1592
T. Patonay et al.
116.5 (C-1 (Z)), 117.5 (C-1 (E)), 119.2 (C-80 (Z)), 119.3 (C-80
(E)), 124.8 (C-4a0 (Z)), 125.0 (C-4a0 (E)), 125.2 (C-50 (E)), 128.3
(C-50 (Z)), 130.6 (C-60 (E)), 130.7 (C-60 (Z)), 131.7 (C-70 (E)),
132.1 (C-70 (Z)), 146.7 (C-3 (Z)) 148.4 (C-3 (E)), 155.2 (C-20)
157.0 (C-8a0 (Z)), 157.5 (C-8a0 (E)), 176.7 (C-40). (Found:
C 72.91, H 3.51, N 7.00. C12H7NO2 requires: C 73.09, H 3.58,
N 7.10%.)
6.1, 1H, 2-H). dC ([D6]DMSO) 30.9 (CH3), 70.3 (C-30), 113.1
(C-3), 119.8 (C-10), 122.6 (C-8), 124.3 (C-5), 125.2 (C-4a),
132.7 (C-7), 135.5 (C-6), 141.9 (C-20), 156.0 (C-8a), 157.5
(C-2), 177.3 (C-4). (Found: C 73.19, H 5.97. C14H14O3 requires:
C 73.03, H 6.13%.)
(E)- and (Z)-3-(4-Oxo-4H-1-benzopyran-7-yl)
acrylonitrile 36
Ethyl (E)-3-(4-Oxo-4H-1-benzopyran-6-yl)acrylate 32
Yellow crystalline powder. Yield: 65% (Conditions B, reaction
time: 2.5 h), E:Z ¼ 78:22 (determined from 1H NMR spectrum).
Mp 170.5–1748C. vmax(KBr)/cmꢁ1 2215 (CN), 1658 (C¼O),
1622 (C¼C), 1600, 1556, 1433, 1401, 1348, 1322, 1308, 1148,
966, 856. dH ([D6]DMSO) 6.20 (d, J 12.1, 1H, 2-H (Z)), 6.42
(overlapping ds, 1H, 30-H), 6.77 (d, J 17.0, 1H, 2-H (E)), 7.56–
8.02 (m, 3H, 60,80,3-H), 8.05 (d, J 8.3, 1H, 50-H (E)), 8.13 (d,
J 8.3, 1H, 50-H (Z)), 8.34 (overlapping ds, 1H, 20-H). dC ([D6]
DMSO) 99.4 (C-2 (Z)), 100.8 (C-2 (E)), 112.6 (C-30), 117.9 (C-1
(Z)), 118.2 (C-80 (E)), 118.5 (C-1 (E)), 118.8 (C-80 (Z)), 124.2
(C-60 (E)), 125.2 (C-60 (Z)), 125.3 (C-4a0 (Z)), 125.4 (C-4a0 (E)),
125.9 (C-50 (E)), 126.0 (C-50 (Z)), 139.0 (C-70 (Z)), 139.2 (C-70
(E)), 147.1 (C-3 (Z)), 148.9 (C-3 (E)), 155.8 (C-8a0 (E)), 155.9
(C-8a0 (Z)), 157.3 (C-20), 175.8 (C-40). (Found: C 73.06, H 3.29,
N 7.00. C12H7NO2 requires: C 73.09, H 3.58, N 7.10%.)
White crystalline powder. Yield: 78% (Conditions A, reaction
time: 5.5 h); 92% (Conditions C, reaction time: 25 min). Mp
143.5–1458C. vmax(KBr)/cmꢁ1 1708 (C¼O, ester), 1658, 1637
(C¼O, ketone), 1610, 1484, 1442, 1325, 1284, 1261, 1184, 1171
(C–O–C), 816. dH (CDCl3) 1.35 (t, J 7.0, 3H, OCH2CH3), 4.29
(q, J 7.0, 2H, OCH2CH3), 6.37 (d, J 6.2, 1H, 30-H), 6.53 (d, J
16.0, 1H, 2-H), 7.48 (d, J 7.0, 1H, 80-H), 7.74 (d, J 16.0, 1H,
3-H), 7.82 (dd, J 7.0, 2.0, 1H, 70-H), 7.86 (d, J 6.2, 1H, 20-H),
8.35 (d, J 2.0, 1H, 50-H). dC (CDCl3) 14.2 (OCH2CH3), 60.6
(OCH2CH3), 113.2 (C-30), 119.0 (C-2), 119.8 (C-80), 124.9
(C-4a0), 125.6 (C-50), 131.7 (C-60), 132.5 (C-70), 142.4 (C-3),
155.3 (C-20), 157.0 (C-8a0), 166.4 (C-1), 177.0 (C-40). (Found:
C 68.80, H 4.79. C14H12O4 requires: C 68.85, H 4.95%.)
