Efficient syntheses of secondary and tertiary 2-aryl- and 2-heteroaryl- allyl alcohols

Article abstract of DOI:10.1021/jo980840k

Reactions of α-aryl-, α-heteroaryl-, and α-heteroatom-substituted masked alkenyllithiums with aldehydes and ketones provide a general method for the synthesis of allylic alcohols substituted with an aryl or heteroaryl in the β position and aryl, heteroaryl or alkyl substituents in the α position via a [1,4]-C→O silicon rearrangement. In the case of reactions with enolizable aldehydes and ketones, anhydrous CeCl₃ was used as an additive. High diastereoselectivities are observed for allyl alcohols produced from α-substituted aldehydes.

Full text of DOI:10.1021/jo980840k

9978
J . Org. Chem. 1998, 63, 9978-9982
Efficien t Syn th eses of Secon d a r y a n d Ter tia r y 2-Ar yl- a n d
2-Heter oa r yl-a llyl Alcoh ols
Alan R. Katritzky,* Dorin Toader, and Xiaojing Wang
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida,
Gainesville, Florida 32611-7200
Received May 4, 1998
Reactions of R-aryl-, R-heteroaryl-, and R-heteroatom-substituted masked alkenyllithiums with
aldehydes and ketones provide a general method for the synthesis of allylic alcohols substituted
with an aryl or heteroaryl in the â position and aryl, heteroaryl or alkyl substituents in the R
position via a [1,4]-CfO silicon rearrangement. In the case of reactions with enolizable aldehydes
and ketones, anhydrous CeCl3 was used as an additive. High diastereoselectivities are observed
for allyl alcohols produced from R-substituted aldehydes.
In tr od u ction
of allylic sulfoxides11 and of allylic hypoiodites prepared
in situ from the corresponding iodides;12 (viii) [1,4]-CfO
silicon rearrangements.13
Useful reagents that have been developed for the
synthesis of allyl alcohols include the following: (ix)
1-chloroalkyl phenyl sulfoxide via R,â-epoxyalkyl sulfox-
ides;14 (x) dimethylsulfonium methylide;15 (xi) R-lithio
selenoxides,16 (xii) R-(diphenylphosphinoyl)acetaldehydes
by the intermolecular pinacol cross-coupling with satu-
rated aldehydes;17 (xiii) â-acyloxy sulfones.18
A group of transition metal methods includes the
following: (xiv) metal-alkyne complexes of tantalum;19
(xv) alkene transfer from zirconium20 or boron21 to zinc
followed by addition to aldehydes or ketones; (xvi) alk-
enylzirconocene chlorides catalyzed by zinc bromide.22
Miscellaneous methods worthy of mention are (xvii)
transformations of allylsilanes into allyl alcohols via allyl
selenides23 and (xviii) reductive eliminations of γ-(phe-
nylthio)-â-nitro alcohols with tributyltin hydride.24
Most of the methods listed above provide allylic alco-
hols unsubstituted in the 2-position. The few available
methods which can provide 2-substituted allylic alcohols
are as follows: (vi) selective reduction of enones and
enals10 which are limited by the availability of the
starting materials; (xiv-xvi) transition metal methods
which suffer from occasional poor regiochemistry19 and
Allyl alcohols are substrates in many important syn-
thetic transformations including sigmatropic processes,1a
palladium-catalyzed π-allyl reactions,1b and asymmetric
epoxidations.1c Consequently, a large amount of work
has been aimed at building these versatile molecules and
it resulted in methods with considerable generality.
A major group of syntheses utilizes epoxides as a ready
source and includes the following: (i) rearrangements of
2,3-epoxy alcohols and their derivatives;2,3 (ii) reactions
of R,â-epoxyalkylsilanes with arylsulfonyl-stabilized an-
ions;4 (iii) heteroatom-assisted isomerizations of epoxides
promoted by bases;5 (iv) organopalladium addition to
unsaturated epoxides;6 (v) ring openings with organose-
lenium reagents followed by elimination,7 with iodotri-
methylsilane,8 or electrochemically.9
A second large group of methods is based on the (vi)
selective 1,2-reduction of R,â-unsaturated enals and
enones.10 Other important general methods involve
rearrangements: (vii) [2,3]-sigmatropic rearrangement
(1) (a) Wipf, P. In Comprehensive Organic Synthesis; Trost, B. M.,
Ed.; Pergamon Press: Oxford, U.K., 1991; Vol. 5, p 827. (b) Godleski,
S. A. In Comprehensive Organic Synthesis; Trost, B. M., Ed.; Pergamon
Press: Oxford, U.K., 1991; Vol. 4, p 585. (c) J ohnson, R. A.; Sharpless,
K. B. In Comprehensive Organic Synthesis; Trost, B. M., Ed.; Pergamon
Press: Oxford, U.K., 1991; Vol. 7, p 389.
(2) Yadav, J . S.; Shekharam, T.; Gadgil, V. R. J . Chem. Soc., Chem.
Commun. 1990, 843.
(3) Fujii, N.; Habashita, H.; Akaji, M.; Nakai, K.; Ibuka, T.;
Fujiwara, M.; Tamamura, H.; Yamamoto, Y. J . Chem. Soc., Perkin
Trans. 1 1996, 865 and references therein.
(4) (a) Masnyk, M.; Wicha, J . Tetrahedron Lett. 1988, 29, 2497. (b)
J ankowski, P.; Marczak, S.; Masnyk, M.; Wicha, J . J . Organomet.
Chem. 1991, 403, 49. (c) Masnyk, M.; Wicha, J . Chem. Ber. 1994, 127,
677.
(11) Evans, D. A.; Andrews, G. C. Acc. Chem. Res. 1974, 7, 147.
(12) Yamamoto, S.; Itani, H.; Tsuji, T.; Nagata, W. J . Am. Chem.
Soc. 1983, 105, 2908.
(13) (a) Tsukamoto, M.; Iio, H.; Tokoroyama, T. Tetrahedron Lett.
1985, 26, 4471. (b) Fujii, A.; Iio, H.; Tokoroyama, T. Synthesis 1995,
78.
(14) (a) Satoh, T.; Kaneko, Y.; Yamakawa, K. Tetrahedron Lett. 1986,
27, 2379. (b) Satoh, T.; Kaneko, Y.; Yamakawa, K. Bull. Chem. Soc.
J pn. 1986, 59, 2463.
