over 4 h, quenched with saturated aqueous ammonium chloride
(20 cm3) and extracted with diethyl ether (3 × 50 cm3). The
combined organic extracts were dried (MgSO4) and then evap-
orated in vacuo. Chromatography of the residue on silica gel
using diethyl ether–light petroleum (bp 40–60 ЊC) (1:1) as elu-
ent gave the alcohol (1.79 g, 99%) as a colourless oil; νmax(film)/
cmϪ1 3380, 2938, 2864, 1721, 1630, 1439, 1340, 1306, 1197,
1170, 1136 and 1058; δH(360 MHz; CDCl3) 6.05 (1H, d, J 1.3,
1284, 1255, 1196, 1170, 1130 and 1101; δH(360 MHz; CDCl3)
6.12 (1H, d, J 1.4, CHH᎐C), 5.82 (1H, t, J 7.3, CH᎐C(CO -
᎐
᎐
2
CH )), 5.51 (1H, d, J 1.4, CHH᎐C), 5.12 (1H, t, J 7.2, CH᎐
᎐
᎐
3
C(CH3)), 3.74 (3H, s, OCH3), 3.72 (3H, s, OCH3), 3.58 (2H, t,
J 6.2, CH O), 2.49 (2H, app. q, J 7.3, CH CH᎐C(CO CH )),
᎐
2
2
2
3
2.32 (2H, t, J 7.3, CH C(CH )᎐CH), 2.23 (2H, t, J 7.2, CH C-
᎐
2
3
2
(CO CH )᎐CH ), 2.15 (2H, app. q, J 7.2, CH CH᎐C(CH )),
᎐
᎐
2
3
2
2
3
2.06 (2H, t, J 7.6, CH C(CO CH )᎐CH), 1.57 (3H, s, CH᎐
᎐
3
᎐
2
2
CHH᎐C), 5.44 (1H, d, J 1.3, CHH᎐C), 5.06 (1H, t, J 7.3,
C(CH3)), 1.51–1.40 (4H, m), 0.87 (9H, s, C(CH3)3) and 0.03
(6H, s, Si(CH3)2); δC(90.6 MHz; CDCl3) 168.5 (s), 167.6 (s),
141.5 (d), 140.2 (s), 135.2 (s), 131.8 (s), 124.8 (t), 123.8 (d), 62.9
(t), 51.7 (q), 51.1 (q), 39.1 (t), 34.2 (t), 32.3 (t), 32.0 (t), 27.9 (t),
26.7 (t), 25.9 (3 × q), 25.3 (t), 18.3 (s), 15.9 (q) and Ϫ5.3 (2 ×
q); m/z (EI) 395.2264 (Mϩ Ϫ C(CH3)3, C21H35O5Si requires
395.2254).
The (E,E)-isomer eluted second (892 mg, 31%) as a colour-
less oil; νmax(film)/cmϪ1 2951, 2929, 2857, 1719, 1632, 1461,
1436, 1283, 1256, 1195, 1171, 1128 and 1101; δH(360 MHz;
᎐
᎐
CH᎐C(CH )), 3.66 (3H, s, OCH ), 3.50 (2H, t, J 6.6, CH O),
᎐
3
3
2
2.75–2.63 (1H, br s, OH), 2.48 (2H, t, J 7.4, CH2CH2CH2O),
2.09 (2H, app. q, J 7.3, CH CH᎐C(CH )), 1.96 (2H, t, J 7.3,
᎐
2
3
CH C᎐CH ), 1.60–1.54 (2H, m, CH CH O) and 1.51 (3H, s,
᎐
2
2
2
2
CH᎐C(CH )); δ (90.6 MHz; CDCl ) 167.6 (s), 139.9 (s), 135.4
᎐
3
C
3
(s), 124.8 (t), 123.2 (d), 62.1 (t), 51.5 (q), 35.6 (t), 31.7 (t), 30.5
(t), 26.5 (t) and 15.6 (q); m/z (EI) 212.1418 (Mϩ, C12H20O3
requires 212.1413).
