An efficient copper-catalyzed N-arylation of amides: Synthesis of N-arylacrylamides and 4-amido-N-phenylbenzamides

Article abstract of DOI:10.1016/j.tet.2013.07.073

Copper-catalyzed intermolecular C-N bond-forming reactions between aryl iodides and amides are described using sodium ascorbate, which is both cheap and nontoxic, as the additive. A variety of functionalized amides including some practical, unique secondary amides, such as N-arylacrylamides and 4-amido-N-phenylbenzamides, which are difficult to obtain by the classical methods, are prepared. Furthermore, some tertiary amides are prepared by using copper thiophenecarboxylate.

Full text of DOI:10.1016/j.tet.2013.07.073

Tetrahedron 69 (2013) 8368e8374
Contents lists available at SciVerse ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
An efficient copper-catalyzed N-arylation of amides: synthesis of
N-arylacrylamides and 4-amido-N-phenylbenzamides
,
b
,
a
,
,
,
,b,
*
Zheng-Jun Quan a , Hai-Dong Xia b, Zhang Zhang a b, Yu-Xia Da a b, Xi-Cun Wang a
*
a Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education, China, Gansu 730070, PR China
b Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Northwest Normal University, Anning East Road 967#,
Lanzhou, Gansu 730070, PR China
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 17 April 2013
Received in revised form 12 July 2013
Accepted 22 July 2013
Available online 31 July 2013
Copper-catalyzed intermolecular CeN bond-forming reactions between aryl iodides and amides are
described using sodium ascorbate, which is both cheap and nontoxic, as the additive. A variety of
functionalized amides including some practical, unique secondary amides, such as N-arylacrylamides
and 4-amido-N-phenylbenzamides, which are difficult to obtain by the classical methods, are prepared.
Furthermore, some tertiary amides are prepared by using copper thiophenecarboxylate.
Ó 2013 Elsevier Ltd. All rights reserved.
Keywords:
Copper
N-Arylation
Amides
Aryl iodides
CeN cross-coupling
1. Introduction
substrate scope, and the moderate yields obtained.12 These trans-
formations usually require high temperature, long reaction time,
N-Arylamides are important structural motifs found in numer-
ous natural products, which had great influences on the fields of
pharmaceutical, biological, and material sciences.1 Based on the
extensive importance, both classical Ullmann coupling processes2,3
and the related Goldberg coupling reaction4,5 have been commonly
used in laboratory and industrial scale. Transition metal-catalyzed
N-arylation of amides constitutes a powerful CeN bond-forming
process in organic synthesis.6 Since Shakespeare’s first report on
Pd-catalyzed amide arylation,7 many Pd-based catalytic systems
have been developed for the coupling of amides with aryl sulfo-
nates,8 aryl bromides,9 and more recently, aryl chlorides,10 which
proved to be useful to synthetic chemists. However, copper medi-
ated coupling is still the reaction of choice for large and industrial-
scale production owing to an economic attractiveness and various
types of copper-catalyzed systems have been developed.11
expensive and sophisticated supporting ligands, and large amounts
of copper reagents. Thus, careful choice of the additive allowing
condensations to be run at relatively low temperatures and in short
time constitutes an area of considerable interest. More recently, we
have reported the Cu(I) generated in situ from Cu(II)/sodium
ascorbate catalyzed the click reaction13a and amination of aryl
halides with aqueous ammonia.13b Herein we present the
CuSO4$5H2O/sodium ascorbate (NaAsc)-catalyst systems for the
arylation of amides. What’s more, a cheap, simple and less toxic
NaAsc has superiority contrasting with other expensive, sophisti-
cated, and toxic ligands. And above all, we prepared some practical
and unique secondary amide derivatives, such as N-phenyl-
acrylamide (3a), 1-phenylthiourea (5r), benzamido-N-phenyl-
benzamide (5s), and 4-acetamido-N-phenylbenzamide (5t), which
are difficult to obtain by the classical methods. Furthermore, some
tertiary amides are prepared by using copper(I) thiophenecarbox-
ylate (CuTC).
Until recently, copper-catalyzed arylation of amides has not
been employed to their full potential for a long time. Because the
amides are less nucleophilic due to their electron-withdrawing
carbonyl groups, they suffered from reduced synthetic scope as
a result of the harsh reaction conditions often required, a limited
2. Results and discussion
Usually, the analogues of N-phenylacrylamide are obtained by
the classical procedure using acryloyl chloride,14 however, acryloyl
chloride is prepared by using the toxic thionyl chloride and it is
also toxic itself. Based on the above facts, iodobenzene (1a) and
* Corresponding authors. Tel./fax: þ86 931 7972626; e-mail addresses:
quanzhengjun@hotmail.com (Z.-J. Quan), wangxicun@nwnu.edu.cn (X.-C. Wang).
0040-4020/$ e see front matter Ó 2013 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.tet.2013.07.073

Z.-J. Quan et al. / Tetrahedron 69 (2013) 8368e8374
8369
acrylamide (2a) were chosen as model substrates for initial opti-
mization of the reaction conditions (Table 1). The model reaction
gave the N-aryl product 3a in low yields of 20% and 17% in DMSO at
100 ꢀC with CuI and CuSO4$5H2O as the catalysts (entries 1 and 2).
Recently, studies revealed that bidentate additives such as carbonyl
compound,15 diamines,11f and bidentate phosphines16 could pro-
mote the Ullmann and Goldberg coupling reactions. Thus, the ad-
ditives L1eL6 (Fig. 1) were examined. Improved yields were
obtained when NaAsc L1 was screened as the additive using
CuSO4$5H2O (entry 3). Other additives L2eL5 were evaluated and
we found that L2eL5 did not effectively help copper salts to im-
prove the yield of 3a (entries 4e7). Using PPh3 (L6) as additive gave
slightly promoted yields of 3a (entries 8 and 9). Among the copper
salts screened, CuSO4$5H2O proved to be the best in the presence of
t-BuONa as the base at 100 ꢀC for 7 h and afforded the product in
a good yield of 62% (entries 10 and 11). When the reaction time was
increased to 12 h, the 3a yield was not significantly improved by
using CuSO4$5H2O (10 mol %)/L1 (20 mol %), however, a by-product
was detected by TLC (entry 12). As expected, no product was
detected in the absence of copper salts, verifying the importance of
a copper catalyst (entry 13). After screening the amounts of
CuSO4$5H2O/NaAsc-catalyst systems, it was observed that
0.15 equiv of CuSO4$5H2O and 0.3 equiv of NaAsc were the best
(entries 14 and 15). Next, the effect of base was investigated, and t-
BuONa was found to be critical to the reaction, as it furnished the N-
phenylacrylamide (3a) product in a good yield of 71% (entries
14e17). Among various solvents tested, DMSO was the best for the
reaction (entries 18 and 19). We then examined the reaction tem-
perature and found that low temperature decelerated the reaction
rate giving a lower yield (entry 20). Meanwhile, increasing the re-
action temperature to 120 ꢀC did not improve the yield, which
might be due to the thermal polymerization of acrylamide at higher
reaction temperatures (entry 21). Time is also an important factor
to affect the 3a yield. Reducing time to 6 h led to a decrease in the
product yield of 65% and increasing time to 8 h did not effectively
improve the yield (entries 22 and 23). In summary, the optimal
conditions for the cross-coupling reaction of amides with aryl io-
dides were achieved by using a combination of CuSO4$5H2O
(0.15 mmol), NaAsc (0.3 mmol), and t-BuONa (2 mmol) in DMSO at
100 ꢀC for 7 h.
