Synthesis of all the stereoisomers of 13,17-dimethyl-1-tritriacontene and 13,17-dimethyl-1-pentatriacontene, the contact sex pheromone components of the female tsetse fly, Glossina austeni

Article abstract of DOI:10.1002/1099-0690(200109)2001:17<3385::AID-EJOC3385>3.0.CO;2-P

All of the stereoisomers of 13,17-dimethyl-1-tritriacontene (1) and 13,17-dimethyl-1-pentatriacontene (2), the contact sex pheromone components of the female tsetse fly (Glossina austeni), were synthesized starting from the enantiomers of the protected syn- and anti-2,6-dimethylheptane-1,7-diol (3), which were prepared from the enantiomers of methyl 3-hydroxy-2-methylpropanoate (4) and methyl phenyl sulfone (5).

Full text of DOI:10.1002/1099-0690(200109)2001:17<3385::AID-EJOC3385>3.0.CO;2-P

FULL PAPER
Synthesis of All the Stereoisomers of 13,17-Dimethyl-1-tritriacontene and
13,17-Dimethyl-1-pentatriacontene, the Contact Sex Pheromone Components
of the Female Tsetse Fly, Glossina austeni[‡]
Taichi Kimura,[a] David A. Carlson,[b] and Kenji Mori*[a]
Keywords: Chirality / Hydrocarbons / Pheromones / Natural products
All of the stereoisomers of 13,17-dimethyl-1-tritriacontene (1)
and 13,17-dimethyl-1-pentatriacontene (2), the contact sex
pheromone components of the female tsetse fly (Glossina au-
steni), were synthesized starting from the enantiomers of the
protected syn- and anti-2,6-dimethylheptane-1,7-diol (3),
which were prepared from the enantiomers of methyl 3-hy-
droxy-2-methylpropanoate (4) and methyl phenyl sulfone (5).
Introduction
Tsetse flies are a hazard to the health of humans and
cattle in Africa because they spread the notorious sleeping
sickness. Therefore the elucidation of the pheromone com-
munication system among tsetse flies may help in modern
biocontrol efforts against this disease vector by ensuring
that the correct strain of fly is used in large-scale sterile
male release. The widespread, abundant and economically
important species Glossina austeni is the tsetse fly that is
under consideration for such control schemes.
Recently Carlson and co-workers isolated and identified
two alkenes as the components of the female-produced con-
tact sex pheromone in the cuticular wax of G. austeni.[1]
They are 13,17-dimethyl-1-tritriacontene (1, Scheme 1) and
13,17-dimethyl-1-pentatriacontene (2), both with two ste-
reogenic centers.
We became interested in synthesizing all the stereoiso-
mers of 1 and 2 for the purpose of establishing the absolute
configuration of the natural products. Scheme 1 shows the
retrosynthetic analysis of 1 and 2. It is evident that all the
stereoisomers of 1 and 2 can be derived from the three ste-
reoisomers of the building block 3. The anti-stereoisomers
(2R,6R)- and (2S,6S)-3 were recently prepared by us em-
ploying 4 and 5 as the starting materials, and used for the
synthesis of the pheromone components of the apple leaf-
miner.[2] The syn-stereoisomer (2R,6S)-3 is also a known
compound.[3,4]
Scheme 1. Structures and retrosynthetic analysis of the sex phero-
mone components 1 and 2 of the tsetse fly, Glossina austeni
ing block was previously prepared by the enzymatic desym-
metrization of syn-2,6-dimethylheptane-1,6-diol (A) with
isopropenyl acetate in the presence of lipase PS to give the
optically active half-acetate B.[3,4] This preparative route,
however, was rather lengthy and cumbersome due to the
difficulty in preparing A, and gave B in an overall yield of
23% with only about 95% de and 95% ee.[4] The unsatisfact-
ory de of A was due to the low diastereoselectivity in the
course of its preparation, while the imperfect enantiomeric
purity of B was caused by the incomplete enantioselectivity
of lipase PS to acetylate A. Considering the commercial
availability of almost pure enantiomers of methyl 3-hy-
droxy-2-methylpropanoate [(R)-4, ഠ100% ee; (S)-4, 99.8%
ee], we envisaged that the coupling strategy previously ad-
Results and Discussion
We first developed a new synthesis of (2R,6S)-3 as shown
in Scheme 2. This type of syn-1,5-dimethylated chiral build-
[‡]
Pheromone Synthesis, CCXI. Ϫ Part CCX: K. Fujita, K. Mori,
Biosci. Biotechnol. Biochem. 2001, 65, 1429Ϫ1433.
[a]
Department of Chemistry, Faculty of Science, Science
University of Tokyo,
Kagurazaka 1Ϫ3, Shinjuku-ku, Tokyo 162Ϫ8601, Japan
Fax: (internat.) ϩ81-3/3235-2214
[b]
U.S. Department of Agriculture, Agricultural Research Service,
Center for Medical, Agricultural and Veterinary Entomology,
P.O. Box 14565, Gainesville, Florida 32611, U.S.A.
Eur. J. Org. Chem. 2001, 3385Ϫ3390
WILEY-VCH Verlag GmbH, 69451 Weinheim, 2001
1434Ϫ193X/01/0917Ϫ3385 $ 17.50ϩ.50/0
3385

T. Kimura, D. A. Carlson, K. Mori
FULL PAPER
opted by us for the synthesis of (2R,6R)- and (2S,6S)-3[2] 12, whose tetrahydropyranyl (THP) group was removed to
would give better results than the known-enzymatic method give the alkenol (2S,6S)-13. This was tosylated to give the
of preparation[3] in both chemical and optical yields. The tosylate (2S,6S)-14. Further chain elongation of (2S,6S)-14
results summarized in Scheme 2 indeed confirmed our pre- with pentadecylmagnesium bromide under the Schlosser
mise.
conditions[9] yielded (13S,17R)-13,17-dimethyl-1-tritriacon-
tene (1). By employing heptadecylmagnesium bromide,
(13S,17R)-13,17-dimethyl-1-pentatriacontene (2) was also
synthesized. The overall yield of (13S,17R)-1 and that of
(13S,17R)-2 were both 12% based on (S)-4 (13 steps).
Scheme 2. Synthesis of the building block (2R,6R)-3: reagents: (a)
MeSO2Ph, nBuLi, THF/HMPA (78%); (b) nBuLi, (R)-6, THF/
HMPA (89%); (c) i) Na-Hg, EtOH; ii) MCPBA, CH2Cl2, SiO2
chromatog. (73%)
The starting (R)-4 was converted into the known iodide
(R)-6.[5] (S)-4 was then converted into another known iod-
ide (S)-7.[6] Alkylation of the anion derived from methyl
phenyl sulfone with (S)-7 furnished (R)-8.[7] The anion sub-
sequently derived from (R)-8 was alkylated with (R)-6 to
yield (2R,4RS,6S)-9. Finally the phenylsulfonyl group of 9
was removed by treatment with sodium amalgam to give
crude (2R,6S)-3 contaminated with a small amount (ca.
