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P. Harsh, G.A. O’Doherty / Tetrahedron 65 (2009) 5051–5055
6.6 Hz, 1H), 5.87 (dddd, J¼17.4, 10.2, 7.2, 7.2 Hz, 1H), 5.19 (m, 2H),
4.5.2. (1R,20R,30R)-(30-Phenyloxiran-20-yl)but-3-enyl acrylate (4b)
Rf¼0.58 (8:2 (v/v) hexanes/EtOAc); IR (neat, cmꢂ1) 1731, 1406,
4.37 (dd, 6.6, 6.6 Hz, 1H), 2.42 (m, 2H), 1.85 (s, 1H); 13C NMR (CDCl3,
600 MHz):
d
136.6, 134.0, 131.5, 130.4, 128.5, 127.6, 126.4,118.5, 71.7,
1373, 1240, 1186, 1046, 984; 1H NMR (CDCl3, 270 MHz):
d 7.29 (m,
42.0; HRMS (CI) calcd for [C12H14OþNa]þ: 197.0945, found:
5H), 6.48 (dd, J¼17.3, 1.5 Hz, 1H), 6.17 (dd, J¼17.0, 7.0 Hz, 1H), 5.83
(m, 2H), 5.14 (m, 2H), 4.98 (dd, J¼12.6, 6.7, 1H), 3.79 (d, J¼2.0 Hz,
1H), 3.17 (dd, J¼5.9, 2.0 Hz, 1H), 2.54 (m, 2H); 13C NMR (CDCl3,
197.0942.
600 MHz):
d 165.6, 136.5, 132.4, 131.6, 128.7, 128.6, 128.4, 125.8,
119.1, 73.1, 62.7, 56.7, 36.2; HRMS (CI) calcd for [C15H16OþH]þ:
4.4. (1R,20S,30S)-(30-Phenyloxiran-20-yl)but-3-en-1-ol (5b)
245.1178, found: 245.1182.
To a solution of product (1R,E)-1-phenylhexa-1,5-dien-3-ol 6
(150 mg, 0.861 mmol) in 7 mL of benzene was added VO(acac)2
4.6. (3R,E)-1-Phenylhexa-1,5-dien-3-yl acrylate (9)
(3 mg, 12 mmol) to produce a green colored solution. After 10 min of
To a solution of product 6 (100 mg, 0.573 mmol) in 7 mL of
CH2Cl2 were added acrylic acid (82 mg, 1.14 mmol), DCC (236 mg,
1.14 mmol), and DMAP (4 mg) at room temperature. After stirring
for 6 h the reaction mixture was diluted with ether, passed through
Celite, and extracted with 1 M aqueous NaHSO4 and then satd
aqueous NaHCO3. The combined organic layers were washed with
brine, dried over anhydrous Na2SO4, and concentrated. Flash
chromatography on silica gel (9.5:0.5 (v/v) hexanes/EtOAc) pro-
vided compound 9 (92 mg, 70% yield) as a colorless oil with spectral
data that matched the reported data:1 1H NMR (600 MHz, CDCl3):
stirring, t-BuOOH (85 mg, 0.947 mmol) was added to the solution,
which was accompanied by a color change to a pale yellow/orange
color. The reaction was quenched with a satd NaHCO3 aqueous
solution. The layers were separated. The aqueous layer was
extracted with EtOAc and the combined organic layers were
washed with brine, dried over anhydrous Na2SO4, and concentrated
to afford crude product. Flash chromatography on silica gel (9:1
(v/v) hexane/EtOAc) provided compound 5b (119 mg, 71% yield) as
a colorless oil. Spectral data gave a satisfactory match to previous
reports.16 Rf¼0.3 (8:2 (v/v) hexanes/EtOAc); [
a]
D
25 26 (c 0.4, CHCl3);
d
7.41–7.25 (m, 5H), 6.92 (dt, 1H, J¼9.5 and 4.0 Hz), 6.72 (d, 1H,
IR (neat, cmꢂ1) 3439, 1642, 917; 1H NMR (CDCl3, 270 MHz):
d 7.32
J¼15.9 Hz), 6.27 (dd, 1H, J¼15.9 and 6.2 Hz), 6.08 (d, 1H, J¼9.5 Hz),
(m, 5H), 5.90 (ddt, J¼16.8, 10.2, 7.2, 7.2 Hz, 1H), 5.17 (m, 2H), 3.99
(dddd, J¼4.8, 4.8, 4.0, 4.0 Hz, 1H), 3.97 (d, J¼1.8 Hz, 1H), 3.10 (dd,
J¼3.0, 1.8 Hz, 1H), 2.35(m, 2H), 2.03 (m, 1H); 13C NMR (CDCl3,
5.10 (q, 1H, J¼6.9 Hz), 2.56–2.52 (m, 2H); 13C NMR (125 MHz,
CDCl3):
d 163.5, 144.5, 135.5, 132.8, 128.5 (2C), 128.1 (2C), 126.4,
125.5, 121.4, 77.8, 29.8.
600 MHz):
d 136.8, 133.4, 128.5, 128.3, 125.7, 118.4, 68.3, 64.2, 55.0,
37.9; HRMS (CI) calcd for [C12H14O2þNa]þ: 213.0894, found:
4.7. (1R,20R,30R)-(30-Phenyloxiran-20-yl)but-3-enyl
acrylate (4b)
213.0892.
