204
C. Curti et al. / Tetrahedron 65 (2009) 200–205
NMR (CDCl3),
d
: 13.5 (CH3), 21.6 (CH2), 23.9 (CH2), 53.6 (CH2), 60.1
3.3.5. 5-(4-Nitrophenyl)-2,2-diphenyl-4-(phenylsulfonyl)-2,3-
(CH2), 124.1 (2CH), 130.5 (2CH), 140.0 (C), 188.1 (C), C–NO2 not
observed in these conditions. Anal. Calcd for C12H15NO5S (285.32):
C, 50.52; H, 5.30; N, 4.91. Found: C, 50.85; H, 5.14; N, 5.03.
dihydrofuran (6a)
White crystals, mp 232 ꢀC (isopropyl alcohol), 1H NMR (CDCl3),
: 3.81 (s, 2H, CH2), 7.29–7.31 (m, 10H, CH), 7.40–7.61 (m, 3H, CH),
d
7.68–7.72 (m, 2H, CH), 7.95 (d, J¼9.0 Hz, 2H, CH), 8.28 (d,
3.3. General procedure for Mn(OAc)3-mediated reaction of
J¼9.0 Hz, 2H, CH). 13C NMR (CDCl3),
d: 45.3 (CH2), 92.7 (C), 113.2
b-ketosulfones with alkenes
(C), 123.1 (2CH), 125.5 (4CH), 127.0 (2CH), 128.2 (2CH), 128.6
(4CH), 129.2 (2CH), 130.9 (2CH), 133.3 (CH), 134.4 (C), 141.1 (C),
143.3 (2C), 149.1 (C), 159.3 (C). Anal. Calcd for C28H21NO5S
(483.54): C, 69.55; H, 4.38; N, 2.90. Found: C, 69.57; H, 4.41; N,
2.81.
A solution of manganese(III) acetate dihydrate (6.87 mmol,
1.84 g) and copper(II) acetate (3.27 mmol, 0.59 g) in 30 mL of glacial
acetic acid was heated under microwave irradiation (200 W, 80 ꢀC)
for 15 min, until dissolution. Then, the reaction mixture was cooled
down to 50 ꢀC, and a solution of 3a–d (3.27 mmol) and alkenes 4a–
c (9.81 mmol) in 5 mL acetic acid was added. The mixture was
heated under microwave irradiation (200 W, 80 ꢀC) for 30 min. The
reaction mixture was poured into 200 mL of cold water, and
extracted with chloroform (3ꢁ40 mL). The organic extracts were
collected, washed with saturated aqueous NaHCO3 (3ꢁ40 mL), and
dried (MgSO4). Solvent evaporation was followed by column
chromatography (gradient, from chloroform/petroleum ether (1/1)
to chloroform/petroleum ether/diethyl ether (5/3/2)), and the
product obtained was recrystallized from the appropriate solvent.
3.3.6. 5-(4-Nitrophenyl)-2,2-diphenyl-4-tosyl-2,3-
dihydrofuran (6b)
White crystals, mp 226–227 ꢀC (isopropyl alcohol). 1H NMR
(CDCl3), d: 2.41 (s, 3H, CH3), 3.80 (s, 2H, CH2), 7.22–7.30 (m, 12H,
CH), 7.58 (d, J¼8.2 Hz, 2H, CH), 7.94 (d, J¼9.0 Hz, 2H, CH), 8.28 (d,
J¼9.0 Hz, 2H, CH). 13C NMR (CDCl3),
d: 21.6 (CH3), 45.4 (CH2), 92.5
(C), 113.5 (C), 123.0 (2CH), 125.5 (4CH), 127.1 (2CH), 128.1 (2CH),
128.6 (4CH), 129.8 (2CH), 130.9 (2CH), 134.5 (C), 138.2 (C), 143.4
(2C), 144.3 (C), 149.1 (C), 158.8 (C). Anal. Calcd for C29H23NO5S
(497.56): C, 70.00; H, 4.66; N, 2.82. Found: C, 69.89; H, 4.72; N,
2.68.
