Catalytic asymmetric allylic transfer reactions for the Enantioselective synthesis of dienyl and enynyl alcohols

Article abstract of DOI:10.1002/1099-0690(200103)2001:6<1143::aid-ejoc1143>3.0.co;2-o

Efficient catalytic asymmetric allylic transfer reactions of achiral aldehydes with 2-ethynyl- and 2-ethenyl-2-propenyl-stannane promoted by BINOL-Ti^IV complex with synergetic reagent are achieved for the synthesis of homoenynyl- and dienyl alcohols with high levels of enantioselectivity. The range of enantioselectivity is 84-99% ee with good chemical yields. The application of catalytic asymmetric dienylation in a single operation was exemplified by the enantioselective synthesis of naturally occurring (-)-Ipsdienol and (-)-Ipsenol.

Full text of DOI:10.1002/1099-0690(200103)2001:6<1143::aid-ejoc1143>3.0.co;2-o

FULL PAPER
Catalytic Asymmetric Allylic Transfer Reactions for the Enantioselective
Synthesis of Dienyl and Enynyl Alcohols
Chan-Mo Yu,*[a] Miyoo Jeon,[a] Jae-Young Lee,[a] and Junha Jeon[a]
Keywords: Allylation / Asymmetric catalysis / Alcohols / Lewis acids / Titanium
Efficient catalytic asymmetric allylic transfer reactions of
range of enantioselectivity is 84−99% ee with good chemical
achiral aldehydes with 2-ethynyl- and 2-ethenyl-2-propenyl- yields. The application of catalytic asymmetric dienylation in
stannane promoted by BINOL-TiIV complex with synergetic
reagent are achieved for the synthesis of homoenynyl- and
dienyl alcohols with high levels of enantioselectivity. The
a single operation was exemplified by the enantioselective
synthesis of naturally occurring (−)-Ipsdienol and (−)-Ipsenol.
Introduction
ally active alcohols, we set out to determine the scope with
new allylic transfer reagents.
The availability of efficient synthetic methods for achiev-
ing absolute stereoselectivity in a catalytic process in the
production of enantiomerically pure compounds is of con-
siderable current interest in the field of synthetic
3]
chemistry.[1
In this regard, allylic transfer reactions pro-
vide excellent stereoselective routes for converting aldehydes
Scheme 1
7]
into the corresponding alcohols.[4
In the light of wide-
spread advances in catalytic methods for the synthesis of
chiral substances, the allylic transfer reaction of carbonyl
functionalities with chiral Lewis acid catalysts has led to
significant developments in the area of synthetic chem-
istry.[8] Although there have been several elegant reports re-
garding reinforcing catalytic ability for practical use in the
literature,[9,10] the scope of the catalytic allylic transfer reac-
tion still remains in its application with structurally simple
allyl systems. Recently, we reported two versions of the en-
antioselective synthesis of dienyl alcohols 1 based on an
accelerating strategy.[11,12] Our approach involves the use of
a BINOL-TiIV complex as a chiral promoter along with
iPrSBEt2 as an accelerating synergetic reagent that has re-
cently been shown to provide highly enantioselective ver-
Results and Discussion
The new reagent 4, a crucial compound in the present
research, was prepared from commercially available 2-
methyl-1-buten-3-yne in a single operation, purified by dis-
tillation, and was found to be stable upon storage. Treat-
ment of dilithiated 2-methyl-1-buten-3-yne, prepared ac-
cording to a literature procedure,[21,22] with Bu3SnCl (0.8
equiv.) at 78 °C in THF for 30 min. then workup (quench-
ing with pH 7 buffer solution at 78 °C followed by extrac-
tion with hexanes), afforded the crude product. After re-
moval of baseline impurities by filtration through Et3N-pre-
treated silica gel with hexane as eluent, a final purification
was effected by distillation (0.1 Torr, 88 °C, 64% yield). The
stage was thus set for the allylic transfer reaction of 4 with
aldehydes promoted by a Lewis acid catalyst. After examin-
sions of allylic transfer reactions of achiral aldehydes in the
16]
production of enantioenriched alcohols.[13
During the
course of our research program aimed at finding new re-
agents and realizing useful and practical ways to expand
the scope of allylic transfer reactions, we became quite in-
terested in the addition of the dienyl moiety to one carbon
homologated systems such as 2 and 3 (Scheme 1). The real-
ization of an efficient method for the synthesis of 2 and 3
should be valuable because the structures are featured in
many biologically relevant substances,[17] and many useful
ing several conditions based on our previous studies,[10
15]
the following observations were made: (i) a control experi-
ment revealed that the reaction proceeded only slowly in
the absence of a synergetic reagent (10 mol-% catalyst, 20
°C, 20 h, 32% yield); (ii) iPrSBEt2 was found to be quite
efficient in the catalytic process to speed up the reaction
rate (with 5 mol-% BINOL-TiIV, see Table 1);[23] (iii) a 1:1
˚
mixture of BINOL and Ti(OiPr)4 in the presence of 4 A
functional group transformations can be foreseen for enynyl
20]
and dienyl moieties.[18
With the notion that this investi-
molecular sieves proved to be the most efficient
27]
catalyst;[24
(iv) the reaction performed at 20 °C in
gation leads to the efficient synthesis of a number of optic-
PhCF3 resulted in optimal chemical yields and enantioselec-
tivities in comparison with other solvents such as CH2Cl2
and toluene. Under optimal conditions, the allylic transfer
reaction was carried out according to the following proced-
ure: The red-brown mixture of (S)-BINOL-TiIV complex (5
[a]
Department of Chemistry and BK-21 School of Molecular
Science, Sungkyunkwan University,
Suwon 440 746, Korea
Fax: (internat.) 82-31/290-7075
E-mail: cmyu@chem.skku.ac.kr
Eur. J. Org. Chem. 2001, 1143 1148
WILEY-VCH Verlag GmbH, 69451 Weinheim, 2001
1434 193X/01/0306 1143 $ 17.50 .50/0
1143

C.-M. Yu, M. Jeon, J.-Y. Lee, J. Jeon
FULL PAPER
mol-%) prepared from (S)-BINOL (0.05 equiv.) and freshly Table 2. Catalytic asymmetric dienylation of 8[a]
distilled Ti(OiPr)4 (0.05 equiv.) in PhCF3 at 25 °C for 3 h
was cooled to 20 °C, and 5 (R PhCH2CH2) was added.
