Reactions of aminopyrimidine derivatives with chloroacetyl and isophthaloyl chlorides

Article abstract of DOI:10.1002/hc.21458

1-Aminopyrimidine-2-one derivatives (1a-c) were prepared in two steps from furan-2,3-diones and semicarbazones in toluene/benzene. Pyrimidin-[1(2H)-yl] acetamide derivatives and isophthalimide derivatives were synthesized from the nucleophilic acyl substi

Full text of DOI:10.1002/hc.21458

Received: 5 March 2018
DOI: 10.1002/hc.21458
Revised: 27 October 2018
Accepted: 2 November 2018
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|
R E S E A R C H A R T I C L E
Reactions of aminopyrimidine derivatives with chloroacetyl and
isophthaloyl chlorides
Zeynep Çimen1
Senem Akkoç2
Zülbiye Kökbudak2
|
|
1Polatli Faculty of Arts and Sciences
Ankara Hacı Bayram Veli University,
Polatli
2Department of Chemistry, Faculty of
Sciences, Erciyes University, Kayseri,
Turkey
Abstract
1-Aminopyrimidine-2-one derivatives (1a-c) were prepared in two steps from furan-
2,3-diones and semicarbazones in toluene/benzene. Pyrimidin-[1(2H)-yl] acetamide
derivatives and isophthalimide derivatives were synthesized from the nucleophilic
acyl substitution reactions of compounds 1a-c with chloroacetyl chloride. The struc-
1
13
Correspondence
tures of compounds 2a-f were verified by IR, H NMR, C NMR and elemental
analyses. The obtained final organic compounds were tested as catalysts in the
Mizoroki-Heck coupling reaction. They mostly exhibited very high catalytic activity
results for the coupling reaction of styrene with different aryl bromide derivatives.
Senem Akkoç, Department of Chemistry,
Faculty of Sciences, Erciyes University,
Kayseri, Turkey.
Email: senemakkoc44@gmail.com
Funding information
Erciyes University, Grant/Award Number:
FBY-12-4048
1
|
INTRODUCTION
ylacetophenonsemicarbazone and acetophenonsemicarbazone
[13]
with furan-2,3-dione derivatives, with chloroacetyl chloride
and isophthaloyl chloride. The newly developed compounds
(2a-f) were tested as catalysts in the Mizoroki-Heck reaction,
which is very important due to it has been used in different re-
search areas such as drug intermediates, fine chemicals synthe-
Pyrimidine and its derivatives are known as heterocyclic
compounds, and they show various important biological and
[
1]
pharmacological activities, such as antibacterial, antioxi-
[
2]
[3]
[4]
dant, antiviral, and anticancer. Due to their activity, the
syntheses of many significant pyrimidine derivatives have
[14]
ses, natural products, and industrial applications. According
to the results, tested compounds are very effective as catalysts
in carbon-carbon coupling reaction.
[5]
been reported by different researchers. However, there are
not many reports on the catalytic activity of pyrimidine de-
rivatives in the Mizoroki-Heck reaction. Amides and their
heterocyclic derivatives have also attracted great interest in
various branches of medicinal chemistry because of their
multiplicity of uses in the drug industry. Their pharmaceutical
2
EXPERIMENTAL
|
[6]
[7]
activities include insulin releasing, anti-inflammatory,
All necessary solvents and chemicals were commercially
purchased from Merck, Sigma-Aldrich, or Scharlau. The
synthesized compounds were checked for their homoge-
neity by using TLC. Microanalyses were performed on
a Carlo Erba Elemental Analyzer, Model 1108. Using an
ATR diamond device, the infrared (IR) spectra were re-
[
8]
[9]
antifungal, and carbonic anhydrase properties.
In our previous studies, the reactions of 1-aminopyrimidine-
[10]
[11]
2-one derivatives (1a-c) with anhydrides,
isocyanates,
[12]
and 1,3-dicarbonyl compounds were reported. In this study,
we aimed at the successful synthesis of six new pyrimidine
derivatives (2a-f) to make notable contributions to the class
of heterocyclic compounds. The new series of acetamide and
isophthalimide derivatives 2a-f were prepared from the reac-
tions of compounds 1a-c, which were obtained from 4-meth
−
1
corded in the range of 4000-600 cm . The NMR spectra
1
13
were recorded at 400 (for H NMR) and 100 MHz (for
C
NMR). The chemical shifts are given in δ (ppm). Using
an Agilent 6890N network GC System with a HP-5 col-
umn with a 30 m long column, 0.32 mm column diameter,
Contract grant sponsor: Erciyes Üniversitesi.
