298
I.A. Khan, A.K. Saxena / Tetrahedron 68 (2012) 294e299
24.42, 23.99; ESI-MS (MþH) 295.1 m/z and HRMS calcd mass for
129.01, 128.57, 128.57, 127.31, 126.44, 49.72, 41.51, 30.75, 28.64,
26.32, 25.80; HRMS calcd mass for C20H22N2O2 322.1681 found
322.1673.
C18H18N2O2 294.1368 found 294.1394.
4.2.10. 4-Nitro-N-(2-oxopiperidin-3-yl)-N-p-tolylbenzamide
(12j). The crude product obtained using condition A is purified
using column chromatography (5% EtOAc/hexane) to give the title
compound 12j (97.0 mg, 78%) as a yellow oil; Rf (10% EtOAc/hexane)
0.35; IR (neat) cmꢁ1 3507, 3335, 1705, 1687, 1475, 1233, 875; 1H
4.2.15. 4-Nitro-N-(2-oxoazocan-3-yl)-N-phenylbenzamide
(12o). The crude product obtained using condition A is purified
using column chromatography (5% EtOAc/hexane) to give the
title compound 12o (56.0 mg, 50%) as a yellow oil; Rf (10%
EtOAc/hexane) 0.30; IR (neat) cmꢁ1 3507, 3335, 1687, 1648,
NMR (300 MHz, CDCl3)
ArH), 7.48e6.92 (4H, m, ArH), 6.31 (1H, s, NH), 4.76e4.13 (1H, m,
CH), 3.48e3.02 (2H, m, NHCH2), 2.92e1.50 (7H, m, CH2CH2,
ArCH3); 13C NMR (75 MHz, CDCl3)
170.89, 170.44, 148.54, 140.12,
d
8.33 (2H, d, J¼7.6, ArH), 8.11 (2H, d, J¼7.6,
14,735, 1236, 873; 1H NMR (300 MHz, CDCl3)
d
8.45e8.24 (2H,
m, ArH), 8.24e8.04 (2H, m, ArH), 7.70e6.66 (5H, m, ArH), 6.17
(1H, s, NH), 4.44 (1H, t, J¼4.6, CH), 3.45 (2H, dd, J¼7.9, 3.9,
NHCH2), 2.54e1.25 (8H, m, 4CH2); 13C NMR (75 MHz, CDCl3)
171.53, 170.89, 148.54, 140.12, 139.31, 129.01, 127.31, 126.44,
a
b
d
a
137.58, 134.71, 129.95, 129.01, 124.67, 123.99, 51.80, 40.81, 24.42,
23.99, 21.12; ESI-MS (MþH) 354.2 m/z and HRMS calcd mass for
C19H19N3O4 353.1375 found 353.1364.
d
123.99, 49.72, 41.51, 30.75, 28.64, 26.32, 25.80; ESI-MS (MþH)
368.6 m/z and HRMS calcd mass for C20H21N3O4 367.1532 found
367.1524.
4.2.11. 2-Methoxy-N-(2-oxopiperidin-3-yl)-N-p-tolylbenzamide
(12k). The crude product obtained using condition A is purified
using column chromatography (5% EtOAc/hexane) to give the title
compound 12k (41.0 mg, 62%) as a dark yellow oil; Rf (15% EtOAc/
hexane) 0.40; IR (neat) cmꢁ1 3527, 3313,1687,1641,1374,1232, 875;
4.2.16. N-(4-Methoxyphenyl)-4-nitro-N-(2-oxoazocan-3-yl)benza-
mide (12p). The crude product obtained using condition A is pu-
rified using column chromatography (5% EtOAc/hexane) to give the
title compound 12p (43.0 mg, 48%) as a yellow oil; Rf (10% EtOAc/
hexane) 0.32; IR (neat) cmꢁ1 3507, 3335, 1705, 1687, 1475, 1233,
1H NMR (300 MHz, CDCl3)
(7H, m, ArH), 6.19 (1H, s, NH), 4.66e4.20 (1H, m, NCH), 3.83 (3H, s,
OCH3), 3.46e3.02 (2H, m, NHCH2), 2.85e2.14 (4H, m, ArCH3,
NCCHH), 2.10e1.48 (3H, m, NHCH2CHH); 13C NMR (75 MHz, CDCl3)
d
7.87 (1H, dd, J¼6.8, 1.6, ArH), 7.69e6.91
875; 1H NMR (300 MHz, CDCl3)
d
8.34 (2H, d, J¼7.6, ArH), 8.12 (2H,
d, J¼7.6, ArH), 7.29 (2H, t, J¼3.7, ArH), 6.95 (2H, d, J¼7.5,ArH), 6.33
d
170.44, 167.93, 156.86, 137.58, 134.71, 132.47, 131.06, 129.95,
(1H, s, NH), 4.44 (1H, t, J¼4.6,
aCH), 3.81 (3H, s, OCH3), 3.46 (2H, t,
125.45, 124.67, 120.70, 113.66, 56.78, 51.80, 40.81, 24.42, 23.99,
21.12; ESI-MS (MþH) 339.1 m/z and HRMS calcd mass for
C20H22N2O3 338.1630 found 338.1621.