To this mixture was added dropwise 4 (1.1 equiv.) in PhCF3
followed by 7 (1.2 equiv.) in PhCF3 with a gas-tight syringe
via a syringe pump over 1 h along the wall of the flask while
keeping the temperature below 20 °C. After 7 h at 20
°C, the mixture was quenched by the addition of a saturated
Compound
5 (R)
h
Yield [%]
ee [%]
aqueous NaHCO3. After work up, chromatography on sil-
ica gel gave 2a (R PhCH2CH2) in 83% yield with 93%
3a
3b
3c
3d
3e
3f
PhCH2CH2
nC6H13
5
78
81
53
88
74
91
97
93
91
93
96
91
5
ee. The reliability of the reaction was further examined with
a variety of aldehydes of varying steric and electronic envir-
onments. Reactions are generally complete after 7 h at 20
°C. As shown in Table 1, we observed that better chemical
yields and enantioselectivities were obtained with less-
hindered aldehydes, including alkynal, than with the more
bulky cyclohexanecarboxaldehyde.
cC6H11
10
5
5
5
Ph
PhCH CH
PhCϵC
[a]
All conditions were identical with the enynylation described in
Table 1.
thesis of naturally occurring ( )-Ipsdienol and ( )-Ipsenol
Table 1. Catalytic asymmetric enynylation of 4[a]
(Scheme 2), which are two of the aggregation pheromones
33]
isolated from the bark beetle Ips. paraconfusus.[30
Reac-
tion of 8 with 3-methyl-2-butenal under identical conditions
except with (R)-BINOL instead of (S)-BINOL afforded
Ipsdienol 9 (68% yield; 93% ee; [α]D23
15.1, EtOH). Sim-
ilarly, isovaleraldehyde was converted under the same con-
ditions to Ipsenol 10 (77% yield; 99% ee; [α]D25
EtOH).
17.9,
Compound
5 (R)
h
Yield [%][c]
ee [%][d]
2a
2b
2c
2d
2e
2f
PhCH2CH2
nC6H13
7
83
78
41
91
68
81
93
94
84
97
92
91
7
cC6H11
22
9
7
7
Ph
PhCH CH
PhCϵC
Scheme 2
[a]
[b]
All reactions were carried out at 20 °C in PhCF3.
(S)-
[c]
BINOL:Ti(OiPr)4
and purified products.
1:1 (5 mol-%).
Yields refer to isolated
[d]
Enantiomeric excess were determined
Conclusion
by preparation of ( )-MTPA ester derivatives, analysis by 500
1
MHz H NMR spectroscopy, and comparison with corresponding
diastereomers which were prepared from (R)-BINOL-TiIV (all ent-
ries) and by HPLC analysis using chiral column (Chiracel OD-H,
5% iPrOH in hexanes, entries 4,5).
In summary, an efficient catalytic protocol for the enanti-
oselective synthesis of enynyl and dienyl alcohols has been
developed, based on the use of chiral Lewis acid and syner-
getic reagent. For this purpose, two tin reagents were pre-
pared and proven to be efficient for allylic transfer reactions
with achiral aldehydes. A variety of aldehydes were con-
verted into the corresponding alcohols with high levels of
enantioselectivity. We believe that the products can serve as
synthetic intermediates for the synthesis of chiral sub-
stances by selective functional group transformations. Fur-
ther studies on the scope of this reaction and related trans-
formations are in progress.
In the light of the above results for the catalytic asymmet-
ric enynylation reaction, we turned our attention next to
examine the use of this approach with a dienyltin reagent
for the catalytic asymmetric dienylation reaction of alde-
hydes.[28] Treatment of 8[29] with 5 (R
PhCH2CH2, 1
equiv.) in the presence of (S)-BINOL-TiIV (5 mol-%) fol-
lowed by 7 in PhCF3 for 5 h afforded the alcohol 3a (R
Ph CH2CH2) in 78% isolated yield and 97% ee. From
Table 2 it can be seen that asymmetric dienylation reactions
were conducted on a variety of aldehydes under identical
conditions to furnish alcohols 3 with excellent enantioselec-
tivities. Reaction times and chemical yields were also de-
pendent on the steric environment of the substrates. The
absolute configuration of the predominating enantiomer for
adducts was unambiguously established by comparison of
values of specific rotations with those of previously known
alcohols.[28]
Experimental Section
General Remarks: All reactions were run in flame dried glassware
under an atmosphere of nitrogen. Tetrahydrofuran (THF) was
dried by refluxing over sodium and benzophenone until a perman-
ent purple coloration was presented, and distilled prior to use.
α,α,α-Trifluorotoluene was distilled from CaH2 prior to use. All
liquid reagents purchased from Aldrich were distilled properly
The direct synthetic application of catalytic asymmetric
dienylation was exemplified by the enantioselective syn- prior to use, unless otherwise indicated. Purification was conducted
1144 Eur. J. Org. Chem. 2001, 1143 1148

Catalytic Asymmetric Allylic Transfer Reactions
FULL PAPER
by flash column chromatography on silica gel (230 400 mesh),
eluting with a mixture of hexane and ethyl acetate, unless otherwise
stated. All reactions were monitored by thin layer chromatography
ature below 20 °C. After stirring for 7 h at 20 °C, aqueous
NaHCO3 (5 mL) was added to the reaction mixture, and then di-
luted with CH2Cl2 (20 mL). The molecular sieves were removed by
carried out on Merck silica gel plate (60 F254) using UV light as filtration, and the aqueous layer was extracted with CH2Cl2 (ca
visualizing agent and ethanolic anisaldehyde solution and heat as
developing agent. FT-IR spectra were recorded on a Nicolet 205.