5%) of alkenes generated by β-elimination of the phenylsul-
fonyl group. The olefinic impurities were epoxidized with
m-chloroperbenzoic acid (MCPBA) to give a separable mix-
ture of (2R,6S)-3 and the epoxides. Purification of the mix-
ture by silica gel chromatography afforded pure (2R,6S)-3
Scheme 3. Synthesis of the stereoisomers of 1 and 2: reagents: (a)
(nBu)4NF, THF (quant.); (b) TsCl, C5H5N (quant.); (c) CH2ϭ
CH(CH2)9MgBr, Li2CuCl4, THF [60% for (2S,6S)-12; 67% for
(2R,6R)-17]; (d) p-TsOH, EtOH (93%); (e) Me(CH2)14MgBr, Li2C-
uCl4, THF [80% for (13S,17R)-1; 70% for (13R,17S)-1]; (f)
in 29% overall yield based on (R)-4 (7 steps). Reflecting Me(CH2)16MgBr, Li2CuCl4, THF [76% for (13S,17R)-2; 54% for
the high enantiomeric purity of (R)- and (S)-4, the product
(13R,17S)-2]; (g) Me2AlCl, CH2Cl2 (90%)
(2R,6S)-3 was of high stereochemical purity (Ͼ99% de and
Ͼ99% ee, see Exp. Sect.). It was therefore proved that the
For the synthesis of the (13R,17S)-isomers of 1 and 2,
classical iterative connection strategy to provide (2R,6S)-3 (2R,6S)-3 was converted into (2S,6R)-15 by treatment with
was better than the aesthetically appealing enzymatic de- dimethylaluminum chloride in dichloromethane[9] to re-
symmetrization strategy by virtue of the availability of the move only the THP group of 3. The corresponding tosylate
enantiomerically pure chiral building blocks (R)- and (S)-4. (2S,6R)-16 gave (2R,6R)-17 after chain elongation with 10-
Scheme 3 summarizes the conversion of (2R,6S)-3 to the undecenylmagnesium bromide. Deprotection of (2R,6R)-17
target alkenes 1 and 2. Removal of the tert-butyldimethylsi- gave the free alcohol (2R,6R)-13, whose tosylate (2R,6R)-
lyl (TBS) protective group of (2R,6S)-3 afforded the alcohol 14 was subjected to a second chain elongation to give
(2R,6S)-10, which was tosylated to give (2R,6S)-11. Chain- (13R,17S)-1 and (13R,17S)-2, respectively. The overall yield
elongation of 11 with 10-undecenylmagnesium bromide in of (13R,17S)-1 and that of (13R,17S)-2 were both 9% based
the presence of dilithium tetrachlorocuprate[8] gave (2S,6S)- on (S)-4 (13 steps). In the same manner, (2R,6R)-3[2] yielded
3386
Eur. J. Org. Chem. 2001, 3385Ϫ3390

Contact Sex Pheromone Components of the Female Tsetse Fly
FULL PAPER
1
(13S,17S)-1 and (13S,17S)-2, while (2S,6S)-3[2] furnished
(13R,17R)-1 and (13R,17R)-2. It should be added that the
syn-13,17-dimethylated 1 and 2 showed [α]D values (Ϯ0.05
and Ϯ0.17 in hexane) rather smaller than those (Ϯ0.27 and
Ϯ0.52 in hexane) of the anti-13,17-dimethylated 1 and 2.
These synthetic stereoisomers of 1 and 2 were sent to the
U.S.A. to compare them with the natural products. The
mass spectra of these synthetic hydrocarbons 1 and 2 show
near coincidence with the mass spectra of the natural
pheromone molecules. The two natural dimethylalkenes had
small amounts of inseparable isomers with their methyl
branches in different locations. This is suggested by the
mass spectra of the corresponding alkanes isolated at the
same time from Glossina austeni.[1] Such isomers would
contribute fragment ions missing from the mass spectra of
the very clean synthetic compounds 1 and 2. The scram-
bling of hydrogen ions in the mass spectra of both natural
and synthetic alkenes is also curious, an effect not really
conspicuous in unbranched alkenes.[1] An additional com-
plication is the comparison of high molecular weight mass
spectra recorded on different quadrupole instruments over
a period of 20 years, complicated by mass defects caused by
so many hydrogens, and the necessity to tune instruments
specifically for high mass ranges.
SiϪO), 1040 (s, CϪO). Ϫ H NMR (90 MHz, CDCl3): δ ϭ 0.00,
0.01 (each s, total 6 H, SiϪCH3), 0.85, 0.87 (each s, total 9 H, tBu),
0.62Ϫ1.10 (m, 6 H, 2-, 6-CH3), 1.10Ϫ2.20 (m, 12 H, 2-, 6-H, 3-, 5-
, 3ЈϪ5Ј-H2), 2.91Ϫ4.18 (m, 7 H, 4-H, 1-, 7-, 6Ј-H2), 4.51 (br. s, 1
H, 2Ј-H), 7.37Ϫ7.70 (m, 3 H, Ar-H), 7.70Ϫ7.97 (m, 2 H, Ar-H).
Ϫ C26H46O5SSi (498.7): calcd. C 62.61, H 9.31; found C 62.33,
H 9.24.
(2R,6S)-1-tert-Butyldimethylsilyloxy-2,6-dimethyl-7-tetrahydro-
pyranyloxyheptane [(2R,6S)-3]: Under argon atmosphere, a solution
of (2R,4RS,6S)-9 (2.2 g, 4.41 mmol) in dry ethanol (30 mL) was
added dropwise to 5% sodium amalgam (19.2 g, sodium 0.96 g,
42 mmol) at 0 °C. The mixture was stirred vigorously at room tem-
perature for 25 h. It was then filtered through Celite, and the filter
cake was washed several times with diethyl ether. The combined
filtrate and washings were concentrated in vacuo to give crude
(2R,6S)-3. This crude material contained ca. 5% of olefinic com-
pounds formed by elimination of the phenylsulfonyl group from
(2R,4RS,6S)-9. The crude (2R,6S)-3 was dissolved in CH2Cl2
(20 mL), and m-CPBA (0.38 g, 2.2 mmol) was added. The mixture
was stirred at room temperature for 18 h, then a sat. aqueous so-
dium thiosulfate and sat. aqueous NaHCO3 were added, and ex-
tracted with CH2Cl2. The combined organic phases were washed
with water and brine, dried with MgSO4, and concentrated in va-
cuo. The residue was chromatographed on silica gel (30 g, hexane/
ethyl acetate, 25:1) to remove the contaminating epoxide and give
1.16 g (73%) of (2R,6S)-3 as a colorless oil; n2D3 ϭ 1.4499. Ϫ [α]2D1
ϭ
ϩ2.21 (c ϭ 1.09, hexane). Ϫ IR (film): νmax ϭ 1255 cmϪ1 (s,
SiϪCH3), 1110 (s, SiϪO), 1035 (s, CϪO). Ϫ 1H NMR (90 MHz,
CDCl3): δ ϭ 0.03 (s, 6 H, SiϪCH3), 0.89 (s, 9 H, tBu), 0.48Ϫ1.14
(m, 6 H, 2-, 6-CH3), 1.14Ϫ2.02 (m, 14 H, 2-, 6-H, 3-, 5-, 3ЈϪ5Ј-
H2), 3.02Ϫ4.05 (m, 6 H, 1-, 7-, 6Ј-H2), 4.56 (br. s, 1 H, 2Ј-H).