NH2
O
OH
O
OH
HO
O
N
S
HO
O
O
H2N
PPh3
O
Na
O
N
H
O
L1
L2
L6
L3
L4
L5
Fig. 1. Amidation additives.
To study the scope of the procedure, the reaction of acrylamide
(2a) with substituted aryl iodides was examined at the optimal
conditions. As can be seen from Table 2, a range of substituted aryl
iodides could be coupled with acrylamide (2a) to give the desired
products (3aeg) in good yields (entries 1e7). To date, the con-
struction of such amides by Cu-catalyzed cross-coupling is rare.17 In
the present protocol, aryl iodides bearing electron-withdrawing
groups such as fluoro, chloro, and bromo afforded relatively
lower yields (entries 2e4), while aryl iodides bearing electron-
donating groups such as methyl and methoxyl gave the desired
product in a higher yield (entries 5 and 6). It was observed that aryl
iodides bearing ortho-substituent still exhibited high reactivity
with the desired product 3g being isolated in a good yield (entry 7).
Table 1
Optimization of reaction conditions for the N-arylation of acrylamide (2a) with io-
dobenzene (1a)a
I
H
Table 2
O
N
CuSO4$5H2O/NaAsc-catalyzed coupling of aryl iodides with acrylamidea
catalyst, base
solvent
I
NH2
O
O
O
CuSO4·5H2O/NaAsc, t-BuONa
R
1a
2a
3a
N
H
NH2
DMSO, 100 oC, 7 h
R
Entry Catalysts (mol %)
Base
Solvent Temp Time Yieldb
1a-g
2a
3a-g
(ꢀC)
(h)
(%)
1
2
3
4
5
6
7
8
CuI (10)
CuSO4$5H2O (10)
t-BuONa DMSO
t-BuONa DMSO
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
7
7
7
7
7
7
7
7
7
7
7
12
7
7
7
7
7
7
7
7
7
6
8
20
17
62
25
18
19
17
23
45
60
52
63
0
71
71
49
53
61
57
63
70
65
71
Entry
R
Acrylamide
Product
Yieldb (%)
1
2
3
4
5
6
7
H (1a)
4-F (1b)
4-Cl (1c)
4-Br (1d)
4-Me (1e)
4-MeO (1f)
2-Me (1g)
2a
2a
2a
2a
2a
2a
2a
3a
3b
3c
3d
3e
3f
71
60
62
65
69
70
66
CuSO4$5H2O (10)/L1 (20) t-BuONa DMSO
CuSO4$5H2O (10)/L2 (20) t-BuONa DMSO
CuSO4$5H2O (10)/L3 (20) t-BuONa DMSO
CuSO4$5H2O (10)/L4 (20) t-BuONa DMSO
CuSO4$5H2O (10)/L5 (20) t-BuONa DMSO
CuSO4$5H2O (10)/L6 (20) t-BuONa DMSO
CuI (10)/L6 (20)
CuI (10)/L1 (20)
Cu(OAc)2 (10)/L1 (20)
CuSO4$5H2O (10)/L1 (20) t-BuONa DMSO
L1 (20) t-BuONa DMSO
CuSO4$5H2O (15)/L1 (30) t-BuONa DMSO
CuSO4$5H2O (20)/L1 (40) t-BuONa DMSO
CuSO4$5H2O (15)/L1 (30) K2CO3
CuSO4$5H2O (15)/L1 (30) K3PO4
CuSO4$5H2O (15)/L1 (30) t-BuONa Toluene 100
CuSO4$5H2O (15)/L1 (30) t-BuONa Dioxane 100
CuSO4$5H2O (15)/L1 (30) t-BuONa DMSO
CuSO4$5H2O (15)/L1 (30) t-BuONa DMSO
CuSO4$5H2O (15)/L1 (30) t-BuONa DMSO
CuSO4$5H2O (15)/L1 (30) t-BuONa DMSO
3g
9
t-BuONa DMSO
t-BuONa DMSO
t-BuONa DMSO
a
Reaction conditions: aryl iodides (1.0 mmol), acrylamide (1.2 mmol),
CuSO4$5H2O (0.15 mmol)/NaAsc (0.3 mmol), t-BuONa (2.0 mmol), DMSO (3.0 mL),
100 ꢀC, 7 h.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
b
Isolated yield.
DMSO
DMSO
To further expand the scope of substrates, aromatic amides, such
as benzamide (4a), 3-nitrobenzamide (4b), 4-iodobenzamide (4c),
and 3-methylbenzamide (4d), were exposed to the standard re-
action conditions resulting in the formation of the CeN cross-
coupling reaction products (Table 3, entries 1e9). In addition, ali-
phatic amides such as acetamide (4e) and 2-phenylacetamide (4f)
were also adapted to the reaction to give the N-arylation products
in good yields (entries 10e17). We were pleased to find that the
reaction of thiourea (4g) with iodobenzene was achieved by
80
120
100
100
a
Reaction conditions: iodobenzene (1a, 1.0 mmol), acrylamide (2a, 1.2 mmol),
base (2.0 mmol), solvent (3.0 mL), 100 ꢀC.
b
Isolated yield.

