PAPER
CAN-Mediated Oxidative Addition
2469
Isopropyl 4-Hydroxy-2-isopropoxy-5-phenylfuran-3-carboxy-
late (3e)
HRMS (EI): m/z [M]+ calcd for C16H16O2: 240.1184; found:
240.1180.
Yellow oil; yield: 170 mg (56%).
6,6-Dimethyl-2-naphthalen-1-yl-6,7-dihydrobenzofuran-4(5H)-
one (6b)
White solid; mp 171–173 °C; yield: 120 mg (41%).
IR (KBr): 3056, 2961, 2876, 1685, 1444 cm–1.
1H NMR (300 MHz, CDCl3): d = 8.32 (d, J = 6.8 Hz, 1 H), 7.89–
7.83 (m, 2 H), 7.72 (d, J = 7 Hz, 1 H), 7.57–7.47 (m, 3 H), 6.98 (s,
1 H), 2.88 (s, 2 H), 2.44 (s, 2 H), 1.22 (s, 6 H).
13C NMR (75 MHz, CDCl3): d = 193.07, 165.61, 154.02, 134.08,
130.41, 129.25, 128.67, 128.25, 127.85, 127.6, 127.61, 126.86,
126.65, 126.45, 126.11, 125.22, 125.17, 122.71, 121.77, 105.42,
52.21, 37.76, 37.72, 35.30, 28.81.
IR (neat): 3459, 2982, 1733, 1675, 1598, 1449 cm–1.
1H NMR (500 MHz, CDCl3): d = 8.09–8.07 (m, 1 H), 7.98–7.96 (m,
1 H), 7.78 (s, 1 H), 7.61–7.57 (m, 2 H), 7.52–7.28 (m, 1 H), 5.29–
5.11 (m, 2 H), 1.35–1.18 (m, 12 H).
13C NMR (125 MHz, CDCl3): d = 196.26, 188.80, 166.61, 163.82,
162.30, 137.23, 136.23, 134.44, 133.95, 128.94, 128.61, 70.12,
69.27, 21.65, 21.63, 21.48, 21.40.
HRMS (EI): m/z [M]+ calcd for C17H20O5: 304.1311; found:
304.1315.
(2-Ethoxy-4-hydroxy-5-phenylfuran-3-yl)phenylmethanone
(3f)
HRMS (EI): m/z [M]+ calcd for C20H18O2: 290.1340; found:
Yellow oil; yield: 250 mg (81%).
290.1342.
IR (neat): 3319, 2960, 1723, 1682, 1598, 1450 cm–1.
6,6-Dimethyl-2-naphthalen-2-yl-6,7-dihydrobenzofuran-4(5H)-
one (6c)
White solid; mp 137–139 °C; yield: 122 mg (42%).
IR (KBr): 2962, 1681, 1452, 1357, 1216 cm–1.
1H NMR (300 MHz, CDCl3): d = 8.15 (s, 1 H), 7.88–7.84 (m, 3 H),
7.72 (d, J = 8.5 Hz, 1 H), 7.51–7.49 (m, 2 H), 7.01 (s, 1 H), 2.87 (s,
2 H), 2.43 (s, 2 H), 1.20 (s, 6 H).
13C NMR (75 MHz, CDCl3): d = 193.62, 171.49, 165.91, 154.67,
133.39, 132.95, 128.62, 128.21, 127.81, 127.14, 126.65, 126.28,
122.55, 122.05, 121.88, 101.41, 52.03, 37.57, 35.32, 28.72.
1H NMR (500 MHz, CDCl3): d = 8.05–8.03 (m, 2 H), 7.88–7.87 (m,
1 H), 7.82–7.79 (m, 1 H), 7.54–7.49 (m, 2 H), 7.48 (s, 1 H), 7.40–
7.36 (m, 4 H), 4.19 (q, J = 18 Hz, 2 H), 1.14 (t, J = 15 Hz, 3 H).
13C NMR (125 MHz, CDCl3): d = 193.26, 188.29, 172.13, 163.72,
145.00, 136.37, 134.25, 133.81, 133.55, 130.35, 129.72, 129.56,
129.03, 128.95, 128.78, 128.68, 128.58, 62.48, 14.06.
HRMS (EI): m/z [M]+ calcd for C19H16O4: 308.1049; found:
308.1045.
1-(2-Ethoxy-4-hydroxy-5-phenylfuran-3-yl)ethanone (3g)
Yellow oil; yield: 189 mg (77%).
HRMS (EI): m/z [M]+ calcd for C20H18O2: 290.1340; found:
290.1341.
IR (neat): 3432, 2957, 1731, 1668, 1597, 1450 cm–1.
