Supporting Material

Nano-TiCl4/SiO2: An efficient catalyst for the one-pot synthesis of highly

substituted dihydro-2-oxypyrroles

Abdolhamid Bamoniri · Bi Bi Fatemeh Mirjalili · Reza Tarazian

CONTENTS

Materials and instruments 2

Experimental procedure 2

Characterization of the nano-TiCl4/SiO2 3

Characterization data for compounds 6

A. Bamoniri · R. Tarazian Department of Organic Chemistry, Faculty of Chemistry, University of Kashan, Kashan, I. R Iran Corresponding author e-mail: bamoniri@kashanu.ac.ir Tel: +98 31 55912384; Fax: +98 31 55912397; P. O. Box: 87317-51167 B. B. F. Mirjalili Department of Chemistry, College of Science, Yazd University, Yazd, I. R. Iran

2

Materials and instruments

All chemicals and solvents were purchased from the Merck and Fluka Chemical Companies in high purity.

Materials were used from the commercial reagent grade. FT-IR spectra were recorded as KBr pellet on a

Bruker, Eqinox 55 spectrometer Perkin-Elmer 781 spectrophotometer. 1H NMR, 13C NMR, H-H COSY

and C-H COSY (HSQC) spectra were recorded at 400 MHz for 1H and 100 MHz for 13C on a Bruker

DXR-400 spectrometer using CDCl3 and DMSO as solvent and tetramethylsilane as internal standard.

Mass spectra (MS) were recorded on a FINNIGAN-MAT 8430 mass spectrometer, operating at an

ionization potential of 70 eV. Elemental analysis C.H.N. was performed using a Vario EL analyzer. The X-

ray diffraction (XRD) patterns of nano-TiCl4/SiO2 was recorded by employing a Philips Xpert MPD

diffractometer equipped with a Cu Kα anode (λ = 1.54 A°) in the 2θ range from 10 to 80°. The SEM

and TEM of nano-TiCl4/SiO2 were determined with a VEGA/TESCAN scanning electron microscope and

LEO912AB-OMEGA transmission electron microscopy, respectively. The thermal gravimetric analysis

(TGA) was done with “NETZSCH TG 209 F1 Iris” instrument. Melting points were obtained with a

Yanagimoto micro melting point apparatus. The purity determination of the substrates and reactions

monitoring were accomplished by TLC on silica gel polygram SILG/UV 254 plates.

Experimental procedure

Preparation of 50% TiCl4/SiO2 and 50% nano-TiCl4/SiO2

In a well-ventilated system, TiCl4 (1.2 cm3) was added dropwise to the mixture of silica

gel (0.5 g) or nano silica gel (0.5 g) in chloroform (5 cm3). The mixture was stirred for one

hour at room temperature. The resulted suspension was filtered, washed with chloroform and

dried at room temperature.

3

Typical procedure for synthesis of dihydro-2-oxopyrroles

In a round-bottom flask equipped with a reflux condenser (50 cm3), firstly, a mixture of

substituted anilines 1a-g (2 mmol) and dialkylacetylenedicarboxylate 2a, 2b (1 mmol) in

absolute ethanol (3 mL) was stirred for 15 min. Then, formaldehyde 37% in methanol 3 (3

mmol) and nano-TiCl4/SiO2 (0.08 g) were added successively and the mixture was heated at

70 oC for appropriate time (table 2). The progress of the reaction was monitored by TLC.

After completion of the reaction, the mixture was allowed to be cooled. Then, the mixture

was filtered off, washed with EtOH (3×10 mL) and dried. Chloroform (15 mL) was added to

remove the catalyst. The solvent was evaporated in air. The crude product was recrystallized

from ethanol to give the corresponding dihydro-2-oxopyrroles 4a-m in high yields with high

purification. The products were identified by physical and spectroscopic data.