1H NMR spectra were recorded on a Varian Unity Inova at
500 MHz in CDCl3 as a solvent with TMS or residual chloroform
as the internal standard. 13C NMR spectra were measured on a
Bruker AC-P200 at 50 MHz or on a Varian Unity Inova at
125 MHz in CDCl3 as a solvent. EI-mass spectra were obtained on 2921, 1608, 1496, 1296, 912 cm
a VG-Instrument Trio 2000 system at 70 eV. Optical rotations were
measured on a JASCO P-1020 digital polarimeter at ambient tem-
20 mL
2). After drying the combined organic solution over an-
hydrous Na2SO4, the solvents were removed under reduced pres-
sure. Column chromatography (SiO2, 15% EtOAc in hexanes) af-
forded 3 (R
less liquid. TLC: Rf 0.25 (15:85, EtOAc/hexane). [α]2D2
(c 1.55, CHCl3; 93% ee). FT-IR (neat): ν˜ 3408, 3296, 2941,
PhCH2CH2, 0.334 g, 0.167 mmol, 83%) as a color-
30.6
1
.
1H NMR (500 MHz, CDCl3):
1.79 1.85 (m, 3 H, PhCH2CH2 and OH), 2.30 (dd, J 8.65,
14.31 Hz, 1 H, HOCHCHHC C), 2.40 (dd, J 3.97, 14.31 Hz, 1
7.37, 9.07, 13.89 Hz,1 H,
δ
perature. Enantiomeric ratios were determined by preparation of H, HOCHCHHC C), 2.70 (ddd, J
1
(
)-MTPA ester derivatives, analysis by 500 MHz H NMR spec-
PhCHH), 2.84 (ddd, J 6.52, 9.07, 13.32 Hz, 1 H, PhCHH), 2.94
troscopy, and comparison with corresponding diastereomers which
were prepared from (R)-BINOL-TiIV and/or by HPLC analysis us-
ing a chiral column (Chiracel OD-H column, 5% iPrOH in hexanes,
UV 254 nm, flow 1.0 mL/min.).
(s, 1 H, CϵCH), 3.93 (m, 1 H, HOCH), 5.41 (s, 1 H, C CHH),
5.56 (d, J
1.79 Hz, 1 H, C CHH), 7.17 7.30 (m, 5 H, Ph).
31.98, 38.30, 45.06, 69.23,
13C NMR (125 MHz, CDCl3): δ
77.86, 83.60, 125.68, 125.76, 127.26, 128.31, 128.36, 141.93. EI-
MS: m/z 200 [M ]. C14H16O (200.28): calcd. C 83.96, H 8.05;
found C 84.01, H 8.13. [Diagnostic H NMR (CDCl3, 500 MHz)
1
Tributyl(2-methylene-but-3-ynyl)stannane (4): To
a solution of
freshly distilled 2-methyl-1-buten-3-yne (2.3 mL, 1.60 g, 24 mmol)
in dry THF (5 mL) were successively added BuLi (2.19  in hexane,
22 mL, 48 mmol) and tBuOK (5.2 g, 48 mmol) in THF (50 mL) at
78 °C under nitrogen atmosphere. After an additional 30 min. at
78 °C, the temperature was allowed to rise to 0 °C, and the mix-
ture was stirred at this temperature for 20 min. To the mixture was
of ( )-MTPA ester: δ 1.89 (M major), 2.02 (m minor) (m,
2 H, PhCH2CH2); 5.16 (M), 5.22 (m) (s, 1 H, C CHH)].
(؉)-(5R)-3-Methyleneundec-1-yn-5-ol (2b): Compound 2b was ob-
tained according to the above procedure for 2a as a colorless oil.
Yield: 78%.
TLC: Rf
0.33 (15:85, EtOAc/hexane).
[α]2D5
8.9 (c 1.64, CHCl3; 94% ee). FR-IR (neat): ν˜ 3385, 3306,
added
a solution of anhydrous LiBr (4.2 g, 48 mmol) in
1
2955, 2857, 1612, 1492, 1266, 1048, 909 cm
(500 MHz, CDCl3): δ 0.89 (t, J 6.81 Hz, 3 H, CH2CH3),
1.24 1.36 [m, 8 H, (CH2)4CH3], 1.46 1.50 (m, 2 H, HOCHCH2),
.
1H NMR
THF(25 mL) at 20 °C, and the mixture was stirred for 20 min. at
this temperature. After the mixture was cooled to 78 °C, preco-
oled Bu3SnCl (5.20 mL, 6.24 g, 19.2 mmol) in THF (5 mL) was ad-
ded with a cannula at the same temperature. After stirring for
1.74 (d, J
3.97 Hz, 1 H, OH), 2.24 (dd, J
8.79, 13.61 Hz, 1
H, HOCHCHHC C), 2.38 (dd, J
3.97, 13.61 Hz, 1 H,
30 min. at 78 °C, a buffer solution (pH
7, 20 mL) was added
HOCHCHHC C), 2.94 (s, 1 H, CϵCH), 3.89 (m, 1 H, HOCH),
5.41 (s, 1 H, C CHH), 5.56 (d, J 1.70 Hz, 1 H, C CHH).
13C NMR (50 MHz, CDCl3): δ 14.02, 22.56, 25.54, 29.24, 31.77,
36.71, 45.09, 69.78, 77.69, 83.72, 125.53, 128.73. EI-MS: m/z
162 [M H2O]. C12H20O (180.29): calcd. C 79.94, H 11.18;
found C 79.71, H 11.10. [Diagnostic H NMR (CDCl3, 500 MHz)
of ( )-MTPA ester: δ 1.89 (M), 2.02 (m) (m, 2 H, PhCH2CH2);
2.24 (M), 2.37 (m) (dd, 1 H, OCHCHH); 2.37 (m), 2.55 (M) (dd,
1 H, OCHCHH); 5.06 (M), 5.22 (m) (s, 1 H, C CHH)].
to the reaction mixture. The mixture was extracted with hexane
(ca. 150 mL 2). After drying the combined organic solution over
anhydrous Na2SO4, the solvents were removed under reduced pres-
sure. After removal of baseline impurities on a column with Et3N-
pretreated silica gel (ca 5 cm), distillation under reduced pressure
afforded 4 (4.36 g, 12.3 mmol, 64%) as a colorless liquid: b.p.
