R. Ramesh et al. / Tetrahedron 63 (2007) 9153–9162
9161
(t, J¼2.4, 2H), 4.23–4.26 (m, 1H), 4.16–4.19 (m, 1H); 13C
NMR (75 MHz, CDCl3): d 155.7, 141.3, 134.1, 132.0,
129.8, 128.2, 82.3, 67.1; high resolution ESMS (m/z) calcu-
lated for C10H835ClNO2+Na: 232.0141, observed: 232.0140.
CDCl3): d 7.26–7.34 (m, 5H), 4.88 (t, J¼2.4, 2H), 4.65 (s,
2H), 4.13–4.16 (m, 1H), 4.06–4.08 (m, 1H); 13C NMR
(75 MHz, CDCl3): d 157.4, 140.3, 134.9, 128.6, 127.7,
127.2, 81.5, 66.7, 45.1; high resolution ESMS (m/z) calcu-
lated for C11H11NO2+Na: 212.0688, observed: 212.0685.
4.4.7. Compound 2g. Pale yellow solid; yield: 96%; melting
1
point: 117 ꢀC; FTIR (Neat): 1768 (s); H NMR (300 MHz,
4.4.14. Compound 2n. Pale yellow solid; yield: 96%; melt-
ing point: 66 ꢀC; FTIR (Neat): 1767 (s); 1H NMR (300 MHz,
CDCl3): d 7.46 (d, J¼8.4, 2H), 7.18 (d, J¼8.4, 2H), 4.90 (t,
J¼2.4, 2H), 4.60 (s, 2H), 4.09–4.13 (m, 2H); 13C NMR
(75 MHz, CDCl3): d 156.5, 140.0, 133.9, 131.6, 128.9,
121.5, 81.5, 66.7, 44.4; high resolution ESMS (m/z) calcu-
lated for C11H1079BrNO2+Na: 289.9793, observed:
289.9801.
CDCl3): d 7.33–7.47 (m, 3H), 7.25–7.31 (m, 1H), 5.05 (t,
J¼2.4, 2H), 4.27–4.30 (m, 1H), 4.19–4.22 (m, 1H); 13C
NMR (75 MHz, CDCl3): d 154.6, 141.0, 134.9, 134.6,
130.5, 128.5, 127.1, 125.0, 82.5, 67.1; high resolution
ESMS (m/z) calculated for C10H835ClNO2+Na: 232.0141,
observed: 232.0137.
4.4.8. Compound 2h. White solid; yield: 97%; melting
1
point: 70 ꢀC; FTIR (Neat): 1769 (s); H NMR (300 MHz,
4.4.15. Compound 2o. White gummy solid; yield: 76%;
FTIR (Neat): 1765 (s); 1H NMR (300 MHz, CDCl3):
d 4.85 (t, J¼2.4, 2H), 4.17–4.19 (m, 1H), 4.08–4.11 (m,
1H), 3.45 (t, J¼7.2, 2H), 1.61 (q, J¼7.2, 2H), 1.26 (br s,
18H), 0.88 (t, J¼6.6, 3H); 13C NMR (75 MHz, CDCl3):
d 157.1, 140.9, 79.8, 66.6, 52.1, 41.3, 36.3, 31.7, 29.5,
29.4, 29.2, 29.1, 26.6, 26.2, 22.5, 13.9; high resolution
ESMS (m/z) calculated for C16H29NO2+Na: 290.2096,
observed: 290.2103.
CDCl3): d 7.43–7.50 (m, 1H), 7.08–7.19 (m, 3H), 5.05 (t,
J¼2.4, 2H), 4.311–4.33 (m, 1H), 4.19–4.22 (m, 1H); 13C
NMR (75 MHz, CDCl3): d 162.8 (d, JC–F¼247), 155.5,
141.0, 134.8 (d, JC–F¼10), 130.7 (d, JC–F¼9), 122.5 (d,
JC–F¼4), 115.3 (d, JC–F¼20), 114.3 (d, JC–F¼23), 82.5,
67.1; high resolution ESMS (m/z) calculated for
C10H8FNO2+Na: 216.0437, observed: 216.0441.
4.4.9. Compound 2i. Pale yellow solid; yield: 95%; melting
1
point: 85 ꢀC; FTIR (Neat): 1770 (s); H NMR (300 MHz,
4.4.16. Compound 2p. Colorless oil; yield: 68%; FTIR
(Neat): 1765 (s); H NMR (300 MHz, CDCl3): d 4.86 (t,
1
CDCl3): d 7.36–7.39 (m, 1H), 7.23–7.31 (m, 2H), 5.124
(q, J¼2.7, 2H), 4.12–4.15 (m, 1H), 3.81–3.84 (m, 1H),
2.27 (s, 3H); 13C NMR (75 MHz, CDCl3): d 155.0, 139.7,
139.5, 133.6, 130.3, 129.5, 129.3, 128.0, 81.9, 67.5,
17.7; high resolution ESMS (m/z) calculated for
C11H1035ClNO2+Na: 246.0298, observed: 246.0300.
J¼2.4, 2H), 4.13–4.15 (m, 1H), 4.05–4.07 (m, 1H), 3.53
(t, J¼7.2, 2H), 1.56–1.68 (m, 2H), 1.30–1.43 (m, 2H),
0.95 (t, J¼7.2, 3H); 13C NMR (75 MHz, CDCl3): d 156.1,
140.3, 81.5, 66.7, 41.4, 31.1, 19.8, 13.6; high resolution
ESMS (m/z) calculated for C8H13NO2+Na: 178.0844,
observed: 178.0851.
