz,
H), 7.54-7.50 (m, 2H); C NMR (100 MHz, CDCl ) δ 165.7,
3
1
48.4, 142.0, 140.4, 137.4, 133.4, 132.7, 129.0, 127.5; HRMS
+
Calcd for C H N O (M + H ): 200.0818; Found: 200.0819.
CDCl ) δ 7.62 (d, J = 8.8 Hz, 2H), 7.34 (d, J = 8.4 Hz, 2H), 7.30
11
10
3
3
(
d, J = 7.6 Hz, 2H), 7.22 (t, J = 7.6 Hz, 3H), 6.33 (brs, 1H), 3.68
4
.3.11. N-(pyrimidin-2-yl)benzamide (3l)
White solid. Mp: 157.3-159.1 °C; H NMR (400 MHz,
13
(q, J = 6.8 Hz, 2H), 2.91 (t, J = 6.8 Hz, 2H); C NMR (100
1
MHz, CDCl ) δ 166.6, 138.9, 137.7, 133.1, 131.5, 128.9, 128.8,
1
H ): 260.0837; Found: 260.0839.
3
DMSO-d ) δ 10.99 (brs, 1H), 8.74 (d, J = 4.8 Hz, 2H), 7.98 (d, J
=
4
1
6
28.4, 126.7, 41.3, 35.7; HRMS Calcd for C H ClNO (M +
15 15
+
7.2 Hz, 2H), 7.63-7.59 (m, 1H), 7.54-7.50 (m, 2H), 7.26 (t, J =
13
.8 Hz, 1H); C NMR (100 MHz, DMSO-d ) δ 165.5, 163.6,
6
4
.3.19. N-phenethyl-4-bromobenzamide (8a)
58.3, 134.2, 132.0, 128.3, 128.2, 117.3; HRMS Calcd for
+
1
C H N O (M + H ): 200.0818; Found: 200.0816.
Yellow solid. Mp: 132.4-133.8 °C; H NMR (400 MHz,
11
10
3
CDCl ) δ 7.61-7.47 (m, 4H), 7.35-7.31 (m, 2H), 7.27-7.22 (m,
3
4
.3.12. N-(pyrimidin-4-yl)benzamide (3m)
White solid. Mp: 157.3-159.1 °C; H NMR (400 MHz,
3
2
1
H), 6.14 (brs, 1H), 3.71 (q, J = 6.8 Hz, 2H), 2.93 (t, J = 6.8 Hz,
1
13
H); C NMR (100 MHz, CDCl ) δ 166.7, 138.9, 133.5, 131.9,
3
DMSO-d ) δ 10.59 (brs, 1H), 8.49-8.48 (m, 2H), 7.98 (d, J = 7.2
Hz, 2H), 7.80 (d, J = 5.2 Hz, 1H ), 7.65-7.63 (m, 1H), 7.58-7.54
6
28.9, 128.8, 128.6, 126.8, 126.2, 41.3, 35.7; HRMS Calcd for
+
C H BrNO (M + H ): 304.0332; Found: 304.0334.
13
15 15
(m, 2H); C NMR (100 MHz, DMSO-d ) δ 166.5, 150.3, 145.9,
6
4
.3.20. N-(furan-2-ylmethyl)-4-nitrobenzamide (9a)
Yellow solid. Mp: 135.2-136.5 °C; H NMR (400 MHz,
1
34.2, 132.1, 128.5, 127.8, 114.0; HRMS Calcd for C H N O
11 10 3
+
1
(M + H ): 200.0818; Found: 200.0816.
CDCl ) δ 8.28 (d, J = 8.8 Hz, 2H), 7.33-7.95 (d, J = 8.8 Hz, 2H),
3
4
.3.13. N-(benzo[d]thiazol-2-yl)benzamide (3n)
7
.39 (s, 1H), 6.55 (brs, 1H), 6..37-6.33 (m, 2H), 4.67 (d, J = 5.6
1
White solid. Mp: 143.3-145.1 °C; H NMR (400 MHz,
DMSO-d ) δ 12.32 (brs, 1H), 8.06 (d, J = 7.6 Hz, 2H), 7.85-7.83
13
Hz, 2H); C NMR (100 MHz, CDCl ) δ 165.3, 150.5, 149.8,
3
6
1
42.8, 139.8, 128.4, 124.0, 110.8, 108.4, 37.4; HRMS Calcd for
(m, 1H), 7.57-7.53 (m, 1H ), 7.43-7.39 (m, 2H), 7.31-7.23 (m,
+
C H N O (M + H ): 247.0713; Found: 247.0717.
