A.A.E. Mourad, Y.W. Rizzk, I. Zaki et al.
Journal of Molecular Structure 1242 (2021) 130722
2.3.2. Ethyl (E)-3-(2-((E)-benzylidene)
(1.76), 180 (1.84), 179 (53.93), 178 (2.66), 172 (3.44), 171 (15.74),
169 (1.92), 162 (1.51), 161 (1.17), 155 (4.07), 148 (1.42), 143 (1.05),
135 (1.38 ), 128 (3.65), 120 (5.87), 119 (40.26), 117 (2.38), 105
(6.74), 104 (69.09), 103 (4.45), 102 (5.72), 93 (25.52), 92 (25.58),
91 (6.18), 90 (6.99), 89 (20.91), 88 (4.56), 78 (18.99), 77 (62.79),
76 (100), 75 (2.77), 66 (6.04), 65 (25.82), 64 (5.14), 63 (15.83), 61
(3.25), 60 (74.14), 59 (7.25), 51 (16.18), 50 (4.86). Anal. Calcd for
C22H23N5O2S (421): C, 62.71; H, 5.46; N, 16.63. Found: C, 26.49; H,
5.25; N, 16.46.
hydrazine-1-carbothioamido)-2-cyano-3-(4-methoxyphenyl) acrylate
(4b)
Pale yellow crystals, yield: 64%, m.p. 151-153°C. IR (KBr) υmax
=3422, 3254 (NH), 2215 (CN), 1717 (C=O), 1611 (C=N), 1588, 1559
(C=C), 1183, 1089, 1018 (C-O) cm−1
.
1H-NMR (DMSO-d6, 400 MHz)
δ: 1.30 (t, 3H, CH3), 3.88 (s, 3H, OCH3), 4.30 (q, 2H, OCH2), 7.15-8.11
(m, 9H, Ar-H), 8.24 (br-s; 1H, NH), 8.32 (s, 1H, CH=N), 11.47 (s, 1H,
NH) ppm. 13C- NMR (DMSO-d6, 100 MHz) δ: 178.4 (C=S), 164.03
(C=O), 162.85 (CH=N), 154.97 (C-O), 142.67 (NH-C-Ar), 134.66,
134.02, 130.29, 129.82, 129.12, 127.77, 124.43, 116.76, 115.46 (C-
aromatic and olefinic), 98.99 (CN), 62.57 (OCH2), 56.25 (OCH3),
14.52 (CH3) ppm. Ms: m/z(%)= 408 (M+, unstable), 385 (4.20), 383
(1.06), 247 (1.58), 231 (99.16), 230 (8.43), 216 (2.75), 203 (41.87),
202 (4.36), 199 (1.32), 188 (3.94), 187 (6.55), 186 (65.52), 180 (1.11),
179 (100), 172 (4.88), 160 (2.15), 159 (11.96), 158 (7.17), 157 (15.43),
148 (1.49), 136 (1.95), 130 (1.61), 129 (1.11), 128 (2.19), 119 (23.31),
117 (1.68), 116 (4.02), 115 (1.93), 105 (7.61), 104 (42.68), 103 (2.91),
102 (3.76), 93 (11.29), 92 (7.58), 91 (1.71), 90 (3.73), 89 (10.46), 88
(4.35), 78 (7.49), 77 (57.60), 76 (60.30), 65 (5.99), 64 (3.36), 63
(8.01), 62 (5.91), 60 (55.53), 51 (4.16), 50 (3.89). Anal. Calcd for
C21H20N4O3S (408): C, 61.76; H, 4.90; N, 13.72. Found: C, 61.66; H,
4.71; N, 13.53.
2.4. General procedure for the synthesis of 1,2-bis ((E)-benzylidene)
hydrazines (6a-c) and 2-(E)-1-benzylidene-2-phenylhydrazine (8a-c)
A mixture of ester derivative 4 (0.01 mol) and hydrazine deriva-
tive (0.02 mol) (namely, hydrazine hydrate and phenyl hydrazine)
in absolute ethanol (20 mL) was reflexed for 3 h. The reaction mix-
ture was cooled, then poured into ice water, and neutralized by
few drops of diluted hydrochloric acid (2%). The solid formed was
filtered off, washed with water, dried, and crystallized from proper
solvent to give compounds 6a–c and 8a–c.
2.4.1. 1,2-Bis ((E)-benzylidene) hydrazine (6a)
Yellow crystals, yield: 6l%, m.p. 205–207 °C, crystallized from
ethanol/ H2O (3:1). IR (KBr) υmax = 1657 (C=N), 1605, 1574
2.3.3. Ethyl (E)-3-(2-((E)-benzylidene) hydrazine-1-carbothioamido)-
2-cyano-3-(4-hydroxy-3-methoxyphenyl) acrylate
(4c)
(C=C) cm−1
.