3.3.1. 5-(4-Nitrophenyl)-2-phenyl-4-(phenylsulfonyl)-2,3-
dihydrofuran (5a)
3.3.7. 4-(4-Chlorophenylsulfonyl)-5-(4-nitrophenyl)-2,2-diphenyl-
Yellow oil. 1H NMR (CDCl3),
d
: 3.18 (dd, J¼8.7 and 15.0 Hz, 1H,
2,3-dihydrofuran (6c)
CHa), 3.57 (dd, J¼10.6 and 15.0 Hz, 1H, CHb), 5.76 (dd, J¼8.7 and
White crystals, mp 228 ꢀC (ethanol). 1H NMR (CDCl3),
d: 3.78 (s,
10.6 Hz,1H, CH), 7.29–7.65 (m, 8H, CH), 7.75–7.79(m, 2H, CH), 7.95(d,
2H, CH2), 7.26–7.35 (m, 10H, CH), 7.40 (d, J¼8.5 Hz, 2H, CH), 7.60 (d,
J¼8.9 Hz, 2H, CH), 8.28 (d, J¼8.9 Hz, 2H, CH).13C NMR (CDCl3),
d: 39.9
J¼8.5 Hz, 2H, CH), 7.95 (d, J¼8.6 Hz, 2H, CH), 8.30 (d, J¼8.6 Hz, 2H,
(CH2), 83.4 (CH), 112.9 (C), 122.9 (2CH), 125.7 (2CH), 127.0 (2CH),
128.9 (CH), 129.0 (2CH), 129.2 (2CH), 130.8 (2CH), 133.3 (CH), 134.3
(C),139.6 (C),141.0 (C),149.0(C),160.5(C). Anal. Calcdfor C22H17NO5S
(407.44): C, 64.85; H, 4.21; N, 3.44. Found: C, 64.45; H, 4.55; N, 3.09.
CH). 13C NMR (CDCl3),
d: 45.2 (CH2), 92.9 (C), 112.7 (C), 123.1 (2CH),
125.5 (4CH), 128.3 (2CH), 128.4 (2CH), 128.7 (4CH), 129.5 (2CH),
131.0 (2CH), 134.1 (C), 139.5 (C), 140.0 (C), 143.1 (2C), 149.3 (C), 159.9
(C). Anal. Calcd for C28H20ClNO5S (517.98): C, 64.93; H, 3.89; N, 2.70.
Found: C, 64.98; H, 3.93; N, 2.68.
3.3.2. 5-(4-Nitrophenyl)-2-phenyl-4-tosyl-2,3-dihydrofuran (5b)
Yellow oil. 1H NMR (CDCl3),
d
: 2.42 (s, 3H, CH3), 3.16 (dd, J¼8.9 and
3.3.8. 4-(Butylsulfonyl)-5-(4-nitrophenyl)-2,2-diphenyl-2,3-
dihydrofuran (6d)
15.0 Hz, 1H, CHa), 3.55(dd,J¼10.8and15.0 Hz,1H,CHb),5.74(dd, J¼8.9
and 10.8 Hz,1H, CH), 7.23–7.39 (m, 7H, CH), 7.65 (d, J¼8.3 Hz, 2H, CH),
7.94 (d, J¼9.0 Hz, 2H, CH), 8.26 (d, J¼9.0 Hz, 2H, CH).13C NMR (CDCl3),
Yellow crystals, mp 168–169 ꢀC (isopropyl alcohol). 1H NMR
(CDCl3),
d: 0.77 (t, J¼7.2 Hz, 3H, CH3), 1.17–1.35 (m, 2H, CH2), 1.46–
d
: 21.5 (CH3), 40.0 (CH2), 83.3 (CH),113.2 (C),122.9 (2CH),125.7 (2CH),
1.57 (m, 2H, CH2), 2.87–2.95 (m, 2H, CH2), 3.97 (s, 2H, CH2), 7.33–
127.1 (2CH), 128.8 (CH), 128.9 (2CH), 129.8 (2CH), 130.8 (2CH), 134.4
(C), 138.1 (C), 139.6 (C), 144.4 (C), 149.0 (C), 160.0 (C). HMRS (EI): m/z
calcd for C23H19NO5S MþHþ: 422.1057, found: 422.1056.