(5) (a) Mordini, A.; Pecchi, S.; Capozzi, G.; Capperucci, A.;
Degl’Innocenti, A.; Reginato, G.; Ricci, A. J . Org. Chem. 1994, 59, 4784.
(b) Saravanan, P.; DattaGupta, A.; Bhuniya, D.; Singh, V. K. Tetra-
hedron 1997, 53, 1855.
(6) Larock, R. C.; Ilkka, S. J . Tetrahedron Lett. 1986, 27, 2211.
(7) Sharpless, K. B.; Lauer, R. F. J . Am. Chem. Soc. 1973, 95, 2697.
(8) Kraus, G. A.; Frazier, K. J . Org. Chem. 1980, 45, 2579.
(9) Uneyama, K.; Nisiyama, N.; Torii, S. Tetrahedron Lett. 1984,
25, 4137.
(10) (a) Nakano, T.; Umano, S.; Kino, Y.; Ishii, Y.; Ogawa, M. J .
Org. Chem. 1988, 53, 3752. (b) Nutaitis, C. F.; Bernardo, J . E. J . Org.
Chem. 1989, 54, 5629. (c) Ranu, B. C.; Das, A. R. J . Org. Chem. 1991,
56, 4796. (d) Fuller, J . C.; Stangeland, E. L.; Goralski, C. T.; Singaram,
B. Tetrahedron Lett. 1993, 34, 257. (e) Cha, J . S.; Kwon, O. O.; Kwon,
S. Y. Org. Prep. Proced. Int. 1996, 28, 355.
(15) Harnett, J . J .; Alcaraz, L.; Mioskowski, C.; Martel, J . P.; Le
Gall, T.; Shin, D.-S.; Falck, J . R. Tetrahedron Lett. 1994, 35, 2009.
(16) Reich, H. J .; Shah, S. K. J . Am. Chem. Soc. 1975, 97, 3250.
(17) Park, J .; Pedersen, S. F. J . Org. Chem. 1990, 55, 5924.
(18) Khripach, V. A.; Zhabinskii, V. N.; Zhernosek, E. V. Tetrahedron
Lett. 1995, 36, 607.
(19) Takai, K.; Kataoka, Y.; Utimoto, K. J . Org. Chem. 1990, 55,
1707.
(20) Wipf, P.; Xu, W. Tetrahedron Lett. 1994, 35, 5197.
(21) Srebnik, M. Tetrahedron Lett. 1991, 32, 2449.
(22) Zheng, B.; Srebnik, M. J . Org. Chem. 1995, 60, 3278.
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Lett. 1981, 22, 5285.
(24) Ono, N.; Kamimura, A.; Kaji, A. Tetrahedron Lett. 1984, 25,
5319.
10.1021/jo980840k CCC: $15.00 © 1998 American Chemical Society
Published on Web 11/26/1998

2-Aryl- and 2-Heteroarylallyl Alcohols
J . Org. Chem., Vol. 63, No. 26, 1998 9979
Sch em e 1a
Ta ble 1. Syn th esis of Tr im eth ylsilyl Allyl Eth er s 3a -j,
4, a n d 7
reacn conditionsa
temp (°C)/ additive/ yield
product
X
R1
R2
time (h)
equiv
(%)
3a
3b
3c
3d
3e
3f
3g
3h
3i
3j
4
2-FC6H4
2-FC6H4
2-FC6H4
2-FC6H4
2-FC6H4
2-FC6H4
4-MeC6H4
C6H5
H
H
H
3-MeOC6H4
2-MeOC6H4
CH2CH2C6H5
-(CH2)5-
i-Pr
c-C6H11
t-Bu
3-MeOC6H4
Ph
2-MeOC6H4
Ph
rt/16
90/5
rt
rt
rt
115/24
rt
rt
105/7
115/8
rt
52
22b
77
CeCl3/1 75
CeCl3/1 67
H
H
H
H
H
H
H
H
67
87
72
52
53b,c
70
56
4-Me2NC6H4
2-MeC6H4
Bt
7
2-FC6H4
CH(Me)Ph
120/1
a
All addition reactions were performed at -78 °C. These
b
reaction conditions refer to the rearrangement step. Significant
O-desilylation was observed, and the free allyl alcohol was isolated.
c Yield calculated on recovered material.
are limited by the availability of the precursors alkynes,20
boranes,21 or zirconocenes;22 (viii) the [1,4]-CfO silicon
rearrangement for 2-alkyl-substituted allylic alcohols,13b
which has not been applied yet to the 2-aryl analogues.
We have previously presented our preliminary results
of new masked (R-arylalkenyl)lithium reagents which can
be used for the synthesis of secondary allylic alcohols
Ta ble 2. Syn th esis of Allyl Alcoh ols 5a -j
reacn conditions
solvent/additive/ yield
product
X
R1
R2
time (h)
(%)
5a
5b
5c
5d
5e
5f
5g
5h
5i
2-FC6H4
2-FC6H4
2-FC6H4
2-FC6H4
H
H
H
H
2-MeOC6H4
a
40
97
93
CH2CH2C6H5 MeOH/H+/1
c-C6H11
i-Pr
THF/TBAF/4
THF/TBAF/3.5
MeOH/H+/1
THF/TBAF/2
MeOH/H+/2
silica gel
79
possessing an aryl substituent in the 2-position.25
A
2-FC6H4
-(CH2)5-
3-MeOC6H4
Ph
2-MeOC6H4
2-MeOC6H4
CH(Me)Ph
100
70b
48c
56d
46e
97
detailed account of that work together with the further
scope and limitations of this methodology is presented
herein.
2-MeC6H4
4-Me2NC6H4
5-Me-thien-2-yl
2-MeC6H4
2-FC6H4
H
H
H
H
H
a
5j
MeOH/H+/1
Resu lts a n d Discu ssion
Isolated after workup along with the silyl ether. b Overall yield
a
without isolation of 3. c Significant addition of methanol to the
Reagents 1a -d were prepared as previously de-
scribed.25 Three novel reagents 1e-g were prepared by
the lithiation of the corresponding methylenebenzotria-
zolyl substrates and nucleophilic displacement of chlorine
from (chloromethyl)trimethylsilane in good yields. Thus,
the electron-rich 1e, phenylthio 1f, and heteroaromatic
1g, precursors for masked R-substituted-alkenyllithiums,
are made available.
d
double bond was observed. Hydrolysis occurred during column
chromatography. e Yield calculated on recovered starting material.
for 5 h in the case of 3b or reflux in THF for 5 h in the
case of 5f (Experimental Section and Table 2). Even
harsher conditions are required when both the substrate
(o-anisaldehyde) and the reagent (1c) possess a substitu-
ent in the 2-position. Thus, heating at 115 °C for 8 h
was necessary to accomplish the rearrangement to afford
3j. However, significant retro-addition was observed in
this case and starting materials were recovered. A bulky
substituent in the R position of the alkoxide has a similar
effect, probably by preventing 2 from reaching the
appropriate conformation for the rearrangement. Thus
3f and 7 are obtained by heating at 115 °C for 24 h and
120 °C for 1 h, respectively. A fluorine atom in the
2-position shows no steric effect due to the short C-F
bond, and for 3a ,c-f the rearrangement takes place upon
warming to room temperature.