Characterization of the nano-TiCl4/SiO2

In the FT-IR spectrum of the catalyst shows the fundamental asymmetric stretching

absorption band of Ti-O-Si at 932 cm-1 as TiCl4 supported on nano-SiO2. The absorption band

of Ti–Cl occurs at 1626 cm-1. The absorption bands Si–OH and Si–O–Si appear about 800

and 1100 cm-1, respectively [39,40] (Fig. 1). Powder X-ray diffraction (XRD) of nano-

TiCl4.SiO2 was run and the position of all peaks was characterized. XRD pattern of nano-

TiCl4.SiO2 is shown in Fig. 2. According to Scherrer equation [41], the broadening of peaks

alludes to decrease in crystalline size of nano-TiCl4.SiO2. The strongest peak of the XRD

pattern is corresponded to the nano SiO2 plane in 2θ=22o. The other peaks indexed in 2θ

values of 27o, 36o, 41o, 54o, 62o and 69o are related planes of supported titanium tetrachloride

(Fig. 2). The morphology of the catalyst particles was investigated by SEM and TEM. SEM

4

and TEM images of nano-TiCl4.SiO2 are shown in Fig. 3. The particle size in TEM pattern

was evaluated between 14-20 nm by GetData Graph program. Thermal stability of nano-

TiCl4/SiO2 was surveyed by TGA analysis (Fig. 4). TGA pattern of the catalyst was obtained

in the range of 23.43 to 513.43 °C. The catalyst is stable to 173.43 °C and only 2.98% of its

weight was decreased in 173.43°C. This initial reduced mass (2.98%) of catalyst related to

removal of catalyst moisture. From 173.43oC to 513.43°C, the weight loss of the catalyst is

2.15%. Only 5.13% of the catalyst weight was reduced between 23.43 to 513.43°C. The

proposed structure for nano-TiCl4/SiO2 is shown at Fig. 5. As showed in Fig. 5 nano-

TiCl4/SiO2 can act as Lewis acid catalyst.

Fig. 1 FT-IR spectrum of nano-TiCl4/SiO2

Fig. 2 XRD pattern of nano-TiCl4/SiO2

%Tr

ansm

ittan

ce

wavenumbers (cm-1)

5

Fig. 3 SEM (a) and TEM (b) images of nano-TiCl4/SiO2

Fig. 4 TGA pattern of nano-TiCl4/SiO2

Fig.5 Proposed structure of harbored nanosilica supported titanium tetrachloride

6

Characterization Data for Compounds

Methyl-5-oxo-1-(p-tolyl)-4-(p-tolylamino)-2,5-dihydro-1H-pyrrole-3-carboxylate (4a, C22H26N2O3).

Pale yellow solid. m.p.: 175-176 °C (Ref. [32] 175-176 °C). 1H NMR (400 MHz, CDCl3): δ= 8.00 (br, s,

1H, NH), 7.66 (br, s, 2H, Ar–H), 7.19 (br, s, 2H, Ar–H), 7.12 (br, s, 2H, Ar–H), 7.04 (br, s, 2H, Ar–H), 4.50

(s, 2H, NCH2), 3.75 (s, 3H, OCH3), 2.34 (s, 6H, Ar-Me) ppm; 13C NMR (100 MHz, CDCl3): δ =164.9,

163.5, 143.5, 136.2, 135.9, 134.7, 134.4, 129.6 (2C), 128.9 (2C), 123.1 (2C), 119.2 (2C), 101.8, 51.2, 48.2,

21.0, 20.8; FT-IR (KBr): ῡ = 3287, 1679, 1648, 1517, 1442, 1398, 1225, 1151 cm-1. Anal. Calcd for

C22H26N2O3: C, 71.41; H, 5.99; N, 8.33; O, 14.27. Found: C, 70.85; H, 5.32; N, 8.18; O, 14.16.