8370
Z.-J. Quan et al. / Tetrahedron 69 (2013) 8368e8374
elevating the temperature to 130 ꢀC and extending the time to 12 h,
and afforded the product of 1-phenylthiourea (5r), which is an
important organic synthetic intermediate (entry 18). Furthermore,
the cross-coupling reactions of 4-iodo-N-phenylbenzamide (5h)
with amides (4a and 4e) were conducted successfully to afford the
thrilling products 5s and 5t (entries 19 and 20). The resulting sec-
ondary amides were difficult to obtain by classical methods be-
cause of protection and deprotection of amino required in the
operation.
coupling.8g Until recently, only few isolated examples involving
either palladium or copper as catalysts have been described for
secondary amides.11b,f,19 When secondary amides such as 5j and N-
methylbenzamide (7a) were used under the above optimal condi-
tions, no reaction occurred and the starting materials were ob-
tained. To our delight, when CuTC was used as the copper source;
the reaction of 5j with iodobenzene (1a) afforded a 67% yield of the
tertiary amide (8a) by the N-arylation reaction. Similarly, the re-
actions of 7a, N-methyl-2-phenylacetamide (7b), and azepan-2-one
(7c) with 1a yielded the tertiary amides (8bed) in 61e69%
yield (Scheme 2).
Table 3
N-Arylation of amides with aryl iodidesa
I
O
O
CuSO4·5H2O/NaAsc, t-BuONa
R1
1a-g, 5h
R2
NH2
R2
N
H
R1
DMSO, 100 oC, 7 h
4a-g
5a-t
Entry
Aryl iodides
R2
Product
Yieldb (%)
Scheme 2. CuTC-catalyzed N-arylation of secondary amides.
1
2
3
4
5
6
7
8
1a
1b
1d
1e
1f
1g
1a
1a
1a
1a
1b
1c
1d
1e
1f
Ph (4a)
Ph (4a)
Ph (4a)
Ph (4a)
Ph (4a)
Ph (4a)
3-NO2 (4b)
4-IC6H4 (4c)
3-MeC6H4 (4d)
Me (4e)
Me (4e)
Me (4e)
Me (4e)
Me (4e)
Me (4e)
Me (4e)
PhCH2 (4f)
Thiourea (4g)
Ph (4a)
5a
5b
5c
5d
5e
5f
5g
5h
5i
83
73
75
80
82
78
65
76
81
77
65
67
70
75
78
73
72
55c
65c
63c
Cohen first proposed the intervention of the oxidative addition/
reductive elimination mechanism in Ullmann condensations in
1974.20 Next, several literature reports substantiated this mecha-
nism indicating CuI and CuIII intermediates.21 What’s more, Cristau
explained the mechanism in detail.22 Thus, a possible rationale was
proposed based on above reports (Scheme 3). Cu(I) was generated
in situ from Cu(OAc)2$H2O/sodium ascorbate. Firstly, Cu(I) was
generated in situ from CuSO4$5H2O/NaAsc. Then, nucleophilic
substitution of Cu(I) by amide anion leads to the formation of the
intermediate A, and oxidative addition of the aryl halide to A
generates a transient CuIII species (B). Finally, the CeN bond
product is formed by reductive elimination from B and the initial
copper(I) species are regenerated.
9
10
11
12
13
14
15
16
17
18
19
20
5j
5k
5l
5m
5n
5o
5p
5q
5r
5s
5t
1g
1a
1a
5h
5h
Me (4e)
a
Reaction conditions: aryl iodides (1.0 mmol), amides (1.2 mmol), CuSO4$5H2O
(0.15 mmol)/NaAsc (0.3 mmol), t-BuONa (2.0 mmol), DMSO (3.0 mL), 100 ꢀC, 7 h.
NaAsc
b
O
Isolated yield.
c
At 130 ꢀC, 12 h.
O
Cu2
O
R2
NH2
t-BuONa
R2
N
H
R2
NH
t-BuOH
R1
Cu
Unfortunately, the coupling reaction of 4-iodo-N-phenyl-
benzamide (5h) with acrylamide (2a) could not successfully pro-
ceed to afford the desired product at 100 ꢀC for 7 h. However, the
coupling reaction of 5h with 2a afforded the product 6a when the
reaction was carried out at 130 ꢀC for 12 h (Scheme 1), and acryloyl
group was dissociated in the process. Next, the reaction of 2a with
4-iodo-N-m-tolylbenzamide (5u) was carried out to afford 4-
amino-N-m-tolylbenzamide (6b), which further confirmed that
acryloyl group was dissociated in the reaction18 (Scheme 1).
O
O
Cu3
R2
R2
Cu
NH
A
HN
I
R1
B
I
R1
Scheme 3. A possible rationale for the copper-catalyzed N-arylation of amides.
NH2
I
CuSO4·5H2O/NaAsc
O
3. Conclusions
H
N
H
N
t-BuONa, DMSO
NH2
130 oC, 12 h
O
O
In conclusion, we have developed a simple, novel and efficient
method for N-arylation of amides by using a copper/NaAsc catalyst
system. The easy use of nontoxic L-ascorbic acid sodium salt, and
R
R
6
5
2a
R = H (6a), 60%; R = 3-CH3 (6b), 62%
R = H (5h); R = 3-CH3 (5u)
the low cost and environmentally benign character of the catalytic
system (CuSO4$5H2O/NaAsc) are great advantages in terms of in-
dustrial scale and green chemistry. Furthermore, some novel
structures of secondary amides difficultly obtained by the classical
methods are prepared, which make this approach attractive.
Meanwhile, some tertiary amides are prepared by using CuTC as the
catalyst.
Scheme 1. The cross-coupling reaction of acrylamide with 4-iodo-N-
phenylbenzamide.
The large size of secondary amides,9a combined with their rel-
atively low nucleophilicity (compared to amines), has made sec-
ondary amides a particularly challenging substrate class for cross-

Z.-J. Quan et al. / Tetrahedron 69 (2013) 8368e8374
8371
4. Experimental section
4.1. General
C9H8BrNO 225.9868, found 225.9871. Anal. Calcd for C9H8BrNO
(224.98): C, 47.82; H, 3.57; N, 6.20. Found: C, 47.90; H, 3.36; N, 6.59.
