6
Tetrahedron
ACCEPTED MANUSCRIPT
163.74, 163.61, 161.26, 161.15, 149.38, 149.21, 131.72,
White solid (41.7 mg, yield: 99%), m.p. 123–125 ºC. 1H NMR
131.45, 131.37, 128.61, 128.53, 128.42, 126.94, 126.91, 126.50,
125.34, 123.81, 121.12, 120.06, 118.12, 117.46, 116.28, 116.06,
115.75, 115.54. HRMS (ESI): m/z Calcd for [C24H14F2NaO, M +
Na]+: 379.09049, Found: 379.09011.
(400 MHz, CDCl3): δ 8.13 (d, J = 8.8 Hz, 1H), 7.98 (d, J = 8.2
Hz, 1H), 7.61 – 7.35 (m, 5H), 7.32 – 7.15 (m, 5H), 6.84 (d, J =
7.7 Hz, 1H), 3.98 (s, 3H). 13C NMR (100 MHz, CDCl3): δ
155.95, 150.05, 149.64, 134.19, 133.91, 132.24, 132.16, 131.60,
130.24, 130.13, 129.98, 129.93, 129.13, 126.80, 126.51, 124.76,
123.31, 122.32, 119.10, 118.31, 117.42, 112.52, 104.06, 55.53.
HRMS (ESI): m/z Calcd for [C25H16Cl2NaO2, M + Na]+:
441.04213, Found: 441.04196.
8-bromo-2,3-bis(4-fluorophenyl)naphtho[1,2-b]furan (2o)
White solid (43 mg, yield: 99%), m.p. 169–171 ºC. 1H NMR
(400 MHz, CDCl3): δ 8.49 (s, 1H), 7.75 (d, J = 8.6 Hz, 1H), 7.66
– 7.61 (m, 2H), 7.55 (dd, J = 14.9, 8.7 Hz, 2H), 7.48 – 7.42 (m,
3H), 7.18 (t, J = 8.1 Hz, 2H), 7.03 (t, J = 8.2 Hz, 2H). 13C NMR
(100 MHz, CDCl3): δ 163.92, 163.72, 161.44, 161.25, 149.87,
148.22, 131.45, 131.37, 130.10, 130.02, 128.70, 128.62, 128.32,
128.29, 126.63, 126.60, 126.27, 123.58, 122.50, 122.07, 120.66,
118.61, 117.43, 116.36, 116.15, 115.83, 115.62. HRMS (ESI):
m/z Calcd for [C24H13BrF2NaO, M + Na]+: 457.00101, Found:
457.00079.
2,3-bis(4-bromophenyl)naphtho[1,2-b]furan (2u)
White solid (46.3 mg, yield: 97%), m.p. 152–154 ºC. 1H NMR
(400 MHz, CDCl3): δ 8.36 (d, J = 8.2 Hz, 1H), 7.90 (d, J = 8.1
Hz, 1H), 7.65 – 7.56 (m, 4H), 7.55 – 7.40 (m, 6H), 7.35 (d, J =
8.3 Hz, 2H). 13C NMR (100 MHz, CDCl3): δ 149.62, 148.99,
132.35, 131.86, 131.76, 131.56, 131.30, 129.44, 128.43, 128.14,
126.57, 125.53, 124.99, 124.00, 122.37, 121.98, 121.09, 120.10,
118.12, 117.99. HRMS (ESI): m/z Calcd for [C24H14Br2NaO, M
+ Na]+: 498.93036, Found: 498.93019.
2,3-bis(4-fluorophenyl)-8-methoxynaphtho[1,2-b]furan (2p)
White solid (35.6 mg, yield: 92%), m.p. 148–150 ºC. 1H NMR
(400 MHz, CDCl3): δ 7.82 (d, J = 8.9 Hz, 1H), 7.71 – 7.62 (m,
3H), 7.58 (d, J = 8.5 Hz, 1H), 7.51 – 7.44 (m, 2H), 7.35 (d, J =
8.5 Hz, 1H), 7.22 – 7.12 (m, 3H), 7.05 (t, J = 8.6 Hz, 2H), 4.02
(s, 3H). 13C NMR (100 MHz, CDCl3): δ 163.80, 163.63, 161.32,
161.17, 158.38, 149.26, 149.06, 131.48, 131.40, 130.09, 128.76,
128.73, 128.68, 127.05, 127.00, 125.80, 123.58, 122.05, 117.68,
117.61, 116.25, 116.04, 115.75, 115.57, 115.53, 55.54. HRMS
(ESI): m/z Calcd for [C25H16F2NaO2, M + Na]+: 409.10106,
Found: 409.10083.