7.46 (m, 10H, CH), 8.05 (d, J¼9.0 Hz, 2H, CH), 8.30 (d, J¼9.0 Hz, 2H,
CH). 13C NMR (CDCl3),
d: 13.4 (CH3), 21.4 (CH2), 24.4 (CH2), 46.1
(CH2), 55.0 (CH2), 92.5 (C), 111.3 (C), 123.2 (2CH), 125.5 (4CH), 128.3
(2CH), 128.8 (4CH), 130.8 (2CH), 134.3 (C), 143.5 (2C), 149.2 (C),
159.7 (C). Anal. Calcd for C26H25NO5S (463.55): C, 67.37; H, 5.44; N,
3.02. Found: C, 67.29; H, 5.58; N, 3.01.
3.3.3. 4-(4-Chlorophenylsulfonyl)-5-(4-nitrophenyl)-2-phenyl-2,3-
dihydrofuran (5c)
Yellow oil. 1H NMR (CDCl3),
d
: 3.17 (dd, J¼8.7 and 14.9 Hz, 1H,
CHa), 3.55 (dd, J¼10.7 and 14.9 Hz, 1H, CHb), 5.78 (dd, J¼8.7 and
10.7 Hz, 1H, CH), 7.26–7.54 (m, 7H, CH), 7.70 (d, J¼8.5 Hz, 2H, CH),
7.94 (d, J¼8.7 Hz, 2H, CH), 8.28 (d, J¼8.7 Hz, 2H, CH). 13C NMR
3.3.9. 3-(4-Nitrophenyl)-1-(phenylsulfonyl)-1,2,3,4-tetrahydro
naphthalene (7a)
White crystals, mp 180 ꢀC (cyclohexane). 1H NMR (CDCl3),
d:
(CDCl3),
d: 39.8 (CH2), 83.5 (CH), 112.4 (C), 123.0 (2CH), 125.6 (2CH),
2.28–2.95 (m, 5H, 2CH2þ1CH), 4.70 (dd, J¼6.9 and 9.6 Hz, 1H, CH),
128.5 (2CH), 128.7 (CH), 129.0 (2CH), 129.6 (2CH), 130.8 (2CH), 134.1
(C), 139.4 (C), 139.5 (C), 147.2 (C), 149.1 (C), 161.0 (C). HMRS (EI): m/z
calcd for C22H16ClNO5S MþHþ: 442.0510, found: 442.0502.
7.07–7.67 (m, 11H, CH), 8.19 (d, J¼8.8 Hz, 2H, CH). 13C NMR (CDCl3),
d: 31.3 (CH2), 36.6 (CH2), 40.8 (CH), 65.3 (CH), 124.0 (2CH), 126.7
(CH), 126.8 (C), 127.8 (2CH), 128.8 (2CH), 128.9 (2CH), 129.6 (2CH),
131.4 (CH), 133.9 (CH), 136.2 (C), 140.0 (C), 147.0 (C), 151.9 (C). Anal.
Calcd for C22H19NO4S (393.46): C, 67.16; H, 4.87; N, 3.56. Found: C,
66.97; H, 4.99; N, 3.53.
3.3.4. 4-(Butylsulfonyl)-5-(4-nitrophenyl)-2-phenyl-2,3-
dihydrofuran (5d)
Yellow oil. 1H NMR (CDCl3),
d
: 0.88 (t, J¼7.2 Hz, 3H, CH3), 1.30–
1.48 (m, 2H, CH2), 1.63–1.81 (m, 2H, CH2), 2.95–3.03 (m, 2H, CH2),
3.30 (dd, J¼8.9 and 15.1 Hz, 1H, CHa), 3.72 (dd, J¼10.8 and 15.1 Hz,
1H, CHb), 5.86 (dd, J¼8.9 and 10.8 Hz, 1H, CH), 7.30–7.51 (m, 5H,
CH), 8.00 (d, J¼8.9 Hz, 2H, CH), 8.27 (d, J¼8.9 Hz, 2H, CH). 13C NMR
3.3.10. 3-(4-Nitrophenyl)-1-tosyl-1,2,3,4-tetrahydro
naphthalene (7b)
Yellow crystals, mp 194 ꢀC (isopropyl alcohol). 1H NMR (CDCl3),
d
: 2.26–2.97 (m, 5H, 2CH2þCH), 2.43 (s, 3H, CH3), 4.68 (dd, J¼7.0
and 9.3 Hz, 1H, CH), 7.07–7.47 (m, 10H, CH), 8.20 (d, J¼8.7 Hz, 2H,
CH). 13C NMR (CDCl3),
: 21.6 (CH3), 31.4 (CH2), 36.7 (CH2), 40.8
(CDCl3), d: 13.5 (CH3), 21.4 (CH2), 24.3 (CH2), 40.5 (CH2), 54.7 (CH2),
83.2 (CH), 111.1 (C), 123.1 (2CH), 125.6 (2CH), 129.0 (CH), 129.1
(2CH), 130.7 (2CH), 134.2 (C), 139.7 (C), 149.1 (C), 161.0 (C). HMRS
(EI): m/z calcd for C20H21NO5S MþHþ: 388.1213, found: 388.1209.
d
(CH), 65.3 (CH),124.0 (2CH),126.6 (CH), 126.9 (C),127.8 (2CH),128.6
(CH), 128.7 (CH), 129.5 (2CH), 129.6 (2CH), 131.4 (CH), 133.3 (C),