4.4.10. Compound 2j. Pale yellow solid; yield: 96%; melt-
ing point: 116 ꢀC; FTIR (Neat): 1765 (s); 1H NMR (300 Hz,
CDCl3): d 7.91–7.99 (m, 2H), 7.71–7.74 (m, 1H), 7.46–7.59
(m, 4H), 5.12–5.26 (m, 2H), 4.10–4.12 (m, 1H), 3.81–3.84
(m, 1H); 13C NMR (75 MHz, CDCl3): d 156.3, 142.3,
134.6, 129.8, 129.6, 129.5, 128.5, 127.1, 126.8, 126.6,
125.7, 122.2, 82.8, 67.4; high resolution ESMS (m/z) calcu-
lated for C14H11NO2+Na: 248.0688, observed: 248.0691.
4.4.17. Compound 4. White solid; yield: 91%; melting
point: 71 ꢀC; FTIR (Neat): 3302 (s), 2129 (w), 1763 (s),
1
1750 (s); H NMR (300 MHz, CDCl3): d 7.36 (d, J¼8.4,
2H), 7.29 (d, J¼8.4, 2H), 5.05 (t, J¼2.4, 2H), 4.72 (d,
J¼2.4, 2H), 4.39 (t, J¼7.2, 2H), 4.22–4.25 (m, 1H), 4.14–
4.16 (m, 1H), 3.04 (t, J¼7.2, 2H), 2.55 (t, J¼2.4, 1H); 13C
NMR (75 MHz, CDCl3): d 156.0, 154.3, 141.6, 137.5,
132.1, 130.1, 127.0, 82.0, 76.8, 75.7, 68.3, 67.1, 55.1,
34.5; high resolution ESMS (m/z) calculated for
C16H15NO5+Na: 324.0848, observed: 324.0852.
4.4.11. Compound 2k. Yellow solid; yield: 92%; melting
1
point: 47 ꢀC; FTIR (Neat): 1769 (s); H NMR (300 MHz,
CDCl3): d 7.79 (d, J¼8.1, 2H), 7.55 (d, J¼8.1, 2H), 5.08
(br s, 2H), 4.38–4.42 (m, 1H), 4.27–4.30 (m, 1H); 13C
NMR (75 MHz, CDCl3): d 155.1, 140.2, 137.8, 133.4,
127.1, 117.9, 111.7, 83.1, 67.2; high resolution ESMS
(m/z) calculated for C11H8N2O2+Na: 223.0484, observed:
223.0480.
4.4.18. Compound 6a. Colorless crystalline solid; yield:
98%; melting point: 88 ꢀC; FTIR (Neat): 1764 (s); 1H
NMR (300 MHz, CDCl3): d 7.26–7.50 (m, 5H), 5.22–5.29
(m, 1H), 4.19 (t, J¼2.7, 1H), 4.08 (t, J¼2.7, 1H), 1.61 (d,
J¼6, 3H); 13C NMR (75 MHz, CDCl3): d 155.2, 147.5,
133.8, 129.5, 128.2, 126.9, 81.8, 74.9, 21.1; high resolution
ESMS (m/z) calculated for C11H11NO2+Na: 212.0688,
observed: 212.0688.
4.4.12. Compound 2l. Colorless gummy solid; yield: 90%;
FTIR (Neat): 3400 (br), 1763 (s); 1H NMR (300 MHz,
CDCl3): d 7.34 (d, J¼8.4, 2H), 7.27 (d, J¼8.4, 2H), 5.04
(t, J¼2.4, 2H), 4.21–4.24 (m, 1H), 4.13–4.16 (m, 1H),
3.84 (t, J¼6.6, 2H), 2.88 (t, J¼6.6, 2H), 1.97 (br s, 1H);
13C NMR (75 MHz, CDCl3): d 156.1, 141.7, 139.2, 131.7,
130.2, 126.9, 82.0, 67.1, 63.2, 38.6; high resolution ESMS
(m/z) calculated for C12H13NO3+Na: 242.0793, observed:
242.0795.
4.4.19. Compound 6b. Colorless crystalline solid; yield:
96% (mixture of two rotamers); melting point: 106 ꢀC;
FTIR (Neat): 1769 (s); 1H NMR (300 MHz, CDCl3):
d 7.90–7.98 (m, 2H), 7.44–7.75 (m, 5H), 5.33–5.47 (m,
1H), 4.03–4.06 (m, 1H), 3.76–3.79 (m, 1H), 1.74 and 1.68
(2d, J¼6.6, 3H); 13C NMR (75 MHz, CDCl3): d 155.4,
148.1, 148.0, 134.5, 129.8, 129.7, 129.6, 129.4, 128.55,
128.50, 127.1, 127.0, 126.8, 126.5, 125.6, 125.5, 122.2,
121.9, 82.6, 82.5, 75.4, 75.2, 21.7, 20.9; high resolution
4.4.13. Compound 2m. Pale yellow solid; yield: 96%; melt-
ing point: 50 ꢀC; FTIR (Neat): 1765 (s); 1H NMR (300 MHz,