1
88 89 °C (0.1 Torr). TLC: Rf 0.67 (hexane). FR-IR (neat):
1
ν˜ 3290, 3031, 2955, 2923, 1611, 1452, 1267, 913, 754, 700 cm
.
1H NMR (500 MHz, CDCl3): δ
0.79 0.95 [m, 15 H,
Sn(CH2CH2CH2CH3)3], 1.26 1.34 [m,
6
H,
H, Sn(CH2CH2-
(؉)-(1S)-1-Cyclohexyl-3-methylene-pent-4-yn-1-ol (2c): Compound
2c was obtained according to the above procedure for 2a as a color-
CH2CH3)3],
1.44 1.54
[m,
6
Sn(CH2CH2-
CH2CH3)3], 1.90 (d, J 1.13 Hz, 2 H, SnCH2C CH2), 2.83 (s, 1
less oil. Yield: 41%.
[α]2D2
6.8 (c
3385, 3306, 2955, 2857, 1612, 1492, 1266, 1048, 909 cm
NMR (500 MHz, CDCl3): δ 1.05 1.22 (m, 6 H, cHex),
TLC: Rf
0.33 (15:85, EtOAc/hexane).
H, CϵCH), 5.04 (s, 1 H, C CHH), 5.10 (d, J 1.13 Hz, 1 H, C
0.87, CHCl3; 84% ee).
FR-IR (neat): ν˜
CHH).
13C NMR (50 MHz, CDCl3): δ
9.11, 13.73, 14.56,
C17H32Sn (355.13):
1
.
1H
26.98, 29.26, 73.04, 82.91, 123.83, 125.96.
calcd. C 57.49, H 9.08; found C 57.77, H 9.27.
1.40 1.55 (m, 2 H, cHex), 1.65 (br s, 1 H, OH), 1.71 1.80 (m, 2
H, cHex), 1.83 1.88 (m, 1 H, cHex), 2.22 (dd, J 9.64,14.20 Hz,
(؉)-(3R)-5-Methylene-1-phenylhept-6-yn-3-ol (2a): In a typical pro-
cedure for the allylic transfer reactions, a flame-dried flask con-
taining (S)-BINOL (114.6 mg, 0.4 mmol) and activated powdered
1 H, HOCHCHHC C), 2.38 (dd, J
HOCHCHHC C), 2.94 (s, 1 H, CϵCH), 3.66 (m, 1 H, HOCH),
5.41 (s, 1 H, C CHH), 5.56 (d, J 1.20 Hz, 1 H, C CHH).
13C NMR (50 MHz, CDCl3): δ 22.23, 25.94, 28.24, 29.45, 29.64,
31.77, 45.11, 69.83, 76.84, 83.54, 125.51, 129.35. EI-MS: m/z
178 [M ]. C12H18O (178.27): calcd. C 80.85, H 10.18; found C
80.47, H 10.40. [Diagnostic H NMR (CDCl3, 500 MHz) of ( )-
MTPA ester: δ 2.46 (M), 2.41 (m) (dd, 2 H, OCHCHH); 5.48
2.84, 14.20 Hz, 1 H,
˚
4 A molecular sieves (1.2 g) was evacuated, carefully purged with
nitrogen three times and then charged with dry PhCF3 (4 mL) fol-
lowed by freshly distilled Ti(OiPr)4 (freshly prepared 0.5  in
PhCF3, 0.8 mL, 0.4 mmol). The reaction was allowed to proceed
at 25 °C for 3 h. The red-brown mixture was cooled to 20 °C in a
dry ice/CCl4 bath, and hydrocinnamaldehyde (5, R PhCH2CH2,
0.27 g, 2.0 mmol) in PhCF3 (1.0 mL) was added. To this mixture
was added dropwise tributyl(2-methylenebut-3-ynyl)stannane (4,
0.78 g, 2.2 mmol) in PhCF3 (2 mL) followed by iPrSBEt2 (7, 0.35 g,
2.4 mmol) in PhCF3 (2 mL) with gas-tight syringe via a syringe
pump over 1 h along the wall of the flask while keeping the temper-
1
(M), 5.33 (m) (s, 1 H, C CH)].
(؉)-(1S)-3-Methylene-1-phenylpent-4-yn-1-ol (2d): Compound 2d
was obtained according to the above procedure for 2a as a colorless
oil. Yield: 91%.
TLC: Rf
1.63, CHCl3; 97% ee).
0.25 (15:85, EtOAc/hexane).
FR-IR (neat): ν˜
[α]2D5
20.4 (c
Eur. J. Org. Chem. 2001, 1143 1148
1145

C.-M. Yu, M. Jeon, J.-Y. Lee, J. Jeon
FULL PAPER
1
3381, 3290, 3031, 1611, 1452, 1050, 913, 754, 700 cm
.
1H
liquid: b.p. 94 96 °C (0.1 Torr). TLC: Rf 0.90 (85:15, hexane/
NMR (500 MHz, CDCl3): δ
2.55 2.59 (m, 2 H, HOCHCH2C C), 2.99 (s, 1 H, CϵCH), 5.00 959, 897, 863 cm
(ddd, J 3.11, 5.95, 7.65 Hz, 1 H, HOCH), 5.39 (s, 1 H, C
CHH), 5.56 (d, J 1.70 Hz, 1 H, C CHH), 7.25 7.42 (m, 5 H, Sn(CH2CH2CH2CH3)3),
Ph). 13C NMR (50 MHz, CDCl3): δ 47.17, 72.26, 78.04, 83.47, Sn(CH2CH2CH2CH3)3), 1.90 (d, J
125.82, 126.00, 127.10, 127.64, 128.43, 143.48. EI-MS: m/z CH2), 4.76 (d, J 0.85 Hz, 1 H, C CHH), 4.81 (s, 1 H, C CHH),
107 [M C5H5]. C12H12O (172.23): calcd. C 83.69, H 7.02; 5.05 (d, J 10.50 Hz, 1 H, H2C CH CHH), 5.09 (d, J
found C 83.55, H 7.38. [Diagnostic H NMR (CDCl3, 500 MHz) 17.29 Hz, 1 H, H2C
of )-MTPA ester: 2.46 (M), 2.59 (m) (dd, H, Hz, 1 H, H2C CH CH2).