Ϫ C20H42O3Si (358.6): calcd. C 66.98, H 11.81; found C 66.66,
H 11.62.
˜
In conclusion we synthesized each of the four stereoiso-
mers of 1 and 2. These stereoisomers are now being biot-
ested, and the result will hopefully establish the absolute
configuration of the pheromone components of Glossia aus-
teni. The syn-1,5-dimethylated building block (2R,6S)-3 will
serve as a versatile chiral building block in the synthesis of
syn-1,5-dimethylated aliphatic compounds.
(2R,6S)-2,6-Dimethyl-7-tetrahydropyranyloxy-1-heptanol [(2R,6S)-
10]: (nBu)4NF (1.0  solution in dry THF, 4.20 mL, 4.20 mmol) at
room temperature was added to a solution of (2R,6S)-3 (1.16 g,
3.23 mmol) in dry THF (10 mL). After stirring at room temper-
ature for 18 h, the mixture was poured into water and extracted
with diethyl ether. The combined organic phases were washed with
sat. aqueous NaHCO3 and brine, dried with MgSO4, and concen-
trated in vacuo. The residue was chromatographed on silica gel
(20 g, hexane/ethyl acetate, 5:1) to give 0.79 g (quant.) of (2R,6S)-
Experimental Section
General: IR: Jasco A-102. Ϫ 1H NMR: Jeol JNM-EX 90A
(90 MHz), Jeol JNM-LA400 (400 MHz) and Jeol JNM-LA500
(500 MHz) (TMS at δ ϭ 0.00 or CHCl3 at δ ϭ 7.26 as an internal
standard). Ϫ 13C NMR: Jeol JNM-LA500 (126 MHz) (CDCl3 at
δ ϭ 77.0 as an internal standard). Ϫ GC MS: Shimadzu QP5050A
with a DB-5 column (15 m ϫ 0.25 mm). Ϫ Optical rotation: Jasco
DIP-1000. Ϫ Column chromatography: Merck Kieselgel 60 Art
1.07734. Ϫ TLC: 0.25 mm Merck silica gel plates (60F-254).
10; n2D3 ϭ 1.4591. Ϫ [α]2D1 ϭ ϩ9.30 (c ϭ 1.32, hexane). Ϫ IR (film):
1
νmax ϭ 3400 cmϪ1 (s, OϪH), 1120 (s, CϪO), 1035 (s, CϪO). Ϫ H
˜
NMR (90 MHz, CDCl3): δ ϭ 0.91 (d, J ϭ 6.3 Hz, 6 H, 2-, 6-CH3),
1.03Ϫ1.93 (m, 15 H, 2-, 6-H, 3Ϫ5-, 3ЈϪ5Ј-H2, OH), 2.93Ϫ4.02 (m,
6 H, 1-, 7-, 6Ј-Hb), 4.56 (br. s, 1 H, 2Ј-H). Ϫ C14H28O3 (244.4):
calcd. C 68.81, H 11.55; found C 68.76, H 11.76.
(2R,4RS,6S)-1-tert-Butyldimethylsilyloxy-2,6-dimethyl-4-phenyl-
sulfonyl-7-tetrahydropyranyloxyheptane [(2R,4RS,6S)-9]: Under ar-
gon atmosphere, a solution of n-butyllithium in hexane (1.50 ,
12 mL, 18.0 mmol) at Ϫ78 °C was added dropwise to a stirred and
cooled solution of (R)-8 (5.07 g, 14.8 mmol) in dry THF (50 mL)
and dry HMPA (10 mL). After the addition, the mixture was kept
at Ϫ30 °C for 15 min. and then recooled to Ϫ78 °C. A solution
of (R)-6 (5.13 g, 18.1 mmol) in dry THF (50 mL) was then added
dropwise to the reaction mixture at Ϫ78 °C with stirring. The mix-
ture was stirred at ambient temperature for 28 h, then poured into
sat. aqueous NH4Cl and water at 0 °C, and extracted with diethyl
(2R,6R)-2,6-Dimethyl-7-tetrahydropyranyloxy-1-heptanol [(2R,6R)-
10]: In the same manner as described above, (2R,6R)-3 (0.99 g,
2.7 mmol) was converted into 0.63 g (95%) of (2R,6R)-10 (as a col-
orless oil); n2D3 ϭ 1.4609. Ϫ [α]2D3 ϭ ϩ2.26 (c ϭ 1.29, hexane). Its
IR and NMR spectra were almost identical with those of (2R,6S)-
10. Ϫ C14H28O3 (244.4): calcd. C 68.81, H 11.55; found C 68.96,
H 11.78.
(2S,6S)-2,6-Dimethyl-7-tetrahydropyranyloxy-1-heptanol [(2S,6S)-
ether. The combined organic phases were washed with water and 10]: In the same manner as described for the preparation of
brine, dried with MgSO4, and concentrated in vacuo. The residue (2R,6S)-10, (2S,6S)-3 (2.03 g, 5.66 mmol) was converted into 1.34 g
was chromatographed on silica gel (200 g, hexane/ethyl acetate, (97%) of (2S,6S)-10 (as a colorless oil); n2D4 ϭ 1.4590. Ϫ [α]2D2
ϭ
50:1) to give 6.66 g (89%) of (2R,4RS,6S)-9 as a yellow oil; n2D4
1.4961. Ϫ [α]2D1 ϭ ϩ3.91 (c ϭ 1.04, hexane). Ϫ IR (film): ν˜max
ϭ
Ϫ3.07 (c ϭ 1.17, hexane). Its IR and NMR spectra were identical
ϭ
with those of (2R,6R)-10. Ϫ C14H28O3 (244.4): calcd. C 68.81, H
11.55; found C 68.90, H 11.59.