1H-NMR (DMSO-d6, 400 MHz) δ: 7.55 (t, 3H, Ar-H),
7.90 (d, 2H, Ar-H), 8.74 (s, 1H, CH=N) ppm. 13C-NMR (DMSO-d6,
100 MHz) δ: 162.04 (CH=N), 134.25, 131.89, 129.42, 128.86 (C-
aromatic) ppm. MS: m/z(%)= 209 (M++1, 15.8), 208 (M+, 28.44),
207 (M+-1, 31.69), 181 (7.81), 180 (17.96), 179 (2.60), 178 (4.87),
165 (1.57), 152 (1.73), 132 (4.48), 131 (55.04), 105 (3.42), 104
(20.48), 103 (3.58), 102 (2.06), 91 (2.78), 90 (7.80), 89 (18.80), 78
(17.51), 77 (100), 76 (10.08), 75 (4.59), 64 (8.99), 63 (22.85), 51
(91.66), 50 (15.44). Anal Calcd for C14 H12N2 (208): C, 80.77; H,
5.77; N, 13.46. Found: C, 80.66; H, 5.55; N, 13.23.
Pale yellow crystals, yield: 63%, m.p. 153–155 °C. IR (KBr)
υmax = 3421 (OH), 3378, 3254 (NH), 2219 (CN), 1703 (C=O), 1605
(C=N), 1583, 1543 (C=C), 1180, 1093, 1018 (C-O) cm−1
.
1H-NMR
(DMSO-d6, 400 MHz) δ: 1.29 (t, 3H, CH3), 3.82 (s, 3H, OCH3), 4.29
(q, 2H, OCH2), 6.96-7.81 (m, 9H, Ar-H), 8.02 (br-s; 1H, OH), 8.06
(s, 1H, NH), 8.23 (s, 1H, CH=N), 11.46 (s, 1H, NH) ppm. 13C-NMR
(DMSO-d6, 100 MHz) δ: 178.40 (C=S), 163.11 (C=O), 155.41, 153.17
(C-O), 148.25 (CH=N), 142.75 (Ar-C-NH), 134.62, 130.30, 129.12,
128.87, 127.75, 127.66, 123.29, 117.12, 116.46, 114.42 (C-aromatic
and olefinic), 97.43 (CN), 62.43 (OCH2), 56.00 (OCH3), 14.52 (CH3)
ppm. MS: m/z (%)=424 (M+, unstable), 249 (3.81), 248 (30.26),
247 (95.77), 246 (4.35), 220 (5.82), 219 (21.50), 218 (17.33), 216
(3.20), 204 (3.99), 203 (2.85), 202 (20.33), 201 (1.70), 192 (1.28), 88
(2.00), 187 (2.74), 168 (6.78), 182 (5.14), 181 (14.76), 180 (100), 179
(71.99), 176 (18.05), 175 (12.40), 172 (6.15), 171 (4.73), 170 (29.39),
162 (2.98), 160 (6.43), 159 (8.52), 158 (13.28), 148 (7.61), 147 (2.11),
146 (6.59), 145 (4.33), 142 (8.19), 133 (5.05), 132 (12.76), 131 (5.38),
130 (10.71), 124 (2.15), 120 (7.83), 119 (30.20), 117 (4.71), 115
(2.70), 114 (18.00), 106 (4.94), 105 (8.85), 104 (33.87), 103 (14.37),
102 (14.54), 93 (15.24), 92 (11.53), 91 (10.19), 90 (7.36), 89 (16.60),
86 (4.54), 65 (14.49), 64 (5.21), 63 (11.85), 62 (6.14), 60 (27.11), 59
(4.08), 52 (9.8), 51 (18.08), 50 (5.43). Anal. Calcd for C21H20N4O4S
(424): C, 59.43; H, 4.72; N, 13.21. Found: C, 59.29; H, 4.58; N, 13.03.
2.4.2. 1,2-Bis ((E)-4-methoxybenzylidene) hydrazine (6b)
Pale yellow crystals, yield: 63%, m.p. 198–200 °C, crystallized
from ethanol/ H2O (3:1). IR (KBr) υmax = 1604 (C=N), 1581, 1510
(C=C), 1168, 1027 (C-O) cm−1
.
