(p-Substituted Styryl) Spirobenzopyrans
1353
(m, J ¼ 16.8 Hz, 2H, CH55CH), 3.04 (s, 6H, NMe2). Anal. calcd. for
C17H16N2O4: C, 65.38; H, 5.16; N, 8.97; found: C, 65.42; H, 5.20; N, 8.95.
General Procedure for the Synthesis of the Spirobenzopyrans 6a–i
To a solution of 5b (2.69 g, 10.0 mmol) in anhydrous ethanol (20 mL) and
THF (10 mL), Fisher’s base (3.74 g, 20.0 mmol) was added, and the
reaction was heated at reflux for 8 h. The solvent was evaporated under
reduced pressure, and the crude residue was purified by column chromato-
graphy, eluting with 1:1 EtOAc–petroleum ether (bp 60–808C) to give the
spirobenzopyran 6b (3.21 g, 72%).
Data
6b. Yield: 72%, mp 113–1158C. IR (KBr): 3010, 2960, 2930, 1660, 1610,
1
1490, 1272, 1014, 1320, 1530, 1355, 972, 913, 860, 813, 735 cm21. H
NMR (d6-acetone): d 7.75 (s, 1H, 70-H), 6.48–7.56 (m, 11H, 50-H, 4-7-H,
a-d-H), 5.80–6.47 (d, J ¼ 10.5 Hz, 2H, 30-H and 40-H), 3.13 (s, 3H,
N-CH3), 2.35 (s, 3H, Ar-CH3), 1.23 (s, 3H, 3-CH3), 1.07 (s, 3-CH3). m/z
(FAB): 453 (M þ H). Anal. calcd. for C29H28N2O3: C, 76.97; H, 6.24; N,
6.19; found: C, 76.79; H, 6.26; N, 6.14.
6d. Yield: 54%, mp 134–1368C. IR (KBr): 3011, 2931, 2815, 1638, 1614, 1483,
1382, 1285, 1073, 978 cm21. 1H NMR (d6-acetone): d 7.89 (d, J ¼ 1.9 Hz, 1H,
70-H), 6.52–7.72 (m, 11H, 50-H, 4-7-H, a-d-H), 5.83–6.46 (dd, J ¼ 10.8 Hz,
2H, 30-H and 40-H), 3.25 (s, 3H, N-CH3), 1.13 (s, 3H, 3-CH3), 0.96 (s, 3H,
3-CH3). m/z (FAB): 443 (M þ H). Anal. calcd. for C27H23FN2O3: C, 73.29;
H, 5.24; N, 6.33; found: C, 73.42; H, 5.27; N, 6.25.
6g. Yield: 71%, mp 178–1808C. IR (KBr): 3011, 2942, 2820, 2221, 1638,
1
1600, 1478, 1293, 1015, 981, 931, 734 cm21. H NMR (d6-acetone): d 7.84
(s, 1H, 70-H), 6.53–7.48(m, 11H, 50-H, 4-7-H, a-d-H), 5.84–6.50 (dd,
J ¼ 10.4 Hz, 2H, 30-H, 40-H), 3.12 (s, 3H, N-CH3), 1.24 (s, 3H, 3-CH3),
1.09 (s, 3H, 3-CH3). m/z (FAB): 460(M þ H). Anal. calcd. for
C28H23N3O3: C, 74.82; H, 5.16; N, 9.35; found: C, 74.87; H, 5.21; N, 9.37.
6i. Yield: 64%, mp 163–1658C. IR (KBr): 3021, 2935, 2821, 1644, 1598,
1478, 1382, 1285, 1019, 977, 914, 735, 879, 811 cm21 1H NMR (d6-
.
acetone): d 7.63 (s, 1H, 70-H), 6.38–7.34 (m, 11H, 50-H, 4-7-H, a-d-H),
5.94–6.82 (dd, J ¼ 10.1 Hz, 2H, 30-H, 40-H), 3.36 (s, 6H, NMe2), 3.16
(s, 3H, N-CH3), 1.25 (s, 3H, 3-CH3), 0.98 (s, 3H, 3-CH3). m/z (FAB): 468
(M þ H). Anal. calcd. for C29H29N3O3: C, 74.50; H, 6.25; N, 8.99; found:
C, 74.21; H, 6.24; N, 8.93.