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hexane) 0.58; IR (KBr) nmax 3057, 2992, 1606, 1581, 1452, 748,
707 cmꢀ1. 1H NMR (400 MHz; CDCl3) 7.67e7.70 (2H, m, 2-CH3Ph),
7.41e7.43 (2H, m, 2-CH3Ph), 4.55 (1H, d, J¼8.3 Hz, 2-H), 4.17 (1H,
ddd, J¼8.3, 7.6, 2.5 Hz, 3-H), 3.59 (1H, dd, J¼11.9, 7.6 Hz, 4-Hb), 3.27
(1H, dd, J¼11.9, 2.5 Hz, 4-Ha), 2.37 (3H, s, CH3); 13C NMR (100 MHz,
ClPh); 13C NMR (100 MHz, CDCl3) 137.5, 133.9, 129.6, 128.7, 127.6,
126.5, 112.3, 97.1, 43.7, 33.2; EIMS (m/z)¼286, 288 (Mþ, Mþþ2).
4.4.4. 2-(4-Methoxyphenyl)-3-nitro-4-thiocyanatothietane (trans-
6d). Yield (1.31 g, 93%) as a white solid; mp 174e177 ꢃC; [Found: C,
46.48; H, 3.81; N, 9.58 C11H10N2O3S2 requires C, 46.79; H, 3.57; N,
9.92%]; Rf (5% EtOAc/hexane) 0.50; IR (KBr) nmax 3054, 2998, 2194,
2069, 1602, 1581, 1452, 754, 708 cmꢀ1; 1H NMR (400 MHz; CDCl3)
8.01e8.04 (2H, m, 4-OCH3Ph), 7.66e7.69 (2H, m, 4-OCH3Ph), 4.52
(1H, d, J¼8.6 Hz, 4-H), 4.13 (1H, dd, J¼8.6, 7.9 Hz, 3-H), 3.81 (3H, s,
OCH3), 3.47 (1H, d, J¼7.9 Hz, 2-H); 13C NMR (100 MHz, CDCl3) 158.3,
132.1,129.4, 114.7,111.5, 97.6, 55.4, 43.9, 42.1; EIMS (m/z)¼282 (Mþ).
CDCl3): d 137.4, 135.8, 129.5, 128.2, 126.7, 125.1, 91.3, 39.7, 27.5, 17.2;
EIMS (m/z)¼229 (Mþ).
4.3.8. 3-(3-Nitrothietan-2-yl)furan (trans-4h). Yield (0.84 g, 87%) as
a white solid; mp 168e171 ꢃC; [Found: C, 45.61; H, 4.17; N, 7.24
C7H7NO3S C, 45.40; H, 3.81; N, 7.56%]; Rf (5% EtOAc/hexane) 0.55; IR
(KBr) nmax 3051, 2999, 1603, 1585, 1454, 745, 701 cmꢀ1 1H NMR
.
(400 MHz; CDCl3) 7.70 (1H, dd, J¼1.8 Hz, 3-furyl), 6.96 (1H, d,
J¼3.5 Hz, 3-furyl), 6.61(1H, dd, J¼3.5 Hz,1.8 Hz, 3-furyl), 4.52 (1H, d,
J¼8.5 Hz, 2-H), 4.19 (1H, ddd, J¼8.5, 7.8, 2.9 Hz, 3-H), 3.66 (1H, dd,
J¼11.2, 7.8 Hz, 4-Hb), 3.22 (1H, dd, J¼11.2, 2.9 Hz, 4-Ha); 13C NMR
4.4.5. 3-Nitro-2-phenyl-4-thiocyanatothietane
(trans-6e). Yield
(1.28 g, 85%) as a white solid; mp 179e182 ꢃC; [Found: C, 59.74; H,
4.11; N, 4.35 C15H13NO2S2 requires C, 59.38; H, 4.32; N, 4.62%]; Rf
(5% EtOAc/hexane) 0.57; IR (KBr) nmax 3050, 2996, 2195, 2072, 1602,
1583, 1456, 755, 705 cmꢀ1; 1H NMR (400 MHz; CDCl3) 3.46 (1H, d,
J¼7.9 Hz, 2-H), 4.17 (1H, dd, J¼8.8, 7.9 Hz, 3-H), 4.50 (1H, d,
J¼8.8 Hz, 4-H), 7.32e7.79 (10H, m, Ph); 13C NMR (100 MHz, CDCl3)
139.7, 136.4, 130.6, 129.5, 128.6, 127.8, 126.8, 125.4, 96.8, 44.1, 42.4;
EIMS (m/z)¼303 (Mþ).
(100 MHz, CDCl3):
d 27.2, 37.9, 91.4, 110.7, 118.4, 139.6, 142.9. EIMS
(m/z)¼195 (Mþ).