The FT-IR spectrum of product (4a)

7

The 1H NMR (400MHz) spectrum of product (4a)

The 13C NMR (100MHz) spectrum of product (4a)

8

Ethyl-5-oxo-1-(p-tolyl)-4-(p-tolylamino)-2,5-dihydro-1H-pyrrole-3-carboxylate (4b, C21H22N2O3)

Cream solid. m.p.: 128 °C (Ref. [29] 131-132 °C). 1H NMR (400 MHz, CDCl3): δ= 7.98 (br, s, 2H, NH),

7.67 (d, 2H, 3J = 8.4 Hz, Ar–H), 7.19 (d, 2H, 3J = 8.0 Hz, Ar–H), 7.11 (d, 2H, 3J = 8.0 Hz, Ar–H), 7.04 (d,

2H, 3J = 8.4 Hz, Ar–H), 4.51 (s, 2H, NCH2), 4.21 (q, 2H, 3J = 7.2 Hz, OCH2), 2.34 (d, 6H, 3J = 2.8 Hz, Ar-

Me), 1.22 (t, 3H, 3J = 7.2 Hz, OCH2CH3) ppm; FT-IR (KBr): ῡ =3289, 1695, 1642, 1514, 1398, 1299,

1172, 1105, 1041 cm-1. Anal. Calcd for C21H22N2O3: C, 71.98; H, 6.33; N, 7.99; O, 13.70. Found: C, 70.90;

H, 6.12; N, 7. 23; O, 13.33.

The FT-IR spectrum of product (4b)

9

The 1H NMR (400MHz) spectrum of product (4b)

Methyl1-(4-ethylphenyl)-4-((4-ethylphenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4c,

C22H24N2O3)

Cream solid. m.p.: 124 °C. 1H NMR (400 MHz, CDCl3): δ= 8.03 (br, s, 1H, NH), 7.69 (br, s, 2H, Ar–H),

7.22 (br, s, 2H, Ar–H), 7.14 (br, s, 2H, Ar–H), 7.07 (br, s, 2H, Ar–H), 4.51 (s, 2H, NCH2), 3.73 (s, 3H,

OCH3), 2.65 (s, 4H, Ar-CH2CH3), 1.24 (t, 3J = 5.2 Hz, 6H, Ar-CH2CH3) ppm; FT-IR (KBr): ῡ = 3287,

1679, 1644, 1609, 1519, 1438, 1403, 1371, 1303, 1274, 1222, 1149, 834 cm-1.

`

10

The FT-IR spectrum of product (4c)

The 1H NMR (400MHz) spectrum of product (4c)

11

Ethyl1-(4-ethylphenyl)-4-((4-ethylphenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4d,

C23H26N2O3)

Cream solid. m.p.: 98-100 °C. 1H NMR (400 MHz, CDCl3): δ= 7.97 (br, s, 2H, NH), 7.67 (d, 2H, 3J = 8.0

Hz, Ar–H), 7.19 (d, 2H, 3J = 8.0 Hz, Ar–H), 7.12 (d, 2H, 3J = 8.0 Hz, Ar–H), 7.05 (br, s, 2H, Ar–H), 4.50

(s, 2H, NCH2), 4.19 (br, s,, 2H, OCH2), 2.63 (br, s, 4H, Ar-CH2CH3), 1.56 (br, s, 3H, OCH2CH3), 1.21 (br,

s, 6H, Ar-CH2CH3) ppm; 13C NMR (100 MHz, CDCl3): δ =164.7, 163.8, 143.1, 141.2, 140.6, 136.4, 136.3,

128.4 (2C), 127.7 (2C), 122.8 (2C), 119.4 (2C), 102.5, 60.2, 48.4, 28.3, 28.3, 15.6, 15.5, 14.2 ppm; FT-IR

(KBr): ῡ = 3276, 2961, 1674, 1611, 1518, 1446, 1398, 1223, 1149, 1113, 1030, 837 cm-1; MS (70 eV): m/z

= 378.5 (M+), 332.4, 317.4, 305.3 (100%), 277.4, 261.3, 230.3, 219.3, 202.2, 173.2, 157.2, 142.1, 132.1,

118.2, 105.1, 91.1, 77.1, 65.0, 55.1. Anal. Calcd for C23H26N2O3: C, 72.99; H, 6.92; N, 7.40; O, 12.68.