Contract grant number: FBY-12-4048.
Heteroatom Chemistry. 2018;e21458.
https://doi.org/10.1002/hc.21458
wileyonlinelibrary.com/journal/hc
© 2018 Wiley Periodicals, Inc.
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1 of 6

2
of 6
ÇIMEN Et al.
|
O
O
R
R
O
O
N
Ar
R
R
Ar
N
+
N NH
NH2
Ar
O
Ar
N
O
O
+
H , H O
2
a: Ar=C H , b: Ar=4-CH C H , c: Ar= 4-CH OC H
6
5
3
6
5
3
6
4
O
NH2
N
Ar
Ar
N
O
SCHEME 1 General reaction of
-aminopyrimidine-2-one derivatives (1a-c)
(1a-c)
1
O
O
NH2
O
Cl
NH
Ar
N
Ar
N
Cl
Cl
+
O
-HCl
Ar
N
O
Ar
N
O
(
1a-c)
a: Ar=C H , b: Ar=4-CH C H , c: Ar= 4-CH OC H
4
(
2a-c)
SCHEME 2 General reaction of
acetamide derivatives (2a-c)
6
5
3
6
5
3
6
and temperature range from −60 to 325°C, gas chromato-
graphic analysis was conducted.
2
5
.2.1
2-Chloro-N-[2-oxo-4-phenyl-
|
-(phenylcarbonyl)pyrimidin-1(2H)-yl]
acetamide, 2a
2
.1
Preparation of 1-aminopyrimidine-2-
|
Compound 2a was prepared as a colorless solid from com-
pound 1a and chloroacetyl chloride. Yield: 85%; m.p.: 198-
200°C. FT-IR: 3120 (-NH); 3058 and 2964 (C-H); 1718
and 1650 (C=O); 1614, 1515 and 1475 (C···C C···N); 800-
770 cm (pyrimidine ring). H NMR (400 MHz, CDCl3): δ
(ppm) = 10.64 (s, 1 H, CONH), 8.13 (s, 1 H, CH), 7.77-7.24
one derivatives, 1a-c
The compounds 1a-c were obtained from 4-methylacetop
henonsemicarbazone and acetophenonsemicarbazone with
[
13]
−1
1
furan-2,3-dione derivatives (Scheme 1).
We carried
out the reactions of 1a-c with chloroacetyl chloride and
isophthaloyl chloride in this study. Thus, the new series of
amide and isophthalimide derivatives (2a-f) were synthe-
sized. The general outlines of the reactions are shown in
Schemes 2 and 3.
1
3
(m, 10 H, Ar-H), 4.32 (s, 2 H, CH2). C NMR (100 MHz,
CDCl3): δ (ppm) = 190.65, 174.11 and 166.59 (Ph-C=O,
NH-C=O and C=O), 152.25, 151.91, 136.09, 135.69, 133.86,
131.82, 129.86, 129.23, 129.03, 128.78, 128.47, 117.37 (ar-
omatic C), 41.02 (CH ). Anal. Cald. for C H ClN O : C,
2
19 14
3
3
6
2.05; H, 3.84; N, 11.43. Found: C, 62.14; H, 3.84; N, 11.43.
2
.2
General procedure for the synthesis of
|
acetamide derivatives, 2a-c
2
.2.2
2-Chloro-N-[4-(4-methylphenyl)-5-
|
To a solution of the 1-aminopyrimidine-2-one derivatives
[
(4-methylphenyl)carbonyl]-2-oxo-1(2H)-yl]
(
1a-c) (0.28 or 0.34 mmol) in acetonitrile (15 mL), chlo-
acetamide, 2b
roacetyl chloride (1.25 mmol) was added. The mixture was
stirred by a magnetic stirrer at 0°C for 3-6 hours. The reac-
tion mixture was evaporated to dryness to obtain the corre-
sponding acetamide derivatives (2a-c). Then, the residue was
treated with dry diethyl ether and filtered. The crude product
was recrystallized from ethyl alcohol (EtOH) and allowed to
dry on phosphorus pentoxide (P O )
Compound 2b was prepared as a colorless solid from com-
pound 1b and chloroacetyl chloride. Yield: 83%; m.p.: 218-
220°C. FT-IR: 3168 (-NH); 3035 (aromatic C-H); 2933
(aliphatic C-H); 1712, 1668 and 1647 (carbonyl’s C=O);
1587 and 1504 (C···C C···N); 800-770 cm (pyrimidine
ring). H NMR (400 MHz, CDCl3): δ (ppm) = 10.52 (s, 1
−
1
1
2
5 .

ÇIMEN Et al.
