Molecules 2014, 19
1984
(
E)-3-(4-Fluorobenzylidene)-1-methylpiperidin-4-one (4d). Yield 75%; Yellow solid; m.p. 38–39 °C;
1
H-NMR (400 MHz): δ 2.45 (s, 3H), 2.67 (t, J = 6.0 Hz, 2H), 2.82 (t, J = 6.0 Hz, 2H), 3.62 (s, 1H),
1
3
3
5
1
.63 (s, 1H), 7.08–7.12 (m, 2H), 7.32–7.35 (m, 2H), 7.53 (s, 1H); C-NMR (100 MHz): δ 39.1, 46.2,
2.7, 57.6, 115.7 (d, J = 22 Hz), 131.0 (d, J = 3 Hz), 132.3 (d, J = 8 Hz), 132.7 (d, J = 1 Hz), 134.7,
+
62.9 (d, J = 250 Hz), 197.6; MS: m/z 220 [M+H] .
(
E)-3-(4-Bromobenzylidene)-1-methylpiperidin-4-one (4e). Yield 73%; Yellow solid; m.p. 63–64 °C;
H-NMR (400 MHz): δ 2.44 (s, 3H), 2.67 (t, J = 6.0 Hz, 2H), 2.82 (t, J = 6.0 Hz, 2H), 3.59 (s, 1H),
1
1
3
3
3
.60 (s, 1H), 7.20 (d, J =8.4 Hz, 2H), 7.48 (s, 1H), 7.53 (d, J = 8.4 Hz, 2H); C-NMR (100 MHz): δ
+
9.1, 46.2, 52.8, 57.7, 123.4, 131.8, 131.8, 133.6, 133.8, 134.5, 197.6; MS: m/z 302 [M+Na] .
(
E)-3-(3,4-Dichlorobenzylidene)-1-methylpiperidin-4-one (4f). Yield 80%; Yellow solid; m.p. 73–74 °C;
1
H-NMR (400 MHz): δ 2.45 (s, 3H), 2.68 (t, J = 6.0 Hz, 2H), 2.82 (t, J = 6.0 Hz, 2H), 3.59 (s, 1H),
1
3
3
.60 (s, 1H), 7.15–7.18 (m, 1H), 7.41–7.43 (m, 2H), 7.47–7.49 (m, 1H); C-NMR (100 MHz): δ 39.2,
+
4
6.2, 52.7, 57.5, 129.4, 130.6, 131.8, 132.9, 133.1, 133.2, 134.5, 134.9, 197.4; MS: m/z 270 [M] .
1
(
E)-1-Methyl-3-(4-methylbenzylidene)piperidin-4-one (4g). Yield 54%; Brown liquid; H-NMR
400 MHz): δ 2.37 (s, 3H), 2.44 (s, 3H), 2.66 (t, J = 6.0 Hz, 2H), 2.80 (t, J = 6.0 Hz, 2H), 3.65 (s, 1H),
(
13
3
.66 (s, 1H), 7.20 (d, J = 8.0 Hz, 2H), 7.25 (d, J = 8.4 Hz, 2H), 7.56 (s, 1H); C-NMR (100 MHz): δ
+
2
1.3, 39.0, 46.2, 52.7, 57.8, 129.2, 130.5, 132.0, 132.1, 136.0, 139.3, 197.6; MS: m/z 216 [M+H] .
(
E)-3-(4-Methoxybenzylidene)-1-methylpiperidin-4-one (4h). Yield 50%; Yellow solid; m.p. 60–61 °C.
H-NMR (400 MHz): δ 2.46 (s, 3H), 2.66 (t, J = 6.0 Hz, 2H), 2.81 (t, J = 6.0 Hz, 2H), 3.66 (s, 2H),
1
13
3
3
2
.84 (s, 3H), 6.93 (d, J = 8.8 Hz, 2H), 7.33 (d, J = 8.4 Hz, 2H), 7.56 (s, 1H); C-NMR (100 MHz): δ
9.1, 46.3, 52.7, 55.4, 58.0, 114.1, 127.6, 130.9, 132.3, 132.5, 136.0, 160.4, 197.7. MS: m/z
+
32 [M+H] .
(
E)-3-(3-Chlorobenzylidene)-1-methylpiperidin-4-one (4i). Yield 81%; Yellow solid; m.p. 57–58 °C;
H-NMR (400 MHz): δ 2.45 (s, 3H), 2.68 (t, J = 6.0 Hz, 2H), 2.82 (t, J = 6.0 Hz, 2H), 3.61 (s, 1H),
1
1
3
3
5
.62 (s, 1H), 7.20–7.22 (m, 1H), 7.31–7.34 (m, 3H), 7.48 (s, 1H); C-NMR (100 MHz): δ 39.1, 46.2,
+
2.7, 57.5, 128.4, 129.0, 129.8, 129.9, 134.1, 134.2, 134.5, 136.7, 197.5; MS: m/z 235 [M+H] .
(
E)-3-(3-Bromobenzylidene)-1-methylpiperidin-4-one (4j). Yield 86%; Yellow solid; m.p. 51–52 °C;
H-NMR (400 MHz): δ 2.44 (s, 3H), 2.67 (t, J = 6.0 Hz, 2H), 2.82 (t, J = 6.0 Hz, 2H), 3.60 (s, 1H),
1
1
3
3
1
.61 (s, 1H), 7.26–7.27 (m, 2H), 7.46–7.48 (m, 3H); C-NMR (100 MHz): δ 39.1, 46.1, 52.7, 57.4,
+
22.5, 128.7, 130.0, 131.8, 132.8, 133.9, 134.2, 136.9, 197.4; MS: m/z 302 [M+Na] .
1
(
E)-3-(3-Methoxybenzylidene)-1-methylpiperidin-4-one (4k). Yield 65%; Brown liquid; H-NMR
400 MHz): δ 2.44 (s, 3H), 2.67 (t, J = 6.0 Hz, 2H), 2.81 (t, J = 6.0 Hz, 2H), 3.64 (s, 2H), 3.82 (s, 3H),
(
1
3
6
5
.87–6.95 (m, 3H), 7.30–7.34 (m, 1H), 7.54 (s, 1H); C-NMR (100 MHz): δ 39.1, 46.2, 52.8, 55.3,
+
7.7, 114.6, 115.9, 122.8, 129.5, 133.2, 135.8, 136.2, 159.5, 197.8; MS: m/z 232 [M+H] .
1
(
E)-3-(2-Fluorobenzylidene)-1-methylpiperidin-4-one (4l). Yield 84%; Brown liquid; H-NMR
400 MHz): δ 2.42 (s, 3H), 2.68 (t, J = 6.0 Hz, 2H), 2.82 (t, J = 6.0 Hz, 2H), 3.52 (s, 2H), 7.08–7.18
(