4.2.5. N-p-Tolylacrylamide (3e). White solid, mp 144e145 ꢀC; yield:
All reactions were carried out under air in oven-dried glass-
ware with magnetic stirring. All materials were obtained from
commercial suppliers and were used without further purifica-
tion. Unless otherwise noted, organic extracts were dried with
Na2SO4, filtered through a fritted glass funnel, and concentrated
with a rotary evaporator. Flash chromatography was performed
with silica gel (200e300 mesh) using the mobile phase in-
dicated. Melting points were determined on an XT-4 electro-
thermal micromelting point apparatus and uncorrected. NMR
spectra were recorded for 1H NMR (400 MHz) and 13C NMR
(100 MHz), using TMS as internal standard. Mass-spectra were
recorded on a Bruker APEXII instrument. Elemental analyses
69% (ethyl acetate/petroleum ether: 1:3); 1H NMR (400 MHz,
CDCl3)
d
¼7.94 (s, 1H, NH), 7.40 (d, J¼8.4 Hz, 2H, ArH), 7.02 (d,
J¼8.0 Hz, 2H, ArH), 6.34e6.18 (m, 2H, CH2), 5.63e5.60 (m, 1H, CH),
2.23 (s, 3H, CH3); 13C NMR (100 MHz, CDCl3)
d¼163.74, 135.19,
134.09, 131.26, 129.39, 127.36, 120.18, 20.84; HRMS [MþH]þ calcd
for C10H11NO 162.0919, found 162.0917. Anal. Calcd for C10H11NO
(161.08): C, 74.51; H, 6.88; N, 8.69. Found: C, 74.62; H, 6.84; N, 8.77.
4.2.6. N-(4-Methoxyphenyl)acrylamide (3f). White solid, mp
163e165 ꢀC; yield: 70% (ethyl acetate/petroleum ether: 2:1); 1H
NMR (400 MHz, DMSO-d6)
d
¼9.78 (s, 1H, NH), 7.49 (d, J¼8.8 Hz, 2H,
ArH), 6.85 (d, J¼8.8 Hz, 2H, ArH), 6.23e6.05 (m, 2H, CH2), 5.57e5.54
were performed on
instrument.
a Carlo-Erba 1106 Elemental Analysis
(m, 1H, CH), 3.70 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6)
d
¼169.29, 165.15, 155.53, 132.20, 125.46, 121.08, 114.22, 55.59;
HRMS [MþH]þ calcd for C10H11NO2 178.0868, found 178.0870. Anal.
Calcd for C10H11NO2 (177.08): C, 67.78; H, 6.26; N, 7.90. Found: C,
67.89; H, 6.15; N, 8.05.
4.2. General procedure for N-arylation of primary amides
CuSO4$5H2O (0.15 mmol), NaAsc (0.3 mmol), aryl iodides
(1 mmol), primary amides (1.2 mmol), t-BuONa (2.0 mmol), and
DMSO (3 mL) were added to a flask. The reaction mixture was
stirred under air, and then cooled to room temperature and
extracted with ethyl acetate (3ꢁ10 mL). The organic layer was then
dried over anhydrous Na2SO4, and the solvent was removed under
reduced pressure. The secondary amides were finally obtained by
column chromatography on silica gel eluted with ethyl acetate/
petroleum ether.
4.2.7. N-o-Tolylacrylamide (3g). White solid, mp 110e112 ꢀC; yield:
66% (ethyl acetate/petroleum ether: 1:4); 1H NMR (400 MHz,
CDCl3)
d
¼7.70 (d, J¼6.0 Hz, 1H, NH), 7.33 (s, 1H, ArH), 7.10 (t,
J¼7.4 Hz, 2H, ArH), 7.01 (d, J¼7.2 Hz, 1H, ArH), 6.33e6.18 (m, 2H,
CH2), 5.64 (d, J¼11.2 Hz, 1H, CH), 2.16 (s, 3H, CH3); 13C NMR
(100 MHz, CDCl3)
d
¼163.79, 135.31, 131.06, 130.39, 129.71, 127.37,
126.54, 125.40, 123.53, 17.72; HRMS [MþH]þ calcd for C10H11NO
162.0919, found 162.0922. Anal. Calcd for C10H11NO (161.08): C,
74.51; H, 6.88; N, 8.69. Found: C, 74.62; H, 6.77; N, 8.84.
4.2.1. N-Phenylacrylamide (3a). White solid, mp 103e104 ꢀC;
yield: 71% (ethyl acetate/petroleum ether: 1:5); 1H NMR
4.2.8. N-Phenylbenzamide (5a).10a White solid, mp 160e162 ꢀC;
(400 MHz, CDCl3)
d
¼8.00 (s, 1H, NH), 7.52 (d, J¼7.6 Hz, 2H, ArH),
yield: 83% (ethyl acetate/petroleum ether: 1:7); 1H NMR (400 MHz,
7.23 (t, J¼7.8 Hz, 2H, ArH), 7.03 (t, J¼7.4 Hz, 1H, ArH), 6.37e6.20
CDCl3)
d
¼7.81 (s, 1H, NH), 7.79 (d, J¼1.6 Hz, 2H, ArH), 7.58 (d,
(m, 2H, CH2), 5.66e5.63 (m, 1H, CH); 13C NMR (100 MHz, CDCl3)
J¼7.6 Hz, 2H, ArH), 7.51e7.47 (m, 1H, ArH), 7.44e7.40 (m, 2H, ArH),
d
¼163.87, 137.72, 131.16, 128.91, 127.71, 124.48, 120.13; HRMS
7.31 (t, J¼8.0 Hz, 2H, ArH), 7.09 (t, J¼7.4 Hz, 1H, ArH); 13C NMR
[MþH]þ calcd for C9H9NO 148.0762, found 148.0760. Anal. Calcd
for C9H9NO (147.07): C, 73.45; H, 6.16; N, 9.52. Found: C, 73.52; H,
6.15; N, 9.48.
(100 MHz, CDCl3)
d¼165.64, 137.87, 134.32, 131.79, 129.06, 128.76,
126.95, 124.53, 120.13; HRMS [MþH]þ calcd for C13H11NO 198.0919,
found 198.0917. Anal. Calcd for C13H11NO (197.08): C, 79.16; H, 5.62;
N, 7.10. Found: C, 79.31; H, 6.99; N, 7.31.
