12534 J. Am. Chem. Soc., Vol. 118, No. 50, 1996
Guindon et al.
7.42 (m, 5H); 13C NMR (50.3 MHz, CDCl3) δ 33.34, 51.56, 52.99,
56.76, 84.99, 116.86, 127.66, 128.37, 128.52, 134.44, 138.81, 174.44;
IR (neat) 2980, 1740, 1650, 1440, 1170, 1100, 790 cm-1; MS (FAB)
235, 202 (10), 171 (15), 143 (20), 121 (100); HRMS calcd for C14H19O3
(MH) 235.1334, found 235.1341; Anal. Calcd for C14H18O3: C, 71.77;
H, 7.74. Found: C, 71.50; H, 7.68.
Methyl (2S*, 3R*)-2-[Propen-3-yl]-3-methoxybutanoate (13).
Colorless oil; 1H NMR (200 MHz, CDCl3) δ 1.14 (d, J ) 6.2 Hz, 3H),
2.20-2.28 (m, 1H), 2.30-2.38 (m, 1H), 2.58 (ddd, J ) 5.6, 7.6, 8.8
Hz, 1H), 3.29 (s, 3H), 3.50 (dd, J ) 6.2, 7.6 Hz, 1H), 3.66 (s, 3H),
4.96-5.09 (m, 2H), 5.62-5.82 (m, 1H); 13C NMR (50.3 MHz, CDCl3)
δ 16.19, 32.17, 51.45, 51.54, 56.62, 77.44, 116.73, 135.13, 174.20; IR
(neat) 2840, 1735, 1640, 1435, 1375, 1100, 990 cm-1; MS (FAB) 249
(MH + C3H8S, 100), 173 (MH, 40), 141 (39), 127 (16), 115 (32);
HRMS calcd for C9H17O3 (MH) 173.1178, found 173.1170.
2920, 2800, 1720, 1415, 1140, 1065 cm-1; MS (FAB) 199 (MH, 100),
185 (19), 167 (47), 137 (35); HRMS calcd for C11H21O3 (MH) 199.1334,
found 199.1323.
Methyl (2S*, 3R*)-3-[Tetrahydrofuran-2-yl]-2-[propen-3-yl]-pro-
1
panoate (34). Colorless oil; H NMR (400 MHz, CDCl3) δ 1.51-
1.59 (m, 1H), 1.80-1.93 (m, 2H), 1.98-2.05 (m, 1H), 2.16-2.22 (m,
1H), 2.30-2.37 (m, 1H), 2.47-2.55 (m, 1H), 3.68 (s, 3H), 3.71-3.76
(m, 1H), 3.80-3.88 (m, 1H), 3.97-4.02 (m, 1H), 4.97-5.09 (m, 2H),
5.65-5.77 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 25.45, 29.52, 33.31,
51.20, 51.43, 67.91, 79.66, 116.72, 134.70, 174.20; IR (neat) 2950,
2880, 1745, 1440, 1200, 1170, 1070 cm-1; MS 185 (MH, 2), 143 (12),
111 (7), 71 (100); HRMS calcd for C10H17O3 (MH) 185.1178, found
185.1167.
Methyl (2S*, 3R*)-2-[2-Phenylselenyl-3-trimethylsilylpropanyl]-
3-methoxy-3-phenylpropanoate (57). To a suspension of MgBr2‚OEt2
(51.6 mg, 0.20 mmol) in CH2Cl2 (1 mL) at -78 °C was added dropwise
a solution of phenylselenide 37 (54.5 mg, 0.20 mmol) in CH2Cl2 (1
mL). Allyltrimethylsilane (0.065 mL, 0.40 mmol) and Et3B (0.04 mL
of a 1.0 M solution in hexanes) were added to the mixture after stirring
for 10 min at -78 °C. The resulting suspension was stirred for an
additional 6 h at this temperature, and then 0.2 equiv of Et3B were
added each hour until the reaction was judged to be complete by TLC.