To a solution of 3b (120 mg, 0.629 mmol) in 10 mL of CH2Cl2
were added acrylic acid (188 mg, 2.61 mmol), DCC (538 mg,
2.61 mmol), and DMAP (4 mg) at room temperature. After stirring
for 6 h the reaction mixture was diluted with ether, passed through
Celite, and extracted with 1 M aqueous NaHSO4 and then satd
aqueous NaHCO3. The combined organic layers were washed with
brine, dried over anhydrous Na2SO4, and concentrated. Flash
chromatography on silica gel (9.5:0.5 (v/v) hexanes/EtOAc) pro-
vided compound 4b (92.2 mg, 60% yield) as a colorless oil.
4.5. (1R,20S,30S)-(30-Phenyloxiran-20-yl)but-3-enyl acrylate
and (1R,20R,30R)-(30-phenyloxiran-20-yl)but-3-enyl acrylate
(4a/4b)
A
solution of product (1R,E)-1-phenylhexa-1,5-dien-3-ol 6
(150 mg, 0.861 mmol) in 5 mL of CH2Cl2 was cooled and stirred in
an ice bath at 0 ꢀC as a solution of m-CPBA (163 mg, 0.947 mmol) in
3 ml of CH2Cl2 was added dropwise. The mixture was washed with
10% Na2CO3 (2ꢁ5 ml) and brine (7 ml). The combined organic
layers were dried over anhydrous Na2SO4 and concentrated to af-
ford crude product. Flash chromatography on silica gel (9:1 (v/v)
hexane/EtOAc) provided compound 5a/5b (131 mg, 80% yield) as
a colorless oil. Rf¼0.3 (8:2 (v/v) hexanes/EtOAc). This mixture was
inseparable and used as is.
To a solution of 30-(phenyloxiran-20-yl)but-3-en-1-ol 5a/5b
(100 mg, 0.526 mmol) in 7 mL of CH2Cl2 was added acrylic acid
(75 mg, 1.05 mmol), DCC (217 mg, 1.05 mmol), and DMAP (4 mg) at
room temperature. After stirring for 6 h the reaction mixture was
diluted with ether, passed through Celite, and extracted with 1 M
aqueous NaHSO4 and then satd aqueous NaHCO3. The combined
organic layers were washed with brine, dried over anhydrous
Na2SO4, and concentrated. Flash chromatography on silica gel
(9.5:0.5 (v/v) hexanes/EtOAc) provided compound 4a/4b (90 mg,
70% yield, 1.5:1, 4a/4b) as a colorless oil.
4.8. (R)-(D)-Goniothalamin (3a)
To a solution of 9 (25 mg, 0.11 mmol) in 5 mL of CH2Cl2 was added
Grubbs (I) catalyst (9 mg, 0.011 mmol) at room temperature. Stirring
commenced for 4 h at reflux conditions and then the reaction mix-
ture was concentrated. Flash chromatography on silica gel (7:3 (v/v)
hexane/EtOAc) provided compound 3a (17 mg, 77% yield) as a dark
oil (note: color caused by Grubbs catalyst). Spectral data gave a sat-
25
isfactory match to previous reports. [
a]
þ165 (c 1.0, CHCl3); IR
D
(neat, cmꢂ1) 1724, 1610, 1241, 815; 1H NMR:
d 7.34 (m, 5H), 6.94 (ddd,
J¼9.7, 4.9, 3.7 Hz, 1H), 6.74 (d, J¼16 Hz, 1H), 6.30 (dd, J¼16, 6.5 Hz,
1H), 6.10 (ddd, J¼9.6, 1.7, 1.7 Hz, 1H), 5.10 (m, 1H), 2.59 (m, 2H); 13C
NMR: d 164.1,144.8,135.9,133.3,128.9,128.5,126.9,125.8,121.9, 78.1,
30.1; HRMS(CI) calcd for [C13H12O2þH]þ: 201.0916, found: 201.0920.
4.9. (R)-(D)-Goniothalamin oxide (3b)
4.5.1. (1R,20S,30S)-(30-Phenyloxiran-20-yl)but-3-enyl acrylate (4a)
25
Rf¼0.59 (8:2 (v/v) hexanes/EtOAc); [
a]
61 (c 0.4, CHCl3); IR
To a solution of 4a (25 mg, 0.10 mmol) in 7 mL of CH2Cl2 was
added Grubbs (I) catalyst (8 mg, 0.010 mmol) at room temperature.
After stirring for 4 h at reflux, the reaction mixture was concen-
trated. Flash chromatography on silica gel (7:3 (v/v) hexane/EtOAc)
provided compound 5 (17 mg, 77% yield) as a dark oil (note: color
D
(neat, cmꢂ1) 1731, 1240, 1186, 1046; 1H NMR (CDCl3, 600 MHz):
d
7.30 (m, 5H), 6.43 (dd, J¼17.3, 1.5 Hz, 1H), 6.12 (dd, J¼17.1, 10.4 Hz,
1H), 5.84 (m, 2H), 5.16 (m, 2H), 4.99 (ddd, J¼7.2, 5.2, 3.2 Hz, 1H),
3.94 (d, J¼2.0 Hz, 1H), 3.07 (dd, J¼5.7, 2.0 Hz, 1H), 2.57 (m, 2H); 13C
NMR (CDCl3, 600 MHz):
d
165.3, 136.6, 132.4, 131.3, 128.5, 128.3,
caused by Grubbs catalyst). Rf¼0.9 (8:2 (v/v) hexanes/EtOAc).
25
128.1, 125.6, 118.5, 72.1, 61.8, 57.3, 35.8; HRMS (CI) calcd for
Spectral data gave a satisfactory match to previous reports.17
[a]
D
[C15H16OþNa]þ: 267.0997, found: 267.0999.
þ100 (c 0.4, CHCl3); IR (neat, cmꢂ1) 1724, 1247, 1041, 815; 1H NMR