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D. I. MAGEE ET AL.
2880 (s), 2363 (w), 2333 (w), 2217 (w), 1737 (s), 1597 (s), 1501 (s), 1443 (s), 1387 (s),
1348 (s), 1278 (s), 1243 (s), 1125 (s), 1063 (s). MS (CI) major peaks: 292, 293, 295,
296, 297, 303, 304, 309 (base peak). HRMS (mþ þ H) calcd. for C13H21N5O2S
311.1418, found 311.1418.
PT Sulfone 15
A round-bottomed flask was charged with sulfide 14 (0.31 g, 1.0 mmol) and
ethanol (30 mL), and the solution was cooled to 0 ꢂC. Then (NH4)6Mo2O24 ꢃ 4H2O
(0.12 g, 0.1 mmol) in 30% H2O2 (1.0 mL, 1.0 mmol) was added, and the reaction mix-
ture was allowed to slowly warm to room temperature and stir overnight. Water
(200 mL) and CH2Cl2 (25 mL) were added, and the layers were separated. The aque-
ous phase was extracted with CH2Cl2 (2 ꢄ 25 mL), and the combined organic phases
were dried (MgSO4) and concentrated by rotary evaporation. Column chromato-
graphy (EtOAc=Hexanes 1:2) yielded the sulfone 15 as a clear, colorless liquid
(0.25 g, 0.73 mmol, 73%). Rf ¼ 0.27 (1:6 EtOAc=hexanes). 1H NMR (CDCl3,
400 MHz): d 7.55–7.69 (m, 5H), 4.68 (t, 1H, J ¼ 5.1 Hz), 3.83 (AA0XX0, 2H), 3.67
(pentet, 2H, J ¼ 8.4 Hz), 3.52 (pentet, 2H, J ¼ 7.0 Hz), 2.26 (m, 2H), 1.21, (t, 6H,
J ¼ 7.2 Hz). 13C NMR (CDCl3, 100 MHz): d 153.4, 133.1, 131.5, 129.7, 125.2,
100.2, 62.3, 51.8, 26.8, 15.2. IR (KBr windows) cmꢁ1: 3066 (m), 2977 (s), 2933 (s),
1733 (s, br), 1596 (m), 1575 (w), 1498 (s), 1438 (m), 1343 (s), 1237 (m), 1152 (s),
1061 (s). MS (EI) major peaks: 47, 57, 65, 75, 85 (base peak), 103, 118, 157, 165,
195, 267, 283, 311. HRMS (mþ þ H) calcd. for C14H21N4O4S 341.1285, found
341.1284.
trans-Alkene 16
A round-bottomed flask was charged with PT sulfone 15 (4.2 g, 12.4 mmol),
dimethoxyethane (DME) (100 mL) and cooled to ꢁ55 ꢂC. Potassium bis(trimethylsi-
lyl)amide (0.5 M in toluene, 24.8 mL, 12.4 mmol) was added dropwise over 10 min,
and the reaction was stirred at ꢁ55 ꢂC for a further 1 h. Aldehyde 4 (2.9 g,
12.1 mmol) was then added neat at ꢁ55 ꢂC via syringe, and the syringe was rinsed
with THF (2 ꢄ 2 mL). The reaction was stirred at this temperature for a further
1 h and then allowed to warm to room temperature over 1.5 h. The reaction was
quenched with water (70 mL), the layers were separated, the aqueous layer was
extracted with Et2O (3 ꢄ 50 mL), and the combined organic layers were washed with
brine (50 mL) and dried (MgSO4). Column chromatography (1:4 EtOAc=hexanes)
yielded the product 16 (2.6 g, 60%) as a clear, colorless liquid. Rf ¼ 0.66 (6:1
1
hexanes=EtOAc). H NMR (CDCl3, 400 MHz): d 5.32–5.55 (m, 2H), 4.68 (q, 1H,
J ¼ 5.3 Hz), 4.47 (t, 1H, J ¼ 5.9 Hz), 3.36–3.70 (m, 8H), 2.32 (ABMX, 2H), 1.98
(ABMXY, 2H), 1.52–1.58 (m, 2H), 1.29–1.39 (m, 10H), 1.30 (d, 3H, J ¼ 5.4 Hz),
1.204 (t, 3H, J ¼ 7.0 Hz), 1.201 (t, 6H, J ¼ 7.1 Hz). 13C NMR (CDCl3, 100 MHz):
d 133.5, 124.6, 102.8, 99.5, 65.3, 61.0 (2 signals), 60.6, 37.3, 32.7, 29.9, 29.5 (2 sig-
nals), 29.4, 29.1, 26.3, 19.9, 15.3 (3 signals). IR (KBr windows) cmꢁ1: 2975 (s),
2929 (s), 1569 (w), 1444 (w), 1373 (m), 1342 (m), 1129 (s), 1061 (s). MS (EI) major
peaks: 103 (base peak), 121, 163, 181, 207, 225, 253, 283, 299, 329, 343. HRMS
(mþ þ H) calcd. for C20H41O4 345.3006, found 345.3010.