Found: C, 72.76; H, 6.79; N, 7.27; O, 12.47.

The FT-IR spectrum of product (4d)

12

The 1H NMR (400MHz) spectrum of product (4d)

The 13C NMR (100MHz) spectrum of product (4d)

13

The MS spectrum of product (4d)

The H-H COSY spectrum of product (4d)

14

The H-H COSY expanded spectrum of product (4d)

The HSQC spectrum of product (4d)

15

The HSQC expanded spectrum of product (4d)

Methyl1-(4-methoxyphenyl)-4-((4-methoxyphenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate

(4e, C20H20N2O5)

White solid. m.p.: 160-162 °C. 1H NMR (400 MHz, CDCl3): δ= 8.00 (br, s, 1H, NH), 7.64 (d, 2H, 3J = 8.8

Hz, Ar–H), 7.08 (d, 2H, 3J = 8.4 Hz, Ar–H), 6.89 (d, 2H, 3J = 8.4 Hz, Ar–H), 6.84 (d, 2H, 3J = 8.4 Hz, Ar–

H), 4.46 (br, s, 2H, NCH2), 3.79 (s, 6H, ArOCH3), 3.73 (s, 3H, OCH3) ppm; 13C NMR (100 MHz, CDCl3):

δ =165.1, 163.3, 157.1, 156.9, 144.0, 131.9, 131.5, 125.0 (2C), 121.1 (2C), 114.2 (2C), 113.6 (2C), 100.8,

55.5, 55.4, 51.2, 48.4 ppm; FT-IR (KBr): ῡ = 3280, 2943, 1711, 1687, 1643, 1509, 1438, 1400, 1356, 1250,

1202, 1177, 1108, 1034, 828 cm-1. Anal. Calcd for C20H20N2O5: C, 65.21; H, 5.47; N, 7.60; O, 21.72.

Found: C, 64.65; H, 5.09; N, 7.13; O, 21.28.

16

The FT-IR spectrum of product (4e)

The 1H NMR (400MHz) spectrum of product (4e)

17

The 13C NMR (100MHz) spectrum of product (4e)

Ethyl1-(4-methoxyphenyl)-4-((4-methoxyphenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4f,

C21H22N2O5)

White solid. m.p.: 152 °C (Ref. [36] 152-154 °C). 1H NMR (400 MHz, CDCl3): δ= 8.00 (br, s, 1H, NH),

7.65 (br, s, 2H, Ar–H), 7.09 (br, s, 2H, Ar–H), 6.90 (br, s, 2H, Ar–H), 6.84 (br, s, 2H, Ar–H), 4.47 (s, 2H,

NCH2), 4.20 (s, 2H, OCH2CH3), 3.80 (s, 6H, Ar-OMe), 1.24 (s, 3H, OCH2CH3) ppm; 13C NMR (100 MHz,

CDCl3): δ =164.8, 163.5, 157.0, 156.9, 131.9, 131.6, 124.8 (2C), 121.1 (2C), 114.2 (2C), 113.6 (2C),

101.3, 60.1, 55.4, 55.4, 48.5, 14.3 ppm; FT-IR (KBr): ῡ = 3284, 1673, 1644, 1512, 1444, 1401, 1243, 1179,

1112, 1033, 829 cm-1. Anal. Calcd for C21H22N2O5: C, 65.96; H, 5.80; N, 7.33; O, 20.92. Found: C, 65.25;

H, 5.46; N, 7.20; O, 20.55.