J¼6.0, NHCH2), 2.64e1.17 (8H, m, 4CH2); 13C NMR (75 MHz, CDCl3)
d
171.53, 170.89, 156.85, 148.54, 140.12, 132.19, 129.01, 127.40,
123.99, 114.97, 56.03, 49.72, 41.51, 30.75, 28.64, 26.32, 25.80; ESI-
MS (MþH) 398.4 m/z and HRMS calcd mass for C21H23N3O5
397.1637 found 397.1652.
4.2.12. N-(2-Oxoazepan-3-yl)-N-p-tolylbenzamide (12l). The crude
product obtained using condition A is purified using column
chromatography (5% EtOAc/hexane) to give the title compound 12l
(34.0 mg, 48%) as a yellow oil; Rf (10% EtOAc/hexane) 0.42; IR (neat)
cmꢁ1 3537, 3325, 1667, 1455, 1235, 875; 1H NMR (300 MHz, CDCl3)
4.2.17. N-(4-Methoxybenzyl)-4-nitro-N-(2-oxoazocan-3-yl)benza-
mide (12q). The crude product obtained using condition A is
purified using column chromatography (8% EtOAc/hexane) to
give the title compound 12q (35.0 mg, 36%) as a yellow oil; Rf
(10% EtOAc/hexane) 0.34; IR (neat) cmꢁ1 1677, 1653, 1474, 1234,
d
8.05e7.64 (2H, m, ArH), 7.44 (3H, dt, J¼4.2, 1.9, ArH), 7.34e7.03
(4H, m, ArH), 5.02e4.62 (1H, m,
NHCH2), 3.17 (1H, dt, J¼12.6, 5.4,
a
CH), 4.47 (2H, dd, J¼10.3, 5.0,
b
CHH), 2.87e1.93 (5H, m, ArCH3,
875; 1H NMR (300 MHz, CDCl3)
d
8.38 (2H, d, J¼7.6, ArH), 8.14
(2H, d, J¼7.6, ArH), 7.51e7.11 (2H, m, ArH), 6.92 (2H, d, J¼7.6,
ArH), 6.03 (1H, s, NH), 4.64e4.21 (3H, m, CH, AnisylCH2),
b
CHHCH2), 1.90e0.73 (4H, m, CH2CH2); 13C NMR (75 MHz, CDCl3)
d
170.89, 169.46, 137.58, 135.48, 134.71, 130.99, 129.95, 128.57,
a
124.67, 55.32, 42.43, 30.90, 29.87, 24.32, 21.12; ESI-MS (MþH) 323.1
m/z and HRMS calcd mass for C20H22N2O2 322.1681 found
322.1643.
4.07e3.46 (4H, m, NHCHH, OCH3), 3.18 (1H, dt, J¼12.5, 4.6,
NHCHH), 2.61e1.28 (8H, m, 4CH2); 13C NMR (75 MHz, CDCl3)
d
174.62, 170.61, 159.85, 146.84, 141.05, 129.13, 128.11, 127.36,
123.84, 113.80, 56.03, 52.92, 47.89, 41.51, 29.96, 28.64, 26.32,
25.80; ESI-MS (MþH) 412.1 m/z and HRMS calcd mass for
C22H25N3O5 411.1794 found 411.1773.
