550
I. El-Sayed
3,6-Dihydro-4,5-dimethyl-2-(p-chlorophenylsulfonyl)-2-(pentachlorophenylthio)-
2H-thiopyran-S-oxide (6b, C19H14Cl6O3S3)
The procedure as given for 6a was followed starting from 250 mg of 5b (0.48 mmol) and 0.54cm3
of 2,3-dimethyl-1,3-butadiene (4.80 mmol). The cycloadduct 6b was obtained as colorless crystals
1
(265 mg, 92%), mp 174ꢂC; IR (KBr): ꢁꢀ¼ 1147, 1310 (vSO ), 1089 (vS¼O) cmꢁ1; H NMR (CDCl3):
2
ꢀ ¼ 1.19 (s, 3H), 1.60 (s, 3H), 2.63 and 3.02 (ABq, J ¼ 18.60Hz, 2H), 3.74 and 4.01 (ABq,
J ¼ 16.20 Hz, 2H), 7.55 (d, J ¼ 8.40 Hz, 2H), 8.16 (d, J ¼ 8.40 Hz, 2H) ppm; 13C NMR (CDCl3):
ꢀ ¼ 18.91, 19.19, 33.69, 54.71, 96.30, 120.77, 125.97, 128.64, 129.03, 129.42, 130.07, 132.77,
134.03, 136.79, 141.97 ppm; MS: m=z (%) ¼ 596 (62, Mþ).
3,6-Dihydro-5-methyl-2-(phenylsulfonyl)-2-(pentachlorophenylthio)-2H-
thiopyran-S-oxide (7a, C18H13Cl5O3S3)
The procedure as given for 6a was followed starting from 250 mg of 5a (0.52 mmol) and 0.52 cm3 of
2-methyl-1,3-butadiene (5.20 mmol). After stirring for 2 h at room temperature, the volatiles were
evaporated in vacuo and the crude product was crystallized from CH2Cl2:diethyl ether (1:3) and
cooling gave 7a as colorless crystals (257mg, 90%), mp 138ꢂC; IR (KBr): ꢁꢀ¼ 1156, 1315 (vSO
)
2
1083 (vS¼O) cmꢁ1; 1H NMR (CDCl3): ꢀ ¼ 1.68 (s, 3H), 2.72 (m, 1H), 3.00 (part of ABq, J ¼ 19.20 Hz,
1H), 3.80 and 3.93 (ABq, J ¼ 16.60 Hz, 2H), 5.04 (m, 1H), 7.60 (m, 2H), 7.72 (m, 1H), 8.20 (d,
J ¼ 7.60Hz, 2H) ppm; 13C NMR (CDCl3): ꢀ ¼ 23.32, 27.93, 53.75, 94.81, 118.63, 128.27, 128.70,
131.10, 131.27, 132.42, 134.93, 135.55, 136.85, 141.30ppm; MS: m=z (%) ¼ 548 (24, Mþ).
3,6-Dihydro-5-methyl-2-(p-chlorophenylsulfonyl)-2-(pentachlorophenylthio)-
2H-thiopyran-S-oxide (7b, C18H12Cl6O3S3)
The procedure as given for 6a was followed starting from 250 mg of 5b (0.48 mmol) and 0.48cm3 of 2-
methyl-1,3-butadiene (5.20 mmol). After stirring for 2 h at room temperature, the volatiles were evapo-
rated in vacuo and the crude product was crystallized from CH2Cl2:diethyl ether (1:3) and cooling gave
7b as colorless crystals (255 mg, 91%), mp 152ꢂC; IR (KBr): ꢁꢀ¼ 1155, 1313 (vSO ), 1085 (vSO) cmꢁ1; 1H
2
NMR (CDCl3): ꢀ ¼ 1.68 (s, 3H), 2.73 (m, 1H), 3.03 (d, part of ABq, J ¼ 18.80Hz, 2H), 3.80 (d, part of
ABq, J ¼ 16.40 Hz, 1H), 3.99 (d, part of ABq, J ¼ 16.40 Hz, 1H), 5.00 (m, 1H), 7.56 (d, J ¼ 8.40Hz, 1H),
8.16 (d, J ¼ 8.40Hz, 2H) ppm; 13C NMR (CDCl3): ꢀ ¼ 23.24, 27.93, 53.80, 95.28, 118.63, 128.42,
128.60, 129.01, 129.40, 130.06, 132.76, 134.05, 138.45, 142.00 ppm; MS: m=z (%) ¼ 582 (57, Mþ).
3,6-Dihydro-3-methyl-2-(phenylsulfonyl)-2-(pentachlorophenylthio)-
2H-thiopyran-S-oxide (8a, C18H13Cl5O3S3)
The procedure as given for 6a was followed starting from 300 mg of 5a (0.62 mmol) and 0.62 cm3 of
trans-piperylene (6.20 mmol). After stirring for 2 h at room temperature, the volatiles were evaporated
in vacuo and the crude product was crystallized from CH2Cl2:diethyl ether (1:3) to give 8a as colorless
1
crystals (325mg, 95%), mp 119ꢂC; IR (KBr): ꢁꢀ¼ 1155, 1311 (vSO ), 1090 (vS¼O) cmꢁ1; H NMR
2
(CDCl3): ꢀ ¼ 1.82 (d, J ¼ 7.20 Hz, 3H), 3.08 (m, 1H), 3.73 (m, 1H), 4.27 (d, part of ABq, J ¼ 16.40 Hz,
1H), 5.52 (d, J ¼ 10.40 Hz, 1H), 5.62 (m, 1H), 7.60 (m, 2H), 7.72 (m, 1H), 8.09 (d, J ¼ 7.60Hz, 2H)
ppm; 13C NMR (CDCl3): ꢀ ¼ 18.41, 38.14, 48.15, 96.47, 118.57, 124.75, 129.05, 131.18, 131.93,
133.85, 135.04, 135.61, 136.95, 142.43 ppm; MS: m=z (%) ¼ 548 (45, Mþ).
3,6-Dihydro-3-methyl-2-(p-chlorophenylsulfonyl)-2-(pentachlorophenylthio)-
2H-thiopyran-S-oxide (8b, C18H12Cl6O3S3)
The procedure as given for 6a was followed starting from 250mg of 5b (0.48 mmol) and 0.48cm3 of
trans-piperylene (4.80 mmol). After stirring for 2 h at room temperature, the volatiles were evaporated