1H NMR (500 MHz, CDCl3): d = 7.90–7.85 (m, 1 H), 7.54–7.52
(m, 1 H), 7.44–7.39 (m, 4 H), 4.21–4.11 (m, 2 H), 2.36 (s, 3 H), 1.28
(t, J = 15 Hz, 3 H).
2-Biphenyl-4-yl-6,6-dimethyl-6,7-dihydrobenzofuran-4(5H)-
one (6d)
White solid; mp 170–172 °C; yield: 139 mg (44%).
13C NMR (125 MHz, CDCl3): d = 199.10, 192.63, 188.05, 164.33,
144.78, 140.04, 134.99, 133.09, 131.31, 129.44, 127.75, 62.59,
29.00, 13.00.
HRMS (EI): m/z [M]+ calcd for C14H14O4: 247.0926; found:
247.0936.
IR (KBr): 2955, 1674, 1573, 1445, 1404, 1216 cm–1.
1H NMR (300 MHz, CDCl3): d = 7.71 (d, J = 8.4 Hz, 2 H), 7.63–
7.59 (m, 4 H), 7.44 (uneven t, J = 7.7, 7.1 Hz, 2 H), 7.35 (d, J = 7.2
Hz, 1 H), 6.91 (s, 1 H), 2.84 (s, 2 H), 2.41 (s, 2 H), 1.20 (s, 6 H).
13C NMR (75 MHz, CDCl3): d = 193.43, 165.64, 140.79, 140.41,
128.86, 127.54, 127.46, 126.95, 124.35, 121.88, 100.97, 52.05,
37.59, 35.32, 28.76.
(4-Hydroxy-2-methoxy-5-phenylfuran-3-yl)pyridin-3-ylmeth-
anone (3h)
Yellow oil; yield: 89 mg (30%).
HRMS (EI): m/z [M]+ calcd for C22H20O2: 316.1497; found:
316.1498.
IR (neat): 3060, 2956, 1719, 1450, 1266, 1176 cm–1.
1H NMR (500 MHz, CDCl3): d = 8.53 (d, J = 10 Hz, 1 H), 8.12 (d,
J = 5 Hz, 1 H), 7.71 (d, J = 10 Hz, 2 H), 7.46–7.40 (m, 5 H), 7.09
(s, 1 H), 3.38 (s, 3 H).
2-(4-Methoxyphenyl)-6,6-dimethyl-6,7-dihydrobenzofuran-
4(5H)-one (6e)
White solid; mp 131–133 °C; yield: 100 mg (37%).
13C NMR (125 MHz, CDCl3): d = 170.01, 163.36, 153.59, 148.85,
136.00, 132.91, 130.58, 129.25, 129.00, 128.88, 128.53, 128.48,
128.26, 124.14, 117.25, 107.84, 51.86.
HRMS (EI): m/z [M]+ calcd for C17H13NO4: 296.0878; found:
296.0884.
IR (KBr): 3117, 2962, 1681, 1593, 1499, 1452 cm–1.
1H NMR (300 MHz, CDCl3): d = 7.56 (d, J = 8.8 Hz, 2 H), 6.91 (d,
J = 8.8 Hz, 2 H), 6.73 (s, 1 H), 3.83 (s, 3 H), 2.81 (s, 2 H), 2.39 (s,
2 H), 1.18 (s, 6 H).
13C NMR (75 MHz, CDCl3): d = 193.51, 165.04, 159.58, 125.44,
122.87, 121.77, 114.24, 99.18, 55.23, 52.04, 37.56, 35.32, 28.77.
6,6-Dimethyl-2-phenyl-6,7-dihydrobenzofuran-4(5H)-one (6a)
White solid; mp 100–102 °C; yield: 134 mg (56%).
HRMS (EI): m/z [M]+ calcd for C17H18O3: 270.1289; found:
270.1291.
IR (KBr): 2962, 2867, 1667, 1431, 1222, 764 cm–1.
1H NMR (300 MHz, CDCl3): d = 7.64 (d, J = 7.3 Hz, 2 H), 7.39 (un-
even t, J = 7.8, 7.2 Hz, 2 H), 7.29 (d, J = 7.3 Hz, 1 H), 6.88 (s, 1 H),
2.83 (s, 2 H), 2.40 (s, 2 H), 1.19 (s, 6 H).
13C NMR (75 MHz, CDCl3): d = 193.44, 165.54, 154.59, 129.86,
128.77, 128.03, 123.93, 121.76, 100.84, 52.02, 37.53, 35.29, 28.72.
6,6-Dimethyl-2-p-tolyl-6,7-dihydrobenzofuran-4(5H)-one (6f)
White solid; mp 122–124 °C; yield: 102 mg (40%).
IR (KBr): 3110, 2962, 1681, 1499, 1445, 1222, 838 cm–1.
Synthesis 2011, No. 15, 2466–2470 © Thieme Stuttgart · New York