8344
H.-Y. Xu et al. / Tetrahedron 68 (2012) 8340e8346
1.98e1.93 (m, 2H) ppm. Isomer 1H NMR (400 MHz, CDCl3):
110.0e111.5 ꢀC. IR (KBr):
1090, 1018, 798, 692, 563 cmꢁ1. Characterized as a 4:1 di-
astereomeric mixture. 1H NMR (400 MHz, CDCl3):
n
¼3424, 3055, 2954, 1670, 1424, 1268,
d
¼8.23e8.11 (m, 3H), 8.06 (d, J¼8.1 Hz, 1H), 7.63e7.55 (m, 5H), 6.46
(d, J¼11.7 Hz, 1H), 5.51 (d, J¼11.7 Hz, 1H), 3.42e3.37 (m, 1H),
d¼7.90 (d,
2.86e2.83 (m, 1H), 2.17e2.14 (m, 2H), 2.02 (s, 3H), 1.85e1.79 (m,
J¼7.5 Hz, 2H), 7.45e7.38 (m, 5H), 7.20e7.14 (m, 3H), 6.13 (d,
J¼11.8 Hz,1H), 5.63 (d, J¼11.8 Hz,1H), 3.43e3.35 (m,1H), 3.05e3.03
(m, 1H), 2.28e2.26 (m, 2H), 2.17 (s, 3H), 1.88e1.84 (m, 2H) ppm.
2H) ppm. 13C NMR (75 MHz, CDCl3):
d
¼201.4, 192.6, 175.5, 148.3,
139.2, 134.9, 134.5, 134.4, 129.9, 128.8, 123.2, 122.4, 63.9, 55.4, 45.2,
31.2, 27.6 ppm. Isomer 13C NMR (75 MHz, CDCl3):
d¼200.0, 192.9,
Isomer 1H NMR (400 MHz, CDCl3):
7.54e7.50 (m, 3H), 7.29e7.24 (m, 5H), 6.24 (d, J¼11.5 Hz, 1H), 5.42
(d, J¼11.8 Hz, 1H), 3.32e3.31 (m, 1H), 2.79e2.76 (m, 1H), 2.13e2.09
(m, 2H), 1.88 (s, 3H), 1.69e1.67 (m, 2H) ppm. 13C NMR (100 MHz,
d
¼8.04 (d, J¼7.5 Hz, 2H),
175.6, 148.2, 139.7, 136.2, 134.9, 134.2, 129.9, 129.1, 128.8, 123.4,
122.3, 58.1, 48.6, 31.5, 30.6, 30.4, 18.3 ppm. HRMS: calcd for
C21H20N2O5: [M]þ 380.1372; found, 380.1263.
CDCl3):
127.9, 64.7, 55.6, 44.6, 31.5, 27.4, 18.4 ppm. Isomer 13C NMR
(100 MHz, CDCl3):
d
¼202.8, 193.3, 175.4, 137.0, 136.5, 134.3, 129.1, 128.9, 128.3,
4.2.5. 2-((4-Bromophenyl)(2-oxopyrrolidin-1-yl)methyl)-1-
phenylbutane-1,3-dione (3ea). Yield (133.3 mg, 79%). Yellow solid.
d¼201.4, 193.0, 175.4, 137.5, 136.5, 134.1, 129.1,
Mp 118.3e119.5 ꢀC. IR (KBr):
n
¼3432, 2964, 1670, 1421, 1269 cmꢁ1
.
128.7, 128.3, 127.9, 64.6, 49.6, 47.8, 31.6, 27.4, 18.2 ppm. HRMS: calcd
Characterized as a 3:1 diastereomeric mixture. 1H NMR (400 MHz,
for C21H21NO3: [M]þ 335.1521; found, 335.1611.