13
12 11
2
4
3
H); C NMR (100 MHz, DMSO-d ) δ 166.3, 160.4, 147.5,
6
4
.3.21. 4-Nitrobenzamide (9b)

7
1
13
White solid. Mp: 198.2-201.1 °C; H N
A
M
C
R
C
(4
E
0
P
0
T
M
E
H
D
z, MA
2
N
H)
U
, 2
S
.9
C
5 (
R
t,
I
J
P
= 7.2 Hz, 2H); C NMR (100 MHz, CDCl ) δ
3
T
DMSO-d ) δ 8.29-8.27 (m, 3H), 8.09 (d, J = 8.4 Hz, 2H), 7.73
brs, 1H); C NMR (100 MHz, DMSO-d ) δ 166.3, 149.1,
40.0, 128.9, 123.5; HRMS Calcd for C H N O (M + H ):
164.4, 150.0, 148.1, 139.0, 137.4, 128.9, 128.7, 126.6, 126.2,
6
13
+
(
1
1
122.3, 40.9, 36.0; HRMS Calcd for C H N O (M + H ):
6
14 15
2
+
227.1179; Found: 227.1176.
7
7
2
3
67.0451; Found: 167.0454.
4
.3.29. N-Phenethylnicotinamide (15a)
1
4
.3.22. N-(sec-butyl)-4-nitrobenzamide (9c)
Yellow oil. H NMR (400 MHz, CDCl ) δ 8.79 (s, 1H), 8.60
(d, J = 2.0 Hz, 1H), 8.00 (d, J = 6.8 Hz, 1H), 7.28-7.16 (m, 6H),
6.40 (brs, 1H), 3.65 (d, J = 6.0 Hz, 2H), 2.87 (t, J = 6.0 Hz, 2H);
C NMR (100 MHz, CDCl ) δ 165.6, 152.0, 147.6, 138.7, 135.4,
130.5, 128.9, 128.8, 126.8, 123.7, 41.4, 35.7; HRMS Calcd for
3
1
Yellow solid. Mp: 114.4-117.1 °C; H NMR (400 MHz,
CDCl ) δ 8.28 (d, J = 8.4 Hz, 2H), 7.92 (d, J = 8.4 Hz, 2H), 6.02
d, J = 5.2 Hz, 1H), 4.20-4.09 (m, 1H), 1.65-1.58 (m, 2H), 1.27
d, J = 6.4 Hz, 3H), 0.99 (t, J = 7.6 Hz, 3H); C NMR (100
MHz, CDCl ) δ 165.1, 149.6, 140.7, 128.2, 123.9, 47.9, 29.8,
3
13
(
(
3
1
3
+
C H N O (M + H ): 227.1179; Found: 227.1181.
3
14 15
2
+
2
0.5, 10.6; HRMS Calcd for C H N O (M + H ): 223.1077;
11 15 2 3
4
.3.30. Nicotinamide (15b)
White solid. Mp: 128.3-131.1 °C; H NMR (400 MHz,
DMSO-d ) δ 9.05 (s, 1H), 8.72-8.70 (m, 1H), 8.23-8.21 (m, 1H),
.17 (brs, 1H), 7.61 (brs, 1H), 7.52-7.48 (m, 1H); C NMR (100
MHz, DMSO-d ) δ 166.5, 151.9, 148.7, 135.1, 129.7, 123.4;
Found: 223.1079.
1
4
(
.3.23. (4-Nitrophenyl)(piperidin-1-yl)methanone
9e)
Yellow solid. Mp: 95.4-97.8 °C; H NMR (400 MHz, CDCl )
δ 8.28 (d, J = 8.8 Hz, 2H), 7.57 (d, J = 8.8 Hz, 2H), 3.74 (brs,
H), 3.30 (brs, 2H), 1.71 (brs, 4H), 1.54 (brs, 2H); C NMR
6
13
8
1
3
6
+
HRMS Calcd for C H N O (M + H ): 123.0553; Found:
6
7
2
1
3
2
123.0556.
(
4
2
100 MHz, CDCl ) δ 168.1, 148.3, 142.7, 127.9, 123.9, 48.8,
3.3, 26.6, 25.6, 24.5; HRMS Calcd for C H N O (M + H ):
12 14 2 3
34.0993; Found: 234.0996.