3 of 6
|
O
Ar
O
Cl
O
N
O
N
NH2
O
O
Ar
N
NH
O
HN
O
+
Ar
Ar
Ar
N
O
-
2HCl
O
(
1a-c)
Ar
N
N
Cl
a: Ar=C H , b: Ar=4-CH C H , c: Ar= 4-CH OC H
4
(2d-f)
6
5
3
6
5
3
6
SCHEME 3 General reaction of isophthalimide derivatives (2d-f)
H, CONH), 8.04 (s, 1 H, CH), 7.74-7.08 (m, 8 H, Ar-H),
1
3
2
.3.1
N ,N -bis(5-benzoyl-2-oxo-4-
1
3
|
4
.31 (s, 2 H, CH ), 2.39 and 2.31 (s, 6 H, 2CH ). C NMR
2
3
phenylpyrimidin-1(2H))-isophthalimide, 2d
(
(
100 MHz, CDCl ): δ (ppm) = 190.39, 173.81 and 170.89
3
Ph-C=O, NH-C=O and C=O), 166.45, 152.16, 150.93,
Compound 2d was prepared as a colorless solid from compound
1a and isophthaloyl chloride. Yield: 59%; m.p.: 186-188°C. FT-
IR: 3190 (-NH); 3058 (aromatic C-H); 2977 (aliphatic C-H);
1643 (carbonyl’s C=O); 1587 and 1471 (C···C C···N); 800-
1
1
45.14, 142.72, 133.55, 132.79, 130.14, 129.58, 129.44,
29.22 (aromatic C), 41.02 (CH ), 21.74 and 21.52 (2CH ).
2
3
Anal. Cald. for C H ClN O : C, 63.72; H, 4.58; N, 10.62.
Found: C, 63.54; H, 4.53; N, 10.43.
2
1
18
3
3
−
1
1
770 cm (pyrimidine ring). H NMR (400 MHz, CDCl3):
δ (ppm) = 11.82 (s, 2 H, CONH), 8.61-7.23 (m, 26 H, ArH).
13
C NMR (100 MHz, CDCl ): δ (ppm) = 190.69, 174.60 and
3
2
.2.3
(4-methoxyphenyl)carbonyl]-2-oxopyrimidin-
(2H)-yl]acetamide, 2c
2-Chloro-N-[4-(4-methoxyphenyl)-5-
|
1
1
1
64.56 (Ph-C=O, NH-C=O, and C=O), 158.53, 154.10, 153.47,
36.11, 133.72, 132.28, 131.66, 129.94, 129.28, 128.73, 128.33,
18.02 (aromatic C). Anal. Cald. for C H N O : C, 70.78; H,
[
1
42 28 6 6
Compound 2c was prepared as a colorless solid from com-
3.96; N, 11.79. Found: C, 71.01; H, 4.15; N, 11.95.
pound 1c and chloroacetyl chloride. Yield: 86%; m.p.: 188-
1
90°C. FT-IR: 3168 (-NH); 3035 (aromatic C-H); 2933
1
3
2
.3.2
N ,N -bis(5-(4-methylbenzoyl)-2-oxo-
|
(
aliphatic C-H); 1712, 1668, and 1647 (carbonyl’s C=O);
4
-p-tolypyrimidin-1(2H)-yl)isophthalimide, 2e
−1
1
587 and 1504 (C···C C···N); 800-770 cm (pyrimidine
1
ring). H NMR (400 MHz, CDCl ): δ (ppm) = 10.70 (s, 1 H,
Compound 2e was prepared as a colorless solid from com-
pound 1b and isophthaloyl chloride. Yield: 64%; m.p.: 187-
189°C. FT-IR: 3138 (-NH); 3030 (aromatic C-H); 2912
(aliphatic C-H); 1650 (carbonyl’s C=O); 1598 and 1471
3
CONH), 8.00 (s, 1 H, CH), 7.82-6.76 (m, 8 H, Ar-H), 4.32 (s,
1
3
2
-H, CH ), 3.85-3.78 (s, 6 H, OCH ). C NMR (100 MHz,
2
3
CDCl ): δ (ppm) = 189.75, 172.05, and 166.50 (Ph-C=O,
3
−
1
1
NH-C=O, and C=O), 164.29, 162.87, 152.36, 150.71,
(C···C C···N); 800-770 cm (pyrimidine ring). H NMR
(400 MHz, CDCl3): δ (ppm) = 11.90 (s, 2 H, CONH), 8.63-
1
32.48, 131.77, 131.63, 128.92, 127.75, 114.19, 113.97 (aro-
1
3
matic C), 55.60 and 55.39 (OCH ), 41.02 (CH ). Anal. Cald.