The reaction mixture was then poured into saturated NaHCO3 and
extracted with CH2Cl2. The combined organic extracts were washed
with brine, dried over MgSO4, filtered, and concentrated under reduced
pressure. The crude product was carefully purified by flash chroma-
tography (CH2Cl2) using silica neutralized with Et3N to afford the anti
product 57 (46.4 mg, 50%). Colorless oil; 1H NMR (300 MHz, CDCl3)
δ -0.04 (s, 9H), 0.74 (dd, J ) 9.9, 9.9 Hz, 1H), 1.08 (dd, J ) 4.8, 4.8
Hz, 1H), 1.22 (m, 1H), 1.79 (m, 1H), 3.87-3.96 (m, 1H), 3.14 (s, 3H),
3.32 (td, J ) 3.0, 9.8 Hz, 1H), 3.75 (s, 3H), 4.23 (d, J ) 9.8 Hz, 1H),
7.10-7.40 (m, 10H); 13C NMR (100 MHz, CDCl3) δ 26.34, 36.62,
40.21, 51.60, 52.08, 56.68, 85.07, 127.48, 127.72, 128.24, 128.48,
134.34, 136.10, 138.78, 174.83; IR (neat) 3060, 2950, 1732, 1580, 1435,
1370, 1250, 1165, 845 cm-1; MS (FAB) 463.3 (MH, 8), 433.3 (94),
307.4 (46), 275 (36), 143 (80), 121 (100); HRMS calcd for C23H33O3-
SeSi (MH) 464.1286, found 464.1309.
Methyl (2S*, 3R*)-2-Propyl-3-methoxy-3-phenylpropanoate (58).
To a suspension of MgBr2‚OEt2 (194 mg, 0.75 mmol) in CH2Cl2 (5
mL) at -78 °C was added dropwise a solution of bromide 36 (202
mg, 0.738 mmol) in CH2Cl2 (1.5 mL). Allyltrimethylsilane (0.235 mL,
1.48 mmol) and Et3B (0.150 mL of a 1.0 M solution in hexanes) were
added to the mixture after stirring for 10 min at -78 °C. The resulting
suspension was stirred for an additional 1.5 h at this temperature, and
then tributyltin hydride (0.20 mL, 0.75 mmol) was added to the reaction
mixture. Subsequently 0.2 equiv of Et3B were added each hour until
the reaction was judged to be complete by TLC. The reaction mixture
was then poured into saturated NaHCO3 and extracted with CH2Cl2.
The combined organic extracts were washed with brine, dried over
MgSO4, filtered, and concentrated under reduced pressure. The crude
product was purified by flash chromatography (CH2Cl2) to afford the
anti product (87.8 mg, 39%). Colorless oil; 1H NMR (300 MHz,
CDCl3) δ -0.12 (s, 9H), 0.27-0.38 (m, 2H), 0.96-1.17 (m, 3H), 1.46-
1.55 (m, 1H), 2.68-2.78 (m, 1H), 3.13 (s, 3H), 3.77 (s, 3H), 4.23 (d,
J ) 10 Hz, 1H), 7.29-7.40 (m, 5H); 13C NMR (100 MHz, CDCl3) δ
16.18, 21.47, 32.63, 51.48, 52.96, 56.60, 85.46, 127.57, 128.13, 128.35,
139.09, 175.39; IR (neat) 3028, 2950, 1739, 1494, 1248, 1164, 1103
cm-1; MS (FAB) 308.9 (MH, 29), 276.9 (35), 145 (71), 121 (100);
HRMS calcd for C17H29O3Si (MH) 309.1886, found 309.1869; Anal.
Calcd for C17H20O3Si: C, 66.19; H, 9.15. Found: C, 66.42; H, 8.88.