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The FT-IR spectrum of product (4f)

The 1H NMR (400MHz) spectrum of product (4f)

19

The 13C NMR (100MHz) spectrum of product (4f)

Methyl1-(4-bromophenyl)-4-((4-bromophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4g,

C18H14Br2N2O3)

White solid. m.p.: 181-182 °C (Ref. [32] 181-182 °C). 1H NMR (400 MHz, CDCl3): δ= 8.02 (br, s, 1H,

NH), 7.66 (d, 2H, 3J = 9.2 Hz, Ar–H), 7.49 (d, 3H, 3J = 8.8 Hz, Ar–H), 7.41 (d, 1H, 3J = 8.4 Hz, Ar–H),

6.99 (d, 2H, 3J = 8.0 Hz, Ar–H), 4.48 (s, 2H, NCH2), 3.77 (s, 3H, OCH3) ppm; 13C NMR (100 MHz,

CDCl3): δ =164.7, 163.5, 142.8, 137.6, 137.4, 132.1 (2C), 131.4 (2C), 124.4 (2C), 120.5 (2C), 118.0,

117.8, 103.8, 51.5, 48.0 ppm; FT-IR (KBr): ῡ = 3289, 1700, 1642, 1586, 1532, 1490, 1391, 1200, 824 cm-1.

Anal. Calcd for C18H14Br2N2O3: C, 46.38; H, 3.03; Br, 34.28; N, 6.01; O, 10.30. Found: C, 45.17; H, 2.71;

N, 5.56; O, 9.74.

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The FT-IR spectrum of product (4g)

The 1H NMR (400MHz) spectrum of product (4g)

21

The 13C NMR (100MHz) spectrum of product (4g)

Ethyl1-(4-bromophenyl)-4-((4-bromophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4h,

C19H16Br2N2O3)

Pale yellow solid. m.p.: 165-166 °C (Ref. [32] 164-165 °C). 1H NMR (400 MHz, CDCl3): δ= 8.03 (br, s,

1H, NH), 7.69 (d, 2H, 3J = 8.4 Hz, Ar–H), 7.50 (d, 2H, 3J = 8.4 Hz, Ar–H), 7.42 (d, 2H, 3J = 8.0 Hz, Ar–

H), 7.01 (d, 2H, 3J = 8.0 Hz, Ar–H), 4.50 (s, 2H, NCH2), 4.24 (s, 2H, OCH2CH3), 1.27 (s, 3H, OCH2CH3)

ppm; 13C NMR (100 MHz, CDCl3): δ =165.1, 163.1, 140.3, 139.8, 138.4, 132.3 (2C), 131.0 (2C), 123.0

(2C), 121.5 (2C), 117.1, 114.5, 106.9, 60.3, 48.8, 14.2 ppm; FT-IR (KBr): ῡ = 3320, 1700, 1639, 1585,

1492, 1384, 1256, 1192, 819 cm-1. Anal. Calcd for C19H16Br2N2O3: C, 47.53; H, 3.36; Br, 33.28; N, 5.83;

O, 10.00. Found: C, 46.67; H, 3.11; N, 5. 43; O, 9.77.

22

The FT-IR spectrum of product (4h)

The 1H NMR (400MHz) spectrum of product (4h)

23

The 13C NMR (100MHz) spectrum of product (4h)

Methyl1-(4-chlorophenyl)-4-((4-chlorophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4i,

C18H14Cl2N2O3)

Cream solid. m.p.: 173-174 °C (Ref. [32] 175-176 °C). 1H NMR (400 MHz, CDCl3): δ= 8.05 (br, s, 1H,

NH), 7.73 (d, 2H, 3J = 6.4 Hz, Ar–H), 7.35 (s, 3H, Ar–H), 7.27 (d, 1H, 3J = 7.6 Hz, Ar–H), 7.07 (s, 2H, Ar–

H), 4.50 (s, 2H, NCH2), 3.78 (s, 3H, OCH3) ppm; 13C NMR (100 MHz, CDCl3): δ = 164.7, 163.5, 142.9,

137.1, 136.9, 130.3, 130.1, 129.2 (2C), 128.4 (2C), 124.1 (2C), 120.2 (2C), 103.6, 51.5, 48.0 ppm; FT-IR

(KBr): ῡ = 3282, 1679, 1646, 1592, 1532, 1494, 1441, 1395, 1292, 1224, 1151, 1094, 829 cm-1. Anal.