4.4. General procedure for the synthesis of 2,3,4-trisubs-
tituted thietanes 6
To a solution of BayliseHillman adduct 1 (5 mmol) in dry THF
(4 mL) was added IBX (5 mmol) and stirred at rt for 5 h to get
a
,
b
-
4.4.6. 2-(4-Chlorophenyl)-3-nitro-4-(phenylthio)thietane
(trans
unsaturated aldehyde 3. Then, to a solution of O,O-diethyl hydrogen
phosphorodithioate 2 (5 mmol) in dry THF (5 mL) was added
dropwise a suspension of NaH (10 mmol) in dry THF (20 mL) with
stirring to rt. After the addition was complete and evolution of
hydrogen gas (effervescence) had ceased, the reaction mixture was
stirred at 60 ꢃC for 30 min and then cooled to rt. In this solution was
6f). Yield (1.54 g, 91%) as a white solid; mp 167e170 ꢃC; [Found: C,
53.01; H, 3.30; N, 4.41 C15H12ClNO2S2 C, 53.33; H, 3.58; N, 4.15%]; Rf
(5% EtOAc/hexane) 0.53; IR (KBr) nmax 3057, 2995, 2192, 1608, 1587,
1454, 751, 706 cmꢀ1; 1H NMR (400 MHz; CDCl3) 8.12e8.18 (2H, m,
4-ClPh), 8.05e8.10 (2H, m, 4-ClPh), 7.37e7.78 (5H, m, Ph), 4.55 (1H,
d, J¼8.9 Hz, 4-H), 4.19 (1H, dd, J¼8.9, 7.6 Hz, 3-H), 3.49 (1H, d,
J¼7.6 Hz, 2-H); 13C NMR (100 MHz, CDCl3) 137.8, 130.7, 129.8, 128.5,
126.4, 125.5, 97.3, 44.5, 42.7; EIMS (m/z)¼337, 339 (Mþ, Mþþ2).
added
a,b-unsaturated aldehyde 3 followed by [bmim]XeY
(5 mmol) and the reaction mixture was stirred at rt for 2e4 h.
Water (30 mL) was added, the mixture was extracted with ether
(3ꢂ30 mL), the combined organic layers were dried over anhydrous
sodium sulfate, filtered and evaporated under reduced pressure.
The crude product thus obtained was purified by silica gel column
chromatography (hexane/EtOAc, 95:5) to afford an analytically
pure sample of 6.
4.4.7. 2-(2-Chlorophenyl)-3-nitro-4-(phenylthio)thietane
(trans
6g). Yield (1.52 g, 90%) as a white solid; mp 174e177 ꢃC; [Found: C,
53.52; H, 3.91; N, 4.42 C15H12ClNO2S2 requires C, 53.33; H, 3.58; N,
4.15%]; Rf (5% EtOAc/hexane) 0.55; IR (KBr) nmax 3054, 2998, 2194,
1602, 1581, 1452, 754, 708 cmꢀ1 1H NMR (400 MHz; CDCl3) 3.47
;
(1H, d, J¼7.9 Hz, 2-H), 4.13 (1H, dd, J¼8.6, 7.9 Hz, 3-H), 4.52 (1H, d,
J¼8.6 Hz, 4-H), 7.35e7.71 (5H, m, Ph), 8.07e8.11 (2H, m, 2-ClPh),
8.12e8.17 (2H, m, 2-ClPh); 13C NMR (100 MHz, CDCl3) 137.4, 136.1,
132.9, 131.8, 130.6, 129.8, 128.9, 128.0, 126.9, 125.7, 96.2, 44.7, 32.9;
EIMS (m/z)¼337, 339 (Mþ, Mþþ2).
4.4.1. 3-Nitro-2-phenyl-4-thiocyanatothietane
(trans-6a). Yield
(1.05 g, 84%) as a white solid; mp 178e180 ꢃC; [Found: C, 47.87; H,
3.41; N, 10.91 C10H8N2O2S2 requires C, 47.60; H, 3.20; N, 11.10%]; Rf
(5% EtOAc/hexane) 0.56; IR (KBr) nmax 3052, 2992, 2195,
2070,1605, 1585, 1455, 750, 705 cmꢀ1 1H NMR (400 MHz; CDCl3)
;
7.38e7.77 (5H, m, Ph), 4.50 (1H, d, J¼8.9 Hz, 4-H), 4.15 (1H, dd,
J¼8.9, 7.7 Hz, 3-H), 3.45 (1H, d, J¼7.7 Hz, 2-H); 13C NMR (100 MHz,
CDCl3) 139.4, 129.9, 128.4, 126.5, 112.1, 97.1, 43.9, 42.5; EIMS (m/z)¼
252 (Mþ).