4.2.2. N-(4-Fluorophenyl)acrylamide
148e150 ꢀC; yield: 60% (ethyl acetate/petroleum ether: 1:4); 1H
NMR (400 MHz, DMSO-d6)
¼10.23 (s, 1H, NH), 7.72e7.69 (m, 2H,
ArH), 7.18 (t, J¼8.4 Hz, 2H, ArH), 6.44e6.25 (m, 2H, CH2), 5.78e5.75
(3b). White
solid,
mp
4.2.9. N-(4-Fluorophenyl)benzamide (5b).11a White solid, mp
185e187 ꢀC; yield: 73% (ethyl acetate/petroleum ether: 1:7); 1H
d
NMR (400 MHz, DMSO-d6)
d
¼10.32 (s,1H, NH), 7.79 (t, J¼4.2 Hz, 2H,
(m, 1H, CH); 13C NMR (100 MHz, DMSO-d6)
d¼163.02, 156.91,
ArH), 7.82e7.78 (m, 2H, ArH), 7.60e7.50 (m, 3H, ArH), 7.19 (t,
135.42, 131.71, 126.95, 121.08, 121.00, 115.47, 115.25; HRMS [MþH]þ
calcd for C9H8FNO 166.0668, found 166.0670. Anal. Calcd for
C9H8FNO (165.06): C, 65.45; H, 4.88; N, 8.48. Found: C, 65.53; H,
4.78; N, 8.99.
J¼8.8 Hz, 2H, ArH); 13C NMR (100 MHz, DMSO-d6)
¼165.47, 159.47,
d
135.55, 134.81, 131.60, 128.40, 127.64, 122.19, 122.12, 115.30, 115.08;
HRMS [MþH]þ calcd for C13H10FNO 216.0825, found 216.0828.
Anal. Calcd for C13H10FNO (215.07): C, 72.55; H, 4.68; N, 6.51. Found:
C, 72.67; H, 4.62; N, 6.64.
4.2.3. N-(4-Chlorophenyl)acrylamide
190e192 ꢀC; yield: 62% (ethyl acetate/petroleum ether: 1:4); 1H
NMR (400 MHz, DMSO-d6)
¼10.31 (s, 1H, NH), 7.72 (d, J¼8.8 Hz,
2H, ArH), 7.39 (d, J¼8.8 Hz, 2H, ArH), 6.47e6.26 (m, 2H, CH2),
(3c). White
solid,
mp
4.2.10. N-(4-Bromophenyl)benzamide (5c).11g White solid, mp
198e199 ꢀC; yield: 75% (ethyl acetate/petroleum ether: 1:10); 1H
d
NMR (400 MHz, DMSO-d6)
d
¼10.38 (s,1H, NH), 7.93 (t, J¼2.8 Hz, 2H,
5.80e5.77 (m, 1H, CH); 13C NMR (100 MHz, DMSO-d6)
d
¼163.23,
ArH), 7.78e7.75 (m, 2H, ArH), 7.67e7.57 (m, 2H, ArH), 7.54e7.51 (m,
137.98, 131.62, 128.72, 127.32, 127.07, 120.85; HRMS [MþH]þ calcd
for C9H8ClNO 182.0373, found 182.0370. Anal. Calcd for C9H8ClNO
(181.03): C, 59.52; H, 4.44; N, 7.71. Found: C, 59.60; H, 4.35; N, 7.80.
3H, ArH); 13C NMR (100 MHz, DMSO-d6)
d
¼165.66, 138.58, 137.28,
134.70, 131.45, 128.44, 127.69, 122.19, 115.33; HRMS [MþH]þ calcd
for
C13H10BrNO 276.0024, found 276.0026. Anal. Calcd for
C13H10BrNO (274.99): C, 56.55; H, 3.65; N, 5.07. Found: C, 56.68; H,
4.2.4. N-(4-Bromophenyl)acrylamide (3d). White solid, mp
170e171 ꢀC; yield: 65% (ethyl acetate/petroleum ether: 1:4); 1H
3.56; N, 5.22.
NMR (400 MHz, DMSO-d6)
d
¼10.29 (s, 1H, NH), 7.65 (d, J¼8.8 Hz,
4.2.11. N-p-Tolylbenzamide (5d).11g White solid, mp 154e155 ꢀC;
2H, ArH), 7.51 (d, J¼9.2 Hz, 2H, ArH), 6.46e6.25 (m, 2H, CH2),
yield: 80% (ethyl acetate/petroleum ether: 1:10); 1H NMR
5.80e5.77 (m, 1H, CH); 13C NMR (100 MHz, DMSO-d6)
d
¼163.20,
(400 MHz, CDCl3)
7.45e7.42 (m, 3H, ArH), 7.38e7.34 (m, 2H, ArH), 7.07 (d, J¼8.4 Hz,
d
¼7.88 (s, 1H, NH), 7.76 (t, J¼4.2 Hz, 2H, ArH),
138.34, 131.58, 127.31, 121.19, 115.08; HRMS [MþH]þ calcd for

8372
Z.-J. Quan et al. / Tetrahedron 69 (2013) 8368e8374
2H, ArH), 2.25 (s, 3H, CH3); 13C NMR (100 MHz, CDCl3)
d¼165.70,
NMR (400 MHz, CDCl3)
d
¼7.56 (s, 1H, NH), 7.40e7.36 (m, 2H, ArH),
135.30, 134.97, 134.13, 131.63, 129.48, 128.63, 126.96, 120.29, 20.87;
HRMS [MþH]þ calcd for C14H13NO 212.1075, found 212.1073. Anal.
Calcd for C14H13NO (211.10): C, 79.59; H, 6.20; N, 6.63. Found: C,
79.69; H, 6.11; N, 6.76.
6.92 (t, J¼8.6 Hz, 2H, ArH), 2.09 (s, 3H, CH3); 13C NMR (100 MHz,
CDCl3)
d
¼168.55, 158.11, 133.79, 121.86, 121.79, 115.66, 115.44,
24.31; HRMS [MþH]þ calcd for C8H8FNO 154.0668, found 154.0671.
Anal. Calcd for C8H8FNO (153.06): C, 62.74; H, 5.26; N, 9.15. Found:
C, 62.83; H, 5.16; N, 9.22.
