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Chandrasekaran Praveen et al.
for C16H11NO4: C, 68.32; H, 3.94; N, 4.98%. Found: C, Anal. Calcd for C16H12O3: C, 76.18; H, 4.79%. Found:
68.20; H, 3.97; N, 5.02%.
C, 76.30; H, 4.75%.
2.2h 3-(4-Methoxyphenyl)-5-nitro-1H-isochromen-1-
one (2h): Yellow solid: mp 238–240◦C (lit.29 mp
241–242◦C); IR (KBr): 1350, 1517, 1625, 1732 cm−1;
1H NMR (500 MHz, CDCl3): δH 3.89 (s, 3H); 6.97 (d,
2H, J = 9.1 Hz), 7.55 (t, 1H, J = 8.4 Hz); 7.77 (s,
1H); 7.90 (d, 2H, J = 9.1 Hz); 8.48 (dd, 1H, J1 = 8.4,
J2 = 1.3 Hz); 8.61 (dd, 1H, J1 = 8.4, J2 = 1.3 Hz).
13C NMR (125 MHz, CDCl3): δC 55.8, 102.2, 114.0,
122.3, 126.0, 127.1, 128.5, 129.5, 131.4, 136.7, 143.9,
149.9, 161.4, 164.6. MS (EI): m/z = 297 [M+]. Anal.
Calcd for C16H11NO5: C, 64.65; H, 3.73; N, 4.71%.
Found: C, 64.50; H, 3.75; N, 4.77%.
2.2l 3-Ethyl-6-methoxy-1H-isochromen-1-one (2l):
Colourless solid; mp 90–92◦C (lit.33 mp 93–95◦C); IR
1
(KBr): 3085, 2992, 1728, 1647, 1605, 1155 cm−1. H
NMR (500 MHz, CDCl3): δH1.33 (t, 3H, J = 7.6 Hz);
2.61 (q, 2H, J = 7.6 Hz); 3.95 (s, 3H); 6.25 (s, 1H);
6.79 (d, 1H, J = 2.6 Hz); 7.03 (dd, 1H, J1 = 8.6, J2 =
2.6 Hz); 8.22 (d, 1H, J = 8.6 Hz).13C NMR (125 MHz,
CDCl3): δC 11.5, 27.0, 55.9, 102.5, 107.5, 113.6, 116.4,
132.1, 140.2, 160.5, 163.2, 165.2. MS (EI): m/z = 204
[M+]. Anal. Calcd for C12H12O3: C, 70.57; H, 5.92%.
Found: C, 70.30; H, 5.98%.
2.2m 6-Methoxy-3-methyl-1H-isochromen-1-one (2m):
Colourless solid; mp 85–87◦C (lit.34 mp 86–88◦C); IR
2.2i 6-Methoxy-3-phenyl-1H-isochromen-1-one (2i):
Colourless solid; mp 135–137◦C (lit.30 136.5–
137.0◦C); IR (KBr): 1732, 1607, 1519, 720 cm−1.1H
NMR (500 MHz, CDCl3): δH 3.94 (s, 3H); 6.90 (d,
1H, J = 2.6 Hz); 6.92 (s, 1H); 7.05 (dd, 1H, J = 2.6,
8.6 Hz); 7.43–7.48 (m, 3H); 7.85 (dd, 2H, J = 1.3,
8.6 Hz); 8.25 (d, 1H, J = 8.6 Hz).13C NMR (125 MHz,
CDCl3): δC 56.5, 101.9, 108.9, 109.9, 118.0, 125.0,
125.7, 128.9, 129.3, 130.5, 131.6, 136.7, 141.2, 155.1,
159.9, 162.5. MS (EI): m/z = 252 [M+]. Anal. Calcd
for C16H12O3: C, 76.18; H, 4.79%. Found: C, 75.99; H,
4.84%.
1
(KBr): 3075, 2998, 1725, 1650, 1614, 1144 cm−1. H
NMR (500 MHz, CDCl3): δH 2.32 (s, 3H), 3.95 (s, 3H),
6.24 (s, 1H), 6.76 (d, 1H,J = 2.6 Hz), 7.02 (1H, dd,
J1 = 8.6, J2 = 2.6 Hz, 1H), 8.20 (d, 1H, J = 8.6 Hz,
1H); 13C NMR (125 MHz, CDCl3): δC 20.1, 56.1,
104.1, 107.3, 113.4, 116.2, 132.1, 140.3, 155.5, 163.1,
165.0. MS (EI): m/z = 190 [M+]. Anal. Calcd for
C11H10O3: C, 69.46; H, 5.30%. Found: C, 69.60; H,
5.26%.