The fact that the preparation of 3i necessitated quite
harsh reaction conditions is puzzling since steric factors
cannot be invoked to explain this finding. The electron-
donating 4-(N,N-dimethylamino)phenyl is known to fa-
cilitate the ionization of the benzotriazole;27 therefore,
this reaction is controlled by conformational rather than
electronic factors. In the case of 1f (X ) SPh), the
phenylthio group is a better leaving group than benzo-
triazole; consequently the benzotriazolyl moiety is re-
tained in the allyl ether product 4.
When 0.1 M THF solutions of 1a -g were treated with
n-BuLi at -78 °C, the corresponding R-benzotriazolyl
carbanions were formed. These anions underwent quan-
titative addition to nonenolizable aldehydes and afforded
intermediate lithium alkoxides 2 (Scheme 1). The exist-
ence of these intermediates was proven by quenching the
reaction mixture with water at -78 °C. In most cases,
upon simple warming from -78 °C to room temperature,
lithium alkoxides 2 undergo a [1,4]-CfO Brook rear-
rangement13,26 where benzotriazole acts as a leaving
group (Scheme 1) and the trimethylsilyl ethers 3 are
obtained (Table 1). This process is most likely intramo-
lecular since the stereochemistry of the intermediate
alkoxides 2 dramatically influences the reaction condi-
tions required. When either the phenyl group of the
incoming nucleophile (as is the case with 1c) or of the
aromatic aldehyde (as is the case with 2-anisaldehyde)
possesses a bulky substituent in the 2- or 6-position, the
rearrangement of the alkoxide 2 needs to be accomplished
under harsher reaction conditions, i.e. heating at 90 °C
(25) Katritzky, A. R.; Toader, D. J . Am. Chem. Soc. 1997, 119, 9321.
(26) Brook, A. G.; Bassindale, A. R. Molecular Rearrangements of
Organosilicon Compounds. In Rearrangements in Ground and Excited
States; De Mayo, P., Ed.; Academic Press: New York, 1980; Vol. 2, p
149.
(27) Katritzky, A. R.; Toader, D.; Xie, L. J . Org. Chem. 1996, 61,
7571.

9980 J . Org. Chem., Vol. 63, No. 26, 1998
Katritzky et al.
Sch em e 2
Sch em e 3
The reactions involving enolizable aldehydes posed
some additional challenges due to the possibility of proton
abstraction by the hard alkanyl anion. While reactions
of hydrocinnamic aldehyde and cyclohexyl carboxalde-
hyde did not need any additives and the additions were
the predominant process, isobutyric aldehyde and cyclo-
hexanone underwent enolization. Formation of Ce(III)
reagent28 by transmetalation with 1 equiv of anhydrous
56% yield. Compound 8, formed in only a minute
amount, was not isolated but was detected in the 1H
NMR spectrum of the crude mixture. This high degree
of diastereoselectivity is probably due to the bulkiness
of the carbanion derived from 1b.
Con clu sion
29
Reactions of R-aryl-, R-heteroaryl-, and R-heteroatom-
substituted masked alkenyllithiums with aldehydes and
ketones provide a general method for the synthesis of
allylic alcohols substituted with an aryl or heteroaryl in
the â position and aryl, heteroaryl, or alkyl substituent
in the R position via a [1,4]-CfO silicon rearrangement.
The trimethylsilyl ethers of these allylic alcohols are
stable compounds and undergo cleavage of the O-Si bond
under basic or acidic conditions.
CeCl3 prevents the enolization, and addition to the
carbonyl is successfully accomplished to give allyl ethers
3d ,e in 75 and 67% yield, respectively (Table 1).
Allyl trimethylsilyl ethers 3a -i and 4 survive the
workup in most cases and can be isolated by chromatog-
raphy on silica gel. In the case of 2-thiophenyl-substi-
tuted allylic alcohol 5h , the intermediate silyl ether could
not be purified on silica gel due to complete hydrolysis
to afford the free alcohol (Table 2). Significant hydrolysis
was observed during workup of the reaction mixture in
the case of alcohol 5a . The 2 M NaOH aqueous solution
used for the extraction of benzotriazole caused partial
hydrolysis of the silyl ether. In other cases where the
silyl ether was isolated, the cleavage of Si-O bond was
accomplished with 1 M tetrabutylammonium fluoride
(TBAF) in THF at room temperature for 2-4 h in high
yields (Table 2). A procedure which did not isolate the
intermediate silyl ether afforded the allyl alcohol 5f in
70% overall yield (Table 2). The main drawback of the
TBAF procedure is the necessity of removing the tet-
rabutylammonium salt. A more convenient procedure for
the hydrolysis of silyl ethers is stirring the substrate with
a catalytic amount of p-toluenesulfonic acid in methanol
at room temperature. In this way 5b,e are obtained in
quantitative yield. When electron-rich substrate 3i was
subjected to hydrolysis in methanol under acidic cataly-
sis, the desired 5g was obtained in 48% yield (Table 2)
while adduct 6 was formed as a byproduct in 37% isolated
yield (Scheme 2). The formation of compound 6 can be
explained by a process which comprises the protonation
of the styrene followed by trapping of the carbocation by
the solvent. When 6 is treated with catalytic amounts
of acid in chloroform, it slowly reverts back to 5g.
Therefore, the TBAF procedure is recommended in case
of allyl trimethylsilyl ethers with an electron-rich aryl
group in the 2-position.