CDCl ) 6.66 (1H, t, J 7.3, CH᎐C(CO CH )), 6.07 (1H, d, J 1.4,
᎐
(E)-8-Methoxycarbonyl-4-methylnona-4,8-dienal 25
3
2
3
CHH᎐C), 5.46 (1H, d, J 1.4, CHH᎐C), 5.09 (1H, t, J 7.2,
᎐
᎐
Dess–Martin periodinane oxidation of the alcohol 24 accord-
ing to the general procedure and using diethyl ether–light
petroleum (bp 40–60 ЊC) (1:3) as eluent gave the aldehyde (91%)
as a colourless oil; νmax(film)/cmϪ1 2951, 2722, 1722, 1631, 1440,
1389, 1306, 1248, 1197, 1170 and 1136; δH(360 MHz; CDCl3)
CH᎐C(CH )), 3.68 (3H, s, OCH ), 3.65 (3H, s, OCH ), 3.55
᎐
3
3
3
(2H, t, J 6.3, CH2O), 2.29–2.20 (6H, m), 2.14 (2H, app. q, J 7.2,
CH CH᎐C(CH )), 2.03 (2H, t, J 7.8), 1.54 (3H, s, CH᎐C(CH) ),
᎐
᎐
2
3
3
1.49–1.35 (4H, m), 0.82 (9H, s, C(CH3)3) and Ϫ0.02 (6H, s,
Si(CH3)2); δC(90.6 MHz; CDCl3) 167.4 (s), 165.6 (s), 142.1 (d),
139.9 (s), 134.6 (s), 132.1 (s), 124.7 (t), 124.0 (d), 62.8 (t), 51.5
(q), 51.3 (q), 38.4 (t), 32.5 (t), 31.8 (t), 26.9 (t), 26.6 (t), 26.4 (t),
25.8 (3 × q), 25.4 (t), 18.1 (s), 15.8 (q) and Ϫ5.5 (2 × q).
9.73 (1H, t, J 1.9, CHO), 6.12 (1H, d, J 1.4, CHH᎐C), 5.50 (1H,
᎐
d, J 1.4, CHH᎐C), 5.14 (1H, t, J 7.1, CH᎐C(CH )), 3.74 (3H, s,
᎐
᎐
3
OCH3), 2.52–2.48 (2H, m), 2.33–2.28 (4H, m), 2.18 (2H, app.
q, J 7.1, CH CH᎐C(CH )) and 1.56 (3H, s, CH᎐C(CH ));
᎐
᎐
2
3
3
δC(90.6 MHz; CDCl3) 202.3 (d), 167.4 (s), 139.8 (s), 133.8 (s),
124.9 (t), 124.1 (d), 51.5 (q), 41.9 (t), 31.7 (t), 31.5 (t), 26.5 (t)
and 15.9 (q).
(Z,E)-5,13-Bis(methoxycarbonyl)-9-methyltetradeca-5,9,13-
trien-1-ol 27
Tetrabutylammonium fluoride (3.5 cm3, 3.5 mmol, 1 M in
THF) was added dropwise over 5 min to a stirred solution of
the triene 26 (1.43 g, 3.16 mmol) in THF (15 cm3) at 0 ЊC. The
mixture was allowed to reach room temperature over 6 h,
quenched with saturated aqueous ammonium chloride (10 cm3)
and extracted with diethyl ether (3 × 50 cm3). The combined
organic extracts were dried (MgSO4) and then evaporated in
vacuo. Chromatography of the residue on silica gel using diethyl
ether–light petroleum (bp 40–60 ЊC) (3:2) as eluent gave the
alcohol (1.03 g, 96%) as a colourless oil; νmax(film)/cmϪ1 3425,
2948, 2861, 1714, 1631, 1438, 1377, 1306, 1198, 1170, 1133,
1060 and 1031; δH(360 MHz; CDCl3) 6.14 (1H, d, J 0.9,
Methyl 2-(dimethoxyphosphinyl)-6-{[dimethyl(1,1-dimethyl-
ethyl)silyl]oxy}hexanoate 31
Trimethyl phosphonoacetate (16.20 cm3, 18.24 g, 100 mmol)
was alkylated with 1-{[dimethyl(1,1-dimethylethyl)silyl]oxy}-4-
iodobutane6 (15.72 g, 25 mmol) according to the procedure
used for the formation of 10. Chromatography on silica gel
using ethyl acetate–light petroleum (bp 40–60 ЊC) (1:1 to 9:1)
as eluent gave the phosphonate (7.91 g, 86%) as a colourless oil;
νmax(film)/cmϪ1 3070, 3048, 2932, 2858, 1733, 1589, 1472, 1462,
1428, 1390, 1367, 1253, 1153, 1110, 1052 and 1028; δH(400
MHz; CDCl3) 3.73 (3H, d, JHP 6.7, (CH3O)P), 3.71 (3H, d, JPH
6.8, (CH3O)P), 3.69 (3H, s, OCH3), 3.52 (2H, t, J 6.3, CH2O),
2.91 (1H, ddd, J 3.8 and 11.0, JHP 22.6, CHP), 1.97–1.90 (1H,
m, CHHCHP), 1.81–1.75 (1H, m, CHHCHP), 1.49–1.41 (2H,
m), 1.39–1.28 (2H, m), 0.03 (9H, s, C(CH3)3) and Ϫ0.02 (6H, s,
Si(CH3)2); δC(67.8 MHz; CDCl3) 169.4 (s, JCP 4.9), 62.5 (t), 53.2
(q, JCP 6.1), 53.1 (q, JCP 7.3), 52.4 (q), 45.0 (d, JCP 131), 32.1 (t),
26.7 (3 × q), 25.8 (t), 24.7 (t, JCP 14.6), 18.2 (s) and Ϫ5.5 (2 × q);
m/z (EI) 353.1563 (Mϩ Ϫ CH3, C14H30O6PSi requires 353.1549).
