brine, dried and concentrated. The crude product obtained was
purified by column chromatography on silica gel (80 g) with
hexane–ethyl acetate (60:1) to give ( )-1Z as a colorless liquid
(1.38 g, 85%); νmax(neat)/cmϪ1 3400, 3311, 2926, 2854, 2119,
1466, 1091, 1014, 970 and 723; δH 0.88 (3H, t, J 7.0), 1.27–1.45
(23H, m), 1.92–2.13 (6H, m), 2.56 (1H, d, J 2.1), 4.84 (1H, br s),
5.35 (2H, m), 5.61 (1H, dd, J 15.3, 6.2) and 5.92 (1H, dt, J 15.3,
6.2); δC 134.51, 129.88, 129.83, 128.33, 83.34, 73.89, 62.73,
31.91, 31.76, 29.73, 29.71, 29.52, 29.50, 29.43, 29.27, 29.16,
28.96, 28.80, 27.17, 22.63 and 14.08 (Found: C, 82.91; H, 11.95.
C22H38O requires C, 82.95; H, 12.03%).
1746, 1466, 1371, 1228, 1015, 968 and 723; δH 0.88 (3H, t, J 7.0),
1.25–1.43 (22H, m), 1.99–2.05 (6H, m), 2.10 (3H, s), 2.56 (1H,
d, J 2.1), 5.39 (2H, m), 5.53 (1H, dd, J 15.3, 6.1), 5.82 (1H, d,
J 6.1) and 6.02 (1H, dt, J 15.3, 6.8); δC 169.69, 137.23, 130.36,
130.31, 124.21, 79.86, 74.65, 64.07, 32.59, 31.98, 31.74, 29.63,
29.60, 29.51, 29.47, 29.13, 28.82, 28.60, 22.63, 21.06 and 14.09
(Found: C, 79.81; H, 11.28. C24H40O2 requires C, 79.94; H,
11.18%). The IR and NMR spectra of (Ϫ)-1E were identical
with those of ( )-1E.
Acetate (ϩ)-11E (0.3 g, 0.84 mmol) was hydrolysed with
Novozym 435 (0.12 g) in a mixture of acetone and 0.1 mol dmϪ3
phosphate buffer as described for (ϩ)-11Z (80% conversion).
Column chromatography gave (ϩ)-1E with >98 ee as a colorless
liquid (0.19 g, 72%); [α]D25 ϩ22.80 (c 1.21, MeOH); δC 134.58,
(3RS,4E,15E)-Docosa-4,15-dien-1-yn-3-ol [( )-1E]
This compound was prepared by treating 10E (1.5 g, 5.1 mmol)
with ethynylmagnesium chloride according to the procedure
described for ( )-1Z. Purification by column chromatography
as already described for ( )-1Z gave 1E as a colorless liquid
(1.38 g, 85%); νmax(neat)/cmϪ1 3400, 3311, 2924, 2854, 2117,
1466, 1092, 1016, 967 and 723; δH 0.88 (3H, t, J 7.0), 1.23–1.43
(23H, m), 1.95–2.10 (6H, m), 2.56 (1H, d, J 2.1), 4.84 (1H, br s),
5.39 (2H, m), 5.61 (1H, dd, J 15.3, 6.1) and 5.91 (1H, dt, J 15.3,
6.9); δC 134.55, 130.34, 130.29, 128.28, 83.30, 73.91, 62.73,
32.57, 31.91, 31.72, 29.60, 29.58, 29.51, 29.46, 29.42, 29.15,
29.11, 28.80, 22.62 and 14.08 (Found: C, 82.86; H, 12.08.
C22H38O requires C, 82.95; H, 12.03%).
1
130.35, 130.30 and 128.30. The IR and H NMR spectra were
identical with those of ( )-1E.
(R)-1-Ethylhex-5-enyl acetate [(R)-13]
A mixture of ( )-12 (5.0 g, 39 mmol), Novozym 435 (2.7 g),
vinyl acetate (10 g, 0.116 mol), and tert-butyl methyl ether (50
cm3) was stirred for 1.75 h at 30 ЊC (47% conversion). Purifi-
cation of the product by column chromatography on silica gel
(160 g) with hexane–diethyl ether (30:1) gave (R)-13 with 90%
ee as a colorless liquid (2.2 g, 44%); [α]D20 ϩ8.06 (c 2.70, pentane)
{lit.,7 [α]D20 Ϫ7.24 (c 3.01, pentane) for (S)-13}. The IR and
1H NMR spectra were identical with those of ( )-13 prepared
previously.7
(3S,4E,15Z)-Docosa-4,15-dien-1-yn-3-ol [(؉)-1Z]
A mixture of ( )-1Z (1.0 g, 3.1 mmol), Novozym 435 (0.4 g),
viny acetate (0.8 g, 9 mmol), and tert-butyl methyl ether (30
cm3) was stirred for 2 h at 30 ЊC (47% conversion). The reaction
mixture was filtered through Celite, and the filtrate was washed
with brine, dried and concentrated. Purification of the product
by column chromatography on silica gel (10 g) with hexane–
ethyl acetate (30:1) gave acetate (S)-(ϩ)-11Z with 95% ee as a
colorless liquid (0.5 g, 45%); [α]D25 ϩ17.96 (c 2.45, MeOH) and
alcohol (R)-(Ϫ)-1Z with 65% ee as a colorless liquid (0.49 g,
49%); [α]D25 Ϫ16.53 (c 2.85, MeOH). The enantiomeric ratio for
this biocatalytic acylation (E value), E = 85, was calculated
according to the method of Chen et al.11 Acetate (ϩ)-11Z:
νmax(neat)/cmϪ1 3312, 2926, 2855, 1746, 1466, 1371, 1229, 1015,
968 and 735; δH 0.88 (3H, t, J 7.0), 1.21–1.42 (22H, m), 2.01
(6H, m), 2.09 (3H, s), 2.56 (1H, d, J 2.1), 5.35 (2H, m), 5.54
(1H, dd, J 15.2, 6.2), 5.83 (1H, d, J 6.2) and 6.02 (1H, dt, J 15.2,
6.7); δC 169.64, 137.18, 129.87, 129.81, 124.20, 79.83, 74.64,
64.04, 31.96, 31.75, 29.72, 29.70, 29.49, 29.39, 29.26, 29.12,
28.95, 28.59, 27.18, 27.16, 22.63, 21.03 and 14.08 (Found:
C, 79.86; H, 11.29. C24H40O2 requires C, 79.94; H, 11.18%). The
IR and NMR spectra of (Ϫ)-1Z were identical with those of
( )-1Z.