Exp er im en ta l Section
Gen er a l P r oced u r es. Melting points were determined
with a MEL-TEMP capillary melting point apparatus equipped
with a Fluke 51 digital thermometer. NMR spectra were
recorded in CDCl3 with tetramethylsilane as the internal
1
standard for H (300 MHz) or solvent as the internal standard
for 13C (75 MHz). THF was distilled from sodium/benzophe-
none under nitrogen immediately prior to use. All reactions
with air-sensitive compounds were carried out under an argon
atmosphere. Column chromatography was conducted with
silica gel 230-400. 1-(5-Methyl-2-thienyl)-1H-benzotriazole,
1-(4-dimethyaminobenzyl)-1H-benzotriazole,29 and 1a-d25 were
prepared according to previously reported procedures. Ceri-
um(III) chloride was dried under high vacuum as described
in the literature.28a
Gen er a l P r oced u r e for th e Syn th esis of Com p ou n d s
1e-g. n-BuLi (1.6 M, 2.5 mL, 4 mmol) was added to a solution
of the corresponding benzotriazolylarylmethane (4 mmol) in
THF (50 mL) at -78 °C under argon. After 15 min of stirring,
(chloromethyl)trimethylsilane (0.49 g, 4 mmol) was added. The
reaction mixture was allowed to warm to room temperature
overnight, before being washed with brine (2 × 20 mL) and
dried (MgSO4), and the solvent was removed under reduced
pressure. The crude oil was subjected to flash chromatography
with 3:1 hexanes/ethyl ether to give the pure product.
4-[1-(1H-1,2,3-Ben zotr iazol-1-yl)-2-(tr im eth ylsilyl)eth yl]-
N,N-d im eth yla n ilin e (1e): white microcrystals (89% yield),
mp 134.9-136.2 °C; 1H NMR δ 0.13 (s, 9H), 1.94-2.13 (m, 2H),
2.91 (s, 6H), 5.96 (t, J ) 8.0 Hz, 1H), 6.65 (d, J ) 8.0 Hz, 2H),
7.26(7.38 (m, 4H), 7.45 (d, J ) 7.8 Hz, 1H), 8.02 (d, J ) 7.7
Hz, 1H); 13C NMR δ -1.6 (3C), 23.3, 40.3 (2C), 61.1, 110.3,
112.2 (2C), 119.8, 123.5, 126.6, 127.8 (2C), 128.0, 132.1, 146.4,
150.2. Anal. Calcd for C19H26N4Si: C, 67.41; H, 7.74; N, 16.55.
Found: C, 67.45; H, 7.44; N, 16.61.
1-[1-(P h en ylth io)-2-(tr im eth ylsilyl)eth yl]-1H-1,2,3-ben -
zotr ia zole (1f): yellow prisms (74% yield), mp 64.5-65.5 °C;
1H NMR δ -0.01 (s, 9H), 1.70-1.79 (m, 1H), 1.92-2.00 (m,
1H), 6.32-6.37 (m, 1H), 7.00-7.16 (m, 5H), 7.34 (t, J ) 7.9
Hz, 1H), 7.45 (t, J ) 7.4 Hz, 1H), 7.75 (d, J ) 8.3 Hz, 1H),
8.00 (d, J ) 8.3 Hz, 1H); 13C NMR δ -1.8 (3C), 23.7, 65.6,
111.3, 120.0, 123.8, 126.8, 128.6, 128.8 (2C), 131.2, 131.7, 133.3
(2C), 146.6. Anal. Calcd for C17H21N3SSi: C, 62.34; H, 6.46;
N, 12.83. Found: C, 62.44; H, 6.66; N, 12.79.
To study the diastereoselectivity of the addition to the
carbonyl, the reaction of 1b was attempted with racemic
R-phenylpropionaldehyde (Scheme 3). The crude mixture
obtained after reaction was subjected to GC and GC-MS
analysis. A 13.3:1 ratio of two diastereomers with
molecular weight 328 and very similar fragmentation
patterns were found. According to the Felkin-Anh
model of nucleophilic attack on aldehyde, compound 7 is
most likely the major diastereomer and was isolated in
(28) Imamoto, T. In Comprehensive Organic Synthesis; Trost, B. M.,
Ed.; Pergamon Press: Oxford, U.K., 1991; Vol. 1, p 231.
(29) (a) Dimitrov, V.; Kostova, K.; Genov, M. Tetrahedron Lett. 1996,
37, 6787. (b) Evans, W. J .; Feldman, J . D.; Ziller, J . W. J . Am. Chem.
Soc. 1996, 118, 4581.
1-[1-(5-m et h ylt h iop h en -2-yl)-2-(t r im et h ylsilyl)et h yl]-
1H-1,2,3-ben zotr ia zole (1g): light yellow prisms (90% yield),

2-Aryl- and 2-Heteroarylallyl Alcohols
J . Org. Chem., Vol. 63, No. 26, 1998 9981
mp 78.4-80.3 °C (hexanes); 1H NMR δ (0.15 (s, 9H), 1.93 (dd,
J ) 14.6 and 7.4 Hz, 1H), 2.05 (dd, J ) 14.6 and 8.8 Hz, 1H),
2.38 (s, 3H), 6.28 (t, J ) 8.0 Hz, 1H), 6.56 (d, J ) 2.3 Hz, 1H),
6.88 (d, J ) 3.3 Hz, 1H), 7.32 (t, J ) 7.5 Hz, 1H), 7.40 (t, J )
7.0 Hz, 1H), 7.42 (d, J ) 8.2 Hz, 1H), 8.03 (d, J ) 8.3 Hz, 1H);
13C NMR δ (1.8, 15.2, 24.1, 57.0, 110.3, 120.0, 123.7, 124.6,
125.4, 126.9, 131.6, 140.3, 141.9, 146.5. Anal. Calcd for
C16H21N3SSi: C, 60.91; H, 6.71; N, 13.32. Found: C, 61.29;
H, 6.86; N, 12.97.
9H), 0.38 (d, J ) 6.8 Hz, 3H), 0.48 (d, J ) 6.6 Hz, 3H), 1.04-
1.18 (m, 1H), 4.01 (s, 1H), 4.82 (s, 1H), 5.09 (d, J ) 1.7 Hz,
1H), 6.59-6.71 (m, 2H), 6.80-6.90 (m, 2H); 13C NMR δ 0.2
(3C), 15.4, 20.2, 31.4, 78.6, 115.6 (d, J ) 22.8 Hz), 116.3, 123.9
(d, J ) 3.5 Hz), 128.8 (d, J ) 8.1 Hz), 128.9, 130.6 (d, J ) 4.5
Hz), 146.6, 159.8 (d, J ) 244.8 Hz). Anal. Calcd for C15H23
-
FOSi: C, 67.62; H, 8.70. Found: C, 67.75; H, 9.03.