2,3-diphenylbenzofuran (4a)
White solid (26.7 mg, yield: 99%), m.p. 121–123 ºC. 1H NMR
(400 MHz, CDCl3): δ 7.71 – 7.62 (m, 2H), 7.55 (d, J = 8.1 Hz,
1H), 7.53 – 7.43 (m, 5H), 7.43 – 7.37 (m, 1H), 7.32 (dd, J = 14.0,
7.2 Hz, 4H), 7.23 (t, J = 7.5 Hz, 1H). 13C NMR (100 MHz,
CDCl3): δ 153.98, 150.51, 132.84, 130.65, 130.23, 129.75,
128.95, 128.40, 128.33, 127.61, 127.01, 124.66, 122.89, 120.01,
117.49, 111.09. HRMS (ESI): m/z Calcd for [C20H14NaO, M +
Na]+: 293.09369, Found: 293.09328.
2,3-bis(4-fluorophenyl)-6-methoxynaphtho[1,2-b]furan (2q)
2,3-bis(4-fluorophenyl)benzofuran (4b)
1
White solid (38.2 mg, yield: 99%), m.p. 139–141 ºC. 1H NMR
(400 MHz, CDCl3): δ 8.08 (d, J = 8.8 Hz, 1H), 7.96 (d, J = 8.2
Hz, 1H), 7.65 (dd, J = 8.7, 5.4 Hz, 2H), 7.54 – 7.44 (m, 4H), 7.17
(t, J = 8.6 Hz, 2H), 7.03 (t, J = 8.7 Hz, 2H), 6.86 (d, J = 7.7 Hz,
1H), 4.01 (s, 3H). 13C NMR (100 MHz, CDCl3): δ 163.76,
163.61, 161.29, 161.16, 155.99, 149.38, 149.30, 131.47, 131.39,
128.66, 128.58, 126.97, 126.94, 126.84, 125.84, 123.34, 122.09,
117.74, 117.39, 117.16, 116.25, 116.03, 115.72, 115.51, 112.45,
103.96, 55.55. HRMS (ESI): m/z Calcd for [C25H16F2NaO2, M +
Na]+: 409.10128, Found: 409.10106.
White solid (30 mg, yield: 99%), m.p. 96–98 ºC. H NMR
(400 MHz, CDCl3): δ 7.60 (dd, J = 8.5, 5.5 Hz, 2H), 7.53 (d, J =
7.9 Hz, 1H), 7.44 (dd, J = 8.1, 5.4 Hz, 3H), 7.33 (t, J = 7.7 Hz,
1H), 7.23 (d, J = 7.1 Hz, 1H), 7.16 (t, J = 8.5 Hz, 2H), 7.01 (t, J =
8.6 Hz, 2H). 13C NMR (100 MHz, CDCl3): δ 163.92, 163.60,
161.44, 161.14, 153.87, 149.77, 131.41, 131.33, 130.03, 128.90,
128.82, 128.55, 128.52, 126.71, 126.67, 124.83, 123.09, 119.77,
116.26, 116.20, 116.05, 115.73, 115.52, 111.13. HRMS (ESI):
m/z Calcd for [C20H12F2NaO, M + Na]+: 329.07484, Found:
329.07469.
