2256
S. Kobayashi et al. / Tetrahedron 69 (2013) 2251e2259
J¼11.1 Hz), 6.23 (d, 1H, J¼11.1 Hz), 2.48 (t, 2H, J¼7.2 Hz), 1.72e1.62
(m, 2H), 1.47e1.35 (m, 2H), 1.31e1.26 (m, 4H), 0.87 (t, 3H, J¼6.9 Hz,
28.7, 22.7, 14.2, 12.9; data for the minor isomer: 1H NMR (300 MHz,
CDCl3)
d
4.05e3.97 (m, 2H), 3.56 (dd,1H, J¼9.0, 6.6 Hz), 3.33 (dd,1H,
H9); 13C NMR (75 MHz, CDCl3)
d
137.3, 127.8, 126.9, 126.8, 126.7,
J¼8.4, 7.2 Hz), 2.75e2.66 (m, 1H), 2.55e2.40 (m, 3H), 2.26e1.90 (m,
2H), 2.62e1.53 (m, 2H),1.42e1.23 (m, 6H),1.06 (d, 3H, J¼6.3 Hz), 0.89
125.6, 125.5, 125.4, 77.6, 77.2, 36.1, 32.8, 31.5, 30.8, 29.5, 28.8, 28.6,
28.4, 28.2, 22.7, 14.1; FT-IR (ZnSe) 3076, 3058, 3022, 2955, 2928,
(t, 3H, J¼7.2 Hz); 13C NMR (75 MHz, CDCl3)
d 75.4, 73.5, 47.1, 39.9,
2870, 2857, 1598, 1571, 1495, 1466, 1446, 1378, 1286, 936 cmꢁ1
;
35.3, 32.9, 31.6, 29.8, 28.7, 22.7, 17.2, 14.2; FT-IR (ZnSe) 2956, 2928,
2856, 1456, 1436, 1380, 1285, 1240, 1052 cmꢁ1; HRMS (FAB): m/z
calcd for C12H24OS [MþH]þ 217.1626, found 217.1600.
HRMS (FAB): m/z calcd for C14H20S [MþH]þ 221.1364, found
221.1373.
4.3.5. Methyl 3-(tributylstannyl)acrylate (4da, E/Z¼56/44). Colorless
oil; the following NMR data were selected from the spectra obtained
by an E/Z mixture. Data for E-isomer: 1H NMR (300 MHz, CDCl3)
4.3.11. Diethyl 3-methyl-4-((tributylstannyl)methyl)cyclopentane-1,1-
dicarboxylate (4ga, dr¼67/33). Colorless oil; the following NMR
data were obtained after separation of the diastereomers by HPLC.
The major isomer was isolated in pure form, while the minor isomer
was not completely separated from the major isomer. Data for the
d
7.75 (d, 1H, J¼19.2 Hz), 6.30 (d, 1H, J¼19.5 Hz), 3.75 (s, 3H),
1.56e1.45 (m, 6H), 1.36e1.24 (m, 6H), 0.99e0.94 (m, 6H), 0.89 (t, 9H,
J¼7.2 Hz). Data for Z-isomer: 1H NMR (300 MHz, CDCl3)
d
7.17 (d, 1H,
major isomer: 1H NMR (300 MHz, CDCl3)
d 4.16 (q, 4H, 7.2 Hz),
J¼13.2 Hz), 6.73 (d, 1H, J¼12.9 Hz), 3.75 (s, 3H), 1.54e1.44 (m, 6H),
1.35e1.23 (m, 6H), 0.99e0.94 (m, 6H), 0.88 (t, 9H, J¼7.5 Hz); FT-IR
(ZnSe) 2955, 2922, 2871, 2854, 1210, 1183, 1145, 1072 cmꢁ1; HRMS
(FAB): m/z calcd for C12H23O2Sn [MꢁC4H9]þ 319.0722, found
319.0741.
2.54e2.43 (m, 1H), 2.40e2.30 (m, 2H), 2.24e2.12 (m, 1H), 2.06e1.99
(m, 2H), 1.86 (dd, 1H, J¼13.2, 9.9 Hz), 1.77e1.63 (m, 1H), 1.52e1.41
(m, 6H), 1.36e1.21 (m, 12H), 0.98e0.71 (m, 18H); FT-IR (ZnSe) 2954,
2928, 2872, 2854, 1736, 1729, 1464, 1446, 1419, 1376, 1366, 1253,
1184, 1153 cmꢁ1; HRMS (FAB): m/z calcd for C21H39O4Sn [MꢁC4H9]þ
475.1874, found 475.1850.