CDCl3):
d
¼7.96 (d, J¼7.6 Hz, 2H), 7.48e7.41 (m, 3H), 7.36 (d,
J¼8.2 Hz, 2H), 7.16 (d, J¼8.2 Hz, 2H), 6.08 (d, J¼11.7 Hz, 1H), 5.71 (d,
J¼11.7 Hz, 1H), 3.45e3.38 (m, 1H), 3.16e3.10 (m, 1H), 2.34e2.25 (m,
2H), 2.23 (s, 3H), 1.97e1.90 (m, 2H) ppm. Isomer 1H NMR (400 MHz,
4.2.9. 2-((2-Oxopyrrolidin-1-yl)(p-tolyl)methyl)-1-phenylbutane-
1,3-dione (3ia). Yield (94.2 mg, 67%). White solid. Mp
125.6e126.2 ꢀC. IR (KBr):
n
¼3429, 2927, 1678, 1421, 1262,
1086 cmꢁ1. Characterized as a 4:1 diastereomeric mixture. 1H NMR
(400 MHz, CDCl3):
CDCl3):
d
¼8.11 (d, J¼7.9 Hz, 2H), 7.62e7.58 (m, 3H), 7.51e7.41 (m,
4H), 6.33 (d, J¼11.4 Hz, 1H), 5.40 (d, J¼11.4 Hz, 1H), 3.45e3.43 (m,
d
¼7.98 (d, J¼7.6 Hz, 2H), 7.47e7.30 (m, 4H),
1H), 3.30e3.28 (m, 1H), 2.17e2.14 (m, 2H), 1.97 (s, 3H), 1.94e1.90
7.17e7.13 (m, 3H), 7.02 (d, J¼7.9 Hz, 2H), 6.20 (d, J¼11.8 Hz,1H), 5.65
(d, J¼11.8 Hz, 1H), 3.45e3.40 (m, 1H), 3.12e3.08 (m, 1H), 2.34e2.31
(m, 2H), 2.24 (s, 6H), 1.92e1.89 (m, 2H) ppm. Isomer 1H NMR
(m, 2H) ppm. 13C NMR (75 MHz, CDCl3):
d
¼201.9,192.6, 173.3,136.5,
136.1, 134.3, 131.9, 129.4, 128.9, 122.2, 64.3, 58.1, 47.6, 29.7, 18.1 ppm.
Isomer 13C NMR (75 MHz, CDCl3):
d¼200.8, 192.9, 173.3, 136.5,
(400 MHz, CDCl3):
d
¼8.11 (d, J¼7.6 Hz, 2H), 7.60e7.57 (m, 4H),
136.1, 133.9, 132.0, 130.2, 129.4, 128.9, 122.5, 58.1, 48.0, 31.7, 30.9,
30.2, 18.1 ppm. HRMS: calcd for C21H20BrNO3: [M]þ 413.0627;
found, 413.0693.
7.04e7.02 (m, 3H), 6.26 (d, J¼11.6 Hz, 1H), 5.49 (d, J¼11.6 Hz, 1H),
3.39e3.35 (m, 1H), 3.26e3.25 (m, 1H), 2.18e2.14 (m, 2H), 1.96 (s,
6H), 1.71e1.69 (m, 2H) ppm. 13C NMR (75 MHz, CDCl3):
d¼202.7,
192.8, 175.1, 137.8, 136.4, 134.0, 133.7, 129.4, 128.8, 128.7, 127.6, 64.6,
4.2.6. 2-((2-Bromophenyl)(2-oxopyrrolidin-1-yl)methyl)-1-
54.9, 44.2, 31.3, 27.1, 18.1 ppm. Isomer 13C NMR (75 MHz, CDCl3):
phenylbutane-1,3-dione (3fa). Yield (102.5 mg, 63%). Yellow solid.
d
¼201.6, 193.3, 175.1, 138.2, 136.6, 134.2, 133.7, 129.6, 128.7, 128.3,
Mp 130.7e131.5 ꢀC. IR (KBr):
n
¼3246, 2964, 1976, 1688, 1440, 1284,
1171, 994, 762, 685, 534 cmꢁ1. Characterized as a 1:1 diastereomeric
mixture. 1H NMR (400 MHz, CDCl3):
127.6, 64.4, 58.0, 49.4, 47.4, 31.7, 27.1, 21.1, 17.6 ppm. HRMS: calcd for
C22H23NO3: [M]þ 349.1678; found, 349.1759.