(E)-3-(4-Oxo-4H-1-benzopyran-6-yl)acrylaldehyde 33
Off-white crystalline powder. Yield: 28% (Conditions A, reac-
tion time: 7 h, conversion: 87%); 10% (Conditions C, reaction
time: 1.5 h). Isolated as a by-product in addition to cross-
coupled product 34. Mp 175–1778C. vmax(KBr)/cmꢁ1 1680
(CHO), 1657 (C¼O), 1627 (C¼C), 1607, 1486, 1447, 1389,
1328, 1254, 1134, 1024, 977, 859, 816. dH (CDCl3) 6.40 (d, J
5.7, 1H, 30-H), 6.78 (dd, J 15.6, 7.5, 1H, 2-H), 7.53–7.58 (m, 2H,
80,3-H), 7.88–7.91 (m, 2H, 20,70-H), 8.38 (d, J 2.7, 1H, 50-H),
9.75 (d, J 7.5, 1H, 1-H). dC (CDCl3) 113.4 (C-30), 119.4 (C-80),
125.1 (C-4a0), 126.9 (C-50), 129.6 (C-2), 131.2 (C-60), 132.3 (C-
70), 150.2 (C-20), 155.4 (C-3), 155.7 (C-8a0), 176.9 (C-40), 193.2
(C-1). (Found: C 72.22, H 3.89. C12H8O3 requires: C 72.00,
H 4.03%.)
Ethyl (E)-3-(4-Oxo-4H-1-benzopyran-7-yl)acrylate 37
Yellow crystalline powder. Yield: 71% (Conditions B, reaction
time: 2.5 h). Mp 103.5–104.58C. vmax(KBr)/cmꢁ1 1706 (C¼O,
ester), 1644 (C¼O, ketone), 1622 (C¼C), 1430, 1316, 1293,
1185 (C–O–C), 816. dH (CDCl3) 1.36 (t, J 7.0, 3H, OCH2CH3),
4.30 (q, J 7.0, 2H, OCH2CH3), 6.35 (d, J 6.3, 1H, 30-H), 6.58 (d, J
16.1, 1H, 2-H), 7.56–7.57 (m, 2H, 60,80-H), 7.71 (d, J 16.1, 1H,
3-H), 7.86 (d, J 6.3, 1H, 20-H), 8.21 (d, J 8.6, 1H, 50-H). dC
(CDCl3) 14.2 (OCH2CH3), 60.9 (OCH2CH3), 113.3 (C-30),
117.8 (C-80), 122.0 (C-2), 124.0 (C-60), 125.4 (C-4a0), 126.4
(C-50), 139.9 (C-70), 142.1 (C-3), 155.5 (C-20), 156.6 (C-8a0),
166.2 (C-1), 176.9 (C-40). (Found: C 69.07, H 5.06. C14H12O4
requires: C 68.85, H 4.95%.)
Ethyl 3-(4-Oxo-4H-1-benzopyran-6-yl)propionate 34
(E)-3-(4-Oxo-4H-1-benzopyran-7-yl)acrylaldehyde 38
Off-white amorphous solid. Yield: 53% (Conditions C, reaction
time: 1.5 h). Mp 70–718C. vmax(KBr)/cmꢁ1 3064, 2980, 1724
(C¼O, ester), 1662 (C¼O, ketone), 1618 (C¼C), 1484, 1452,
1402, 1374, 1322, 1276, 1188 (C–O–C), 1156, 1028 (C–O–C),
856, 826. dH (CDCl3) 1.23 (t, J 7.0, 3H, OCH2CH3), 2.67 (t, J 7.4,
2H, 3-H), 3.05 (t, J 7.4, 2H, 2-H), 4.12 (q, J 7.0, 2H, OCH2CH3),
6.32 (d, J 6.1, 1H, 30-H), 7.39 (d, J 7.9, 1H, 80-H), 7.53 (dd, J 8.4,
2.1, 1H, 70-H), 7.83 (d, J 6.1, 1H, 20-H), 8.02 (d, J 2.1, 1H, 50-H).