CHH᎐C), 5.85 (1H, t, J 7.3, CH᎐C(CO CH )), 5.52 (1H, d,
᎐
᎐
2
3
J 0.9, CHH᎐C), 5.13 (1 H, t, J 7.1, CH᎐C(CH )), 3.75 (3H, s,
᎐
᎐
3
OCH3), 3.73 (3H, s, OCH3), 3.64 (2H, t, J 6.3, CH2O), 2.50 (2H,
app. q, J 7.3, CH CH᎐C(CO CH )), 2.33 (2H, t, J 7.3, CH -
᎐
2
2
3
2
C(CH )᎐CH), 2.26 (2H, t, J 7.1, CH C(CO CH )᎐CH ), 2.16
᎐
᎐
3
2
2
3
2
(2H, app. q, J 7.1, CH CH᎐C(CH )), 2.07 (2H, t, J 7.5, CH -
᎐
2
3
2
C(CO CH )᎐CH), 1.59 (3H, s, CH᎐C(CH )) and 1.55–1.45 (4H,
᎐
᎐
2
3
3
m); δC(90.6 MHz; CDCl3) 168.5 (s), 167.8 (s), 141.9 (d), 140.1
(s), 135.1 (s), 131.6 (s), 124.9 (t), 123.9 (d), 62.6 (t), 51.8 (q), 51.2
(q), 39.1 (t), 34.2 (t), 32.1 (t), 32.0 (t), 27.9 (t), 26.7 (t), 25.3 (t)
and 15.8 (q); m/z (EI) 306.1834 (Mϩ Ϫ CH3OH, C18H26O4
requires 306.1831).
(Z,E)-5,13-Bis(methoxycarbonyl)-1-{[dimethyl(1,1-dimethyl-
ethyl)silyl]oxy}-9-methyltetradeca-5,9,13-triene 26
A solution of the phosphonate 31 (2.58 g, 7.01 mmol) in THF
(5 cm3) was added dropwise over 10 min to a stirred slurry of
sodium hydride (280 mg, 7.0 mmol, 60% oil dispersion) in THF
(10 cm3) at 0 ЊC. The mixture was stirred at 0 ЊC for 1 h and then
a solution of the aldehyde 25 (1.34 g, 6.37 mmol) in THF (10
cm3) was added dropwise. The reaction was stirred at 0 ЊC for
6 h, quenched with saturated aqueous ammonium chloride (20
cm3) and extracted with diethyl ether (3 × 50 cm3). The com-
bined organic extracts were dried (MgSO4) and then evaporated
in vacuo. Chromatography of the residue on silica gel using
diethyl ether–light petroleum (bp 40–60 ЊC) (1:49 to 1:9) as
eluent gave both isomers of the triene.
(Z,E)-5,13-Bis(methoxycarbonyl)-9-methyltetradeca-5,9,13-
trienal 28
Dess–Martin periodinane oxidation of the alcohol 27 accord-
ing to the general procedure and using diethyl ether–light
petroleum (bp 40–60 ЊC) (1:3) as eluent gave the aldehyde (87%)
as a colourless oil; νmax(film)/cmϪ1 2955, 2712, 1716, 1629, 1436,
1381, 1194, 1174 and 1129; δH(360 MHz; CDCl3) 9.76 (1H, t,
J 1.6, CHO), 6.13 (1H, d, J 1.3, CHH᎐C), 5.87 (1H, t, J 7.3,
᎐
CH᎐C(CO CH )), 5.52 (1H, d, J 1.3, CHH᎐C), 5.13 (1 H, t,
᎐
᎐
2
3
J 7.1, CH᎐C(CH )), 3.75 (3H, s, OCH ), 3.74 (3H, s, OCH ),
᎐
3
3
3
2.53 (2H, app. q, J 7.3, CH CH᎐C(CO CH )), 2.42 (2H, dt,
᎐
2
2
3
The (Z,E)-isomer 26 eluted first (1.56 g, 54%) as a colourless
J 1.6 and 7.4, CH2CHO), 2.38–2.23 (4H, m), 2.16 (2H, app. q,
J 7.1, CH CH᎐C(CH )), 2.07 (2H, t, J 7.4, CH C(CO CH )᎐
oil; νmax(film)/cmϪ1 2950, 2929, 2857, 1721, 1631, 1460, 1437,
᎐
᎐
3
2
3
2
2
J. Chem. Soc., Perkin Trans. 1, 2000, 3522–3538
3531