4.2.12. N-(4-Methoxyphenyl)benzamide (5e). White solid, mp
164e165 ꢀC; yield: 82% (ethyl acetate/petroleum ether: 1:7); 1H
4.2.19. N-(4-Chlorophenyl)acetamide
184e185 ꢀC; yield: 67% (ethyl acetate/petroleum ether: 1:2); 1H
NMR (400 MHz, DMSO-d6)
¼10.08 (s, 1H, NH), 7.62e7.59 (m, 2H,
ArH), 7.34e7.32 (m, 2H, ArH), 2.04 (s, 3H, CH3); 13C NMR (100 MHz,
(5l). White
solid,
mp
NMR (400 MHz, DMSO-d6)
d
¼10.12 (s, 1H, NH),7.94 (t, J¼4.2 Hz, 2H,
ArH), 7.68 (d, J¼9.2 Hz, 2H, ArH), 7.57e7.49 (m, 3H, ArH), 6.92 (d,
d
J¼9.2 Hz, 2H, ArH), 3.74 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6)
d¼165.57, 156.01, 135.52, 132.70, 131.81, 128.79, 128.00, 122.44,
DMSO-d6)
d¼168.43, 138.27, 128.56, 126.48, 120.44, 24.00; HRMS
114.19, 55.63; HRMS [MþH]þ calcd for C14H13NO2 228.1025, found
228.1027. Anal. Calcd for C14H13NO2 (227.09): C, 73.99; H, 5.77; N,
6.16. Found: C, 74.10; H, 5.68; N, 6.28.
[MþH]þ calcd for C8H8ClNO 170.0373, found 170.0370. Anal. Calcd
for C8H8ClNO (169.03): C, 56.65; H, 4.75; N, 8.26. Found: C, 56.72; H,
4.68; N, 8.30.
4.2.13. N-o-Tolylbenzamide (5f).11g White solid, mp 138e140 ꢀC;
4.2.20. N-(4-Bromophenyl)acetamide (5m).11g White solid, mp
164e165 ꢀC; yield: 70% (ethyl acetate/petroleum ether: 1:2); 1H
yield: 78% (ethyl acetate/petroleum ether: 1:7); 1H NMR (400 MHz,
CDCl3)
d
¼7.85e7.79 (m, 3H, ArH), 7.66 (s, 1H, NH), 7.48 (t, J¼7.2 Hz,
NMR (400 MHz, DMSO-d6)
d
¼10.07 (s,1H, NH), 7.54 (t, J¼4.6 Hz, 2H,
1H, ArH), 7.40 (t, J¼7.4 Hz, 2H, ArH), 7.19e7.14 (m, 2H, ArH), 7.04 (t,
ArH), 7.45 (t, J¼4.4 Hz, 2H, ArH), 2.02 (s, 3H, CH3); 13C NMR
J¼7.4 Hz, 1H, ArH), 2.25 (s, 3H, CH3); 13C NMR (100 MHz, CDCl3)
(100 MHz, DMSO-d6)
d
¼168.52, 138.69, 131.50, 120.86, 114.51,
d
¼165.61, 135.73, 134.95, 131.77, 130.50, 129.32, 128.76, 127.01,
24.06; HRMS [MþH]þ calcd for C8H8BrNO 213.9868, found
213.9870. Anal. Calcd for C8H8BrNO (212.98): C, 44.89; H, 3.77; N,
6.54. Found: C, 45.00; H, 3.67; N, 6.63.
126.83, 125.33, 123.17, 17.79; HRMS [MþH]þ calcd for C14H13NO
212.1075, found 212.1077. Anal. Calcd for C14H13NO (211.10): C,
79.59; H, 6.20; N, 6.63. Found: C, 79.70; H, 6.11; N, 6.75.
4.2.21. N-p-Tolylacetamide (5n).11g White solid, mp 147e149 ꢀC;
4.2.14. 3-Nitro-N-phenylbenzamide
225e227 ꢀC; yield: 65% (ethyl acetate/petroleum ether: 1:5); 1H
NMR (400 MHz, CDCl3)
(5g). White
solid,
mp
yield: 75% (ethyl acetate/petroleum ether: 1:2); 1H NMR (400 MHz,
CDCl3)
d
¼7.73 (s, 1H, NH), 7.30 (d, J¼8.4 Hz, 2H, ArH), 7.02 (d,
d¼8.62 (s, 1H, ArH), 8.32 (t, J¼4.0 Hz, 1H,
J¼8.0 Hz, 2H, ArH), 2.23 (s, 3H, CH3), 2.06 (s, 3H, CH3); 13C NMR
ArH), 8.18 (d, J¼7.6 Hz, 1H, ArH), 8.00 (s, 1H, NH), 7.63e7.57 (m, 3H,
(100 MHz, CDCl3)
d
¼168.60, 135.32, 133.84, 129.33, 120.13, 24.30,
ArH), 7.31 (t, J¼8.0 Hz, 2H, ArH), 7.12 (t, J¼7.4 Hz, 1H, ArH); 13C NMR
20.79; HRMS [MþH]þ calcd for C9H11NO 150.0919, found 150.0917.
Anal. Calcd for C9H11NO (149.08): C, 72.46; H, 7.43; N, 9.39. Found:
C, 72.50; H, 7.35; N, 9.47.
(100 MHz, DMSO-d6)
d¼158.83,143.23,134.18,131.78,129.70,125.71,
124.22, 121.69, 119.66, 117.93, 116.06; HRMS [MþH]þ calcd for
C13H10N2O 243.0770, found 243.0773. Anal. Calcd for C13H10N2O
(210.08): C, 74.27; H, 4.79; N,13.33. Found: C, 74.35; H, 4.69; N,13.45.
4.2.22. N-(4-Methoxyphenyl)acetamide (5o). White solid, mp
128e130 ꢀC; yield: 78% (ethyl acetate/petroleum ether: 1:2); 1H
4.2.15. 4-Iodo-N-phenylbenzamide
210e212 ꢀC; yield: 76% (ethyl acetate/petroleum ether: 1:8); 1H
NMR (400 MHz, DMSO-d6)
¼10.29 (s, 1H, NH), 7.91 (d, J¼8.4 Hz,
(5h). White
solid,
mp
NMR (400 MHz, DMSO-d6)
d
¼9.77 (s, 1H, NH), 7.48 (d, J¼9.2 Hz, 2H,
ArH), 6.86 (d, J¼9.2 Hz, 2H, ArH), 3.71 (s, 3H, CH3), 2.01 (s, 3H, CH3);
d
13C NMR (100 MHz, DMSO-d6)
d¼168.16, 155.46, 132.99, 120.98,
2H, ArH), 7.76e7.73 (m, 4H, ArH), 7.34 (t, J¼8.0 Hz, 2H, ArH), 7.09 (t,
114.22, 55.57, 24.24; HRMS [MþH]þ calcd for C9H11NO2 166.0868,
found 166.0870. Anal. Calcd for C9H11NO2 (165.08): C, 65.44; H,
6.71; N, 8.48. Found: C, 65.58; H, 6.62; N, 8.57.