{[1-Cycloh exyl-2-(2-flu or op h en yl)p r op -2-en yl]oxy}tr i-
m eth ylsila n e (3f): purified by column chromatography with
100:1 hexanes/ethyl acetate, colorless oil (67% yield); 1H NMR
δ 0.17 (s, 9H), 1.07-1.16 (m, 6H), 1.50-1.71 (m, 5H), 4.37 (s,
1H), 5.23 (s, 1H), 5.47 (s, 1H), 7.00-7.12 (m, 2H), 7.21-7.31
(m, 2H); 13C NMR δ 0.2 (3C), 26.2, 26.2, 26.5, 26.5, 30.7, 41.4,
78.7, 115.6 (d, J ) 23.0 Hz), 116.5, 123.9 (d, J ) 3.3 Hz), 128.7
(d, J ) 8.3 Hz), 128.9, 130.6 (d, J ) 4.4 Hz), 146.0, 159.8 (d, J
) 249.0 Hz). Anal. Calcd for C18H27FOSi: C, 70.54; H, 8.88.
Found: C, 70.41; H, 9.04.
Gen er a l P r oced u r e for th e Syn th esis of Com p ou n d s
3a -j, 4, 5a -i, a n d 7. The corresponding benzotriazole
derivative 1 (2 mmol) was dissolved in THF (20 mL) and cooled
to -78 °C, and n-BuLi in hexanes (1.6 M, 1.25 mL, 2 mmol)
was added. For the preparation of compounds 3d ,e, anhydrous
cerium(III) chloride (0.493 g, 2 mmol) was added. After 30
min of stirring, the corresponding aldehyde (2 mmol) was
added and the mixture was allowed to warm to room temper-
ature over 16 h. In the case of compounds 3b,f,i, and j the
solvent was distilled out under a stream of argon and the
remaining oil was heated at the temperature and for the time
indicated in Table 1 followed by the addition of methylene
chloride (40 mL). The reaction mixture was washed with brine
(2 × 20 mL) and dried in case of compounds 3a ,g,h and 4. In
case of 3b-f,i the reaction mixture was washed with sodium
hydroxide aqueous solution (2 M, 40 mL) and dried. After
solvent removal the remaining oil was subjected to flash
column chromatography with 5:1 hexanes/diethyl ether in the
case of 3a ,g,h and 4 to give the pure product. For all other
cases the chromatographic system is indicated individually.
Compound 5a was obtained alongside with 3b, and compound
5i was obtained alongside with 3j. Compound 5h was obtained
after the column chromatography due to desilylation.
{[2-(4-F lu or op h en yl)-1-(3-m et h oxyp h en yl)a llyl]oxy}-
tr im eth ylsila n e (3a ): colorless oil (52% yield); 1H NMR δ
0.11 (s, 9H), 3.71 (s, 3H), 5.35 (s, 1H), 5.44 (s, 1H), 5.54 (s,
1H), 6.71-6.73 (m, 1H), 6.84-6.90 (m, 4H), 7.14 (t, J ) 8.3
Hz, 1H), 7.21-7.26 (m, 2H); 13C NMR δ 0.0 (3C), 55.0, 77.0,
112.4 (d, J ) 5.9 Hz), 114.3, 114.5, 114.8, 119.1 (2C), 129.0 (d,
J ) 7.1 Hz, 2C), 135.5, 144.1, 149.8, 159.5, 162.1 (d, J ) 244.6
Hz). Anal. Calcd for C19H23FO2Si: C, 69.06; H, 7.01. Found:
C, 69.17; H, 7.34.
{[1-ter t-Bu tyl-2-(4-m eth ylp h en yl)-a llyl]oxy}tr im eth yl-
1
sila n e (3g): colorless oil (87% yield); H NMR δ 0.15 (s, 9H),
0.73 (s, 9H), 2.33 (s, 3H), 4.34 (s, 1H), 5.28 (s, 2H), 7.10 (d, J
) 8.0 Hz, 2H), 7.28 (d, J ) 8.0 Hz, 2H); 13C NMR δ 0.3 (3C),
21.1, 26.7 (3C), 36.5, 81.3, 115.9, 126.7 (2C), 128.9 (2C), 136.7,
140.3, 150.5. Anal. Calcd for C17H28OSi: C, 73.85; H, 10.21.
Found: C, 74.08; H, 10.42.
{[1-(3-Met h oxyp h en yl)-2-(4-m et h ylp h en yl)a llyl]oxy}-
tr im eth ylsila n e (3h ): colorless oil (72% yield); 1H NMR δ 0.11
(s, 9H), 2.27 (s, 3H), 3.74 (s, 3H), 5.40 (s, 1H), 5.44 (s, 1H),
5.57 (s, 1H), 6.72 (dd, J ) 8.4 and 1.8 Hz, 1H), 6.89-6.91 (m,
2H), 7.02 (d, J ) 8.0 Hz, 2H), 7.13-7.20 (m, 3H); 13C NMR δ
0.1 (3C), 21.0, 55.0, 76.7, 112.5 (2C), 113.5, 119.3, 127.1 (2C),
128.6 (2C), 128.9, 136.7, 136.9, 144.5, 150.5, 159.5. Anal.
Calcd for C20H26O2Si: C, 73.57; H, 8.03. Found: C, 73.97; H,
8.31.
N,N-Dim eth yl-4-((1-p h en yl[(tr im eth ylsilyl)oxy]m eth -
yl)eth en yl)a n ilin e (3i): purified by column chromatography
with 50:1hexanes/ethyl acetate, yellow oil (52% yield); 1H NMR
δ 0.60 (s, 9H), 3.28 (s, 6H), 5.86 (s, 1H), 5.87 (s, 1H), 6.10 (s,
1H), 7.10 (d, J ) 8.7 Hz, 2H), 7.62 (d, J ) 7.1 Hz, 2H), 7.67-
7.71 (m, 3H), 7.84 (d, J ) 7.4 Hz, 2H); 13C NMR δ 0.1 (3C),
40.2, 76.8, 111.1, 111.8, 126.7, 126.8, 127.3, 120.5, 127.8, 128.0,
143.1, 149.7, 150.0. Anal. Calcd for C20H27NOSi: C, 73.79;
H, 8.36; N, 4.30. Found: C, 73.51; H, 8.53; N, 4.40.