3
+
4.3.31. N-phenethylthiophene-2-carboxamide (16a)
1
Yellow solid. Mp: 138.6-139.8 °C; H NMR (400 MHz,
CDCl ) δ 7.45-7.40 (m, 2H), 7.34-7.28 (m, 2H), 7.26-7.20 (m,
3
4
.3.24. N-phenethyl-2-nitrobenzamide (10a).
3
H), 7.05-7.01 (m, 1H), 6.21 (brs, 1H), 3.67 (q, J = 6.4 Hz, 2H),
1
13
Yellow solid. Mp: 161.2-163.5 °C; H NMR (400 MHz,
2.91 (t, J = 6.4 Hz, 2H); C NMR (100 MHz, CDCl ) δ 162.0,
3
CDCl ) δ 8.51 (t, J = 2.0 Hz, 1H), 8.34 (ddd, J = 8.0, 2.0, 0.8 Hz,
139.2, 138.9, 129.9, 128.9, 128.8, 128.0, 127.7, 126.7, 41.2,
3
+
1
7
H), 8.07 (dt, J = 8.0, 1.2 Hz, 1H), 7.62 (t, J = 8.0 Hz, 1H), 7.36-
.33 (m, 2H), 7.28-7.24 (m, 3H), 6.36 (brs, 1H), 3.76 (q, J = 6.8
35.9; HRMS Calcd for C H NOS (M + H ): 232.0791; Found:
13
14
232.0795.
13
Hz, 2H), 2.97 (t, J = 6.8 Hz, 2H); C NMR (100 MHz, CDCl ) δ
3
4
.3.32. N-phenethylheptanamide (17a)
Yellow solid. Mp: 114.6-116.8 °C; H NMR (400 MHz,
1
1
2
65.3, 148.2, 138.6, 136.3, 133.2, 129.9, 128.9, 128.8, 126.9,
1
+
26.1, 121.9, 41.6, 35.6; HRMS Calcd for C H N O (M + H ):
15
15
2
3
CDCl ) δ 7.34-7.27 (m, 2H), 7.25-7.20 (m, 3H), 6.30 (brs, 1H),
71.1077; Found: 271.1076.
3
3
1
.71 (q, J = 6.4 Hz, 2H), 2.93 (t, J = 6.4 Hz, 2H), 2.04 (brs, 2H),
.53-1.46 (m, 2H), 1.35-1.26 (m, 6H), 0.87 (t, J = 6.4 Hz, 3H);
4
.3.25. Methyl 4-(phenethylcarbamoyl)benzoate
1
3
(
11a)
Yellow solid. Mp: 145.2-148.5 °C; H NMR (400 MHz,
CDCl ) δ 8.07 (d, J = 8.4 Hz, 2H), 7.74 (d, J = 8.4 Hz, 2H), 7.36-
C NMR (100 MHz, CDCl ) δ 167.9, 139.0, 128.7, 127.0, 126.7,
3
1
41.3, 35.8, 35.7, 32.0, 25.8, 23.6, 22.5, 14.1; HRMS Calcd for
+
3
C H NO (M + H ): 234.1852; Found: 234.1855.
15 24
7
3
.32 (m, 2H), 7.28-7.23 (m, 3H), 6.20 (brs, 1H), 3.93 (s, 3H),
.75 (q, J = 6.8 Hz, 2H), 2.95 (t, J = 6.88 Hz, 2H); C NMR
13
4.3.33. N-(pyridin-2-yl)heptanamide (17b).
1
White solid. Mp: 68.5-70.1 °C; H NMR (400 MHz, CDCl ) δ
(
100 MHz, CDCl ) δ 166.8, 166.4, 138.8, 138.6, 132.7, 129.9,
3
3
8
.79 (brs, 1H), 8.27-8.25 (m, 2H), 7.73-7.69 (m, 1H), 7.04 (ddd,
1
28.9, 128.8, 127.0, 126.8, 52.5, 41.4, 35.7; HRMS Calcd for
+
J = 7.2, 4.8, 0.8 Hz, 1H), 2.39 (t, J = 7.2 Hz, 2H), 1.76-1.68 (m,
C H NO (M + H ): 284.1281; Found: 284.1284.