Methyl (2S*, 3R*)-2-[Propen-3-yl]-3-methoxy-3-cyclohexylpro-
1
panoate (16). Colorless oil; H NMR (200 MHz, CDCl3) δ 1.13-
1.28 (m, 5H), 1.47 (s, 1H), 1.65-1.72 (m, 5H), 2.17-2.25 (m, 1H),
2.30-2.38 (m, 1H), 2.71 (ddd, J ) 5.0, 7.9, 9.7 Hz, 1H), 3.16 (s, 3H),
3.67 (s, 3H), 5.00 (d, J ) 10.1 Hz, 1H), 5.06 (m, 2H), 5.73 (m, 1H);
13C NMR (50.3 MHz, CDCl3) δ 26.20, 26.41, 26.58, 30.45, 33.29,
40.50, 48.11, 51.42, 61.06, 86.72, 116.77, 135.17, 174.60; IR (neat)
2920, 1740, 1440, 1170, 1110 cm-1; MS (CI,CH4) 241 (MH+, 53),
209 (100), 177 (27), 149 (49), 127 (21); HRMS calcd for C14H25O3
(MH) 241.1804, found 241.1794.
Methyl (2S*, 3R*)-2-[Propen-3-yl]-3-methoxy-4-methylpen-
tanoate (19). Colorless oil; 1H NMR (200 MHz, CDCl3) δ 0.89 (d, J
) 6.8 Hz, 3H), 0.99 (d, J ) 6.8 Hz, 3H), 1.86 (m, 1H), 2.16-2.24 (m,
1H), 2.31-2.39 (m, 1H), 2.64 (ddd, J ) 5.0, 8.1, 9.7 Hz, 1H), 3.20
(dd, J ) 3.9, 8.1 Hz, 1H), 3.40 (s, 3H), 4.15 (q, J ) 7.1 Hz, 2H),
4.97-5.10 (m, 2H), 5.64-5.80 (m, 1H); 13C NMR (50.3 MHz, CDCl3)
δ 14.31, 16.04, 20.18, 30.16, 33.37, 48.84, 60.21, 61.11, 86.92, 116.75,
135.10, 174.10; IR (neat) 2980, 1740, 1650, 1470, 1380, 1180, 1100,
920 cm-1; MS (CI, CH4) 215 (MH+, 81), 197 (18), 183 (95), 169 (70),
149 (23), 137 (29), 129 (20), 109 (100); HRMS calcd for C11H21O3
(MH) 201.1491, found 201.1495.
Methyl (2S*, 3R*)-2-[Propen-3-yl]-2-methyl-3-methoxy-3-phen-
ylpropanoate (22). Colorless oil; 1H NMR (400 MHz, CDCl3) δ 1.04
(s, 3H), 1.72 (dd, J ) 7.6, 13.3 Hz, 1H), 2.45 (dd, J ) 7.0, 13.5 Hz,
1H), 3.16 (s, 3H), 3.71 (s, 3H), 4.48 (s, 1H), 4.92-5.00 (m, 2H), 5.54-
5.60 (m, 1H), 7.25-7.35 (m, 5H); 13C NMR (100 MHz, CDCl3) δ
14.85, 41.10, 51.62, 52.06, 57.18, 88.00, 118.16, 127.78, 128.43, 133.12,
137.04, 175.70; IR (neat) 2980, 2840, 1745, 1460, 1220, 1100, 940
cm-1; MS (FAB) 249 (MH, 12), 217 (10), 189 (8), 157 (43), 121 (100);
HRMS calcd for C15H21O3 (MH) 249.1491, found 249.1503.
