Felpin and Lebreton
tion by flash chromatography (20% ethyl acetate-hexane) gave
0.25 mol). After the mixture was stirred at 50 °C for 12 h,
another portion of methylamine (11 mL, 0.13 mol) was added,
and the resulting mixture was stirred for 8 h at 50 °C. Then,
the mixture was diluted with ether (100 mL) and water (30
mL). The aqueous phase was extracted with ether (4×). The
combined extracts were washed with water (1×) and brine
(2×), dried over anhydrous MgSO4, and filtered. Removal of
solvent left an oil which was purified by flash chromatography
(5% EtOH/0.5% Et3N/CH2Cl2), affording 16 (1.85 g, 88%) as a
5 (1.32 g, 77%) as a colorless oil: [R]20 ) -63.5 (c 2.36, CH2-
D
Cl2); IR (KBr) ν 2919, 3061, 3425 cm-1; 1H NMR δ (ppm) 1.81
(ddd, 1H, J ) 3.7 Hz, J ) 6.7 Hz, J ) 14.5 Hz), 2.16 (ddd, 1H,
J ) 4.1 Hz, J ) 9.0 Hz, J ) 14.5 Hz), 2.51 (s br, 1H), 2.62 (dd,
1H, J ) 2.9 Hz, J ) 4.9 Hz), 2.85 (t app, 1H, J ) 4.7 Hz),
3.14-3.23 (m, 1H), 4.95 (dd, 1H, J ) 3.5 Hz, J ) 9 Hz), 7.27-
7.40 (m, 5H); 13C NMR δ (ppm) 41.5, 47.2, 50.1, 71.8, 125.7,
127.7, 128.6, 144.2; HRMS (CI/NH3) m/z calcd for C10H16NO2
(M + NH4+) 182.1181, found 182.1177.
colorless oil: [R]20 ) -50 (c 2.68, CH2Cl2); IR (KBr) ν 1641,
D
2955, 3064, 3367 cm-1; H NMR δ (ppm) -0.22 (s, 3H), 0.04
1
(1S,3S)-ter t-Bu tyldim eth yl(2-oxir an yl-1-ph en yleth oxy)-
sila n e (13). To a solution of epoxy alcohol 5 (1.32 g, 8.05 mmol)
in DMF (25 mL) at room temperature were added Et3N (2.24
mL, 16.1 mmol), TBDMSCl (1.94 g, 12.9 mmol), and DMAP
(50 mg). After being stirred at room temperature for 3 h, the
resulting mixture was diluted with ether (75 mL) and quenched
with water (50 mL). The aqueous phase was extracted with
ether (4×). The combined extracts were washed with brine
(3×), dried over anhydrous MgSO4, and filtered. Removal of
solvent left an oil which was purified by flash chromatography
(2% ethyl acetate/hexane), affording 13 (2.15 g, 96%) as a
(s, 3H), 0.90 (s, 9H), 1.46-1.67 (m, 4H), 1.80-1.95 (m, 1H),
2.01-2.12 (m, 2H), 2.36 (s, 3H), 2.50-2.62 (m, 1H), 4.76 (dd,
1H, J ) 4.1 Hz, J ) 8.7 Hz), 4.91-5.07 (m, 2H), 5.72-5.93
(m, 1H), 7.22-7.33 (m, 5H); 13C NMR δ (ppm) -4.9, -4.5, 18.1,
25.9, 29.8, 32.9, 33.4, 45.2, 57.1, 74.6, 114.4, 125.9, 127.1, 128.2,
138.8, 145.7; HRMS (CI/NH3) m/z calcd for C20H36NOSi (M +
H+) 334.2566, found 334.2552.
