1744
M. T. Richers et al.
FEATURE ARTICLE
1H NMR (500 MHz, CDCl3): δ = 7.63 (d, J = 8.2 Hz, 2 H), 7.56 (d,
J = 8.2 Hz, 2 H), 7.47 (d, J = 2.3 Hz, 1 H), 7.00 (d, J = 2.3 Hz, 1 H),
5.09 (d, J = 2.1 Hz, 1 H), 4.84 (br s, 1 H), 3.71 (d, J = 16.3 Hz, 1 H),
3.58 (d, J = 16.3 Hz, 1 H), 2.37 (s, 3 H).
MS-ESI: m/z = 189.3 [M + H]+.
In addition, 34a was also isolated.
34a
13C NMR (125 MHz, CDCl3): δ = 144.8, 137.9, 132.5, 130.6 (q,
Yield: 24.8 mg (38%); white solid; mp 251–253 °C; Rf = 0.19
(hexanes–EtOAc 70:30, v/v).
JC,F = 31.4 Hz), 129.1, 127.6, 125.6 (q, JC,F = 3.8 Hz), 123.9 (q,
JC,F = 272.3 Hz), 121.6, 108.7, 108.5, 74.3, 51.4, 40.6.
MS-ESI: m/z = 451.1 [M + H]+.
IR (KBr): 3318, 2024, 2955, 2855, 2807, 1612, 1498, 1479, 1450,
1368, 1308, 1216, 1115, 1094, 1072, 1020, 963, 892, 871, 749 cm–1.
1H NMR (500 MHz, CDCl3): δ = 7.30–7.21 (comp, 4 H), 7.15–7.02
(comp, 3 H), 7.02–6.97 (m, 1 H), 6.94–6.81 (comp, 3 H), 6.71 (app
d, J = 8.0 Hz, 1 H), 5.82 (s, 1 H), 5.31 (d, J = 3.2 Hz, 1 H), 4.84 (br
s, 1 H), 4.54 (s, 1 H), 3.87–3.82 (comp, 4 H), 3.45–3.31 (m, 2 H),
2.84 (app dt, J = 11.6, 4.6 Hz, 2 H).
13C NMR (125 MHz, CDCl3): δ = 146.3, 144.4, 140.7, 130.7, 129.1,
129.0, 128.8, 128.7, 128.5, 127.9, 125.3, 124.4, 124.2, 123.7, 123.3,
123.3, 120.00, 117.4, 84.8, 70.4, 67.7, 64.5, 50.5.
Compound 31
Following the general microwave procedure, 31 was obtained from
2-aminobenzophenone (0.5 mmol) and pyrrolidine (3 equiv) after 1
h at 250 °C; yield: 65.9 mg (53%) (1:1.5 mixture of diastereomers);
yellow semi-solid; Rf = 0.36 (hexanes–EtOAc, 70:30 v/v).
IR (KBr): 3219, 2956, 2871, 2368, 2602, 1473, 1364, 1300, 1248,
1152, 1089, 1029, 1007, 940, 923, 756, 703 cm–1.
1H NMR (500 MHz, CDCl3): δ = 7.39–7.27 (comp, 7 H), 7.24–7.19
(comp, 3 H), 7.08 (app td, J = 8.4, 1.6 Hz, 1 H), 7.02 (app td, J =
7.5, 1.5 Hz, 1 H), 6.91 (dd, J = 7.5, 1.6 Hz, 1 H), 6.73–6.60 (comp,
3 H), 6.58–6.53 (comp, 2 H), 4.92 (s, 1 H), 4.58 (s, 1 H), 4.37 (d, J =
4.3 Hz, 1 H), 4.11 (br s, 1 H), 3.89–3.84 (m, 1 H), 3.75 (br s, 1 H),
3.05 (app td, J = 8.5, 3.7 Hz, 1 H), 2.90 (app td, J = 8.9, 2.2 Hz, 1
H), 2.86–2.77 (m, 1 H), 2.24–2.12 (comp, 2 H), 2.10–1.85 (comp, 4
H), 1.85–1.72 (comp, 2 H), 1.66–1.58 (m, 1 H).