7.04 (m, 22 H, ArH), 2.41-2.29 (s, 12 H, 2CH3). C NMR
(100 MHz, CDCl3): δ (ppm) = 190.46, 174.36 and 164.52
(Ph-C=O, NH-C=O and C=O), 154.16, 152.80, 144.91,
3
2
for C H ClN O : C, 58.95; H, 4.24; N, 9.82. Found: C,
2
1
18
3
5
5
9.15; H, 4.19; N, 9.63.
1
1
42.37, 133.57, 133.11, 132.17, 130.19, 129.51, 129.46,
29.07 (aromatic C), 21.71 and 21.49 (2CH ). Anal. Cald. for
3
2
.3
General procedure for the synthesis of
|
C H N O : C, 71.86; H, 4.72; N, 10.93. Found: C, 72.02;
4
6
36
6
6
isophthalimide derivatives, 2d-f
H, 4.81; N, 11.01.
To a solution of the compounds (1a-c) (0.94-1.10 mmol) in
acetonitrile (30 mL), isophthaloyl chloride (0.44-0.59 mmol)
was added. After the reaction mixture was stirred at room
temperature for 7 hours, the mixture was evaporated. Then,
the residue was treated with dry diethyl ether. The precipitate
was filtered and recrystallized from butyl alcohol (BuOH)
and allowed to dry on P O .
1
3
2
.3.3
N ,N -bis(5-(4-methoxybenzoyl)-4-
|
(
4-methoxyphenyl)-2-oxopyrimidin-1(2H)-yl)
isophthalimide, 2f
Compound 2f was prepared as a colorless solid from com-
pound 1c and isophthaloyl chloride. Yield: 63%; m.p.:
2
5

4
of 6
ÇIMEN Et al.
|
TABLE 1 Mizoroki-Heck coupling reaction in the presence of the in situ generated catalysts from different organic compoundsa,b
Pd(OAc)
2
(1.0 mmol % )
2
a-f (2.0 mmol %)
R
R
Br
+
K CO , DMF/H O
2
3
2
Entry
R
LHX
2c
Time
Temp.
Product
Yield (%)
1
COCH3
2
80
94
COCH3
2
3
4
5
OCH3
OCH3
OCH3
OCH3
2a
2a
2a
2a
18
18
18
2 h
60
80
100
80
89
93
96
86
OCH
3
6
7
8
9
OCH3
OCH3
H(Cl)
H(Br)
H (I)
2a
2a
2b
2c
2d
1
24
2
2
2
80
80
80
80
80
80
96
96
99
100
1
0
CH3
11
12
13
14
H (I)
H (I)
NO2
NO2
2e
2f
2b
2c
2
2
2
2
80
80
80
80
100
100
4
93
NO
2
15
16
17
NO2
NO2
NO2
2d
2e
2f
2
2
2
80
80
80
1
1
13.9
a
Reaction conditions: styrene (1.5 mmol), p-R-C H Br (1.0 mmol), Pd(OAc) (1.0 mmol%), 2a-f (2.0 mmol%), K CO (2.0 mmol), DMF-H O (2-2 mL), 80°C, 2 h.
6
4
2
2
3
2
b
Yields were determined by GC.
-
.
.
:
O
:
.
.
O
O
.
.
:
H
N
H
O
Cl
NH
Ar
Ar
2
N
N
Cl
:
:
Cl
..
Cl
Ar
N
O
Ar
N
O
1
a-c
-
-
Cl
O
O
O
O
H
N
H
Ar
Cl
Ar
Cl
N
N
N
H
O
-
-HCl
Ar
N
O
-
Cl
Ar
N
SCHEME 4 General mechanism of
compounds (2a-c)
a: Ar; C H -, b: Ar; 4-CH C H -, c: Ar; 4-CH O-C H -
2
a-c
6
5
3-
6
4
3
6 4

ÇIMEN Et al.
5 of 6
|
1
96-198°C. FT-IR: 3153 (-NH); 3066 (aromatic C-H); 2916
K CO at 80°C for different times. In the coupling reac-
2
3
(
aliphatic C-H); 1660 (carbonyl’s C=O); 1550 and 1467
tion of styrene with aryl bromides, the in situ formed com-
plexes mostly exhibited high yields as catalysts (Table 1,
entries 1-12). However, they (except for 2c) displayed
very low activity when the electron-withdrawing group
(1-bromo-4-nitrobenzene) was used as a coupling partner
with styrene (Table 1, entries 13, 15-17).