(2′S,3S)-{1-[2-(ter t-Bu t yld im et h ylsila n oxy)-2-p h en yl-
eth yl]p en t-4-en yl}m eth ylca r ba m ic Acid ter t-Bu tyl Ester
(17). A solution of amine 16 (1.85 g, 5.56 mmol) and Et3N (1.16
mL, 8.33 mmol) in CH2Cl2 (100 mL) at room temperature was
treated with (Boc)2O (1.82 g, 8.33 mmol). The mixture was
stirred for 6 h at room temperature, and then the solvent was
evaporated under reduced pressure. The residue was diluted
in EtOH (50 mL) and treated with imidazole (1.89 g, 27.8
mmol). After the resulting mixture was stirred for 15 min at
room temperature, the solvent was evaporated and the residue
was diluted with CH2Cl2 (50 mL) and washed with 0.5% HCl
solution. The organic extract was dried over anhydrous MgSO4,
filtered, and concentrated in vacuo. Purification by flash
chromatography (5% ethyl acetate/hexane) gave 17 (2.28 g,
colorless oil: [R]20 ) -69.5 (c 1.68, CH2Cl2); IR (KBr) ν 2955,
D
3033 cm-1; H NMR δ (ppm) -0.12 (s, 3H), 0.08 (s, 3H), 0.91
1
(s, 9H), 1.66 (ddd, 1H, J ) 3.4 Hz, J ) 7.2 Hz, J ) 14 Hz),
1.96 (ddd, 1H, J ) 4.4 Hz, J ) 9.1 Hz, J ) 14 Hz), 2.45 (dd,
1H, J ) 2.8 Hz, J ) 5.0 Hz), 2.80 (t, 1H, J ) 9 Hz), 3.11-3.20
(m, 1H), 4.92 (dd, 1H, J ) 3.4 Hz, J ) 9.3 Hz), 7.22-7.34 (m,
5H); 13C NMR δ (ppm) -5.0, -4.5, 18.3, 25.9, 44.5, 47.9, 49.9,
72.8, 125.7, 127.3, 128.3, 145.2. Anal. Calcd for C16H26O2Si:
C, 69.01; H, 9.41. Found: C, 69.12; H, 9.33.
(1S,3R)-1-(ter t-Bu tyld im eth ylsila n oxy)-1-p h en ylh ep t-
6-en -3-ol (14). To a solution of CuI (207 mg, 1.09 mmol) in
ether (4 mL) cooled at -40 °C was added AllMgBr (1 M in
ether, 10.85 mL, 10.85 mmol). The resulting mixture was
stirred at -30 °C for 15 min, and a solution of epoxide 13 (2.01
g, 7.23 mmol) in ether (14 mL) was added. After being stirred
at -40 °C for 30 min, the reaction was quenched with
saturated NH4Cl solution and extracted with ether (4×). The
combined extracts were washed with brine, dried over anhy-
drous MgSO4, filtered, and concentrated in vacuo. Purification
by flash chromatography (5% ethyl acetate/hexane) gave 14
95%) as a colorless oil: [R]20 ) -35.7 (c 2.74, CH2Cl2); IR
D
(KBr) ν 1642, 1695, 2956, 3065 cm-1; H NMR (two rotamers
1
in a 7/3 ratio) δ (ppm) -0.19 (s, 3H), 0.02 (s, 3H), 0.87 (s, 9H),
1.43 (s, 9H × 0.7), 1.49 (s, 9H × 0.3), 1.66-2.08 (m, 6H), 2.66
(s, 3H × 0.3), 2.71 (s, 3H × 0.7), 3.87 (m, 1H), 4.57 (t, 1H, J )
6.9 Hz), 4.89-4.99 (m, 2H), 5.65-5.85 (m, 1H), 7.27-7.30 (m,
5H); 13C NMR (two rotamers) δ (ppm) -4.9, -4.5, 18.2, 25.9,
28.6, 30.4, 32.0, 44.2, 51.6, 51.9, 72.8, 72.9, 79.0, 79.6, 114.8,
126.5, 127.3, 128.2, 138.1, 138.3, 144.8, 145.2, 155.9, 156.2;
HRMS (CI/i-butane) m/z calcd for C25H44NO3Si (M + H+)
434.3090, found 434.3088. Anal. Calcd for C25H43NO3Si: C,
69.23; H, 9.99; N, 3.23. Found: C, 69.16; H, 10.05; N, 3.21.
(2.13 g, 92%) as a colorless oil: [R]20 ) -63.3 (c 2.21, CH2-
D
Cl2); IR (KBr) ν 1641, 2954, 3065, 3447 cm-1; 1H NMR δ (ppm)
-0.09 (s, 3H), 0.09 (s, 3H), 0.93 (s, 9H), 1.34-1.66 (m, 2H),
1.73-1.93 (m, 2H), 1.95-2.19 (m, 2H), 3.72-3.84 (m, 1H),
4.88-5.03 (m, 2H), 5.10 (t app, 1H, J ) 5.3 Hz), 5.69-5.89
(m, 1H), 7.23-7.36 (m, 5H); 13C NMR δ (ppm) -5.1, -4.6, 18.3,
26.0, 30.0, 36.9, 46.1, 67.9, 73.8, 114.7, 125.8, 127.2, 128.3,
138.7, 144.3; HRMS (CI/i-butane) m/z calcd for C19H33O2Si (M
+ H+) 321.2250, found 321.2264. Anal. Calcd for C19H32O2Si:
C, 71.19; H, 10.06. Found: C, 71.14; H, 10.15.