4.3.6. (Z)-Methyl 3-(1,1,1,3,3,3-hexamethyl-2-(trimethylsilyl)trisilan-
2-yl)acrylate (4db, Z-isomer).19 Colorless oil; 1H NMR (300 MHz,
4.3.12. Diethyl 3-((hexylthio)methyl)-4-methylcyclopentane-1,1-
dicarboxylate (4gc, dr¼85/15). Colorless oil; the following NMR
data were selected from the spectra obtained by a mixture of di-
astereomers. Data for the major isomer: 1H NMR (300 MHz, CDCl3)
CDCl3)
d
6.74 (d, 1H, J¼13.8 Hz), 6.59 (d, 1H, J¼13.8 Hz), 3.70 (s, 3H),
0.18 (s, 27H); FT-IR (ZnSe) 3027, 2949, 2894, 1723, 1583, 1435, 1398,
1362, 1244, 1213, 1178, 1007 cmꢁ1; HRMS (FAB): m/z calcd for
C12H29O2Si4 [MꢁCH3]þ 317.1245, found 317.1251.
d
4.17 (q, 4H, J¼7.2 Hz), 2.80e1.98 (m, 10H), 1.61e1.51 (m, 2H),
1.42e1.21 (m, 4H), 1.23 (t, 6H, J¼7.2 Hz), 0.89 (d, 3H, J¼6.9 Hz), 0.88
(t, 3H, J¼6.9 Hz); FT-IR (ZnSe) 2957, 2929, 2872, 2858, 1731, 1464,
1447, 1366, 1254, 1180 cmꢁ1; HRMS (FAB): m/z calcd for C19H35O4S
[MþH]þ 359.2256, found 359.2238.
4.3.7. 3-(1,1,1,3,3,3-Hexamethyl-2-(trimethylsilyl)trisilan-2-yl)propane-
nitrile (4eb).8d Colorless oil; 1H NMR (300 MHz, CDCl3)
(m, 2H), 1.24e1.18 (m, 2H), 0.19 (s, 27H).
d 2.37e2.31
4.3.8. 1,1,1,3,3,3-Hexamethyl-2-((4-methyltetrahydrofuran-3-yl)
methyl)-2-(trimethylsilyl)trisilane (4fb, dr¼68/32).8d Colorless oil; the
following NMR data were selected from the spectra obtained by
a mixture of diastereomers. Data for the major isomer: 1H NMR
4.4. General procedure for the preparation of thiocarbonates
5aed
To a solution of cholesterol (863 mg, 2.23 mmol) in CH2Cl2 (10 mL)
(300 MHz, CDCl3)
d
4.04 (dd, 1H, J¼8.1, 6.9 Hz), 3.99 (dd, 1H,
were added pyridine (485
mL, 6.00 mmol) and phenyl chlor-
J¼8.1, 6.9 Hz), 3.33 (dd, 1H, J¼8.1, 5.1 Hz), 3.30 (dd, 1H, J¼8.1,
4.8 Hz), 1.86e1.66 (m, 2H), 1.18 (dd, 1H, J¼14.4, 3.0 Hz), 1.01 (d,
3H, J¼6.6 Hz), 0.64 (dd, 1H, J¼14.4, 10.5 Hz), 0.17 (s, 27H); 13C
othionoformate (277 L, 2.00 mmol) (For other substrates, CH3CN was
m
used in place of CH2Cl2.). The mixture was stirred at room temperature
for 50 min and diluted with EtOAc. The solution was washed with brine
and dried over anhydrous MgSO4. After concentration, the residue was
purified by flash chromatography on silica gel (hexane/hexane/
EtOAc¼10/1) to give thiocarbonate 5b (1.04 g, 1.99 mmol, 100%).