1590 cmϪ1 (w, aromatic), 1310 (s, SO2), 1255 (s, SiϪCH3), 1090 (s,
Eur. J. Org. Chem. 2001, 3385Ϫ3390
3387

T. Kimura, D. A. Carlson, K. Mori
FULL PAPER
(2R,6S)-2,6-Dimethyl-7-tetrahydropyranyloxyheptyl p-Toluenesul-
[α]2D2 ϭ ϩ2.08 (c ϭ 1.06, hexane). Its IR and NMR spectra were
fonate [(2R,6S)-11]: p-Toluenesulfonyl chloride (670 mg, identical with those of (2R,6S)-12. Ϫ C25H48O2 (380.6): calcd. C
3.51 mmol) was added to a solution of (2R,6S)-10 (665 mg, 78.88, H 12.71; found C 78.72, H 12.48.
2.72 mmol) in dry pyridine (7 mL) at 0 °C. After stirring at 4 °C
(2S,6S)-2,6-Dimethyl-17-octadecen-1-ol [(2S,6S)-13]: p-Toluenesul-
fonic acid monohydrate (10.0 mg, 0.06 mmol) was added to a solu-
tion of (2S,6S)-12 (519 mg, 1.36 mmol) in 95% EtOH (5 mL) and
the mixture was warmed up to 50 °C. The mixture was stirred for
5 h at 50 °C and then cooled to room temperature. After neutraliza-
tion with K2CO3, the mixture was extracted with diethyl ether. The
combined organic phases were washed with sat. aqueous NaHCO3
and brine, dried with MgSO4 and concentrated in vacuo. The res-
idue was chromatographed on silica gel (10 g, hexane/ethyl acetate,
for 12 h, the mixture was poured into water at 0 °C and extracted
with diethyl ether. The combined organic phases were washed with
sat. aqueous CuSO4, sat. aqueous NaHCO3 and brine, dried with
MgSO4, and concentrated in vacuo to give 1.10 g (quant.) of crude
(2R,6S)-11. This was employed in the next step without further
purification. Ϫ IR (film): ν˜max ϭ 1360 cmϪ1 (s, SO2), 1180 (s, SO2),
1120 (m, SO2), 1030 (s, CϪO). Ϫ 1H NMR (300 MHz, CDCl3):
δ ϭ 0.88 (d, J ϭ 6.9 Hz, 6 H, 2-, 6-CH3), 0.97Ϫ1.90 (m, 14 H, 2-,
6-H, 3Ϫ5-, 3ЈϪ5Ј-H2), 2.45 (s, 3 H, Ar-CH3), 3.07Ϫ4.16 (m, 6 H,
1-, 7-, 6Ј-Ha), 4.53 (br, 1 H, 2Ј-H), 7.34 (d, J ϭ 8.1 Hz, 2 H, Ar-
H), 7.80 (d, J ϭ 8.1 Hz, 2 H, Ar-H).
30:1) to give 377 mg (93%) of (2S,6S)-13 as a colorless oil; n2D6
1.4529. Ϫ [α]2D6 ϭ Ϫ6.56 (c ϭ 1.01, hexane). Ϫ IR (film): ν˜max
ϭ
ϭ
3330 cmϪ1 (s, OϪH), 1640 (m, CϭC). Ϫ 1H NMR (300 MHz,
CDCl3): δ ϭ 0.84 (d, J ϭ 6.3 Hz, 3 H, 6-CH3), 0.92 (d, J ϭ 6.9 Hz,
3 H, 2-CH3), 0.98Ϫ1.69 (m, 27 H, 2-, 6-H, 3-, 5-, 7-, 15-H2, OH),
2.04 (q, J ϭ 6.6 Hz, 2 H, 16-H2), 3.37Ϫ3.57 (m, 2 H, 1-Ha),
4.86Ϫ5.03 (m, 2 H, 18-Ha), 5.74Ϫ5.90 (m, 1 H, 17-H). Ϫ C20H40O
(296.5): calcd. C 81.01, H 13.59; found C 81.21, H 13.78.
(2R,6R)-2,6-Dimethyl-7-tetrahydropyranyloxyheptyl p-Toluenesul-
fonate [(2R,6R)-11]: In the same manner as described above,
(2R,6R)-10 (238 mg, 1.15 mmol) was converted into 387 mg (qu-
ant.) of (2R,6R)-11. This was employed in the next step without
further purification. Its IR and NMR spectra were almost identical
with those of (2R,6S)-11.
(2R,6S)-2,6-Dimethyl-17-octadecen-1-ol [(2R,6S)-13]: In the same
manner as described above, (2R,6S)-12 (318 mg, 0.835 mmol) was
converted into 165 mg (88%) of (2R,6S)-13 (as a colorless oil);
n2D4 ϭ 1.4496. Ϫ [α]2D6 ϭ ϩ6.35(c ϭ 0.95, hexane). Its IR and NMR
spectra were almost identical with those of (2S,6S)-13. Ϫ C25H48O2
(296.5): calcd. C 81.01, H 13.59; found C 80.93, H 13.70.
(2S,6S)-2,6-Dimethyl-7-tetrahydropyranyloxyheptyl p-Toluenesul-
fonate [(2S,6S)-11]: In the same manner as described for the pre-
paration of (2R,6S)-11, (2S,6S)-10 (1.23 g, 5.03 mmol) was con-
verted into 1.95 g (98%) of (2S,6S)-11. This was employed in the
next step without further purification. Its IR and NMR spectra
were identical with those of (2R,6R)-11.
(2S,6R)-2,6-Dimethyl-17-octadecene-1-ol [(2S,6R)-13]: In the same
manner as described for the preparation of (2S,6S)-13, (2S,6R)-12
(1.08 g, 28.4 mmol) was converted into 0.71 g (84%) of (2S,6R)-12
(as a colorless oil); n2D2 ϭ 1.4600. Ϫ [α]2D8 ϭ Ϫ6.62 (c ϭ 1.05, hex-
ane). Its IR and NMR spectra were identical with those of (2R,6S)-
13. Ϫ C25H48O2 (296.5): calcd. C 81.01, H 13.59; found C 80.81,
H 13.87.
(2S,6S)-2,6-Dimethyl-1-tetrahydropyranyloxy-17-octadecene
[(2S,6S)-12]: Magnesium (410 mg, 16.9 mmol) was added to an ar-
gon-purged flask. A solution of 11-bromo-1-undecene (2.62 g,
11.2 mmol) in dry THF (25 mL) was added dropwise to the metal
and the mixture was stirred at room temperature for 1 h. The re-
sulting solution was used immediately. Under argon atmosphere,
the above Grignard reagent and a solution of Li2CuCl4 in dry THF
(0.32 , 0.85 mL, 0.27 mmol) at Ϫ78 °C were added to a solution
of (2R,6S)-11 (1.10 g, 2.72 mmol) in dry THF (10 mL). The mix-
ture was allowed to warm up to 4 °C, and stirred at 4 °C for 12 h.