HOCHCHHC C); 6.21 (M), 6.29 (m) (dd, 1 H, OCH)].
2.19 (d, J
3.11 Hz, 1 H, OH), EtOAc).
FR-IR (neat): ν˜
2963, 2933, 1649, 1638, 1461, 987,
1
.
1H NMR (500 MHz, CDCl3): δ
0.82 0.90 (m, 15 H, Sn(CH2CH2CH2CH3)3), 1.26 1.33 (m, 6 H,
1.44 1.50 (m, H,
0.85 Hz, 2 H, SnCH2C
6
C
1
C
CH CHH), 6.37 (dd, J
10.50, 17.29
(
δ
1
C
13C NMR (50 MHz, CDCl3): δ
9.28, 13.27, 13.45, 26.95, 28.95, 111.62, 112.50, 139.48, 146.11;
Calcd. for C17H34Sn: calcd. C 57.17, H 9.60; found C 57.59, H 9.85.
(؉)-(3S)-5-Methylene-1-phenylhept-1-en-6-yn-3-ol (2e): Compound
2e was obtained according to the above procedure for 2a as a color-
(؉)-(3R)-5-Methylene-1-phenyl-hept-6-en-3-ol (3a): Compound 3a
was obtained according to the procedure for the synthesis of 2a
less oil. Yield: 68%.
[α]2D5
29.2 (c
3583, 3422, 3298, 3054, 2956, 2925, 1611, 1448, 1266, 968 cm
1H NMR (500 MHz, CDCl3): δ 1.94 (d, J 3.69 Hz, 1 H, OH),
TLC: Rf
0.19 (15:85, EtOAc/hexane).
0.85, CHCl3; 92% ee).
FR-IR (neat): ν˜
except with 8 instead of 4. Yield: 78%.
TLC: Rf
1.70, EtOH; 97% ee).
3424, 3030, 2935, 1640, 1600, 1454, 993, 900
0.23 (15:85,
1
.
EtOAc/hexane).
[α]2D4
31.05 (c
FR-IR (neat): ν˜
1
2.45 2.53 (m, 2 H, HOCHCH2C C), 2.98 (s, 1 H, CϵCH), 4.62 cm
.
1H NMR (500 MHz, CDCl3): δ
1.81 1.85 (m, 2 H,
9.07, 14.17 Hz, 1
(m, 1 H, HOCH), 5.44 (s, 1 H, C CHH), 5.59 (d, J 1.14 Hz, 1
PhCH2CH2), 2.18 (s, 1 H, OH), 2.28 (dd, J
H, C CHH), 6.25 (dd, J 6.23, 15.87 Hz, 1 H, PhCH CH), 6.66 H, HOCHCHHC C), 2.53 (ddd, J
0.85, 3.69, 14.17 Hz, 1 H,
7.37, 9.07, 13.89 Hz, 1 H,
(d, J
15.87 Hz, 1 H, PhCH CH), 7.23 7.40 (m, 5 H, Ph).
45.20, 70.71, 77.99, 83.58,
HOCHCHHC C), 2.71 (ddd, J
13C NMR (50 MHz, CDCl3): δ
PhCHH), 2.85 (ddd, J 6.80, 8.79, 13.89 Hz, 1 H, PhCHH), 3.80
(m, 1 H, HOCHCH), 5.09 (dd, J 0.85, 1.14 Hz, 1 H, HHC
CH CH2), 5.12 (d, J 11.05 Hz, 1 H, H2C CH CHH),
1.14 Hz, 1 H, HHC CH CH2), 5.22 (d, J
17.57 Hz, 1 H, H2C CH CHH), 6.39 (dd, J 17.57, 11.05
Hz, 1 H, H2C CH CH2), 7.17 7.30 (m, 5 H, Ph).
13C
32.11, 38.78, 40.09, 69.08, 114.27,
125.56, 126.06, 126.48, 126.71, 127.64, 129.53 ,130.49, 131.00,
136.65. EI-MS: m/z 198 [M ]. C14H14O (198.26): calcd. C
C
C
84.81, H 7.12; found C 84.78, H 7.02. [Diagnostic 1H NMR 5.16 (d, J
C
(CDCl3, 500 MHz) of ( )-MTPA ester: δ 6.06 (M), 6.19 (m) (dd,
1 H, PhCH CH); 6.65 (M), 6.77 (n) (d, 1 H, PhCH CH)].
C
C
NMR (50 MHz, CDCl3): δ
(؉)-(3S)-5-Methylene-1-phenylhepta-1,6-diyn-3-ol (2f): Compound
2f was obtained according to the above procedure for 2a as a color-
118.38, 125.79, 128.37, 128.42, 138.44, 142.09, 143.01.
EI-MS:
m/z
found C 82.98, H 8.91. [Diagnostic H NMR (CDCl3, 500 MHz)
of ( )-MTPA ester: δ 2.46 (M), 2.37 (m) (m, 2 H, OCHCH2);
6.35 (M), 6.29 (n) (m, 1 H, H2C CH CH2)].
202 [M ].
C14H18O (202.30): calcd. C 83.12, H 8.97;
less oil. Yield: 81%.
TLC: Rf
1.10, CHCl3; 91% ee).
0.23 (15:85, EtOAc/hexane).
FR-IR (neat): ν˜
1
[α]2D5
31.5 (c
1
3583, 3422, 3298, 3054, 2956, 2925, 1611, 1448, 1266, 968 cm
.