Calcd for C18H14Cl2N2O3: C, 57.31; H, 3.74; Cl, 18.80; N, 7.43; O, 12.72. Found: C, 56.27; H, 3.21; N, 7.

11; O, 12.37.

24

The FT-IR spectrum of product (4i)

The 1H NMR (400MHz) spectrum of product (4i)

25

The 13C NMR (100MHz) spectrum of product (4i)

Ethyl1-(4-chlorophenyl)-4-((4-chlorophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4j,

C19H16Cl2N2O3)

Pale yellow solid. m.p.: 167 °C (Ref. [34] 168-170 °C). 1H NMR (400 MHz, CDCl3): δ= 8.04 (s, 1H, NH),

7.74 (d, 2H, 3J = 8.8 Hz, Ar–H), 7.35 (d, 2H, 3J = 7.6 Hz, 3J = 8.8 Hz, Ar–H), 7.27 (d, 2H, 3J = 7.6 Hz, Ar–

H), 7.06 (d, 2H, 3J = 8.4 Hz, Ar–H), 4.50 (s, 2H, NCH2), 4.24 (q, 3H, 3J = 7.2 Hz, OCH2CH3), 1.26 (t, 3H,

3J = 7.2 Hz, OCH2CH3) ppm; 13C NMR (100 MHz, CDCl3): δ =164.4, 163.6, 142.7, 137.2, 137.1, 130.3,

130.0, 129.2 (2C), 128.5 (2C), 124.0 (2C), 120.3 (2C), 104.1, 60.6, 48.1, 14.0 ppm; FT-IR (KBr): ῡ =

3308, 1698, 1647, 1593, 1494, 1393, 1204, 1096, 826 cm-1. Anal. Calcd for C19H16Cl2N2O3: C, 58.33; H,

4.12; Cl, 18.12; N, 7.16; O, 12.27. Found: C, 57.53; H, 3.88; N, 6. 91; O, 12.08.

26

The FT-IR spectrum of product (4j)

The 1H NMR (400MHz) spectrum of product (4j)

27

The 13C NMR (100MHz) spectrum of product (4j)

Methyl1-(3-nitrophenyl)-4-((3-nitrophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4k,

C18H14N4O7)

Yellow solid. m.p.: 204-206 °C. 1H NMR (400 MHz, CDCl3): δ= 8.52 (br, s, 1H, NH), 8.32 (br, s, 1H, Ar–

H), 8.26 (br, s, 1H, Ar–H), 8.03 (br, s, 3H, Ar–H), 7.59 (d, 1H, 3J = 7.2 Hz, Ar–H), 7.48 (d, 2H, 3J = 7.6

Hz, Ar–H), 4.65 (s, 2H, NCH2), 3.85 (s, 3H, OCH3) ppm; 13C NMR (100 MHz, CDCl3): δ =165.2, 162.5,

149.6, 149.0, 143.1, 141.0, 140.8, 132.1, 130.6, 128.4, 126.4, 120.7, 118.4, 116.2, 114.9, 110.6, 53.0, 50.1

ppm; FT-IR (KBr): ῡ = 3429, 1704, 1648, 1616, 1530, 1351, 1318, 1263, 735 cm-1. MS (70 eV): m/z =

398.3 (M+), 339.3, 218.2, 190.2, 174.1, 164.1, 150.1, 138.1, 128.1, 116.1, 103.1, 92, 76 (100%), 65, 51.

Anal. Calcd for C18H14N4O7: C, 54.28; H, 3.54; N, 14.07; O, 28.12. Found: C, 53.92; H, 3.43; N, 13.88; O,

27.90.