J¼7.4 Hz,1H, ArH); 13C NMR (100 MHz, DMSO-d6)
¼164.79,138.95,
d
137.24, 134.29, 129.61, 128.62, 123.80, 120.38, 99.30; HRMS [MþH]þ
calcd for C13H10INO 323.9885, found 323.9882. Anal. Calcd for
C
13H10INO (322.98): C, 48.32; H, 3.12; N, 4.33. Found: C, 48.44; H,
4.2.23. N-o-Tolylacetamide (5p).11g White solid, mp 99e101 ꢀC;
3.02; N, 4.42.
yield: 73%% (ethyl acetate/petroleum ether: 1:4); 1H NMR
(400 MHz, CDCl3)
d
¼7.65 (d, J¼8.4 Hz,1H, ArH), 7.46 (s,1H, NH), 7.19
4.2.16. 3-Methyl-N-phenylbenzamide (5i).11a White solid, mp
125e126 ꢀC; yield: 81% (ethyl acetate/petroleum ether: 1:10); 1H
(t, J¼6.8 Hz, 2H, ArH), 7.09 (t, J¼7.2 Hz, 1H, ArH), 2.24 (s, 3H, CH3),
2.17 (s, 3H, CH3); 13C NMR (100 MHz, CDCl3)
d¼168.79, 135.61,
NMR (400 MHz, CDCl3)
d
¼7.89 (s, 1H, NH), 7.58 (t, J¼7.2 Hz, 4H, ArH),
130.50, 130.06, 126.62, 125.51, 123.94, 24.08, 17.84; HRMS [MþH]þ
calcd for C9H11NO 150.0919, found 150.0922. Anal. Calcd for
C9H11NO (149.08): C, 72.46; H, 7.43; N, 9.39. Found: C, 72.58; H,
7.32; N, 9.46.
7.29e7.25 (m, 4H, ArH), 7.06 (t, J¼7.4 Hz, 1H, ArH), 2.32 (s, 3H, CH3);
13C NMR (100 MHz, CDCl3)
d¼165.97, 138.60, 137.93, 134.88, 132.50,
129.00, 128.55, 127.75, 124.42, 123.92, 120.15, 21.34; HRMS [MþH]þ
calcdforC14H13NO212.1075, found212.1077. Anal. CalcdforC14H13NO
(211.10): C, 79.59; H, 6.20; N, 6.63. Found: C, 79.73; H, 6.11; N, 6.72.
4.2.24. N,2-Diphenylacetamide (5q). White solid, mp 115e116 ꢀC;
yield: 72% (ethyl acetate/petroleum ether: 1:4); 1H NMR (400 MHz,
4.2.17. N-Phenylacetamide (5j).11g White solid, mp 112e114 ꢀC;
CDCl3)
7.26e7.23 (m, 3H, ArH), 7.21e7.17 (m, 2H, ArH), 7.00 (t, J¼7.4 Hz, 1H,
ArH), 3.63 (s, 2H, CH2); 13C NMR (100 MHz, CDCl3)
d¼7.34 (d, J¼8.4 Hz, 2H, ArH), 7.29 (d, J¼7.2 Hz, 2H, ArH),
yield: 77% (ethyl acetate/petroleum ether: 1:5); 1H NMR (400 MHz,
CDCl3)
d
¼8.14 (s, 1H, NH), 7.44 (t, J¼4.4 Hz, 2H, ArH), 7.21 (t,
d¼169.18, 137.56,
J¼8.0 Hz, 2H, ArH), 7.01 (t, J¼7.4 Hz, 1H, ArH), 2.07 (s, 3H, CH3); 13
C
134.38, 129.44, 129.12, 128.86, 127.56, 124.38, 119.81, 44.69; HRMS
[MþH]þ calcd for C14H13NO 212.1075, found 212.1073. Anal. Calcd
for C14H13NO (211.10): C, 79.59; H, 6.20; N, 6.63. Found: C, 79.70; H,
6.11; N, 6.52.
NMR (100 MHz, CDCl3)
d
¼169.01, 137.90, 128.80, 124.21, 120.07,
24.31; HRMS [MþH]þ calcd for C8H9NO 136.0762, found 136.0760.
Anal. Calcd for C8H9NO (135.07): C, 71.09; H, 6.71; N, 10.36. Found:
C, 71.16; H, 6.58; N, 10.70.
4.2.25. 1-Phenylthiourea (5r). White solid, mp 150e152 ꢀC; yield:
4.2.18. N-(4-Fluorophenyl)acetamide
(5k). White
solid,
mp
45% (ethyl acetate/petroleum ether: 1:2); 1H NMR (400 MHz,
152e154 ꢀC; yield: 65% (ethyl acetate/petroleum ether: 1:2); 1H
DMSO-d6)
d
¼9.71 (s, 1H, NH), 7.58 (s, 2H, NH), 7.40 (t, J¼8.0 Hz, 2H,

Z.-J. Quan et al. / Tetrahedron 69 (2013) 8368e8374
8373
ArH), 7.34e7.30 (m, 2H, ArH), 7.13e7.09 (m, 2H, ArH); 13C NMR
Calcd for C14H13NO (211.10): C, 79.59; H, 6.20; N, 6.63. Found: C,
79.50; H, 6.10; N, 6.72.
(100 MHz, DMSO-d6)
d
¼180.93, 139.04, 128.77, 124.48, 123.10;
HRMS [MþH]þ calcd for C7H8N2S 153.0486, found 153.0488. Anal.
Calcd for C7H8N2S (160.10): C, 52.45; H, 10.06; N, 17.48. Found: C,
52.49; H, 9.98; N, 17.56.
4.3.2. N-Methyl-N-phenylbenzamide (8b). Red-brown oil; yield:
69% (ethyl acetate/petroleum ether: 1:7); 1H NMR (400 MHz,
CDCl3)
d
¼7.23e7.20 (m, 2H, ArH), 7.14e7.10 (m, 3H, ArH), 7.08e7.03
4.2.26. 4-Benzamido-N-phenylbenzamide (5s). White solid, mp
233e234 ꢀC; yield: 65% (ethyl acetate/petroleum ether: 1:2); 1H
(m, 3H, ArH), 6.95e6.93 (m, 2H, ArH), 3.41 (s, 3H, CH3); 13C NMR
(100 MHz, CDCl3)
d
¼170.46, 144.69, 135.71, 129.41, 128.96, 128.53,
NMR (400 MHz, DMSO-d6)
d
¼10.12 (s,1H, NH), 9.98 (s,1H, NH), 7.84
127.54, 126.71, 126.30, 38.22; HRMS [MþH]þ calcd for C14H13NO
212.1075, found 212.1073. Anal. Calcd for C14H13NO (211.10): C,
79.59; H, 6.20; N, 6.63. Found: C, 79.67; H, 5.99; N, 7.02.