2.2n 8-Fluoro-3-ethyl-1H-isochromen-1-one33 (2n):
Colourless oil; IR (neat): 3083, 2973, 1743, 1661,
1614 cm−1; 1H NMR (500 MHz, CDCl3): δH 1.30 (t, 3H,
J = 7.6 Hz); 2.59 (qd, 2H, J1 = 7.6, J2 = 1.3 Hz); 6.25
(t, 1H, J = 1.3 Hz); 7.05–7.17 (m, 2H); 7.60–7.72 (m,
1H); 13C NMR (125 MHz, CDCl3): δC 11.4, 27.1, 102.0
(d, JC−F = 3.1 Hz), 109.5 (d, JC−F = 7.1 Hz), 114.9
(d, JC−F = 21.0 Hz), 121.5 (d, JC−F = 4.1 Hz),136.7
(d, JC−F = 10.0 Hz), 140.5, 158.9 (d, JC−F = 5.6 Hz),
161.2, 163.1 (d, JC−F = 266.1 Hz). MS (EI): m/z = 192
[M+]. Anal. Calcd for C11H9FO2: C, 68.74; H, 4.72%.
Found: C, 68.90; H, 4.66%.
2.2j 6-Methoxy-3-(4-methoxyphenyl)-1H-isochromen-
1-one (2j): Colourless solid; mp 144–146◦C (lit.31
mp 145–147◦C); IR (KBr): 1737, 1605, 1514, cm−1.
1H NMR (500 MHz, CDCl3): δH 3.87 (s, 3H); 3.93 (s,
3H); 6.75 (s, 1H); 6.83 (d, 1H, J = 2.6 Hz); 6.90–7.00
(m, 2H); 7.02 (dd, 1H, J1 = 8.6, J2 = 2.6 Hz); 7.75–
7.88 (m, 2H); 8.20 (d, 1H, J = 8.8 Hz). 13C NMR
(125 MHz, CDCl3): δC 55.4, 55.5, 100.1, 107.4, 113.3,
114.1, 114.2, 116.0, 124.4, 126.7, 126.8, 131.7, 140.0,
154.1, 161.0, 162.1, 164.3. MS (EI): m/z = 282 [M+].
Anal. calcd for C17H14O4: C, 72.33; H, 5.00%. Found:
C, 72.45; H, 4.97%.
2.2o 3-Phenyl-1H-benzo[g]isochromen-1-one (2o):
Brown solid; mp 182–183◦C; (lit.35 mp 180.5–181◦C);
IR (KBr): 1730, 1629 cm−1. 1H NMR (500 MHz,
CDCl3): δH 7.06 (s, 1H); 7.40–7.50 (m, 3H); 7.56 (t,
1H, J = 7.6 Hz); 7.67 (t, 1H, J = 7.6 Hz); 7.91–7.92
(m, 4H); 8.02 (d, 1H, J = 8.3 Hz); 8.93 (s, 1H). 13C
NMR (125 MHz, CDCl3): δC 101.9, 119.0, 124.3,
125.1, 126.7, 127.7, 128.8, 129.4, 129.8, 129.8, 132.0,
132.1, 132.2, 132.4, 136.6, 152.0, 162.6. MS (EI):
m/z = 272 [M+]. Anal. Calcd for C19H12O2: C, 83.81;
H, 4.44%. Found: C, 83.45; H, 4.57%.
2.2k 8-Methoxy-3-phenyl-1H-isochromen-1-one (2k):
Yellow solid; mp 142–144◦C (lit.32 mp 143–145◦C);
IR (KBr): 1723, 1569, 1480 cm−1. 1H NMR (500 MHz,
CDCl3): δH 4.02 (s, 3H); 6.85 (s, 1H); 6.95 (d, 1H,
J = 8.0 Hz); 7.05 (d, 1H, J = 8.1 Hz); 7.40–7.54 (m,
3H); 7.65 (t, 1H, J = 8.0 Hz); 7.82–7.95 (m, 2H). 13C
NMR (125 MHz, CDCl3): δC 56.4, 101.7, 109.1, 109.9,
118.1, 125.2, 125.3, 128.6, 128.7, 129.8, 131.6, 135.6,
140.5, 153.8, 159.0, 161.7. MS (EI): m/z = 252 [M+].