The mixture was quenched with sat. aqueous NH4Cl and water,
and extracted with diethyl ether. The combined organic phases
were washed with brine, dried with MgSO4, and concentrated in
vacuo. The residue was chromatographed on silica gel (40 g, hex-
ane/ethyl acetate, 75:1) to give 619 mg (60%) of (2S,6S)-12 as a
colorless oil; n2D9 ϭ 1.4554. Ϫ [α]2D6 ϭ ϩ1.75 (c ϭ 1.10, hexane). Ϫ
(2S,6S)-2,6-Dimethyl-17-octadecenyl p-Toluenesulfonate [(2S,6S)-
14]: p-Toluenesulfonyl chloride (264 mg, 1.38 mmol) was added to
a solution of (2S,6S)-13 (316 mg, 1.06 mmol) in dry pyridine
(3 mL) at 0 °C. After stirring at 4 °C for 15 h, the mixture was
poured into water at 0 °C and extracted with diethyl ether. The
combined organic phases were washed with sat. aqueous CuSO4,
sat. aqueous NaHCO3 and brine, dried with MgSO4, and concen-
trated in vacuo to give 463 mg (97%) of crude (2S,6S)-14. This was
employed in the next step without further purification. Ϫ IR (film):
IR (film): νmax ϭ 1640 cmϪ1(m, CϭC), 1120 (s, CϪO), 1035 (s,
˜
νmax ϭ 1640 cmϪ1 (m, CϭC), 1600 (m, aromatic), 1365 (s, SO2),
˜
1
CϪO). Ϫ H NMR (300 MHz, CDCl3): δ ϭ 0.84 (d, J ϭ 6.3 Hz,
1
1180 (s, SO2). Ϫ H NMR (90 MHz, CDCl3): δ ϭ 0.64Ϫ0.94 (m,
3 H, 6-CH3), 0.98Ϫ1.90 (m, 35 H, 2-CH3, 6-H, 3Ϫ5-, 7Ϫ15-, 3Ϫ5Ј-
H2, 2-, 6-H), 2.04 (q, J ϭ 6.6 Hz, 2 H, 16-H2), 3.04Ϫ3.92 (m, 4 H,
1-, 6Ј-H2), 4.50Ϫ4.52 (m, 1 H, 2Ј-H), 4.88Ϫ5.04 (m, 2 H, 18-H2),
5.73Ϫ5.90 (m, 1 H, 17-H). Ϫ C25H48O2 (380.6): calcd. C 78.88, H
12.71; found C 79.11, H 12.80.
2-, 6-CH3), 0.94Ϫ2.13 (m, 28 H, 2-, 6-H, 3Ϫ5-, 7Ϫ16-H2), 2.45 (s,
3 H, Ar-CH3), 3.84 (dd, J ϭ 3.0, 5.7 Hz, 2 H, 1-Ha), 4.82Ϫ5.10
(m, 2 H, 18-H2), 5.55Ϫ6.01 (m, 1 H, 17-H), 7.34 (d, J ϭ 8.2 Hz, 2
H, Ar-H), 7.78 (d, J ϭ 8.2 Hz, 2 H, Ar-H).
(2R,6S)-2,6-Dimethyl-17-octadecenyl p-Toluenesufonate [(2R,6S)-
14]: In the same manner as described above, (2R,6S)-13 (165 mg,
0.55 mmol) was converted into 231 mg (95%) of (2R,6S)-14. This
was employed in the next step without further purification. Its IR
and NMR spectra were almost identical with those of (2S,6S)-14.
(2R,6S)-2,6-Dimethyl-1-tetrahydropyranyloxy-17-octadecene
[(2R,6S)-12]: In the same manner as described above, (2R,6R)-11
(396 mg, 0.993 mmol) was converted into 321 mg (85%) of (2R,6S)-
12 (as a colorless oil); n2D3 ϭ 1.4601. Ϫ [α]2D2 ϭ Ϫ 3.64 (c ϭ 1.01,
hexane). Its IR and NMR spectra were almost identical with those
of (2S,6S)-12. Ϫ C25H48O2 (380.6): calcd. C 78.88, H 12.71; found
C 78.77, H 13.04.
(2S,6R)-2,6-Dimethyl-17-octadecenyl p-Toluenesufonate [(2S,6R)-
14]: In the same manner as described for the preparation of
(2S,6R)-2,6-Dimethyl-1-tetrahydropyranyloxy-17-octadecene (2S,6S)-14, (2S,6R)-13 (192 mg,0.64 mmol) was converted into
[(2S,6R)-12]: In the same manner as described for the preparation 289 mg (quant.) of (2S,6R)-14. This was employed in the next step
of (2S,6S)-12, (2S,6S)-11 (1.95 g, 4.89 mmol) was converted into
without further purification. Its IR and NMR spectra were ident-
ical with those of (2R,6S)-14.
1.19 g (62%) of (2S,6R)-12 (as a colorless oil); n2D0 ϭ 1.4602. Ϫ
3388
Eur. J. Org. Chem. 2001, 3385Ϫ3390

Contact Sex Pheromone Components of the Female Tsetse Fly
FULL PAPER
(13S,17R)-13,17-Dimethyl-1-tritriacontene [(13S,17R)-1]: Magnes-
phases were washed with brine, dried with MgSO4, and concen-
ium (83 mg, 3.41 mmol) was added to an argon-purged flask. A trated in vacuo. The residue was chromatographed on silica gel
solution of 1-bromopentadecane(710 mg, 2.44 mmol) in dry THF
(7 mL) was added dropwise to the metal, and the mixture was
stirred at room temperature for 1 h. The resulting solution was used
immediately. Under argon atmosphere, the above Grignard reagent
(20 g, hexane) and silver nitrate-impregnated silica gel (20%, 25 g)
to give 207 mg (76%) of (13S,17R)-2 as a colorless oil; n2D8 ϭ 1.4591.
Ϫ [α]2D8 ϭ ϩ0.055 (c ϭ 1.90, hexane). Ϫ IR (film): νmax ϭ 3100
˜
cmϪ1 (w, CϭCϪH), 2940 (s, CϪH), 2860 (s, CϪH), 1640 (m, Cϭ
and a solution of Li2CuCl4 in dry THF (0.32 , 0.20 mL, C), 1460 (s, CϪH), 1380 (m, CϪH), 990 (w), 910 (m), 720 (w). Ϫ
0.10 mmol) were added to a solution of (2S,6S)-14 (246 mg, 1H NMR (500 MHz, CDCl3): δ ϭ 0.84 (d, J ϭ 8.2 Hz, 6 H, 13-,
0.56 mmol) in dry THF (3 mL) at Ϫ78 °C. The mixture was al-
lowed to warm to 4 °C, and stirred at this temperature for 24 h.