28

The FT-IR spectrum of product (4k)

The 1H NMR (400MHz) spectrum of product (4k)

29

The 13C NMR (100MHz) spectrum of product (4k)

The MS spectrum of product (4k)

30

The H-H COSY spectrum of product (4k)

The H-H COSY expanded spectrum of product (4k)

31

The HSQC spectrum of product (4k)

The HSQC expanded spectrum of product (4k)

32

Ethyl1-(3-nitrophenyl)-4-((3-nitrophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4l,

C19H16N4O7)

Cream solid. m.p.: 190 °C. 1H NMR (400 MHz, CDCl3): δ= 8.52 (s, 1H, NH), 8.35 (br, s, 1H, Ar–H), 8.26

(s, 1H, Ar–H), 8.06 (d, 1H, 3J = 6.4 Hz, Ar–H), 7.99 (br, s, 2H, Ar–H), 7.59 (br, s, 1H, Ar–H), 7.47 (br, s,

2H, Ar–H), 4.65 (s, 2H, NCH2), 4.33 (s, 2H, OCH2CH3), 1.34 (s, 3H, OCH2CH3) ppm; 13C NMR (100

MHz, CDCl3): δ = 165.4, 162.8, 148.5, 148.0, 142.3, 139.9, 139.3, 131.0, 129.5 (2C), 126.9 (2C), 125.3

(2C), 119.5 (2C), 117.1, 114.8, 113.8, 109.7, 60.6, 49.1, 14.3 ppm; FT-IR (KBr): ῡ = 3303, 1701, 1648,

1615, 1529, 1398, 1354, 1204, 738 cm-1; MS (70 eV): m/z = 412.3 (M+), 339.1, 219.2, 190.1, 174.1,

163.1, 150.1 (100%), 139.1, 128.1, 116.1, 103.1, 92, 76, 65, 51. Anal. Calcd for C19H16N4O7: C, 55.34; H,

3.91; N, 13.59; O, 27.16. Found: C, 54.95; H, 3.55; N, 13.38; O, 26.96.

The FT-IR spectrum of product (4l)

33

The 1H NMR (400MHz) spectrum of product (4l)

The 13C NMR (100MHz) spectrum of product (4l)

34

The MS spectrum of product (4l)

The H-H COSY spectrum of product (4l)

35

The H-H COSY expanded spectrum of product (4l)

The HSQC spectrum of product (4l)

36

The HSQC expanded spectrum of product (4l)

ethyl1-(4-nitrophenyl)-4-((4-nitrophenyl)amino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (4m,

C19H16N4O7)

Yellow solid. m.p.: 206-208 °C. 1H NMR (400 MHz, CDCl3): δ= 8.35 (s, 1H, NH), 8.30 (d 2H, 3J = 8.4

Hz, Ar–H), 8.21 (d, 2H, 3J = 8.8 Hz, Ar–H), 8.01 (d, 2H, 3J = 8.8 Hz, Ar–H), 7.19 (d, 2H, 3J = 8.4 Hz, Ar–

H), 4.65 (s, 2H, NCH2), 4.32 (s, 2H, OCH2CH3), 1.32 (t, 3H, OCH2CH3) ppm; 13C NMR (100 MHz,

CDCl3): δ =165.1, 162.5, 146.8, 144.1, 143.7, 141.9, 139.3, 125.0 (2C), 124.1 (2C), 119.6 (2C), 118.5

(2C), 111.9, 60.8, 48.8, 14.2 ppm; FT-IR (KBr): ῡ = 3312, 1710, 1648, 1595, 1510, 1383, 1337, 1266,

1109, 1026, 848, 751 cm-1; MS (70 eV): m/z = 412.1 (M+), 339.2, 219.1, 190.1, 174.1, 163.1, 150.1, 129.1,

117.1, 103.0, 92, 76 (100%), 65, 51.1. Anal. Calcd for C19H16N4O7: C, 55.34; H, 3.91; N, 13.59; O, 27.16.

Found: C, 54.46; H, 3.12; N, 13.08; O, 26.80.

37

The FT-IR spectrum of product (4m)

The 1H NMR (400MHz) spectrum of product (4m)

38

The 13C NMR (100MHz) spectrum of product (4m)

The MS spectrum of product (4m)

39

The H-H COSY spectrum of product (4m)

The H-H COSY expanded spectrum of product (4m)