C
1H NMR (500 MHz, CDCl3): δ
1.64 (br s, 1 H, OH), 2.68 (m,
2 H, HOCHCH2C C), 2.98 (s, 1 H, CϵCH), 4.90 (dd, J
6.41 Hz, 1 H, HOCH), 5.51 (s, 1 H, C CHH), 5.63 (d, J
Hz, 1 H, C CHH), 7.26 7.45 (m, 5 H, Ph).
6.41,
(؉)-(5R)-3-Methylene-1-undecen-5-ol (3b): Compound 3b was ob-
1.22 tained according to the procedure for the synthesis of 2a except
13C NMR
with 8 instead of 4. Yield: 81%. TLC: Rf 0.44 (15:85, EtOAc/
(50 MHz, CDCl3): δ
122.48, 125.78, 126.53, 128.46. 129.62, 131.50.
45.35, 61.32, 78.12, 83.29, 85.47, 88.95, hexane).
[α]2D4
6.35 (c
3449, 3409, 2927, 1655, 1631, 995, 903 cm
NMR (500 MHz, CDCl3): δ 0.86 0.90 (m, 5 H, CH2CH2CH3),
85.55, H 6.11. [Diagnostic 1H NMR (CDCl3, 500 MHz) of ( )- 1.28 1.33 (m,
H, CH2CH2CH2CH2CH3), 1.51 (m, H,
MTPA ester: δ 2.59 (M), 2.76 (m) (m, 2 H, OCHCH2); 6.03 (M), HOCHCHHCH2), 1.62 (d, J 3.11 Hz, 1 H, OH), 1.67 (m, 1 H,
0.93, EtOH; 93% ee).
FR-IR
.
1
EI-MS: m/z
(neat): ν˜
1H
196 [M ].
C14H12O (196.25): calcd. C 85.68, H 6.16; found C
6
1
6.08 (n) (dd, 1 H, OCHCH2)].
HOCHCHHCH2), 2.21 (dd,
HOCHCHHC CH2), 2.52 (ddd, J
HOCHCHHC CH2), 3.74 (m, 1 H, HOCHCH), 5.09 (dd, J
J
9.07, 13.89 Hz,
1.11, 3.69, 13.89 Hz, 1 H,
1 H,
Tributyl(2-methylene-but-3-enyl)stannane (8): A flame-dried flask
containing tBuOK (5.53 g, 49.2 mmol) was evacuated, carefully
purged with nitrogen three times and then charged with dry THF
(50 mL) followed by 2,2,6,6-tetramethylpiperidine (8.30 mL, 6.95 g,
49.2 mmol). The solution was cooled to 78 °C in a dry ice/acetone
bath, and a solution of nBuLi (2.41  in hexane, 20.5 mL,
49.4 mmol) was added over 10 min. while keeping the temperature
below 50 °C. After stirring for 20 min. at 78 °C, freshly distilled
2-methylbuta-1,3-diene (4.8 mL, 3.27 g, 48 mmol) in THF (10 mL)
was added over 10 min. during which time a deep red solution was
formed. After stirring at 78 °C for 30 min., precooled Bu3SnCl
(9.0 mL, 10.8 g, mL, 33.2 mmol) in THF (20 mL) was added with
a cannula at 78 °C. After stirring for 20 min. at 78 °C, a buffer
solution (pH 7, 20 mL) was added at the same temperature. The
mixture was extracted with hexane (ca. 150 mL 2). After drying
the combined organic solution over anhydrous Na2SO4, the sol-
vents were removed under reduced pressure. After removal of base-
line impurities by column chromatography with Et3N-pretreated
silica gel (ca. 5 cm) with hexane as eluent, distillation under re-
duced pressure afforded 8 (6.05 g, 16.9 mmol, 51%) as a colorless
1.11, 1.21 Hz, 1 H, HHC
C
CH CH2), 5.11 (d, J
10.78 Hz,
1 H, H2C CH CHH), 5.16 (d, J
C
1.21 Hz, 1 H, HHC
C
CH CH2), 5.25 (d, J 17.58 Hz, 1 H, H2C
6.40 (dd, J 10.78, 17.58 Hz, 1 H, H2C CH CH2).
NMR (50 MHz, CDCl3): δ 14.05, 22.56 25.71, 29.35, 31.64,
37.24, 40.08, 69.67, 114.1, 114.2, 138.54, 143.27. EI-MS: m/z
C
CH CHH),
C
13C
182 [M ]. C12H22O: calcd. C 79.06, H 12.16; found C 79.11, H
1
12.03. [Diagnostic H NMR (CDCl3, 500 MHz) of ( )-MTPA es-
ter: δ 2.46 (M), 2.37 (m) (m, 2 H, OCHCH2); 5.21 (M), 5.33 (m)
(m, 1 H, OCHCH2); 6.35 (M), 6.29 (m) (m, 1 H, H2C
C CH
CH2)].
(؊)-(1S)-1-Cyclohexyl-3-methylenepent-4-en-1-ol (3c): Compound
3c was obtained according to the procedure for the synthesis of 2a
except with 8 instead of 4. Yield: 53%.
EtOAc/hexane). [α]2D5
4.25 (c 0.63, EtOH; 91% ee). FR-
IR (neat): ν˜ 3405, 2926, 2854, 1650, 1600, 1450, 1029 cm
1H NMR (500 MHz, CDCl3): δ 1.06 1.30 (m, 6 H, cHex), 1.41
TLC: Rf
0.38 (15:85,
1
.