NMR (75 MHz, CDCl3)
d 76.1, 75.1, 47.0, 44.0, 16.0, 10.0, 1.38; data
for the minor isomer: 1H NMR (300 MHz, CDCl3)
d 3.91 (dd, 1H,
J¼9.0, 6.0 Hz), 3.89 (dd, 1H, J¼8.1, 3.6 Hz), 3.48 (dd, 1H, J¼8.1,
4.2 Hz), 3.37 (t, 1H, J¼7.5 Hz), 2.31e2.17 (m, 2H), 0.95 (dd, 1H,
J¼14.4, 4.2 Hz), 0.94 (d, 3H, J¼6.9 Hz), 0.68 (dd, 1H, J¼14.4,
4.4.1. O-Phenyl O-(((3aR,5R,5aS,8aS,8bR)-2,2,7,7-tetramethylte-
trahydro-3aH-bis([1,3]dioxolo)[4,5-b:40,50-d]pyran-5-yl)methyl)
bonothioate (5a). This compound was obtained from the corre-
9.6 Hz), 0.17 (s, 27H); 13C NMR (75 MHz, CDCl3)
d
75.0, 74.3, 42.1,
car-
37.8, 13.0, 4.6, 1.41; FT-IR (ZnSe) 2952, 2894, 1245, 1045 cmꢁ1
;
HRMS (FAB): m/z calcd for C14H35OSi4 [MꢁCH3]þ 331.1765, found
sponding commercially available alcohol in 93% yield. Colorless solid;
331.1759.
mp 73e76 ꢀC (hexane/CHCl3); 1H NMR (300 MHz, CDCl3)
d 7.45e7.38
(m, 2H), 7.32e7.26 (m, 1H), 7.13e7.09 (m, 2H), 5.58 (d, 1H, J¼5.1 Hz),
4.73 (dd, 1H, J¼11.4, 4.8 Hz), 4.68e4.60 (m, 2H), 4.38e4.25 (m, 3H),
1.55 (s, 3H), 1.48 (s, 3H), 1.36 (s, 3H), 1.35 (s, 3H); 13C NMR (75 MHz,
4.3.9. 5,5-Bis(trimethylsilyl)hexahydro-1H-silolo[3,4-c]furan
(4fb0).20 Colorless oil; 1H NMR (300 MHz, CDCl3)
d 3.93 (dd, 2H,
J¼8.4, 6.9 Hz), 3.42 (dd, 2H, J¼8.1, 5.4 Hz), 2.69e2.57 (m, 2H), 1.04
CDCl3) d 195.2, 153.6, 129.6, 126.7, 122.0, 109.9, 109.0, 96.4, 72.6, 71.1,
(dd, 2H, J¼15.0, 8.1 Hz), 0.76 (dd, 2H, J¼15.0, 6.3 Hz), 0.12 (s, 18H);
70.9, 70.6, 65.6, 26.2, 26.1, 25.1, 24.6; FT-IR (ZnSe) 2989, 2935, 1591,
1492, 1456, 1383, 1373, 1294, 1207, 1166, 1114, 1071, 1008 cmꢁ1; HRMS
(FAB): m/z calcd for C19H25O7S [MþH]þ 397.1321, found 397.1297.
13C NMR (75 MHz, CDCl3)
d
74.8, 46.4, 10.8, ꢁ0.59, ꢁ0.76; MS (EI,
70 eV): m/z (%) 272 ([Mþ], 4),189 (63),157 (65),131 (87),117 (75), 73
(100); HRMS (EI): m/z calcd for C12H28OSi3 [M]þ 272.1448, found
272.1409.
4.4.2. O-Cyclododecyl O-phenyl carbonothioate (5b).10b This com-
pound was obtained from cyclododecanol in 82% yield. Colorless
4.3.10. 3-((Hexylthio)methyl)-4-methyltetrahydrofuran (4fc, dr¼61/
39). Colorless oil; the following NMR data were obtained after
separation of the diastereomers by HPLC. Data for the major isomer:
oil; 1H NMR (300 MHz, CDCl3)
d 7.44e7.38 (m, 2H), 7.31e7.25 (m,
1H), 7.12e7.08 (m, 2H), 5.55e5.47 (m, 1H), 1.94e1.70 (m, 4H),
1.52e1.32 (m, 18H); HRMS (FAB): m/z calcd for C19H29O2S [MþH]þ
321.1888, found 321.1856.
1H NMR (300 MHz, CDCl3)
d 3.98e3.91 (m, 2H), 3.63e3.58 (m, 1H),
3.47 (dd, 1H, J¼8.4, 4.2 Hz), 2.68e2.30 (m, 6H), 1.63e1.41 (m, 2H),
1.44e1.22 (m, 6H), 0.98 (d, 3H, J¼6.9 Hz), 0.89 (t, 3H, J¼6.9 Hz); 13C
4.4.3. Cholest-5-en-3-ol
(3b
)-(O-phenyl
carbonothioate)
NMR (75 MHz, CDCl3)
d 75.2, 72.1, 42.4, 36.1, 32.8, 31.6, 30.8, 29.8,
(5c).10b This compound was obtained from cholesterol in 100%