(2-(2-F lu or op h en yl)-1-[2-(m et h yloxy)p h en yl]p r op -2-
en yloxy)tr im eth ylsila n e (3b): purified by column chroma-
tography with 50:1 hexanes/ethyl acetate, colorless oil (22%
Tr im et h yl{[1-[2-(m et h yloxy)p h en yl]-2-(2-m et h ylp h e-
1
1
yield); H NMR δ 0.22 (s, 9H), 3.81 (s, 3H), 5.39 (s, 1H), 5.70
n yl)p r op -2-en yl]oxy}sila n e (3j): yellow oil (53% yield); H
(s, 1H), 6.25 (s, 1H), 6.89 (d, J ) 8.0 Hz, 1H), 7.04-7.16 (m,
3H), 7.21 (t, J ) 7.4 Hz, 1H), 7.30-7.35 (m, 2H), 7.59 (d, J )
7.6 Hz, 1H); 13C NMR δ -0.1 (3C), 55.2, 69.0, 110.2, 115.1 (d,
J ) 22.7 Hz), 115.3, 120.5, 123.4 (d, J ) 3.4 Hz), 128.2 (d, J )
13.4 Hz), 128.5 (d, J ) 8.1 Hz), 130.9 (d, J ) 4.4 Hz), 147.0,
156.3, 160.0 (d, J ) 245.1 Hz). Anal. Calcd for C19H23FO2Si:
C, 69.05; H, 7.02. Found: C, 69.08; H, 7.31.
{[2-(2-Flu or oph en yl)-1-(2-ph en yleth yl)pr op-2-en yl]oxy}-
tr im eth ylsila n e (3c): purified by column chromatography
with 100:1 hexanes/ethyl acetate, colorless oil (75% yield); 1H
NMR δ 0.19 (s, 9H), 1.60-1.83 (m, 2H), 2.50-2.60 (m, 1H),
2.70-2.80 (m, 1H), 4.62-4.64 (m, 1H), 5.20 (s, 1H), 5.57 (s,
1H), 6.99-7.14 (m, 4H), 7.19-7.26 (m, 5H); 13C NMR δ 0.1
(3C), 31.8, 38.4, 73.7, 115.4, 115.7, 124.0 (d, J ) 3.3 Hz), 125.6,
128.2, 128.4, 129.0 (d, J ) 8.1 Hz), 130.8 (d, J ) 4.4 Hz), 142.3,
147.5, 159.7 (d, J ) 245.1 Hz). Anal. Calcd for C20H25FOSi:
C, 73.13; H, 7.67. Found: C, 72.85; H, 7.87.
(1-[1-(2-F lu o r o p h e n y l)e t h e n y l]c y c lo h e x y lo x y )t r i-
m eth ylsila n e (3d ): purified by column chromatography with
hexanes, colorless oil (75% yield); 1H NMR δ -0.19 (s, 9H),
0.84-0.90 (m, 1H), 1.09 (br s, 3H), 1.16-1.36 (m, 7H), 4.74 (s,
1H), 5.24 (s, 1H), 6.61-6.69 (m, 2H), 6.80-6.87 (m, 1H), 6.90-
6.96 (m, 1H); 13C NMR δ 2.8 (3C), 22.6, 25.6, 37.8, 77.7, 115.3
(d, J ) 23.3 Hz), 116.8, 123.0 (d, J ) 3.2 Hz), 128.4 (d, J ) 8.0
Hz), 129.5 (d, J ) 16.2 Hz), 131.7 (d, J ) 3.5 Hz), 149.8, 159.8
(d, J ) 243.5 Hz). Anal. Calcd for C17H25FOSi: C, 69.81; H,
8.63. Found: C, 69.72; H, 8.89.
NMR δ 0.39 (s, 9H), 2.60 (s, 3H), 3.97 (s, 3H), 5.32 (s, 1H),
5.75 (s, 1H), 6.25 (s, 1H), 7.12 (d, J ) 8.3 Hz, 1H), 7.31(7.63
(m, 6H), 7.86 (d, J ) 7.5 Hz, 1H); 13C NMR δ (0.21, 19.5, 55.2,
70.2, 110.1, 113.3, 120.4, 124.6, 126.6, 127.9, 128.0, 129.4,
129.6, 131.1, 135.9, 140.8, 151.4, 159.0. Anal. Calcd for
C
20H26O2Si: C, 73.57; H, 8.03. Found: C, 73.51; H, 8.44.
{[2-[1-(1,2,3-Ben zot r ia zol-1-yl)]-1-(3-m et h oxyp h en yl)-
1
a llyl]oxy}tr im eth ylsila n e (4): colorless oil (70% yield); H
NMR δ 0.08 (s, 9H), 5.53 (s, 1H), 5.60 (s, 1H), 6.16 (s, 1H),
7.13-7.20 (m, 3H), 7.29-7.34 (m, 3H), 7.38-7.48 (m, 2H), 8.00
(d, J ) 8.3 Hz, 1H); 13C NMR δ -0.1 (3C), 74.2, 107.8, 110.5,
119.8, 124.0, 126.7 (2C), 127.8, 127.9, 128.1 (2C), 132.9, 140.4,
145.7, 146.4. Anal. Calcd for C18H21N3OSi: C, 66.84; H, 6.89;
N, 12.99. Found: C, 66.51; H, 6.89; N, 13.06.
2-(2-F lu or op h en yl)-1-[2-(m eth yloxy)p h en yl]p r op -2-en -
1
1-ol (5a ): yellow oil (40% yield); H NMR δ 3.12 (d, J ) 5.3
Hz, 1H), 3.90 (s, 3H), 5.49 (s, 1H), 5.69 (s, 1H), 6.04 (br s, 1H),
6.95-7.05 (m, 2H), 7.10-7.17 (m, 2H), 7.27-7.44 (m, 4H); 13
C
NMR δ 55.3, 71.9 (d, J ) 3.0 Hz), 110.7, 115.3 (d, J ) 22.7
Hz), 116.0, 123.6 (d, J ) 3.4 Hz), 128.1, 128.4, 128.8 (d, J )
6.2 Hz), 129.8, 130.4 (d, J ) 4.4 Hz), 146.2, 157.0, 159.7 (d, J
) 245.4 Hz). Anal. Calcd for C16H15FO2: C, 74.40; H, 5.85.
Found: C, 74.50; H, 5.98.