(d, J¼8.8 Hz, 2H, ArH), 7.75 (t, J¼4.4 Hz, 2H, ArH), 7.43e7.29 (m, 7H,
ArH), 7.07e7.03 (m, 1H, ArH), 6.86 (d, J¼8.8 Hz, 2H, ArH); 13C NMR
(100 MHz, DMSO-d6)
d
¼165.11, 160.52, 139.45, 133.63, 129.91,
129.71, 128.53, 125.42, 123.28, 120.27, 114.91; HRMS [MþH]þ calcd
4.3.3. N-Methyl-N,2-diphenylacetamide (8c). White oil; yield: 65%
for
C
20H16N2O2 317.1290, found 317.1287. Anal. Calcd for
(ethyl acetate/petroleum ether: 1:3); 1H NMR (400 MHz, CDCl3)
C
20H16N2O2 (316.12): C, 75.93; H, 5.10; N, 8.86. Found: C, 76.00; H,
d
¼7.39e7.32 (m, 3H, ArH), 7.22e7.18 (m, 3H, ArH), 7.11 (d, J¼7.6 Hz,
5.03; N, 8.90.
2H, ArH), 7.05 (d, J¼6.8 Hz, 2H, ArH), 3.46 (s, 2H, CH2), 3.27 (s, 3H,
CH3); 13C NMR (100 MHz, CDCl3)
d¼170.86, 143.81, 135.30, 129.57,
4.2.27. 4-Acetamido-N-phenylbenzamide (5t). White solid, mp
227e229 ꢀC; yield: 63% (ethyl acetate/petroleum ether: 1:1); 1H
128.91, 128.17, 127.81, 127.48, 126.42, 40.77, 37.47; HRMS [MþH]þ
calcd for C15H15NO 226.1232, found 226.1234. Anal. Calcd for
NMR (400 MHz, DMSO-d6)
d
¼10.23 (s, 1H, NH), 10.12 (s, 1H, NH),
C15H15NO (225.12): C, 79.97; H, 6.71; N, 6.22. Found: C, 79.99; H,
6.63; N, 6.30.
7.92 (d, J¼8.8 Hz, 2H, ArH), 7.77e7.71 (m, 4H, ArH), 7.33 (t, J¼8.0 Hz,
2H, ArH), 7.09e7.05 (m, 1H, ArH), 2.08 (s, 3H, CH3); 13C NMR
(100 MHz, DMSO-d6)
d
¼168.81, 164.96, 142.28, 139.30, 129.06,
4.3.4. 1-Phenylazepan-2-one (8d). White solid, mp 71e72 ꢀC; yield:
128.63, 128.59, 123.50, 120.35, 118.13, 24.17; HRMS [MþH]þ calcd
61% (ethyl acetate/petroleum ether: 1:3); 1H NMR (400 MHz,
for
C15H14N2O2 255.1134, found 255.1137. Anal. Calcd for
CDCl3)
d
¼7.38e7.34 (m, 2H, ArH), 7.23e7.20 (m, 3H, ArH), 3.74 (d,
C
15H14N2O2 (254.11): C, 70.85; H, 5.55; N, 11.02. Found: C, 70.94; H,
J¼4.0 Hz, 2H, CH2), 2.70 (s, 2H, CH2), 1.81 (s, 4H, CH2), 1.23 (s, 2H,
5.45; N, 11.09.
CH2); 13C NMR (100 MHz, CDCl3)
d¼175.48, 144.48, 129.01, 126.33,
126.17, 52.96, 37.63, 29.80, 28.84, 23.49; HRMS [MþH]þ calcd for
4.2.28. 4-Amino-N-phenylbenzamide
(6a). White solid,
mp
C12H15NO 190.1232, found 190.1235. Anal. Calcd for C12H15NO
140e141 ꢀC; yield: 60% (ethyl acetate/petroleum ether: 1:2); 1H
(189.12): C, 76.16; H, 7.99; N, 7.40. Found: C, 76.27; H, 7.95; N, 7.48.
NMR (400 MHz, DMSO-d6)
d
¼9.18 (s, 1H, NH), 7.17e7.13 (m, 4H,
ArH), 6.72 (t, J¼8.0 Hz, 2H, ArH), 6.47e6.43 (m, 1H, ArH), 6.02 (d,
Acknowledgements
J¼8.8 Hz, 2H, ArH), 5.18 (s, 2H, NH2); 13C NMR (100 MHz, DMSO-d6)
d
¼165.32, 152.15, 139.78, 129.37, 128.47, 122.91, 121.09, 120.13,
We are thankful for the financial support from the National
Nature Science Foundation of China (Nos. 20902073 and 21062017),
the Natural Science Foundation of Gansu Province (No.
1208RJYA083), and the Scientific and Technological Innovation
Engineering program of Northwest Normal University (Nos.
nwnukjcxgc-03-64, nwnulkqn-10-15).
112.56; HRMS [MþH]þ calcd for C13H12N2O 213.1022, found
213.1024. Anal. Calcd for C13H12N2O (212.10): C, 73.56; H, 5.70; N,
13.20. Found: C, 73.47; H, 5.60; N, 13.29.
4.2.29. 4-Amino-N-m-tolylbenzamide (6b). White solid, mp
128e130 ꢀC; yield: 57% (ethyl acetate/petroleum ether: 1:2); 1H
NMR (400 MHz, DMSO-d6)
d
¼9.72 (d, J¼1.6 Hz, 1H, NH), 7.76e7.73
(m, 2H, ArH), 7.58 (t, J¼12.6 Hz, 2H, ArH), 7.19 (t, J¼7.8 Hz, 1H, ArH),
6.86 (d, J¼8.0 Hz, 1H, ArH), 6.64e6.61 (m, 2H, ArH), 5.77 (s, 2H,
References and notes
NH2), 2.29 (s, 3H, CH3); 13C NMR (100 MHz, DMSO-d6)
d
¼165.30,
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4.3. General procedure for the synthesis of tertiary amides 8
The mixture of aryl iodides (1 mmol), secondary amides
(1.2 mmol), CuTC (0.15 mmol), and t-BuONa (2.0 mmol) in DMSO
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d
¼7.34e7.19 (m, 8H, ArH), 2.07 (s, 3H, CH3); 13C NMR
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