4.2.13. 2-(Biphenyl-4-yl)-N-(2-oxoazepan-3-yl)-N-p-tolylacetamide
(12m). The crude product obtained using condition A is purified
using column chromatography (5% EtOAc/hexane) to give the title
compound 12m (46.0 mg, 51%) as a yellow oil; Rf (10% EtOAc/
hexane) 0.48; IR (neat) cmꢁ1 3507, 3335, 1705, 1687, 1475, 1233,
4.2.18. N-(3,4-Dimethoxyphenethyl)-4-nitro-N-(2-oxoazocan-3yl)
benzamide (12r). The crude product obtained using condition E
is purified using column chromatography (7% EtOAc/hexane) to
give the title compound 12r (47.0 mg, 42%) as a yellow oil; Rf
(14% EtOAc/hexane) 0.37; IR (neat) cmꢁ1 3507, 3347, 1715, 1689,
875; 1H NMR (300 MHz, CDCl3)
(2H, d, J¼7.6, ArH), 4.63e4.26 (2H, m, NH,
BiphenylCH2), 3.19 (2H, t, J¼4.6, NHCH2), 2.93e2.17 (4H, m, ArCH3,
CHH), 2.15e0.95 (5H, m,
CHH, CH2CH2); 13C NMR (75 MHz,
d
7.94e7.08 (11H, m, ArH), 6.93
CH), 3.92 (2H, s,
a
b
b
1468, 1243, 875; 1H NMR (300 MHz, CDCl3)
d
8.36 (2H, d, J¼7.6,
ArH), 8.09 (2H, d, J¼7.6, ArH), 6.89 (3H, s, ArH), 5.98 (1H, s, NH),
5.07e4.61 (1H, m,
CDCl3) precluded due to lesser concentration; ESI-MS (MþH) 413.2
m/z and HRMS calcd mass for C27H28N2O2 412.2151 found
412.2134.
a
CH), 4.44 (1H, t, J¼7.4, NCHH), 4.13e3.76
(7H, m, NCHH, 2eOCH3), 3.74e3.41 (1H, m, NHCHH), 3.29e2.75
(3H, m, NHCHH, ArCH2), 2.58e1.09 (8H, m, 4CH2); 13C NMR
4.2.14. N-(2-Oxoazocan-3-yl)-N-phenylbenzamide (12n). The crude
product obtained using condition A is purified using column chro-
matography (5% EtOAc/hexane) to give the title compound 12n
(38.0 mg, 54%) as a yellow oil; Rf (10% EtOAc/hexane) 0.40; IR (neat)
cmꢁ1 3507, 3335, 1705, 1687, 1475, 1233, 875; 1H NMR (300 MHz,
(75 MHz, CDCl3) d 174.62, 170.82, 148.92, 148.78, 146.84, 141.05,
133.21, 128.11, 123.84, 122.38, 113.11, 112.80, 56.78, 51.44, 42.97,
41.51, 35.14, 29.96, 28.64, 26.32, 25.80; ESI-MS (MþH) 456.1 m/z
and HRMS calcd mass for C24H29N3O6 455.2056 found
455.2044.
CDCl3) d 8.17e7.67 (2H, m, ArH), 7.64e6.78 (8H, m, ArH), 6.29 (1H, s,
NH), 4.44 (1H, t, J¼4.1,
a
CH), 3.80 (1H, dt, J¼12.5, 4.7, NHCHH), 3.21
4.2.19. N-Allyl-4-nitro-N-(2-oxoazocan-3-yl)benzamide (12s). The
crude product obtained using condition E is purified using column
chromatography (5% EtOAc/hexane) to give the title compound
(1H, dt, J¼12.5, 4.6, NHCHH), 2.56e1.14 (8H, m, 4CH2); 13C NMR
(75 MHz, CDCl3)
d 171.53, 170.89, 139.31, 135.48, 130.99, 129.01,