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HETEROCYCLES, Vol. 92, No. 4, 2016
6,8-Di(tert-butyl)-4-phenyl-2H-chromene (5h): Yellow oil; 1H NMR (300 MHz, CDCl3): δ = 7.36 (s,
5H), 7.23 (s, 1H), 6.92 (s, 1H), 5.87 (t, J = 3.9 Hz, 1H), 4.73 (d, J = 3.9 Hz, 2H), 1.42 (s, 9H), 1.21 (s,
9H); 13C NMR (75 MHz, CDCl3): δ = 151.0, 142.7, 139.1, 138.3, 137.1, 128.7, 128.2, 127.6, 124.0, 123.7,
121.1, 119.6, 64.0, 34.8, 34.4, 31.5, 30.0; IR (KBr): υmax = 1654, 1611, 1503, 1449, 1400 cm–1; HRMS
m/z: calcd for C23H28O [M]+ 320.2140; found 320.2146.
1
8-(tert-Butyl)-6-methyl-4-phenyl-2H-chromene (5i): Yellow oil; H NMR (300 MHz, CDCl3): δ =
7.33-7.31 (m, 5H), 6.99(d, J = 1.8 Hz, 1H), 6.69(d, J = 1.5 Hz, 1H), 5.81 (t, J = 3.9Hz, 1H), 4.67 (d, J =
3.9 Hz, 2H), 2.17 (s, 3H), 1.40 (s, 9H); 13C NMR (75 MHz, CDCl3): δ = 151.2, 139.1. 138.1, 137.9, 129.6,
128.8, 128.6, 128.4, 127.7, 127.5, 124.9, 124.5, 120.1, 64.1, 34.6, 30.0, 21.2; IR (KBr): υmax = 1653, 1612,
1452, 1401 cm–1; HRMS m/z: calcd for C20H22O [M]+ 278.1671; found 278.1679.
1
8-Isopropyl-5-methyl-4-phenyl-2H-chromene (5j): Yellow oil; H NMR (300 MHz, CDCl3): δ =
7.30-7.20 (m, 5H), 7.05 (d, J = 7.8 Hz, 1H), 6.70 (d, J = 8.1 Hz, 1H), 5.93 (t, J = 4.5 Hz, 1H), 4.53 (d, J =
4.8 Hz, 2H), 3.36-3.23 (m, 1H), 1.71 (s, 3H), 1.25 (d, J = 6.9 Hz, 6H); 13C NMR (75 MHz, CDCl3): δ
=153.6, 141.6, 139.1, 133.9, 133.1, 128.4, 127.6, 127.2, 125.8, 124.5, 123.6, 122.6, 64.2, 27.2, 22.9, 22.5;
IR (KBr): υmax = 1654, 1613, 1453, 1401, 1168, 1083 cm–1; HRMS m/z: calcd for C19H20O [M]+
264.1514; found 264.1505.
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1
6-Methoxy-2H-chromene (5k) : Colorless oil; H NMR (300 MHz, CDCl3): δ = 6.76-6.61 (m, 2H),
6.54 (d, J = 2.4 Hz, 1H), 6.40 (d, J = 9.3 Hz, 1H), 5.81 (dt, J = 9.3, 4.2 Hz, 1H), 4.76 (dd, J = 4.2, 2.4 Hz,
2H), 3.75 (s, 3H). IR (NaCl): υmax = 2981, 2826, 1474, 1265, 1210, 1150 cm–1; HRMS m/z: calcd for
C10H10O2 [M]+ 162.0681; found 162.0670.
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1
4-(3’,5’-Dimethoxyphenyl)-6-methyl-2H-chromene (5l) : Yellow oil; H NMR (300 MHz, CDCl3):
δ = 6.85 (d, J = 8.2 Hz, 1H), 6.80 (s, 1H), 6.74 (d, J = 8.0 Hz, 1H), 6.41 (s, 3H), 5.71 (t, J = 3.9 Hz, 1H),
4.70 (d, J = 4.0 Hz, 2H), 3.71 (s, 6H), 2.11 (s, 3H); IR (neat): υmax = 1606, 1490, 1454, 1420, 1351, 1220,
1204, 1152 cm–1; HRMS (APCI) m/z: calcd for C18H19O3 [M+H]+ 283.1334; found 283.1325.
1
4-(4’-Methoxy-2’-nitrophenyl)-6-methyl-2H-chromene (5m)20: Brown oil; H NMR (300 MHz,
CDCl3): δ = 7.50 (d, J = 2.7 Hz, 1H), 7.27 (d, J = 8.7 Hz, 1H), 7.16 (dd, J = 8.6 Hz, 2.7 Hz, 1H), 6.93 (d,
J = 8.1 Hz, 1H), 6.76 (d, J = 8.1 Hz, 1H), 6.37 (s, 1H), 5.66 (t, J = 3.9 Hz, 1H), 4.81 (m, 2H), 3.90 (s, 3H),
2.11 (s, 3H); IR (neat): υmax = 1622, 1530, 1490, 1341, 1269, 1224, 1125 cm–1; HRMS (ESI) m/z: calcd
for C17H15NNaO4 [M+Na]+ 320.0899; found 320.0889.
1
4-(4-Fluorophenyl)-6-methyl-2H-chromene (5n)20: Yellow oil; H NMR (300 MHz, CDCl3): δ =
7.40-7.28 (m, 2H), 7.15-7.11 (t, J = 8.7 Hz, 2H), 7.03-6.70 (dd, J = 8.1, 1.8 Hz, 1H), 6.86-6.81 (d, J = 8.1
Hz, 1H), 6.76 (d, J = 1.8 Hz, 1H), 5.77 (t, J = 4.2 Hz, 1H), 4.80 (d, J = 4.2 Hz, 2H), 2.20 (s, 3H); IR
(neat): υmax = 2836, 1731, 1509, 1481, 1346, 1297, 1173 cm–1; HRMS (APCI) m/z: calcd for C16H14FO