1H-NMR (DMSO-d6, 400 MHz) δ:
3.84 (s, 3H, OCH3), 7.06 (d, 2H, Ar-H), 7.82 (d, 2H, Ar-H), 8.65 (s,
1H, CH=N) ppm. 13C-NMR (DMSO-d6, 100 MHz) δ: 162.14, 162.04
(CH=N), 161.36, 161.04 (C-O), 130.67, 130.47, 129.38, 128.71, 127.02,
126.83, 114.91, 114.88 (C-aromatic for two isomer) ppm. MS: m/z
(%) = 269 (M++1, 38.39), 268 (M+, 66.08), 267 (M+-1, 27.56), 253
(3.31), 241 (7.66), 240 (11.0l), 238 (1.37), 237 (1.79), 226 (2.81), 225
(8.06), 224 (3.60), 210 (3.13), 209 (1.48), 198 (1.70), 197 (3.35), 183
(2.72), 182 (5.03), 181 (2.06), 162 (8.90), 161 (87.89), 160 (4.64),
159 (3.92), 146 (3.61), 135 (6.99), 134 (35.46), 133 (10.12), 121
(5.11), 120 (7.71), 119 (9.78), 118 (5.98), 108 (8.73), 107 (12.39), 105
(19.87), 104 (6.05), 103 (10.87), 92 (69.25), 91 (85.77), 90 (28.00),
89 (32.52), 79 (11.71), 78 (16.62), 77 (100), 76 (18.18), 75 (5.79), 65
(12.81), 64 (28.43), 63 (35.75), 62 (6.91), 51 (30.81), 50 (7.33). Anal.
Calcd for C16 H16 N2O2 (268): C, 71.64; H, 5.97; N, 10.45. Found: C,
71.47; H, 5.68; N, 10.22.
2.3.4. Ethyl (E)-3-(2-((E)-benzylidene)
hydrazine-1-carbothioamido)-2-cyano-3-(4-(dimethylamino) phenyl)
acrylate (4d)
Pale yellow crystals, yield: 71%, m.p. 162-164 °C. IR (KBr)
υmax = 3422, 3254 (NH), 2209 (CN), 1705 (C=O), 1611 (C=N),
2.4.3. 1,2-Bis ((E)-4-N, N-dimethylaminobenzylidene) hydrazine (6c)
1588, 1570 (C=C), 1172, 1089 (C-O) cm−1
.
1H-NMR (DMSO-d6,
Pale orange crystals, yield: 63%, m.p. 210–212 °C, crystallized
400 MHz) δ: 1.29 (t, 3H, CH3), 3.10 (s, 6H, N(CH3)2), 4.27 (q, 2H,
OCH2), 6.84–8.05 (m, 9H, Ar-H), 8.12 (s, 1H, NH), 8.06 (s, 1H, NH),
8.24 (s, 1H, CH=N), 11.46 (s, 1H, NH) ppm. 13C-NMR (DMSO-d6,
100 MHz) δ: 178.39 (C=S), 163.97 (C=O), 154.68 (CH=N), 154.22
(N-C-Ar), 142.67 (Ar-C-NH), 134.65, 134.30, 130.30, 129.13, 127.77,
127.66, 118.75, 118.09, 116.46, 112.12 (C-aromatic and olefinic),
92.42 (CN), 61.93 (OCH2), 39.32 (N(CH3)2), 14.64 (CH3) ppm. MS:
m/z (%) = 421 (M+, unstable),245(8.03), 244 (58.35), 243 (3.20),
217 (2.46), 216 (24.75), 215 (37.15), 214 (2.01), 199 (6.88), 181
from DMF/ H2O (1:1). IR (KBr) υmax = 2913, 2806 (C-H aliphatic),
−1
1604 (C=N), 1583, 1524 (C=C) cm
.
1H-NMR (DMSO-d6, 400
MHz) δ: 3.01 (s, 6H, N(CH3)2), 6.77 (d, 2H, Ar-H), 7.68 (d, 2H, Ar-H),
8.51 (s, 1H, CH=N) ppm. 13C-NMR (DMSO-d6, 100 MHz) δ: 160.15,
160.02 (CH=N), 152.81, 152.44 (N-C-Ar), 130.47, 129.98, 129.34,
128.49, 112.15, 112.12 (C-aromatic for two isomer), 39.49, 39.29
(N(CH3)2) ppm. MS: m/z (%)= 294 (M+, unstable), 252 (15.60),
251 (100), 250 (46.90), 224 (10.03), 223 (44.49), 222 (22.79), 208
(7.07), 207 (18.50), 179 (4.48), 178 (4.08), 174 (18.82), 147 (34.24),
3