d¼8.13 (d, J¼7.8 Hz, 2H), 8.05
(d, J¼7.8 Hz, 2H), 7.94 (d, J¼7.8 Hz, 2H), 7.63e7.49 (m, 6H),
7.44e7.41 (m, 3H), 7.36 (t, J¼7.6 Hz, 1H), 7.15e7.11 (m, 2H), 7.05 (t,
J¼7.6 Hz, 1H), 6.62 (d, J¼11.3 Hz, 1H), 6.27 (d, J¼11.4 Hz, 1H), 6.01 (d,
J¼11.4 Hz,1H), 6.83 (d, J¼11.3 Hz,1H), 3.64e3.60 (m,1H), 3.58e3.52
(m, 1H), 3.51e3.39 (m, 1H), 3.20e3.14 (m, 1H), 2.46e2.44 (m, 2H),
2.29 (s, 3H), 2.12e2.08 (m, 2H), 1.97 (s, 3H), 1.84e1.77 (m, 2H) ppm.
4.2.10. 2-((4-Methoxyphenyl)(2-oxopyrrolidin-1-yl)methyl)-1-
phenylbutane-1,3-dione (3ja). Yield (88.0 mg, 61%). White solid. Mp
81.2e82.2 ꢀC. IR (KBr):
n
¼3436, 2963, 1675, 1426, 1261, 1031,
805 cmꢁ1. Characterized as a 3:1 diastereomeric mixture. 1H NMR
(400 MHz, CDCl3):
d¼7.97 (d, J¼7.6 Hz, 2H), 7.46 (t, J¼7.5 Hz, 3H),
7.15 (d, J¼8.4 Hz, 2H), 6.75 (d, J¼8.4 Hz, 2H), 6.14 (d, J¼11.8 Hz, 1H),
5.66 (d, J¼11.8 Hz, 1H), 3.72 (s, 3H), 3.42e3.35 (m, 1H), 3.15e3.11
(m, 1H), 2.38e2.31 (m, 2H), 2.24 (s, 3H), 1.93e1.89 (m, 2H) ppm.
13C NMR (75 MHz, CDCl3):
d
¼207.3, 206.1, 198.2, 197.8, 180.5, 141.7,
141.3, 139.5, 137.2, 137.1, 136.2, 136.1, 135.4, 134.7, 134.4, 133.9, 132.1,
130.3, 129.6, 129.1, 128.9, 127.7, 127.4, 69.5, 62.8, 60.2, 53.2, 49.8,
36.9, 36.5, 35.5, 32.4, 23.4, 23.3 ppm. HRMS: calcd for C21H20BrNO3:
[M]þ 413.0627; found, 413.0693.
Isomer 1H NMR (400 MHz, CDCl3):
d¼8.11 (d, J¼7.6 Hz, 2H), 7.59 (t,
J¼7.5 Hz, 3H), 7.51 (d, J¼7.5 Hz, 2H), 6.87 (d, J¼7.5 Hz, 2H), 6.25 (d,
J¼11.5 Hz, 1H), 5.46 (d, J¼11.5 Hz, 1H), 3.80 (s, 3H), 3.27e3.24 (m,
1H), 3.87e3.84 (m, 1H), 2.16 (s, 3H), 2.04e2.00 (m, 2H), 1.81e1.77
4.2.7. 2-((4-Fluorophenyl)(2-oxopyrrolidin-1-yl)methyl)-1-
phenylbutane-1,3-dione (3ga). Yield (109.5 mg, 77%). White solid.
(m, 2H) ppm. 13C NMR (100 MHz, CDCl3):
d¼202.8, 193.0, 175.3,
159.4, 136.5, 134.2, 129.8, 129.5, 129.1, 128.9, 114.4, 64.9, 57.9, 55.3,
Mp 106.5e107.1 ꢀC. IR (KBr):
n
¼3438, 2920, 1676, 1507, 1424, 1271,
812, 695 cmꢁ1. Characterized as a 3:1 diastereomeric mixture. 1
NMR (400 MHz, CDCl3):
44.5, 31.6, 27.3, 18.2 ppm. Isomer 13C NMR (100 MHz, CDCl3):
H
d
¼201.8, 193.6, 175.1, 159.7, 136.8, 134.9, 129.5, 128.9, 114.3, 64.6,
d
¼7.94 (d, J¼7.7 Hz, 2H), 7.55e7.41 (m, 4H),
55.1, 49.6, 47.5, 31.9, 30.8, 17.8 ppm. HRMS: calcd for C22H23NO4:
[M]þ 365.1627; found, 365.1701.