13C NMR (125 MHz, CDCl3): δ = 144.2, 143.6, 143.0, 129.6, 129.4,
128.8, 128.6, 128.3, 128.1, 127.6, 127.5, 127.1, 126.8, 126.6, 119.2,
118.6, 117.1, 116.6, 113.9, 104.7, 73.7, 69.9, 65.0, 61.0, 50.8, 50.0,
32.7, 30.4, 21.3, 20.0.
MS-ESI: m/z = 397.0 [M + H]+.
Compound 34b
A 10 mL round-bottom flask was charged with 2-aminobenzalde-
hyde (8k; 0.363 g, 3 mmol), absolute ethanol (4 mL), and pyrro-
lidine (0.083 mL, 1 mmol) and was stirred at r.t. for 2 days. After
this time, the solvent was removed in vacuo and the residue was pu-
rified by silica gel chromatography; yield: 232.5 mg (61%); light
yellow solid; mp 184–187 °C; Rf = 0.26 (hexanes–EtOAc, 70:30
v/v).
IR (KBr): 3375, 3050, 2967, 2800, 1734, 1610, 1572, 1494, 1480,
1447, 1369, 1334, 1305, 1243, 1218, 1128, 1070, 1007, 963, 952,
873, 792, 742 cm–1.
MS-ESI: m/z = 251.1 [M + H]+.
1H NMR (500 MHz, CDCl3): δ = 7.31–7.18 (comp, 3 H), 7.14 (app
d, J = 7.7 Hz, 1 H), 7.11–7.00 (comp, 3 H), 7.00–6.93 (comp, 2 H),
6.92–6.80 (comp, 2 H), 6.71 (app d, J = 7.6 Hz, 1 H), 5.95 (s, 1 H),
5.29 (d, J = 1.8 Hz, 1 H), 4.85 (br s, 1 H), 4.50 (s, 1 H), 3.37–3.22
(m, 2 H), 2.95–2.78 (m, 2 H), 2.03–1.82 (comp, 4 H).
13C NMR (125 MHz, CDCl3): δ = 145.9, 144.2, 140.8, 130.2, 129.4,
128.9, 128.5, 128.4, 128.3, 127.8, 127.8, 124.6, 124.2, 123.6, 123.5,
123.1 119.9, 117.4, 83.8, 70.8, 63.8, 51.2, 23.8.
Compound 32
Following the general microwave procedure, 32 was obtained from
2-aminoacetophenone (0.5 mmol) and pyrrolidine (3 equiv) after 1
h at 250 °C; yield: 25.9 mg (28%) (1:1.4 mixture of diastereomers);
tan oil; Rf = 0.25 (EtOAc–MeOH, 95:5 v/v).
IR (KBr): 3330, 2965, 2874, 1633, 1609, 1496, 1445, 1372, 1342,
1266, 1188, 1101, 1035, 938, 753 cm–1.
1H NMR (500 MHz, CDCl3): δ = 7.12–7.06 (m, 1 H), 7.06–6.93
(comp, 3 H), 6.79–6.71 (m, 1 H), 6.69–6.61 (m, 1 H), 6.58–6.54 (m,
1 H), 6.48–6.42 (m, 1 H), 4.70 (app t, J = 4.5 Hz, 1 H), 4.07–4.02
(m, 1 H), 3.96–3.90 (m, 1 H), 3.90–3.83 (m, 1 H), 3.64 (br s, 1 H),
3.13 (app td, J = 9.0, 4.3 Hz, 1 H), 2.97 (app td, J = 8.3, 4.3 Hz, 1
H), 2.72–2.61 (m, 1 H), 2.52–2.42 (m, 1 H), 2.20–1.80 (comp, 7 H),
1.75–1.63 (comp, 2 H), 1.52–147 (comp, 3 H), 1.46–1.42 (comp, 3
H).
MS-ESI: m/z = 381.0 [M + H]+.