1-[2-(Meth yloxy)p h en yl]-2-(2-m eth ylp h en yl)p r op -2-en -
1-ol (5i): colorless oil (46%); 1H NMR δ 2.41 (s, 3H), 3.23 (d, J
) 6.7 Hz, 1H), 3.94 (s, 3H), 5.27 (s, 1H), 5.68 (s, 1H), 5.90 (d,
J ) 6.7 Hz, 1H), 7.05 (d, J ) 8.0 Hz, 1H), 7.13 (t, J ) 7.4 Hz,
1H), 7.22 (d, J ) 7.4 Hz, 1H), 7.28-7.35 (m, 3H), 7.43-7.49
(m, 2H); 13C NMR δ 19.4, 55.2, 73.5, 110.7, 113.8, 120.6, 124.9,
{[2-(2-Flu or oph en yl)-1-(1-m eth yleth yl)pr op-2-en yl]oxy}-
tr im eth ylsila n e (3e): purified by column chromatography
with hexanes, colorless oil (67% yield); 1H NMR δ -0.22 (s,

9982 J . Org. Chem., Vol. 63, No. 26, 1998
Katritzky et al.
126.9, 128.2, 128.6, 129.2, 129.8, 135.7, 140.3, 150.8, 156.9.
Anal. Calcd for C17H18O2: C, 80.28; H, 7.13. Found: C, 80.12;
H, 7.29.
(m, 10H), 5.03 (s, 1H), 5.58 (s, 1H), 7.01-7.11 (m, 2H), 7.16-
7.29 (m, 2H); 13C NMR δ 21.8, 25.4, 36.3, 73.6, 114.9, 115.2
(d, J ) 23.3 Hz), 123.2 (d, J ) 3.3 Hz), 128.7 (d, J ) 8.0 Hz),
128.9, 131.7 (d, J ) 4.0 Hz), 151.6, 159.6 (d, J ) 242.2 Hz).
Anal. Calcd for C14H17FO: C, 76.33; H, 7.78. Found: C, 76.19;
H, 8.03.
1-[2-(Meth yloxy)ph en yl]-2-(5-m eth ylth ioph en -2-yl)pr op-
2-en -1-ol (5h ): purified by column chromatography with 3:1
1
hexanes/ethyl acetate, dark-red oil (56%); H NMR δ 2.41 (s,
3H), 2.68 (d, J ) 4.9 Hz, 1H), 3.89 (s, 3H), 5.29 (s, 1H), 5.57
(s, 1H), 5.98 (d, J ) 4.7 Hz, 1H), 6.54 (d, J ) 2.8 Hz, 1H), 6.77
(d, J ) 3.4 Hz, 1H), 6.90-6.94 (m, 2H), 7.24-7.34 (m, 2H);
13C NMR δ 15.3, 55.5, 69.8, 110.6, 111.1, 120.8, 124.2, 125.4,
128.0, 129.1, 129.9, 138.8, 140.6, 142.8, 157.1. HRMS calcd
for C15H16O2S, 260.0810; found, m/e 260.0863.
2-[4-(Dim et h yla m in o)p h en yl]-1-p h en ylp r op -2-en -1-ol
(5g): microcrystals, mp 88.6-90.0 °C, (48% yield); 1H NMR δ
2.26 (br s, 1H), 2.88 (s, 6H), 5.28 (s, 1H), 5.43 (s, 1H), 5.66 (s,
1H), 6.59 (d, J ) 8.3 Hz, 2H), 7.21-7.32 (m, 5H), 7.41 (d, J )
6.8 Hz, 2H); 13C NMR δ 40.3, 75.7, 110.9, 112.1, 126.8, 126.9,
127.4, 127.5, 128.3, 142.2, 149.6, 150.0. Anal. Calcd for
2-(2-F lu or op h en yl)-1-(1-p h en yleth yl)p r op -2-en yl tr i-
m eth ylsilyl eth er (7): separated by column chromatography
C
17H19NO: C, 80.60; H, 7.56; N, 5.53. Found: C, 80.48; H,
7.87; N, 5.57.
1
with 50:1 hexanes/ethyl acetate, colorless oil (56%); H NMR
2-(2-F lu or op h en yl)-4-p h en ylp en t-1-en -3-ol (5j): colorless
oil (97% yield); 1H NMR δ 1.21 (d, J ) 6.9 Hz, 3H), 1.87 (br s,
1H), 2.78-2.81 (m, 1H), 4.81 (br s, 1H), 5.30 (s, 1H), 5.61 (s,
1H), 7.01(7.28 (m, 9H); 13C NMR δ 12.9, 42.8, 77.0, 115.7 (d, J
) 22.7 Hz), 116.5, 124.2 (d, J ) 3.3 Hz), 126.4, 127.9, 128.3,
129.2 (d, J ) 8.2 Hz), 130.4 (d, J ) 4.4 Hz), 144.3, 146.2, 159.7
(d, J ) 245.0 Hz). Anal. Calcd for C17H17FO: C, 79.66; H,
6.69. Found: C, 79.79; H, 6.91.
δ 0.14 (s, 9H), 1.45 (d, J ) 6.9 Hz, 3H), 2.93-3.00 (m, 1H),
5.04 (s, 1H), 5.55 (s, 1H), 5.85 (s, 1H), 7.32-7.45 (m, 4H), 7.49-
7.59 (m, 4H); 13C NMR δ -0.4, 11.8, 42.6, 78.0 (d, J ) 3.9 Hz),
115.7 (d, J ) 22.9 Hz), 116.4, 124.2 (d, J ) 3.4 Hz), 126.0,
127.9, 128.2, 129.0 (d, J ) 8.2 Hz), 130.5 (d, J ) 18.3 Hz),
145.1, 146.7, 159.7 (d, J ) 244.7 Hz). Anal. Calcd for C20H25
FOSi: C, 73.13; H, 7.67. Found: C, 73.44; H, 7.96.