(2′S,3S)-{1-[2-(ter t-Bu t yld im et h ylsila n oxy)-2-p h en yl-
eth yl]-5-h yd r oxyp en tyl}m eth ylca r ba m ic Acid ter t-Bu tyl
Ester (18). To a solution of cyclohexene (2.75 mL, 27.2 mmol)
was added BH3‚Me2S (2 M in THF, 6.87 mL, 13.7 mmol) at 0
°C. The mixture was stirred for 1 h at 0 °C, and then a solution
of carbamate 17 (1.95 g, 4.50 mmol) in THF (70 mL) was slowly
added over 10 min at 0 °C. The solution was allowed to warm
to room temperature, stirred for 6 h, cooled to 0 °C, quenched
with EtOH (5 mL), and treated with 1 M aqueous NaOH
solution (22.5 mL, 22.5 mmol) and H2O2 (50% in water, 5.52
mL, 90 mmol). After being stirred at room temperature for 1
h, the resulting mixture was quenched with 1 M aqueous
Na2S2O3 solution. The aqueous phase was extracted with
AcOEt (4×). The combined organic extracts were washed with
1 M Na2S2O3 solution (1×) and brine (1×), dried over anhy-
drous MgSO4, filtered, and concentrated under reduced pres-
sure. The volatile residues were eliminated by bulb to bulb
distillation (6 mmHg, 70 °C), and the residue was purified by
flash chromatography (20% ethyl acetate/hexane) to give 18
(2′S,1R)-Meth a n esu lfon ic Acid 1-[2-(ter t-Bu tyld im eth -
ylsila n oxy)-2-p h en yleth yl]p en t-4-en yl Ester (15). A solu-
tion of alcohol 14 (2.10 g, 6.56 mmol) and Et3N (1.83 mL, 13.1
mmol) in CH2Cl2 (65 mL) at 0 °C was treated with MsCl (0.76
mL, 9.8 mmol). The resulting mixture was stirred at 0 °C for
10 min and then washed with water (3×). The organic phase
was dried over anhydrous MgSO4, filtered, and concentrated
under reduced pressure. The residue was purified by flash
chromatography (5% ethyl acetate/hexane) to give 15 (2.53 g,
97%) as a colorless oil: [R]20 ) -41.5 (c 2.61, CH2Cl2); IR
D
(KBr) ν 1642, 2955, 3031 cm-1
;
1H NMR (200 MHz, CDCl3) δ (ppm) -0.26 (s, 3H), 0.10 (s,
3H), 0.88 (s, 9H), 1.81-1.94 (m, 2H), 1.99-2.06 (m, 2H), 2.11-
2.23 (m, 2H), 3.01 (s, 3H), 4.84 (dd, 1H, J ) 4.3 Hz, J ) 7.8
Hz), 4.92-5.11 (m, 3H), 5.70-5.90 (m, 1H), 7.25-7.34 (m, 5H);
13C NMR δ (ppm) -5.0, -4.4, 18.1, 25.9, 28.9, 34.7, 39.0, 46.0,
71.9, 80.8, 115.6, 126.1, 127.6, 128.3, 137.0, 144.6.
(1.83 g, 90%) as a colorless oil: [R]20 ) -31.5 (c 2.13, CH2-
D
Cl2); IR (KBr) ν 1694, 2929, 3064, 3438 cm-1; H NMR (two
1
rotamers) δ (ppm) -0.18 (s, 3H), 0.02 (s, 3H), 0.88 (s, 9H),
1.19-2.12 (m, 8H), 1.43 (s, 9H × 0.7), 1.49 (s, 9H × 0.3), 2.66
(s, 9H × 0.3), 2.70 (s, 9H × 0.7), 3.56 (q app, 2H, J ) 6.6 Hz),
3.86 (m, 1H × 0.7), 4.00 (m, 1H × 0.3), 4.57 (t, 1H, J ) 7 Hz),
7.29-7.33 (m, 5H); 13C NMR (two rotamers in a 7/3 ratio) δ
(ppm) -4.9, -4.5, 18.2, 22.0, 22.4, 25.9, 28.6, 32.1, 32.4, 32.6,
44.2, 51.3, 52.1, 62.7, 72.8, 73.0, 79.1, 79.6, 126.5, 127.2, 127.3,
(2′S,3S)-{1-[2-(ter t-Bu t yld im et h ylsila n oxy)-2-p h en yl-
eth yl]p en t-4-en yl}m eth yla m in e (16). To a solution of me-
sylate 15 (2.53 g, 6.36 mmol) in DMF (30 mL) at room
temperature was added methylamine (40% in water, 22 mL,
9198 J . Org. Chem., Vol. 67, No. 26, 2002