17-CH3), 0.88 (t, J ϭ 8.8 Hz, 3 H, 35-H3), 1.00Ϫ1.45 (m, 60 H, 13-
, 17-H, 4Ϫ12-, 14Ϫ16-, 18Ϫ34-H2), 2.04 (q, J ϭ 9.4 Hz, 2 H, 3-
The mixture was quenched with sat. aqueous NH4Cl and water, H2), 4.87Ϫ5.05 (m, 2 H, 1-H2), 5.72Ϫ5.87 (m, 1 H, 2-H). Ϫ 13C
and extracted with distilled hexane. The combined organic phases
were washed with brine, dried with MgSO4, and concentrated in
NMR (125 MHz, CDCl3): δ ϭ 14.1, 19.8, 22.7, 24.5, 27.1, 29.0,
29.2, 29.4, 29.5, 29.6, 29.74, 29.77, 30.1, 32.0, 32.8, 33.8, 37.1, 37.5,
vacuo. The residue was chromatographed on silica gel (20 g, hex- 114.1, 139.2. Ϫ EI MS (70 eV): m/z (%) ϭ 519 (0.6) [Mϩ ϩ1], 365
ane) and silver nitrate-impregnated silica gel (20%, 25 g) to give (0.4), 349 (0.5), 321 (0.6), 308 (0.6), 278 (8.1), 210 (9.0), 195 (20.4),
222 mg (80%) of (13S,17R)-1 as a colorless oil; n2D4 ϭ 1.4580. Ϫ
139 (22.0), 125 (45.6), 111 (100.0). Ϫ C37H74 (519.0): calcd. C
85.63, H 14.37; found C 85.69, H 14.39. Ϫ GC [column: DB-5
[α]2D5 ϭ ϩ0.17 (c ϭ 1.40, CHCl3). Ϫ IR (film): νmax ϭ 3080 cmϪ1
˜
(w, CϭCϪH), 2930 (s, CϪH), 2850 (s, CϪH), 1640 (m, CϭC), (0.25 mm ϫ 30 m), 200 to 320 °C/min., ϩ4.0 °C/min.; carrier gas:
1460 (s, CϪH), 1380 (m, CϪH), 990 (w), 910 (s), 720 (w). Ϫ 1H He, pressure: 100 kPa]: tR ϭ 36.7 min. (98.5% chemical purity).
NMR (500 MHz, CDCl3): δ ϭ 0.84 (d, J ϭ 8.0 Hz, 6 H, 13-, 17-
(13S,17S)-13,17-Dimethyl-1-pentatriacontene [(13S,17S)-2]: In the
CH3), 0.88 (t, J ϭ 8.5 Hz, 3 H, 33-H3), 0.99Ϫ1.45 (m, 56 H, 13-,
same manner as described above, (2R,6S)-14 (97 mg, 0.22 mmol)
17-H, 4Ϫ12-, 14Ϫ16-, 18Ϫ32-H2), 2.04 (q, J ϭ 9.5 Hz, 2 H, 3-H2),
was converted into 72 mg (65%) of (13S,17S)-2 (as a colorless oil);
n2D4 ϭ 1.4496. Ϫ [α]2D6 ϭ ϩ0.52 (c ϭ 3.01, hexane). Its IR, NMR
and MS spectra were almost identical with those of (13S,17R)-2.
Ϫ C37H74 (519.0): calcd. C 85.63, H 14.37; found C 85.81, H 14.56.
Ϫ GC [column: DB-5 (0.25 mm ϫ 30 m), 200 to 320 °C/min.,
ϩ4.0 °C/min.; carrier gas: He, pressure: 100 kPa]: tR ϭ 36.4 min.
(96.5% chemical purity).
4.86Ϫ5.05 (m, 2 H, 1-H2), 5.73Ϫ5.87 (m,1 H, 2-H). Ϫ 13C NMR
(125 MHz, CDCl3): δ ϭ 14.1, 19.8, 22.7, 24.5, 27.1, 29.0, 29.2, 29.4,
29.6, 29.70, 29.72, 29.75, 29.79, 30.1, 32.0, 32.8, 33.9, 37.1, 37.2,
37.5, 114.1, 139.2. Ϫ EI MS (70 eV): m/z (%) ϭ 491 (1.6) [Mϩ ϩ1],
336 (0.8), 321(0.9), 280 (2.4), 266 (6.2), 251 (9.5), 250 (10.4), 210
(12.1), 192 (20.8), 182 (9.0), 167 (9.9), 153 (13.0), 139 (22.3), 125
(45.4), 111 (100.0). Ϫ C35H70 (490.9): calcd. C 85.63, H 14.37;
found C 85.88, H 14.63. Ϫ GC [column: DB-5 (0.25 mm ϫ 30
m), 200 to 320 °C/min., ϩ4.0 °C/min.; carrier gas: He, pressure:
100 kPa]: tR ϭ 32.4 min. (97.8% chemical purity).
(13R,17R)-13,17-Dimethyl-1-pentatriacontene [(13R,17R)-2]: In the
same manner as described for the preparation of (13S,17R)-2,
(2S,6R)-14 (271 mg, 0.623 mmol) was converted into 234 mg (70%)
of (13R,17R)-2 (as a colorless oil); n2D4 ϭ 1.4600. Ϫ [α]2D3 ϭ Ϫ0.27
(c ϭ 2.84, hexane). Its IR, NMR and MS spectra were identical
with those of (13S,17S)-2. Ϫ C37H74 (519.0): calcd. C 85.63, H
14.37; found C 85.35, H 14.55. Ϫ GC [column: DB-5 (0.25 mm
ϫ 30 m), 200 to 320 °C/min., ϩ4.0 °C/min.; carrier gas: He, pres-
sure: 100 kPa]: tR ϭ 36.5 min. (98.2% chemical purity).
(13S,17S)-13,17-Dimethyl-1-tritriacontene [(13S,17S)-1]: In the
same manner as described above, (2R,6S)-14 (220 mg, 0.506 mmol)
was converted into 127 mg (45%) of (13S,17S)-1 (as a colorless oil);
n2D2 ϭ 1.4574. [α]2D2 ϭ ϩ0.49 (c ϭ 2.20, hexane). Its IR, NMR and
MS spectra were almost identical with those of (13S,17R)-1. Ϫ
C35H70 (490.9): calcd. C 85.63, H 14.37; found C 85.53, H 14.66.
Ϫ GC [column: DB-5 (0.25 mm ϫ 30 m), 200 to 320 °C/min., ϩ4.0
°C/min.; carrier gas: He, pressure: 100 kPa]: tR ϭ 32.9 min. (98.0%
chemical purity).