4.4.8. 2-(4-Methoxyphenyl)-3-nitro-4-(phenylthio)thietanes (trans
6h). Yield (1.53 g, 92%) as a white solid; mp 178e179 ꢃC; [Found: C,
57.96; H, 4.83; N, 4.01 C16H15NO3S2 requires C, 57.64; H, 4.53; N,
4.20%]; Rf (5% EtOAc/hexane) 0.56; IR (KBr) nmax 3054, 2998, 2194,
1602, 1581, 1452, 754, 708 cmꢀ1 1H NMR (400 MHz; CDCl3)
;
4.4.2. 2-(4-Chlorophenyl)-3-nitro-4-thiocyanatothietane
(trans-
8.01e8.04 (m, 2H, 4-OCH3Ph), 7.66e7.69 (m, 2H, 4-OCH3Ph), 4.52
(1H, d, J¼8.6 Hz, 4-H), 4.13 (1H, dd, J¼8.6, 7.9 Hz, 3-H), 2.32 (3H, s,
CH3); 13C NMR (100 MHz, CDCl3) 158.5, 136.7, 131.8, 130.4. 129.1,
127.2, 125.8, 114.9, 97.6, 55.1, 44.5, 42.4; EIMS (m/z)¼333 (Mþ).
6b). Yield (1.34 g, 94%) as a white solid; mp 174e179 ꢃC; [Found: C,
41.58; H, 2.20; N, 9.48 C10H7ClN2O2S2 requires C, 41.88; H, 2.46; N,
9.77%]; Rf (5% EtOAc/hexane) 0.49; IR (KBr) nmax 3051, 2995, 2194,
2071, 1601, 1585, 1457, 751, 702 cmꢀ1 1H NMR (400 MHz; CDCl3)
;
8.10e8.17 (2H, m, 4-ClPh), 8.09e8.13 (2H, m, 4-ClPh), 4.54 (1H, d,
J¼8.7 Hz, 4-H), 4.17 (1H, dd, J¼8.7, 7.8 Hz, 3-H), 3.41 (1H, d, J¼7.8 Hz,
2-H); 13C NMR (100 MHz, CDCl3) 137.9, 131.8, 129.0, 128.7, 111.4,
97.5, 43.1, 42.9; EIMS (m/z)¼286, 288 (Mþ, Mþþ2).
4.4.9. 3-Nitro-4-phenylthietan-2-yl-nitrate (trans-6i). Yield (1.06 g,
83%) as a white solid; mp 178e182 ꢃC; [Found: C, 42.39; H 3.57; N,
9.57 C9H8N2O4S requires C, 42.19; H, 3.15; N, 10.93%]; Rf (5% EtOAc/
hexane) 0.55; IR (KBr) nmax 3056, 2997, 2192, 1602, 1584, 1454, 754,
702 cmꢀ1 1H NMR (400 MHz; CDCl3) 7.35e7.77 (5H, m, Ph), 4.56
;
4.4.3. 2-(2-Chlorophenyl)-3-nitro-4-thiocyanatothietane
(trans-
(1H, d, J¼8.5 Hz, 4-H), 4.14 (1H, dd, J¼8.5, 7.4 Hz, 3-H), 3.44 (1H, d,
J¼7.4 Hz, 2-H); 13C NMR (100 MHz, CDCl3) 139.7, 130.2, 128.9, 126.4,
92.1, 85.7, 42.4; EIMS (m/z)¼256 (Mþ).
6c). Yield (1.24 g, 87%) as a white solid; mp 171e173 ꢃC; [Found: C,
42.13; H, 2.27; N, 9.98 C10H7ClN2O2S2 C, 41.88; H, 2.46; N, 9.77%]; Rf
(5% EtOAc/hexane) 0.52; IR (KBr) nmax 3054, 2991, 2197, 2070, 1606,
1581, 1454, 754, 701 cmꢀ1; 1H NMR (400 MHz; CDCl3) 3.43 (1H, d,
J¼7.6 Hz, 2-H), 4.12 (1H, dd, J¼8.9, 7.6 Hz, 3-H), 4.56 (1H, d,
J¼8.9 Hz, 4-H), 8.09e8.13 (2H, m, 2-ClPh), 8.10e8.17 (2H, m, 2-
4.4.10. 3-Nitro-4-phenylthietan-2-yl-trifluoromethanesulfonate
(trans-6j). Yield (1.54 g, 90%) as a white solid; mp 176e179 ꢃC;
[Found: C, 34.63; H, 2.65; N, 3.87 C10H8F3NO5S2 requires C, 34.99; H,