−
1
1
(
C···C C···N); 800-770 cm (pyrimidine ring). H NMR
(
400 MHz, CDCl ): δ (ppm) = 12.32 (s, 2 H, CONH), 8.69-
3
1
3
6
.93 (m, 22 H, Ar-H), 3.83-3.76 (s, 12 H, 2OCH ). C NMR
3
(
(
100 MHz, CDCl ): δ (ppm) = 189.60, 173.03, and 164.64
3
Ph-C=O, NH-C=O and C=O), 164.12, 162.66, 154.23,
1
1
52.34, 132.48, 131.64, 130.26, 129.29, 128.96, 128.09,
14.08, 113.80 (aromatic C), 55.53 and 55.34 (2CH ). Anal.
In the presence of compound 2a, the coupling reaction
of 4-bromoanisole with styrene was conducted at three dif-
ferent temperatures (60, 80, and 100°C) (Table 1, entries
2-4). The coupling product was obtained in very high yield
at 100°C (Table 1, entry 4). However, there is not a signifi-
cant difference with that at 80°C. Therefore, we conducted
the other reaction at 80°C. When the time was screened,
we observed there is not a big difference between 2 and
24 hours for this reaction under the determined reaction
conditions (Table 1, entries 5 and 7). In the coupling reac-
tion of 4-bromotoluene with styrene, the coupling product
was achieved in excellent yields like 96%-100% (Table 1,
entries 8-12).
3
Cald. for C H N O : C, 66.34; H, 4.36; N, 10.09. Found:
4
6
36
6
10
C, 66.61; H, 4.57; N, 10.29.
2
.4
General procedure for the Mizoroki-
|
Heck coupling reaction
Compounds 2a-f (2.0 mmol%) as catalyst, styrene
(
1.5 mmol), Pd(OAc) (1.0 mmol), aryl bromide (1.0 mmol),
2
K CO (2.0 mmol), and H O-DMF (2-2 mL) were added
2
3
2
to a small Schlenk tube (25 mL). The reaction mixture was
heated to 80°C for 2 hours. Then, the mixture was extracted
[
14c]
with ethyl acetate.
4
CONCLUSIONS
|
3
RESULTS AND DISCUSSION
|
In the present study, new organic compounds were synthe-
sized, and their structures were characterized by elemental
The N-aminopyrimidine derivatives (1a-c) were prepared as
shown in Scheme 1. The new pyrimidin-[1-(2H)-yl]aceta-
mide (2a-c) and isophthalimide derivatives (2d-f) were pre-
pared in moderate yields (59%-86%) from the reactions of
chloroacetyl chloride and isophthaloyl chloride with 1a-c
1
13
analysis, FT-IR, H and C NMR. The catalytic activity of
compounds was tested in the Mizoroki-Heck coupling reac-
tion. They generally showed high results for coupling sty-
rene with various aryl bromides (4-bromoacetophenone,
4-bromoanisole, and 4-bromotoluene). However, they exhib-
ited very low activity when the electron-withdrawing group
(1-bromo-4-nitrobenzene) was used as a coupling partner
with styrene.
1
compounds. The structures of 2a-f were verified by IR, H
1
3
NMR, C NMR, and elemental analysis. The details of the
reaction pathway of 1a-c with chloroacetyl chloride and
isophthaloyl chloride as outlined are given in Schemes 2 and
3
.
The compound 2a was obtained in 85% yield by treating
ACKNOWLEDGMENTS
chloroacetyl chloride with compound 1a in 15 mL acetoni-
trile at 0°C for 4 hours. In the IR spectrum of compound 2a,
This study was financially supported by Erciyes University
Research Fund (FBY-12-4048).
−
1
the N-H absorption band is found to be at about 3120 cm .
The C=O absorption bands are found to be at 1718 and
−1
1
650 cm . The multiple peaks between 7.77 and 7.24 ppm
1
CONFLICT OF INTEREST
are thought to represent the aromatic protons in the H NMR
1
3
spectra. The peak at 10.64 ppm represents the -NH. In the C
The authors have no conflict of interest to declare.
NMR spectrum of compound 2a, the peaks corresponding to
1
90.65, 174.11, 166.59 and 41.02 ppm indicate the presence
ORCID
of carbonyl (C=O) and methylene (CH ) groups.
2
The general mechanism of products 2a-c is given in
Scheme 4. Furthermore, the mechanism of compounds 2d-e
is very similar to it.
Senem Akkoç
http://orcid.org/0000-0001-8913-757X
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How to cite this article: Çimen Z, Akkoç S,
Kökbudak Z. Reactions of aminopyrimidine
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