Methyl (2S*, 3R*)-2-[Propen-3-yl]-2-methyl-3-methoxybutanoate
1
(25). Colorless oil; H NMR (400 MHz, CDCl3) δ 1.10 (d, J ) 6.3
Hz, 3H), 1.12 (s, 3H), 1.28 (t, J ) 7.1 Hz, 3H), 2.04 (dd, J ) 7.5, 13.5
Hz, 1H), 2.34 (dd, J ) 7.1, 13.5 Hz, 1H), 3.31 (s, 3H), 3.60 (q, J )
6.3 Hz, 1H), 4.12-4.22 (m, 2H), 5.03-5.08 (m, 2H), 5.65-5.75 (m,
1H); 13C NMR (100 MHz, CDCl3) δ 12.54, 14.16, 15.04, 40.70, 56.94,
60.10, 81.03, 117.78, 133.53, 175.17; IR (neat) 2983, 2937, 1723, 1464,
1383, 1236 cm-1; MS (FAB) 201 (MH, 100), 169 (83), 141 (37), 132
(87), 129 (37); HRMS calcd for C11H21O3 (MH) 201.1491, found
201.1499.
Methyl (2S*, 3R*)-2-[Propen-3-yl]-2, 4-dimethyl-3-methoxypen-
1
tanoate (28). Colorless oil; H NMR (400 MHz, CDCl3) δ 1.02 (t, J
) 7.4 Hz, 3H), 1.10 (s, 3H), 1.26 (t, J ) 7.1 Hz, 3H), 1.38-1.55 (m,
2H), 2.05 (dd, J ) 7.5, 13.5 Hz, 1H), 2.38 (dd, J ) 7.1, 13.3 Hz, 1H),
3.30-3.34 (m, 1H), 3.40 (s, 3H), 4.10-4.17 (m, 2H), 5.00-5.05 (m,
2H), 5.64-5.71 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 11.66, 14.16,
16.04, 23.70, 40.48, 51.14, 60.14, 60.87, 88.06, 117.73, 133.74, 175.36;
IR (neat) 2980, 2810, 1720, 1450, 1210, 1090 cm-1; MS (FAB) 215
(MH, 100), 183 (37), 169 (33), 109 (53); HRMS calcd for C12H23O3
(MH) 215.1647, found 215.1633; Anal. Calcd for C12H22O3: C, 67.26;
H, 10.35. Found: C, 67.12; H, 10.13.
Methyl (2S*, 3R*)-3-[Tetrahydropyran-2-yl]-2-[propen-3-yl]-
propanoate (31). Colorless oil; 1H NMR (400 MHz, CDCl3) δ 1.27-
1.37 (m, 1H), 1.46-1.61 (m, 3H), 1.67-1.76 (m, 1H), 1.84-1.89 (m,
1H), 2.27-2.33 (m, 1H), 2.37-2.41 (m, 1H), 2.50-2.58 (m, 1H), 3.36-
3.51 (m, 2H), 3.69 (s, 3H), 3.93-3.99 (m, 1H), 4.99-5.11 (m, 2H),
5.69-5.77 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 23.08, 25.64, 28.88,
32.16, 51.08, 51.42, 68.46, 78.18, 116.51, 134.81, 174.21; IR (neat)
General Procedure for the Allylation of r-Iodoesters. Com-
pounds 11, 14, 17, 20, 23, 26, 29, 32, and 35: To a solution of iodide
9 (83.2 mg, 0.259 mmol) in CH2Cl2 (2.5 mL) at -78 °C were added
allyltributyltin (0.08 mL, 0.52 mmol) and Et3B (55 µL of a 1.0 M
solution in hexanes). The reaction mixture was then stirred for an
additional 3 h at this temperature. After concentration, the residue was
purified by flash chromatography (CH2Cl2) to afford the desired syn
adduct 11.
Methyl (2R*,3R*)-2-[Propen-3-yl]-3-methoxy-3-phenylpropanoate
(11). Colorless oil; 1H NMR (200 MHz, CDCl3) δ 2.46-2.52 (m, 1H),
2.61-2.68 (m, 1H), 2.81 (ddd, J ) 3.8, 8.4, 10.1 Hz, 1H), 3.19 (s,
3H), 3.40 (s, 3H), 4.27 (d, J ) 8.6 Hz, 1H), 4.97-5.11 (m, 2H), 5.66-
5.78 (m, 1H), 7.25-7.37 (m, 5H); 13C NMR (50.3 MHz, CDCl3) δ