2,3-bis(2-chlorophenyl)naphtho[1,2-b]furan (2r)
3-(4-chlorophenyl)-2-phenylbenzofuran (4c)
White solid (38.5 mg, yield: 99%), m.p. 129–131 ºC. 1H NMR
(400 MHz, CDCl3): δ 8.41 (d, J = 8.0 Hz, 1H), 7.95 (d, J = 8.0
Hz, 1H), 7.69 (d, J = 8.6 Hz, 1H), 7.61 (t, J = 7.4 Hz, 1H), 7.56 –
7.41 (m, 5H), 7.34 – 7.22 (m, 5H). 13C NMR (100 MHz, CDCl3):
δ 150.11, 149.59, 134.27, 134.01, 132.29, 132.20, 131.76,
131.63, 130.29, 130.17, 130.02, 129.97, 129.19, 128.36, 126.85,
126.54, 126.45, 125.42, 124.30, 123.51, 121.43, 120.19, 119.30,
119.23. HRMS (ESI): m/z Calcd for [C24H14Cl2NaO, M + Na]+:
411.03139, Found: 411.03112.
White solid (30 mg, yield: 99%), m.p. 102–104 ºC. 1H NMR
(400 MHz, CDCl3): δ 7.63 (dd, J = 7.7, 1.8 Hz, 2H), 7.54 (d, J =
8.2 Hz, 1H), 7.47 – 7.39 (m, 5H), 7.36 – 7.27 (m, 4H), 7.23 (t, J
= 7.0 Hz, 1H). 13C NMR (100 MHz, CDCl3): δ 153.98, 150.77,
133.52, 131.35, 131.05, 130.34, 129.83, 129.25, 128.56, 128.51,
127.05, 124.83, 123.05, 119.72, 116.25, 111.19. HRMS (ESI):
m/z Calcd for [C20H13ClNaO, M + Na]+: 327.05471, Found:
327.05453.
2,3-bis(3-methoxyphenyl)benzofuran (4d)
2,3-bis(2-chlorophenyl)-8-methoxynaphtho[1,2-b]furan (2s)
Pale yellow oil (27.4 mg, yield: 83%). 1H NMR (600 MHz,
CDCl3): δ 7.55 (d, J = 8.2 Hz, 1H), 7.50 (d, J = 7.8 Hz, 1H), 7.38
(t, J = 8.1 Hz, 1H), 7.33 (t, J = 7.8 Hz, 1H), 7.27 (d, J = 7.8 Hz,
1H), 7.25 – 7.20 (m, 3H), 7.09 (d, J = 7.5 Hz, 1H), 7.05 (s, 1H),
6.95 (d, J = 8.2 Hz, 1H), 6.84 (d, J = 8.0 Hz, 1H), 3.80 (s, 3H),
3.70 (s, 3H). 13C NMR (100 MHz, CDCl3): δ 159.99, 159.44,
153.84, 150.30, 134.15, 131.74, 130.19, 129.96, 129.42, 124.74,
122.92, 122.24, 120.06, 119.47, 117.63, 115.06, 114.78, 113.47,
111.75, 111.07, 55.26, 55.08. HRMS (ESI): m/z Calcd for
[C22H18NaO3, M + Na]+: 353.11482, Found: 353.11449.
White solid (41.5 mg, yield: 99%), m.p. 203–205 ºC. 1H NMR
(400 MHz, CDCl3): δ 7.84 (d, J = 8.9 Hz, 1H), 7.68 (s, 1H), 7.62
(d, J = 8.5 Hz, 1H), 7.53 – 7.42 (m, 3H), 7.37 (d, J = 8.5 Hz, 1H),
7.34 – 7.22 (m, 5H), 7.19 – 7.14 (m, 1H), 3.99 (s, 3H). 13C NMR
(100 MHz, CDCl3): δ 158.33, 149.72, 149.53, 134.24, 134.05,
132.28, 132.26, 131.62, 130.24, 130.22, 130.00, 129.15, 126.99,
126.82, 126.55, 124.74, 123.24, 122.28, 119.30, 117.78, 116.72,
98.90, 55.54. HRMS (ESI): m/z Calcd for [C25H16Cl2NaO2, M +
Na]+: 441.04196, Found: 441.04163.
2,3-bis(2-chlorophenyl)-6-methoxynaphtho[1,2-b]furan (2t)
6-methyl-2,3-diphenylbenzofuran (4e)