17
18
3
13
2
H), 1.38-1.28 (m, 6H), 0.88 (t, J = 6.8 Hz, 3H); C NMR (100
4
.3.26. N-phenethyl-4-cyanobenzamide (12a)
Yellow solid. Mp: 140.2-142s.6 °C; H NMR (400 MHz,
MHz, CDCl ) δ 172.2, 151.8, 147.6, 138.7, 119.7, 114.4, 37.9,
3
1
31.6, 29.0, 25.5, 22.6, 14.1; HRMS Calcd for C H N O (M +
12
19
2
+
CDCl ) δ 7.78-7.75 (m, 2H), 7.71-7.69 (m, 2H), 7.36-7.32 (m,
H ): 207.1492; Found: 207.1494.
3
2
2
H), 7.28-7.22 (m, 3H), 6.22 (brs, 1H), 3.74 (q, J = 6.8 Hz, 2H),
13
4.3.34. N-(pyridin-2-yl)hexanamide (18a)
.95 (t, J = 6.8 Hz, 2H); C NMR (100 MHz, CDCl ) δ 165.9,
3
1
White oil. H NMR (400 MHz, CDCl ) δ 8.99 (brs, 1H), 8.29
1
4
38.6, 138.5, 132.5, 128.9, 128.8, 127.7, 126.9, 118.1, 115.1,
3
+
(d, J = 8.0 Hz, 1H), 8.22-8.20 (m, 1H), 7.71-7.69 (m, 1H), 7.04
1.5, 35.7; HRMS Calcd for C H N O (M + H ): 251.1179;
16
15
2
(
1
ddd, J = 7.2, 4.8, 0.8 Hz, 1H), 2.42 (t, J = 7.2 Hz, 2H), 1.75-
Found: 251.1180.
13
.68 (m, 2H), 1.38-1.34 (m, 4H), 0.91 (t, J = 7.2 Hz, 3H);
C
4
.3.27. N-phenethyl-4-(trifluoromethyl)benzamide
13a)
White solid. Mp: 153.6-155.8 °C; H NMR (400 MHz,
CDCl ) δ 7.78 (d, J = 8.0 Hz, 2H), 7.64 (d, J = 8.0 Hz, 2H), 7.34-
NMR (100 MHz, CDCl ) δ 172.4, 151.7, 147.0, 139.0, 119.6,
3
(
1
14.4, 37.7, 31.5, 25.2, 22.5, 14.1; HRMS Calcd for C H N O
11 17 2
+
1
(M + H ): 193.1335; Found: 193.1337.
3
7
.31 (m, 2H), 7.27-7.21 (m, 3H), 6.35 (brs, 1H), 3.72 (q, J = 6.4
Acknowledgements
13
Hz, 2H), 2.94 (t, J = 6.4 Hz, 2H); C NMR (100 MHz, CDCl ) δ
3
1
1
66.4, 138.8, 138.0, 133.4, 128.9, 127.4, 126.8, 125.8, 125.7,
25.6, 125.6, 41.4, 35.7; HRMS Calcd for C H F NO (M +
Financial Support from the National Natural Science
Foundation of China (Grant No. 21302013), Suzhou Science and
Technology Project (Grant No. SNG201620) and Natural
Science Foundation of Jiangsu Province (Grant No.
BK20161267) are acknowledged.
16
15 3
+
H ): 294.1100; Found: 294.1104.
4
.3.28. N-phenethylpicolinamide (14a)
1
Yellow solid. Mp: 135.4-137.8 °C; H NMR (400 MHz,
CDCl ) δ 8.52-8.50 (m, 1H), 8.20 (d, J = 8.0 Hz, 1H), 8.16 (brs,
1
1
3
Supplementary data
H), 7.83 (td, J = 7.6, 1.6 Hz, 1H), 7.40 (dd, J = 7.6, 1.2 Hz,
H), 7.33-7.29 (m, 2H), 7.26-7.21 (m, 3H), 3.74 (q, J = 7.2 Hz,

8
Tetrahedron
13
1
A
3
9. Azizi, K.; Karimi, M.; Nikbakht, F.; Heydari, A. Applied
Characterization data and copies of the
H
C
N
C
M
E
R
P
an
T
d
ED MANUSCRIPT
C
Catalysis A: Gen. 2014, 482, 336–343.
NMR spectra for all final products can be found at
http://dx.doi.org/XXXXXXXXXXXX.
4
4
0. Yu, H.; Zhang, Y. Eur. J. Org. Chem. 2015, 1824–1828.
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Adv. 2013, 3, 21306–21310.
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