-
P r ep a r a tion of 1-(3-Meth oxyp h en yl)-2-(2-m eth ylp h e-
n yl)-2-p r op en -1-ol (5f). 1-[1-(2-Methylphenyl)-2-(trimethyl-
silyl)ethyl]-1H-1,2,3-benzotriazole (1c) (0.619 g, 2 mmol) was
dissolved in THF (50 mL) and cooled to -78 °C, and n-BuLi
in hexanes (1.6 M, 1.25 mL, 2 mmol) was added. After 15 min
of stirring, 3-methoxybenzaldehyde (0.24 mL, 2 mmol) was
added, and the mixture was allowed to warm to room tem-
perature over 16 h and stirred under reflux for 5 h. The
reaction mixture was washed with brine (2 × 20 mL) and
dried. After solvent removal the remaining oil was dissolved
in TBAF in THF (1 M, 2.4 mL, 2.4 mmol) and stirred at room
temperature for 2 h. After solvent removal, the remaining oil
was subjected to flash column chromatography with 1:1
hexanes/diethyl ether to give the pure product (colorless oil,
0.36 g, 70%): 1H NMR δ 2.07 (s, 3H), 2.58 (br s, 1H), 3.65 (s,
3H), 5.01 (s, 1H), 5.30 (s, 1H), 5.56 (s, 1H), 6.73-6.79 (m, 3H),
6.86 (d, J ) 7.2 Hz, 1H), 6.99-7.15 (m, 4H); 13C NMR δ 19.5,
55.0, 77.2, 112.0, 113.4, 113.9, 119.1, 125.0, 127.1, 129.0, 129.1,
129.9, 135.8, 139.5, 143.2, 150.9, 159.3. Anal. Calcd for
2-[4-(Dim eth yla m in o)p h en yl]-2-(m eth yloxy)-1-p h en yl-
p r op a n -1-ol (6): white powder (37% yield); H NMR δ 3.12
1
(s, 6H), 3.27 (s, 3H), 3.62 (s, 1H), 4.95 (s, 1H), 6.81 (d, J ) 8.5
Hz, 2H), 7.00 (d, J ) 7.4 Hz, 2H), 7.15 (d, J ) 8.4 Hz, 2H),
7.26-7.28 (m, 3H); 13C NMR δ 14.0, 40.5, 50.2, 81.8, 82.8,
111.8, 127.0, 127.0, 127.5, 128.5, 138.9, 149.9. Anal. Calcd
for C18H23NO2: C, 75.76; H, 8.12; N, 4.91. Found: C, 75.34;
H, 8.21; N, 4.96.
Gen er a l P r oced u r e for th e P r ep a r a tion of Com p ou n d s
5c,d . Trimethylsilyl ether 3e or 3f (0.5 mmol) was dissolved
in THF (30 mL) followed by addition of TBAF solution in THF
(1 M, 0.7 mL, 0.7 mmol). The reaction mixture was stirred at
room temperature for the time shown in Table 2. The solvent
was removed under reduced pressure, and the remaining oil
was dissolved in methylene chloride. The organic layer was
washed with dilute aqueous hydrochloric acid solution (8%, 3
× 10 mL) and water (10 mL) and dried (Na2SO4). After the
solvent was removed under reduced pressure, the residue was
distilled with a Kugelro¨hr apparatus at 0.4 Torr and 110 °C.
C
17H18O2: C, 80.28; H, 7.13. Found: C, 80.09; H, 7.48.
Gen er a l P r oced u r e for th e P r ep a r a tion of Com p ou n d s
1-Cycloh exyl-2-(2-flu or op h en yl)p r op -2-en -1-ol (5c): col-
orless oil (93%); 1H NMR δ 0.96-1.24 (m, 4H), 1.31-1.40 (m,
1H), 1.63-1.82 (m, 6H), 4.37 (d, J ) 4.0 Hz, 1H), 5.30 (s, 1H),
5.54 (s, 1H), 7.03-7.15 (m, 2H), 7.25-7.31 (m, 2H); 13C NMR
δ 26.0, 26.3, 26.4, 26.6, 30.1, 41.4, 78.3 (d, J ) 2.5 Hz), 115.6
(d, J ) 22.9 Hz), 116.5, 124.0 (d, J ) 3.4 Hz), 128.5 (d, J )
15.3 Hz), 129.0 (d, J ) 8.5 Hz), 130.5 (d, J ) 4.1 Hz), 146.5,
159.7 (d, J ) 244.4 Hz). Anal. Calcd for C17H18FO: C, 76.89;
H, 8.17. Found: C, 76.52; H, 8.49.
2-(2-F lu or op h en yl)-4-m eth ylp en t-1-en -3-ol (5d ): color-
less oil (79%); 1H NMR δ 0.86 (d, J ) 6.8 Hz, 3H), 0.96 (d, J )
6.8 Hz, 3H), 1.62-1.70 (m, 1H), 2.00 (br s, 1H), 4.41 (d, J )
4.4 Hz, 1H), 5.29 (s, 1H), 5.56 (s, 1H), 7.02-7.13 (m, 2H), 7.23-
7.31 (m, 2H); 13C NMR δ 15.7, 19.7, 31.4, 78.4, 115.6 (d, J )
23.0 Hz), 116.2, 124.0, 128.5 (d, J ) 14.9 Hz), 129.0 (d, J )
8.4 Hz), 130.5 (d, J ) 4.0 Hz), 146.8, 159.7 (d, J ) 244.7 Hz).
Anal. Calcd for C12H15FO: C, 74.20; H, 7.78. Found: C, 74.10;
H, 8.11.
5b,e,g,j a n d 6. Silyl ether 3c, 3e, or 3i (1 mmol) was dissolved
in methanol (24 mL), and p-toluenesulfonic acid monohydrate
(0.08 g, 0.4 mmol) was added. The reaction mixture was
stirred at room temperature for 1 h, and the excess methanol
was removed under reduced pressure. The residue was
dissolved in methylene chloride (20 mL), washed with satu-
rated aqueous sodium bicarbonate solution (20 mL) and water
(20 mL), and dried (Na2SO4), and the solvent was removed
under reduced pressure to give the pure product.
2-(2-F lu or op h en yl)-5-p h en ylp en t-1-en -3-ol (5b): color-
less oil (97% yield); 1H NMR 1.57-1.81 (m, 2H), 2.19 (br s,
1H), 2.50-2.75 (m, 2H), 4.48 (t, J ) 6.6 Hz, 1H), 5.14 (s, 1H),
5.47 (s, 1H), 6.88-7.11 (m, 9H); 13C NMR δ 31.6, 37.4, 73.2,
115.4, 115.7, 124.0 (d, J ) 3.3 Hz), 125.7, 127.8 (d, J ) 15.1
Hz), 128.3 (d, J ) 7.6 Hz), 129.1 (d, J ) 8.1 Hz), 130.5 (d, J )
3.8 Hz), 141.8, 147.5, 159.6 (d, J ) 244.5 Hz). Anal. Calcd
for C17H17FO: C, 79.66; H, 6.69. Found: C, 79.38; H, 6.91.
1-[1-(2-F lu or op h en yl)eth en yl]cycloh exa n ol (5e): color-
less oil (100% yield); 1H NMR δ 1.08-1.20 (m, 1H), 1.52-1.73
J O980840K