Compound 36
Following the general microwave procedure, 36 was obtained from
2-aminobenzaldehyde (8k; 0.25 mmol) and trans-4-hydroxy-L-pro-
line (2.1 equiv) after 15 min at 150 °C in n-butanol (1 mL); yield:
8.4 mg (18%) (1:1.2 mixture of diastereomers); white solid; mp
126–129 °C; Rf = 0.17 (EtOAc–MeOH, 90:10 v/v).
13C NMR (125 MHz, CDCl3): δ = 143.1, 141.6, 128.0, 127.0 (6),
127.0 (5), 126.1, 125.3, 122.6, 118.5, 117.0, 115.5, 113.8, 72.6,
64.2, 56.2, 52.4, 49.6, 47.9, 32.9, 31.2, 24.9, 21.0, 20.4, 19.1.
IR (KBr): 3284, 2922, 2806, 2361, 1610, 1491, 1379, 1267, 1152,
1091, 1018, 822, 746 cm–1.
1H NMR (500 MHz, CDCl3): δ = 7.07–6.92 (comp, 4 H), 6.77 (app
t, J = 7.6 Hz, 1 H), 6.70 (app t, J = 7.3 Hz, 1 H), 6.60 (app d, J = 7.8
Hz, 1 H), 6.51 (app d, J = 8.0 Hz, 1 H), 4.56 (br s, 1 H), 4.52–4.47
(m, 1 H), 4.47–4.40 (m, 1 H), 4.23–4.15 (comp, 2 H), 4.07 (d, J =
15.8 Hz, 1 H), 3.88 (d, J = 15.8 Hz, 1 H), 3.83 (d, J = 16.0 Hz, 1 H),
3.30 (dd, J = 9.7, 5.9 Hz, 1 H), 3.17 (dd, J = 10.4, 6.2 Hz, 1 H), 2.96
(app d, J = 10.4 Hz, 1 H), 2.73 (app d, J = 9.7 Hz, 1 H), 2.50–2.39
(comp, 2 H), 2.20–2.00 (comp, 3 H), 1.76 (app d, J = 13.8 Hz, 1 H).
MS-ESI: m/z = 189.1 [M + H]+.
Compound 33
Following the general microwave procedure, 33 was obtained from
2-aminobenzaldehyde (8k; 0.5 mmol) and morpholine (3 equiv) af-
ter 2 h at 250 °C; yield: 11.8 mg (12%); light yellow solid; mp 78–
81 °C; Rf = 0.36 (EtOAc–MeOH, 90:10 v/v).
IR (KBr): 3357, 2979, 2852, 1608, 1493, 1456, 1362, 1342, 1290,
1274, 1126, 1045, 1030, 930, 857, 743, 699 cm–1.
13C NMR (125 MHz, CDCl3): δ = 142.7, 142.6, 127.4, 127.3, 119.7,
119.3, 118.6, 118.4, 116.0, 114.7, 104.8, 103.0, 70.9, 70.8, 70.4,
69.9, 60.8, 59.6, 50.1, 49.3, 44.1, 43.3.
1H NMR (500 MHz, CDCl3): δ = 7.04 (app td, J = 7.8, 1.6 Hz, 1 H),
6.93 (app d, J = 7.5 Hz, 1 H), 6.72 (app td, J = 7.5, 1.2 Hz, 1 H), 6.58
(dd, J = 7.8, 1.1 Hz, 1 H), 4.11–3.73 (comp, 6 H), 3.70 (d, J = 15.3
Hz, 1 H), 3.58 (dd, J = 11.3, 5.5 Hz, 1 H), 3.06–2.87 (m, 1 H), 2.52–
2.32 (m, 1 H).
13C NMR (125 MHz, CDCl3): δ = 141.7, 127.4, 127.0, 119.0, 118.6,
115.3, 69.8, 67.2, 67.1, 55.1, 49.2.
MS-ESI: m/z = 191.2 [M + H]+.
Compound 37
Following the general microwave procedure, 37 was obtained from
2-aminobenzaldehyde (8k; 0.25 mmol) and trans-3-hydroxy-L-pro-
line (2.1 equiv) after 15 min at 150 °C in n-butanol (1 mL); yield:
Synthesis 2013, 45, 1730–1748
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