(2S,6R)-7-tert-Butyldimethylsilyloxy-2,6-dimethyl-1-heptanol
[(2S,6R)-15]: Under argon atmosphere, a solution of dimethylalum-
inum chloride in hexane (1.01 , 8.3 mL, 8.38 mmol) was added
dropwise to a stirred and cooled solution of (2R,6S)-3 (1.50 g,
4.18 mmol) in dry CH2Cl2 (15 mL) at Ϫ30 °C. After the addition,
the mixture was stirred at ambient temperature for 44 h, then
poured into sat. aqueous NaHCO3 and extracted with diethyl ether.
The combined organic phases were washed with sat. aqueous
NaHCO3 and brine, dried with MgSO4, and concentrated in vacuo.
The residue was chromatographed on silica gel (30 g, hexane/ethyl
acetate, 30:1) to give 1.03 g (90%) of (2S,6R)-15 as a colorless oil;
n2D2 ϭ 1.4449. Ϫ [α]2D7 ϭ Ϫ3.49 (c ϭ 1.10, CHCl3). Ϫ IR (film):
(13R,17R)-13,17-Dimethyl-1-tritriacontene [(13R,17R)-1]: In the
same manner as described above for the preparation of (13S,17R)-
1, (2S,6R)-14 (275 mg, 0.633 mmol) was converted into 218 mg
(70%) of (13R,17R)-1 (as a colorless oil); n2D4 ϭ 1.4563. Ϫ [α]2D4
ϭ
Ϫ0.40 (c ϭ 3.35, hexane). Its IR, NMR and MS spectra were ident-
ical with those of (13S,17S)-1. Ϫ C35H70 (490.9): calcd. C 85.63, H
14.37; found C 85.38, H 14.60. Ϫ GC [column: DB-5 (0.25 mm
ϫ 30 m), 200 to 320 °C/min., ϩ4.0 °C/min.; carrier gas: He, pres-
sure: 100 kPa]: tR ϭ 32.9 min. (97.9% chemical purity).
νmax ϭ 3340 cmϪ1 (s, OϪH), 1250 (s, SiϪCH3), 1095 (s, SiϪO). Ϫ
˜
(13S,17R)-13,17-Dimethyl-1-pentatriacontene [(13S,17R)-2]: Mag-
nesium (82 mg, 3.4 mmol) was added to an argon-purged flask. A
solution of 1-bromoheptadecane (670 mg, 2.10 mmol) in dry THF
(7 mL) was added dropwise to the metal, and the mixture was
stirred at room temperature for 1 h. The resulting solution was used
immediately. Under argon atmosphere, the above Grignard reagent
1H NMR (90 MHz, CDCl3): δ ϭ 0.03 (s, 6 H, SiϪCH3), 0.89 (s, 9
H, tBu), 0.58Ϫ1.82 (m, 15 H, 2-, 6-H, 3-, 5-H2, 2-, 6-CH3, OH),
3.10Ϫ3.67 (m, 4 H, 1-, 7-H2). Ϫ C15H34O2Si (274.2): calcd. C 65.63,
H 12.48; found C 65.47, H 12.71.
(2S,6R)-2,6-Dimethyl-7-(tert-butyldimethylsilyloxyheptyl) p-Tolu-
and a solution of Li2CuCl4 in dry THF (0.32 , 0.16 mL, enesulfonate [(2S,6R)-16]: p-Toluenesulfonyl chloride (0.82 g,
0.051 mmol) were added to a solution of (2S,6S)-14 (230 mg, 4.3 mmol) was added to a solution of (2S,6R)-15 (0.91 g, 3.3 mmol)
0.53 mmol) in dry THF (3 mL) at Ϫ78 °C. The mixture was al-
lowed to warm to 4 °C, and stirred at this temperature for 36 h.
in dry pyridine (10 mL) at 0 °C. After stirring at 4 °C for 24 h, the
mixture was poured into water at 0 °C and extracted with diethyl
The mixture was quenched with sat. aqueous NH4Cl and water, ether. The combined organic phases were washed with sat. aqueous
and then extracted with distilled hexane. The combined organic
CuSO4, sat. aqueous NaHCO3 and brine, dried with MgSO4, and
3389
Eur. J. Org. Chem. 2001, 3385Ϫ3390

T. Kimura, D. A. Carlson, K. Mori
FULL PAPER
concentrated in vacuo to give 1.33 g (98%) of crude (2S,6R)-16.
This was employed in the next step without further purification. Ϫ
(2R,6R)-2,6-Dimethyl-17-octadecenyl p-Toluenesufonate [(2R,6R)-
14]: In the same manner as described above, (2R,6R)-13 (165 mg,
0.55 mmol) was converted into 231 mg (95%) of (2R,6R)-14. This
IR (film): νmax ϭ 1600 cmϪ1 (w, aromatic), 1365 (s, SO2), 1250 (s,
˜
SiϪCH3), 1175 (s, SO2), 1100 (s, SiϪO), 1020 (w, CϪO). Ϫ 1H was employed in the next step without further purification. Its IR
NMR (90 MHz, CDCl3): δ ϭ 0.03 (s, 6 H, Si-CH3), 0.89 (s, 9 H, and NMR spectra were identical with those of (2S,6S)-14.
tBu) 0.58Ϫ2.00 (m, 14 H, 2-, 6-H, 3Ϫ5-H2, 2-,6-CH3), 2.45 (s, 3
(13R,17S)-13,17-Dimethyl-1-tritriacontene [(13R,17S)-1]: In the
H, Ar-CH3), 3.37 (dd, J ϭ 1.8, 4.5 Hz, 2 H, 7-H2), 3.85 (dd, J ϭ
same manner as described for the preparation of (13S,17R)-1,
2.7, 4.5 Hz, 2 H, 1-H2), 7.34 (d, J ϭ 8.1 Hz, 2 H, Ar-H), 7.78 (d,
(2R,6R)-14 (275 mg, 0.633 mmol) was converted into 218 mg (70%)
J ϭ 8.1 Hz, 2 H, Ar-H).
of (13R,17S)-1 (as a colorless oil); n2D4 ϭ 1.4572. Ϫ [α]2D4 ϭ Ϫ 0.08
(2R,6R)-2,6-Dimethyl-1-tert-butyldimethylsilyloxy-17-octadecene
[(2R,6R)-17]: Magnesium (0.48 g, 20 mmol) was added to an argon-
(c ϭ 1.29, hexane). Its IR, NMR and MS spectra were identical
with those of (13S,17R)-1. Ϫ C35H70 (490.9): calcd. C 85.63, H
14.37; found C 85.83, H 14.43. Ϫ GC [column: DB-5 (0.25 mm
ϫ 30 m), 200 to 320 °C/min., ϩ4.0 °C/min.; carrier gas: He, pres-
sure: 100 kPa]: tR ϭ 32.5 min. (97.7% chemical purity).
purged flask.