(R)-1-Ethyl-4-formylbutyl acetate [(R)-14]
To a stirred solution of (R)-13 (1.7 g, 10 mmol) in dry THF (40
cm3) under nitrogen was added dropwise a solution of osmium
tetroxide (25 mg) in water (10 cm3) at room temperature. After
stirring for 2 h, finely powdered sodium periodate (6.4 g) was
added to the solution over one hour and the mixture was stirred
for 3 h. The mixture was extracted with diethyl ether, and the
ethereal solution was successively washed with saturated aq.
Na2SO3, saturated aq. NaHCO3 and brine, dried and concen-
trated. Purification of the residue by column chromatography
on silica gel (80 g) with hexane–diethyl ether (30:1) gave (R)-14
as a colorless liquid (1.0 g, 64%); νmax(neat)/cmϪ1 2969, 2881,
2725, 1733, 1460, 1375, 1296, 1021 and 957; δH 0.89 (3H, t,
J 7.5), 1.54–1.66 (6H, m), 2.06 (3H, s), 2.48 (2H, m), 4.82 (1H,
quintet, J 6.1) and 9.77 (1H, t, J 1.4); δC 202.03, 170.90, 74.74,
43.47, 32.82, 26.83, 21.12, 17.77 and 9.49.
(R,5EZ)-1-Ethylicos-5-enyl acetate [(R)-15]
Pentadecyltriphenylphosphonium bromide, which was freshly
prepared from triphenylphosphine (0.8 g, 3 mmol) and 1-
bromopentadecane (0.85 g, 3 mmol), was dissolved in 1,2-
dimethoxyethane (DME) (20 cm3). To the solution at Ϫ30 ЊC
was added 2.0 cm3 of 1.6 mol dmϪ3 BuLi in hexane and the
mixture was then allowed to warm gradually to room temper-
ature while being stirred, and was stirred for one hour. After the
resulting ylide solution had been cooled to Ϫ30 ЊC, a solution
of (R)-14 (0.44 g, 2.56 mmol) in dry DME (10 cm3) was added.
The reaction mixture was allowed to warm gradually to room
temperature with stirring; stirring was continued for 3 h. The
mixture was successively poured into saturated aq. NH4Cl and
extracted with diethyl ether. Usual work-up of the extract gave
a yellow liquid, which was purified by column chromatography
on silica gel (40 g) with hexane–ethyl acetate (40:1) to give (R)-
15 as a colorless liquid (0.39 g, 41%); νmax(neat)/cmϪ1 3006,
2925, 1741, 1461, 1373, 1243, 1090, 1019, 956 and 722; δH 0.88
(6H, t, J 7.2), 1.26–1.36 (26H, m), 1.55 (4H, m), 1.98–2.05 (7H,
including s at 2.04), 4.82 (1H, quintet, J 6.2) and 5.28–5.40 (2H,
m); δC 170.89, 130.46, 129.09, 75.32, 33.13, 31.90, 29.71, 29.67,
29.64, 29.55, 29.34, 29.30, 27.21, 26.95, 25.34, 22.66, 21.18,
14.08 and 9.53.
Acetate (ϩ)-11Z (0.3 g, 0.84 mmol) was added to a mixture
of Novozym 435 (0.12 g), acetone (3.6 cm3), and 0.1 mol dmϪ3
phosphate buffer (pH 7) (5.4 cm3). The mixture was stirred for
2.5 h at 30 ЊC, GLC analysis showed a conversion of 83%.
Column chromatography as already described for ( )-1Z gave
(ϩ)-1Z with >98% ee as a colorless liquid (0.2 g, 78%); [α]D25
ϩ24.43 (c 3.15, MeOH) {lit.,2 [α]D25 ϩ4.9 (c 4.5, MeOH); lit.,4 [α]D25
ϩ21.5 (c 1.1, MeOH)}; δC 134.59, 129.89, 129.84, 128.29, 27.19
1
and 27.17. The IR and H NMR spectra were identical with
those of ( )-1Z.
(3S,4E,15E)-Docosa-4,15-dien-1-yn-3-ol [(؉)-1E]
As described for ( )-1Z, ( )-1E (1.0 g, 3.1 mmol) was treated
with Novozym 435 (0.4 g) in the presence of vinyl acetate (0.8 g,
9 mmol); GLC analysis showed 45% conversion. Column
chromatography gave acetate (S)-(ϩ)-11E with 94% ee as a col-
orless liquid (0.46 g, 41%); [α]D25 ϩ16.17 (c 3.5, MeOH) and alco-
hol (R)-(Ϫ)-1E with 81% ee as a colorless liquid (0.51 g, 51%);
E = 76. Acetate (ϩ)-11E: νmax(neat)/cmϪ1 3312, 2926, 2854,
J. Chem. Soc., Perkin Trans. 1, 1999, 513–518
517