(m, 1 H, cHex), 1.59 (d, J
2.84 Hz, 1 H, OH), 1.68 (m, 1 H,
1146
Eur. J. Org. Chem. 2001, 1143 1148

Catalytic Asymmetric Allylic Transfer Reactions
FULL PAPER
cHex), 1.74 1.82 (m, 2 H, cHex), 1.89 (m, 1 H, cHex), 2.14 (dd, HHC
C
CH CH2), 5.34 (d, J
18.21 Hz, 1 H, HHC
J
10.20, 13.89 Hz, 1 H, HOCHCHH), 2.61 (dd, J 4.55,13.89
Hz, 1 H, HOCHCHH), 3.51 (m, 1 H, HOCHCH), 5.09 (d, J
1.23 Hz, 1 H, HHC CH CH2), 5.11 (d, J 11.05 Hz, 1 H, 40.24, 61.49, 83.22, 85.89, 114.20, 119.30, 122.67, 128.26, 128.40,
H2C CH CHH), 5.16 (d, J 1.23 Hz, 1 H, HHC CH 131.67, 139.31, 141.40. EI-MS: m/z 198 [M ]. C14H14O
CH2), 5.23 (d, J 17.57 Hz, 1 H, H2C CH CHH), 6.40 (dd, (198.26): calcd. C 84.81, H 7.12; found C 84.73, H 7.11. [Diagnostic
11.05, 17.57 Hz, 1 H, H2C CH CH2). 5.67 (M),
13C NMR 1H NMR (CDCl3, 500 MHz) of ( )-MTPA ester: δ
(50 MHz, CDCl3): δ 26.16, 28.44, 28.16, 29.03, 29.64, 36,83, 5.73 (m) (dd, 1 H, OCH); 6.38 (M), 6.31 (m) (dd, 1 H, H2C
43.53, 73.36, 114.10, 118.19, 138.39, 143.60. EI-MS: m/z 180
C
CH CH2), 6.43 (dd, J 18.21, 11.30 Hz, 1 H, H2C CH
C
CH), 7.26 7.41 (m, 5 H).
13C NMR (50 MHz, CDCl3): δ
C
C
C
C
J
C
C
CH CH2)].
)-(4R)-2-Methyl-6-Methyleneocta-2,7-dien-4-ol (9, Ipsdienol):
[M ]. C12H20O (180.29): calcd. C 79.94, H 11.08; found C 79.98,
H 10.93. [Diagnostic H NMR (CDCl3, 500 MHz) of ( )-MTPA
ester: δ 5.06 (M), 4.93 (m) (s, 1 H, HHC C); 6.35 (M), 6.28 (m)
(dd, 1 H, H2C
(
1
Ipsdienol was obtained according to the procedure for the synthesis
of 2a except with (R)-BINOL and 8 instead of 4. Yield: 68%.
C CH CH2)].
TLC: Rf 0.22 (15:85, EtOAc/hexane). [α]2D3
15.1 (c 1.12,
EtOH; 93% ee; ref.:[32] 13.2).
FR-IR (neat): ν˜
3440, 3080,
(؊)-(1S)-3-Methylene-1-phenyl-4-penten-1-ol (3d): Compound 3d
was obtained according to the procedure for the synthesis of 2a
except with 8 instead of 4. Yield: 88%.
2970, 2850, 1800, 1665, 1630, 1590, 1385, 1250, 1020, 1005, 990
1
1H NMR (500 MHz, CDCl3): δ 1.83 (s, 1 H, OH), 1.69
TLC: Rf
0.27 (15:85,
cm
.
EtOAc/hexane).
[α]2D5
24.08 (c
1.66, EtOH; 93% ee).
(d, J
1.21 Hz, 3 H, CH3MeC C), 1.73 (d, J
1.21 Hz, 3 H,
FR-IR (neat): ν˜
3408, 3386, 3087, 2927, 1595, 1453, 1094, 995,
MeCH3C C), 2.38 (dd, J
2.45 (dd, J
HOCHCH) 5.10 (d, J 1.01 Hz, 1 H, HHC
(d, J 10.54, 1 H, H2C CH CHH), 5.14 (d, J
H, HHC CH CH2), 5.21 (m, 1 H, Me2C CH), 5.28 (d, J
17.53 Hz, 1 H, H2C CH
1 H, H2C CH CH).
8.11, 14.17 Hz, 1 H, HOCHCHH),
1
903 cm
.
1H NMR (500 MHz, CDCl3): δ 2.13 (s, 1 H, OH),
7.68, 13.54 Hz, 1 H, HOCHCHH), 2.68 (dd, J
5.18, 14.17 Hz, 1 H, HOCHCHH), 4.52 (m, 1 H,
CH CH2), 5.12
1.01 Hz, 1
2.44 (dd, J
C
5.94,13.54 Hz, 1 H, HOCHCHH), 4.85 (m, 1 H, HOCHCH), 5.12
(d, J 1.05 Hz, 1 H, HHC CH CH2), 5.14 (d, J 11.01
Hz, 1 H, H2C CH CHH), 5.18 (d, J 1.05 Hz, 1 H, HHC
CH CH2), 5.34 (d, J 18.11 Hz, 1 H, H2C CH CHH),
6.43 (dd, J 18.11, 11.01 Hz, 1H, H2C CH CH2), 7.26 7.41
(m, 5 H, Ph). 42.20, 72.19,
13C NMR (50 MHz, CDCl3): δ
114.25, 118.80 125.75, 127.54, 128.41, 138.32, 142.73, 144.06.
EI-MS: m/z 174 [M ]. C12H14O (174.24): calcd. C 82.72, H
8.10; found C 82.63, H 9.81. [Diagnostic 1H NMR (CDCl3,
500 MHz) of ( )-MTPA ester: δ 5.05 (M), 4.87 (m) (s, 1 H,
HHC C); 6.08 (M), 6.15 (m) (dd, 1 H, OCHPh); 6.38 (M), 6.31
(m) (dd, 1 H, H2C CH CH2)].
C
C
C
C
C
CH), 6.41 (dd, J 10.54, 17.53 Hz,
13C NMR (50 MHz, CDCl3): δ
C
C
C
C
18.04, 25.39, 39.83, 66.45. 113.44, 118.15, 127.42, 134.4, 138.40,
149.3.
EI-MS: m/z
152 [M ].
C10H16O (152.24): calcd. C
78.90, H 10.59; found C 78.67, H 10.44. [Diagnostic 1H NMR
(CDCl3, 500 MHz) of ( )-MTPA ester: δ 6.32 (M), 6.28 (m) (dd,
1 H, H2C
C CH CH2)].
(
)-(4S)-2-Methyl-6-methyleneoct-7-en-4-ol (10, Ipsenol): Ipsenol
was obtained according to the procedure for the synthesis of 2a
C
except with (R)-BINOL and 8 instead of 4. Yield: 77%.