A solution of 11-bromo-1-undecene (3.09 g,
13.3 mmol) in dry THF (30 mL) was added dropwise to the metal,
and the mixture was stirred at room temperature for 1 h. The re-
sulting solution was used immediately. Under argon atmosphere,
the above Grignard reagent and a solution of Li2CuCl4 in dry THF
(0.32 , 1.0 mL, 0.27 mmol) were added to a solution of (2S,6R)-
16 (1.33 g, 3.22 mmol) in dry THF (13 mL) at Ϫ78 °C. The mixture
was allowed to warm up to 4 °C, and stirred at this temperature
for 33 h. The mixture was quenched with sat. aqueous NH4Cl and
water, and extracted with diethyl ether. The combined organic
phases were washed with brine, dried with MgSO4, and concen-
trated in vacuo. The residue was chromatographed on silica gel
(50 g, hexane/ethyl acetate, 100:1) to give 0.89 g (67%) of (2R,6R)-
17 as a colorless oil; n2D8 ϭ 1.4468. Ϫ [α]2D6 ϭ ϩ1.36 (c ϭ 1.25,
hexane). Ϫ IR (film): ν˜max ϭ 1640 cmϪ1 (m, CϭC), 1255 (s,
SiϪCH3), 1095 (s, SiϪO). Ϫ 1H NMR (300 MHz, CDCl3): δ ϭ
0.04 (s, 6 H, Si-CH3), 0.89 (s, 9 H, tBu) 0.80Ϫ0.97 (m, 6 H, 2-,6-
CH3), 0.97Ϫ1.63 (m, 26 H, 3Ϫ5-, 7Ϫ15-, 2-, 6-H), 2.04 (q, J ϭ
6.6 Hz, 2 H, 16-H2), 3.34 (dd, J ϭ 6.6, 9.9 Hz, 1 H 1-Ha), 3.44 (dd,
J ϭ 5.7, 9.9 Hz, 1 H 1-Hb), 4.89Ϫ5.03 (m, 2 H, 18-H2), 5.74Ϫ5.88
(m, 1 H, 17-H). Ϫ C26H54OSi (410.8): calcd. C 76.34, H 13.29;
found C 76.10, H 13.21.
(13R,17S)-13,17-Dimethyl-1-pentatriacontene [(13R,17S)-2]: In the
same manner as described for the preparation of (13S,17R)-2,
(2R,6R)-14 (199 mg, 0.458 mmol) was converted into 129 mg (54%)
of (13R,17S)-2 (as a colorless oil); n2D2 ϭ 1.4600. Ϫ [α]2D6 ϭ Ϫ0.07
(c ϭ 1.30, hexane). Its IR, NMR and MS spectra were identical
with those of (13S,17R)-2. Ϫ C37H74 (519.0): calcd. C 85.63, H
14.37; found C 85.41, H 14.64. Ϫ GC [column: DB-5 (0.25 mm
ϫ 30 m), 200 to 320 °C/min., ϩ4.0 °C/min.; carrier gas: He, pres-
sure: 100 kPa]: tR ϭ 36.8 min. (96.9% chemical purity).
Acknowledgments
We thank Dr. E. D. De Vilbiss (U. S. Department of Agriculture,
Plant Science Institute, Beltsville, Maryland) for MS measure-
ments. We are grateful to Miss Kaoru Marukawa for her help in
preparing the manuscript. Our thanks are due to Dr. K. Sakashita
(Mitsubishi Rayon Co., Tokyo) for the gift of (R)- and (S)-4. We
also thank Dr. H. Takikawa and Mr. Y. Nakamura for discussion.
(2R,6R)-2,6-Dimethyl-17-octadecen-1-ol
[(2R,6R)-13]:
p-Tolu-
enesulfonic acid monohydrate (15.0 mg, 0.09 mmol) was added to
a solution of (2R,6R)-17 (738 mg, 1.80 mmol) in 95% EtOH (4 mL)
and THF (4 mL) and the mixture was warmed up to 50 °C. The
mixture was stirred for 5 h at 70 °C, and cooled to room temper-
ature. After neutralization with K2CO3, the mixture was extracted
with diethyl ether. The combined organic phases were washed with
sat. aqueous NaHCO3 and brine, dried with MgSO4 and concen-
trated in vacuo. The residue was chromatographed on silica gel
(20 g, hexane/ethyl acetate, 30:1) to give 455 mg (86%) of (2R,6R)-
13 as a colorless oil; n2D4 ϭ 1.4595. Ϫ [α]2D7 ϭ ϩ6.40 (c ϭ 1.05,
hexane). Ϫ IR (film): ν˜max ϭ 3350 cmϪ1 (s, OϪH), 1640 (m, Cϭ
[1]
D. A. Carlson, B. D. Sutton, U. R. Bernier, Insect. Sci. Applic.
in press.
[2]
Y. Nakamura, K. Mori, Eur. J. Org. Chem. 2000, 2745Ϫ2753.
[3]
ˆ
R. Chenevert, M. Desjardins, J. Org. Chem. 1996, 61,
1219Ϫ1222.
[4]
[5]
[6]
Y. Nakamura, K. Mori, Eur. J. Org. Chem. 1999, 2175Ϫ2182.
K. Mori, Tetrahedron 1983, 39, 3107Ϫ3109.
E. J. Thomas, J. W. F. Whitehead, J. Chem. Soc., Perkin Trans.
1 1989, 507Ϫ518.
J. Mulzer, A. Mantoulidis, E. Öhler, Tetrahedron Lett. 1998,
39, 8633Ϫ8636.
C. Fouquet, M. Schlosser, Angew. Chem. 1974, 86, 50Ϫ51; An-
gew. Chem. Int. Ed. Engl. 1974, 13, 82Ϫ83.
Y. Ogawa, M. Shibasaki, Tetrahedron Lett. 1984, 25, 663Ϫ664.
Received February 1, 2001
[7]
[8]
[9]
1
C). Ϫ H NMR (90 MHz, CDCl3): δ ϭ 0.60Ϫ1.00 (m, 6 H, 2-, 6-
CH3), 0.98Ϫ2.10 (m, 29 H, 2-, 6-H, 3Ϫ5-, 7Ϫ16-H2, OH), 3.47 (dd,
J ϭ 2.6, 5.8 Hz, 2 H, 1-H2), 4.91Ϫ5.12 (m, 2 H, 18-Ha), 5.58Ϫ6.09
(m, 1 H, 17-H). Ϫ C20H40O (296.5): calcd. C 81.01, H 13.59; found
C 80.65, H 13.85.
[O01043]
3390
Eur. J. Org. Chem. 2001, 3385Ϫ3390