7.03 (t, J¼8.5 Hz, 1H), 6.90 (t, J¼8.5 Hz, 2H), 6.08 (d, J¼11.8 Hz, 1H),
5.73 (d, J¼11.8 Hz, 1H), 3.45e3.39 (m, 1H), 3.16e3.10 (m, 1H),
2.36e2.31 (m, 2H), 2.22 (s, 3H), 1.95e1.89 (m, 2H) ppm. Isomer 1H
4.2.11. 2-((3-Methoxyphenyl)(2-oxopyrrolidin-1-yl)methyl)-1-
NMR (400 MHz, CDCl3):
d
¼8.10 (d, J¼7.6 Hz, 2H), 7.58e7.50 (m, 4H),
phenylbutane-1,3-dione (3ka). Yield (99.5 mg, 68%). White solid.
7.26e7.24 (m, 4H), 6.32 (d, J¼11.5 Hz, 1H), 5.42 (d, J¼11.5 Hz, 1H),
Mp 112.5e113.0 ꢀC. IR (KBr):
n
¼3428, 2947, 1673, 1596, 1423, 1272,
1173, 1054, 989, 760 cmꢁ1. Characterized as a 5:1 diastereomeric
mixture. 1H NMR (400 MHz, CDCl3):
3.39e3.37 (m, 1H), 3.31e3.27 (m, 1H), 2.16e2.14 (m, 2H), 1.91 (s,
3H), 1.78e1.70 (m, 2H) ppm. 13C NMR (100 MHz, CDCl3):
d¼197.8,
d¼7.98 (d, J¼7.6 Hz, 2H), 7.59
188.4, 170.9, 159.1, 156.6, 131.8, 129.8, 128.4, 125.8, 124.5, 115.0, 60.1,
(t, J¼7.5 Hz, 2H), 7.54e7.40 (m, 3H), 6.81e6.74 (m, 2H), 6.20 (d,
J¼11.8 Hz, 1H), 5.65 (d, J¼11.8 Hz, 1H), 3.69 (s, 3H), 3.44e3.43 (m,
1H), 3.12e3.10 (m, 1H), 2.35e2.34 (m, 2H), 2.24 (s, 3H), 1.91e1.83
50.7, 40.3, 27.3, 26.9, 13.7 ppm. Isomer 13C NMR (100 MHz, CDCl3):
d
¼196.8, 188.7, 170.9, 159.4, 156.9, 132.0, 129.5, 129.0, 125.0, 124.4,
111.3, 53.6, 45.2, 43.6, 26.3, 25.3, 13.5 ppm. HRMS: calcd for
C21H20FNO3: [M]þ 353.1427; found, 353.1502.
(m, 2H) ppm. Isomer 1H NMR (400 MHz, CDCl3):
d
¼8.11 (d,
J¼7.5 Hz, 2H), 7.29e7.25 (m, 2H), 7.13e7.07 (m, 2H), 6.84e6.81 (m,
1H), 6.74e6.71 (m, 2H), 6.25 (d, J¼11.6 Hz, 1H), 5.52 (d, J¼11.6 Hz,
1H), 4.13e4.10 (m, 1H), 3.81 (s, 3H), 3.36e3.27 (m, 1H), 2.20e2.16
(m, 2H), 2.06e2.02 (m, 2H), 1.99 (s, 3H) ppm. 13C NMR (75 MHz,
4.2.8. 2-((2-Oxopyrrolidin-1-yl)(phenyl)methyl)-1-phenylbutane-
1,3-dione (3ha). Yield (88.6 mg, 68%). White solid. Mp