dC (CDCl3) 14.1 (OCH2CH3), 30.2 (C-3), 35.5 (C-2), 60.5
(OCH2CH3), 112.7 (C-30), 118.2 (C-80), 124.6 (C-50), 124.7
(C-4a0), 134.3 (C-70), 137.9 (C-60), 155.2 (C-20), 155.2 (C-8a0),
172.3 (C-1), 177.5 (C-1). (Found: C 68.19, H 5.57. C14H14O4
requires: C 68.28, H 5.73%.)
Brownish crystalline powder. Yield: 12% (Conditions C, reac-
tion time: 20 min). Isolated as a by-product in addition to cross-
coupled product 39. Mp 100–1038C. vmax(KBr)/cmꢁ1 2822
(aldehyde C–H), 1680 (CHO), 1660 (C¼O). dH (CDCl3) 6.38 (d,
J 6.0, 1H, 30-H), 6.83 (dd, J 15.7, 7.9, 1H, 2-H), 7.52–7.63 (m,
3H, 70,80,3-H), 7.88 (d, J 6.0, 1H, 20-H), 8.25 (d, J 8.6, 1H, 50-H),
9.78 (d, J 7.9, 1H, 1-H). dC (CDCl3) 112.8 (C-30), 117.9 (C-80),
123.9 (C-60), 126.1 (C-2), 130.8 (C-50), 138.8 (C-4a0), 149.3 (C-
70), 155.4 (C-20), 156.1 (C-8a0), 176.3 (C-40), 192.6 (C-1).
(Found: C 72.15, H 3.87. C12H8O3 requires: C 72.00, H 4.03%.)
Ethyl 3-(4-Oxo-4H-1-benzopyran-7-yl)propionate 39
Yellow oil. Yield: 67% (Conditions C, reaction time: 20 min).
vmax(neat)/cmꢁ1 3076, 2980, 1732 (C¼O, ester), 1652 (C¼O,
ketone), 1626 (C¼C), 1434, 1348, 1312, 1252, 1216 (C–O–C),
1184, 1030 (C–O–C), 822. dH (CDCl3) 1.23 (t, J 6.9, 3H,
OCH2CH3), 2.69 (t, J 7.4, 2H, 2-H), 3.08 (t, J 7.4, 2H, 3-H), 4.13
(q, J 6.9, 2H, OCH2CH3), 6.31 (d, J 6.1, 1H, 30-H), 7.25–7.30 (m,
2H, 60,80-H), 7.82 (d, J 6.1, 1H, 20-H), 8.12 (d, J 9.1, 1H, 50-H).
dC (CDCl3) 14.1 (OCH2CH3), 30.8 (C-3), 34.9 (C-2), 60.6
(OCH2CH3), 112.9 (C-30), 117.4 (C-80), 123.2 (C-4a0), 125.7
(E)-6-(3-Hydroxy-3-methylbut-1-enyl)chromone 35
Off-white crystalline powder. Yield: 74% (Conditions C, reac-
tion time: 25 min). Mp 80–818C. vmax(KBr)/cmꢁ1 3411 (OH),
2969 (CH3), 1632 (C¼O), 1615 (C¼C), 1599, 1482, 1448, 1324,
1274, 1132 (C–OH), 863, 826. dH ([D6]DMSO) 1.32 (s, 6H,
CH3), 4.82 (s, 1H, OH), 6.37 (d, J 6.1, 1H, 3-H), 6.54 (d, J 15.7,
1H, 20-H), 6.66 (d, J 15.7, 1H, 10-H), 7.60 (d, J 8.8, 1H, 8-H),
7.90 (dd, J 8.8, 1.8, 1H, 7-H), 7.99 (d, J 1.8, 1H, 5-H), 8.30 (d, J