TLC:
1.08,
Rf
0.40 (15:85, EtOAc/hexane).
[α]2D5
17.9 (c
(؉)-(3S)-5-Methylene-1-phenylhepta-1,6-dien-3-ol (3e): Compound
3e was obtained according to the procedure for the synthesis of 2a
except with 8 instead of 4. Yield: 74%.
EtOH, 99% ee; ref.[33] 17.5).
FR-IR (neat): ν˜
3378, 3088,
1
2957, 2929, 2871, 1595, 1465, 1367, 900 cm
(500 MHz, CDCl3): δ 0.91 (d, J
0.93 (d, 6.53 Hz, H, MeCH3CH), 1.32 (m,
.
1H NMR
TLC: Rf
1.45, EtOH; 96% ee).
0.27 (15:85,
EtOAc/hexane).
[α]2D5
52.95 (c
6.52 Hz, 3 H, CH3MeCH),
H,
FR-IR (neat): ν˜
3421, 3084, 3028, 2930, 1654, 1593, 1025, 966,
J
3
1
1
902 cm
.
1H NMR (500 MHz, CDCl3): δ 2.04 (s, 1 H, OH),
8.50, 14.17 Hz, 1 H, HOCHCHH), 2.63 (dd, J
Me2CHCHH), 1.36 (ddd, J
Me2CHCHH), 1.58 (d, J
5.67, 8.79, 13.60 Hz, 1 H,
3.12 Hz, 1 H, OH), 1.83 (m, 1 H,
2.49 (dd, J
4.82, 14.17 Hz, 1 H, HOCHCHH), 4.47 (m, 1 H, HOCHCH), 5.15
(d, J 1.13 Hz, 1 H, HHC CH CH2), 5.16 (d, J 10.77
Hz, 1 H, H2C CH CHH), 5.21 (d, J 1.13 Hz, 1 H, HHC
CH CH2), 5.32 (d, J 17.57 Hz, 1 H, H2C CH CH),
6.26 (dd, J 6.24, 15.87 Hz, 1 H, PhCH CH), 6.43 (dd, J
17.57, 10.77 Hz, 1 H, H2C CH CH), 6.63 (d, J 15.87 Hz,
1 H, PhCH CH), 7.22 7.40 (m, 5 H, Ph). 13C NMR (50 MHz,
CDCl3): δ 40.09, 70.73, 114.29, 118.81, 126.46, 127.59, 128.53,
Me2CH), 2.21 (dd, J 9.07, 13.89 Hz, 1 H, HOCHCHHC CH2),
2.50 (dd, J 1.14, 3.40, 13.89 Hz, 1 H, HOCHCHHC CH2), 3.72
C
C
(m, 1 H, HOCHCH), 5.10 (d, J 0.55 Hz, 1 H, HHC
CH2), 5.12 (d, J 10.77 Hz, 1 H, H2C CH CHH), 5.17 (dd,
0.55, 1.14 Hz, 1 H, HHC CH CH2), 5.25 (d, J 17.58
Hz, 1 H, H2C CH CHH), 6.40 (dd, J 10.77, 17.85 Hz, 1 H,
H2C
CH CH2). 13C NMR (50 MHz, CDCl3) 22.25, 23.64,
24.87, 40.80, 46.68, 67.88, 114.59, 118.88, 139.07, 143.70. EI-
C CH
C
C
C
J
C
C
C
C
130.19, 131.65, 136.74, 138.44, 142.36. EI-MS: m/z 200 [M ].
C14H16O (200.28): calcd. C 83.96, H 8.05; found C 83.63, H
8.08. [Diagnostic 1H NMR (CDCl3, 500 MHz) of ( )-MTPA ester:
MS: m/z 154 [M ]. C10H18O (154.25): calcd. C 77.87, H 11.76;
found C 77.81, H 11.57. [Diagnostic H NMR (CDCl3, 500 MHz)
1
of
(
)-MTPA ester:
δ
2.33 (M), 2.41 (m) (dd,
1
H,
δ
5.83 (M), 5.91 (m) (dd, 1 H, OCH); 6.39 (M), 6.33 (m) (dd, 1
HOCHCHHC CH2); 6.31 (M), 6.36 (m) (dd, 1 H, H2C
C CH
H, H2C CH CH2); 6.59 (M), 6.68 (m) (d, 1 H, PhCH CH)].
C
CH2), virtually no minor diastereomers were detected].
(؉)-(3S)-5-Methylene-1-phenylhept-6-en-1-yn-3-ol (3f): Compound
3f was obtained according to the procedure for the synthesis of 2a
Acknowledgments
except with 8 instead of 4. Yield: 91%.
EtOAc/hexane). [α]2D3
57.5 (c 0.75, EtOH; 91% ee). FR-
IR (neat): ν˜ 3408, 3386, 3087, 2927, 1595, 1453, 1094, 995, 903
1H NMR (500 MHz, CDCl3): δ 1.84 (d, J 3.89, 1 H,
OH), 2.59 (dd, J 7.66, 14.17 Hz, 1 H, HOCHCHH), 2.67 (ddd,
1.13, 5.66, 14.17 Hz, 1 H, HOCHCHH), 4.82 (m, 1 H,
TLC: Rf
0.32 (15:85,
This research was supported by the Center for Molecular Design
and Synthesis (CMDS) at KAIST founded by a funding from the
Korea Science & Engineering Foundation (KOSEF Science Re-
search Center program).
1
cm
.
J
[1]
HOCHCH), 5.11 (d, J
5.16 (s, 1 H, H2C
11.30 Hz, 1 H, H2C
CH CHH), 5.19 (d, J
C
CH CHH),
R. Noyori, Asymmetric Catalysis in Organic Synthesis, Wiley,
1994, pp. 255 297.
C
1.13 Hz, 1 H,
Eur. J. Org. Chem. 2001, 1143 1148
1147

C.-M. Yu, M. Jeon, J.-Y. Lee, J. Jeon
FULL PAPER
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