Configuration-dependent ring opening of silyloxiranes: synthesis of functionalized alkenes or tetrahydrofurans

Article abstract of DOI:10.1002/ejoc.200900448

cis- and trans-Silyloxiranes with a potential tosylate or bromide leaving group in the β position are available by the diastereospecific reduction of the corresponding alkynes with DIBAL-H and hydrosilylation with silanes, respectively. In the reaction wi

Full text of DOI:10.1002/ejoc.200900448

FULL PAPER
DOI: 10.1002/ejoc.200900448
Configuration-Dependent Ring Opening of Silyloxiranes:
Synthesis of Functionalized Alkenes or Tetrahydrofurans
Jens Lange[a] and Ernst Schaumann*[a]
Keywords: Carbanions / Carbenes / Silanes / Oxygen heterocycles
cis- and trans-Silyloxiranes with a potential tosylate or bro-
mide leaving group in the β position are available by the dia-
stereospecific reduction of the corresponding alkynes with
DIBAL-H and hydrosilylation with silanes, respectively. In
the reaction with the anion of a silylthioacetal, the outcome
of the reaction is configuration dependent: the cis-oxiranes
add nucleophilic methanthiolate and give a cis-vinyl sulfide
unit in a Peterson olefination. In contrast, the trans-oxiranes
lead to functionalized tetrahydrofurans with silyl(methylthio)
substitution on the ring and in the exocyclic α position.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2009)
(R3 = silyl). In the expected ring-opening product 3 (R3 =
silyl) there may be an interesting competition of 1,3- and
1,4-silyl migration. However, the present study shows that
quite different reaction channels are available for the reac-
tion of carbanion 1 (e.g., 23–) and silyloxiranes 2 (R3 = silyl;
e.g., 8, 13, 15).
Introduction
The ease, reliability, and stereoselectivity of oxirane ring
opening by nucleophiles is well established[1–3] and may
even be considered as an example of “click chemistry”.[4]
The picture becomes more diverse if functionalized oxiranes
of type 2 (R3 = H) are employed and silyl-stabilized carban-
ions 1 are used as nucleophiles; here, cycloalkanes 4 are
formed in a domino process (Scheme 1).[5–7] In addition to
the use of alkyl- and aryl-substituted oxiranes, there is also
a rich chemistry of silyloxiranes.[8,9] A noteworthy feature is
the regioselectivity of silyloxirane ring opening, which usu-
ally occurs by nucleophilic attack on the silyl-substituted
carbon atom, that is, in a contrasteric fashion.[8,9] With this
background, it seemed to be of special interest to study the
effect of silyl substitution in functionalized silyloxiranes 2
Results and Discussion
Synthesis of cis-Silyloxiranes 8
Silyl substitution in oxiranes 2 (R3 = silyl) creates a new
stereocenter, giving rise to diastereomers. So it seemed de-
sirable to control the relative configuration at both oxirane
carbon atoms. Diastereoselective cis-reduction of alkynes
5a,b[10] was achieved by using Negishi’s method of DIBAL-
H reduction.[11] The hydroxy group was liberated in the us-
ual way by acid-catalyzed hydrolysis, and resulting enols
6a,b were tosylated to 7a,b in the presence of trimethyl-
ammonium chloride as catalyst;[12] we had observed earlier
that this method is particularly useful for tricky tosylation
Scheme 1. Domino synthesis of cycloalkanes 4 from silyl-substi-
tuted carbanions 1 and functionalized oxiranes 2.
[a] Institut für Organische Chemie, Technische Universität
Clausthal,
Leibnizstraße 6, 38678 Clausthal-Zellerfeld, Germany
Fax: +49-5323-722858
E-mail: ernst.schaumann@tu-clausthal.de
Scheme 2. Synthesis of cis-silyloxiranes.
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© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Eur. J. Org. Chem. 2009, 4674–4684

Synthesis of Functionalized Alkenes or Tetrahydrofurans
reactions.[13] Epoxidation of functionalized cis-vinylsilanes in product 16 (Scheme 4). Formation of 18 demonstrated a
7a,b to silyloxiranes 8a,b by m-CPBA was straightforward 1,3-silyl shift of the original oxirane silicon and a preference
(Scheme 2).
of thiophenoxide elimination for a Peterson reaction.
Synthesis of trans-Silyloxiranes 13 and 15
The trans arrangement of the substituents on oxirane tar-
gets 13 and 15 was again secured by a diastereoselective
alkyne reduction, here of 3-butynol (9), but now by using a
hydrosilylation approach with platinum on carbon as cata-
lyst (Scheme 3).[14,15] This gave the desired trans selectivity,
but provided a mixture of regioisomers 10/11, which could
conveniently be separated by chromatography after tosyl-
ation to give 12/13, again by employing the Tanabe
method.[12] Isolated tosylates 12 can be oxidized to give
trans-silyloxiranes 13 or treated with lithium bromide in
SN2 chemistry to give bromides 14 and finally by epoxid-
ation to give trans-silyloxiranes 15 with bromine as a poten-
tial leaving group.
Scheme 4. Model ring-opening reactions of silyloxiranes 8a and
13b.
The Peterson olefination step occurred more readily if
cyanide was used as nucleophile to give unsaturated nitrile
20, however, along with desilylated ring-opening product
21. The formation of vinylsilane 18 from oxirane 8a and
carbanion 17 shows that thiophenol was eliminated more
readily from the primary ring-opening product of type 22
than silanol in a Peterson olefination. This is in line with
the good leaving-group properties of thiophenol.[18]
Scheme 3. Synthesis of trans-oxiranes.
Reactions of cis-Silyloxiranes 8 with Silylthioacetal 23
In the domino process starting from carbanion 1 and ep-
oxy tosylate 2 (LG = Ts; Scheme 1), anion 23– was found
to react particularly smoothly.[5–7] So, 23– was also em-
ployed in the reaction with silyloxiranes 8, 13, and 15.
Model Ring-Opening Reactions of Oxiranes 8a and 13b
In model reactions, ring opening of cis-oxirane 8a and Using 8a,b, alkenyl sulfides 25 were isolated. So, thioacetal
trans-oxirane 13b by thiophenoxide as an example of a 23 reacted as a source of methanethiolate. The cis configu-
3
strong nucleophile and by a carbanion, respectively, was ration of 25 is suggested by a 9.3 Hz olefinic J coupling
tested. Diverse products 16, 18–21 were isolated, but all constant. Apparently, the steric screening of the oxiranes by
were apparently formed via intermediate 22, that is, by the the silyl substituent prevents attack of carbanion 23–. In-
usual contrasteric ring opening of silyloxiranes.[8,9] With stead, the reaction is probably initiated by oxirane ring
thiophenoxide, both epoxide ring opening and tosylate sub- opening by methanethiolate to give intermediate 26, which
stitution were observed to give bis(sulfide)s 16 and 19. Silyl suffers from a gauche interaction between the silyl group
migration was seen for the DMPS group to give 19, but and the alkyl chain. So, rapid rotation to intermediate 27
the reaction conditions allowed silanol elimination in the with a cis arrangement of the silyl group and the alkoxide
Peterson olefination step to be avoided.[9,16] Starting from oxygen atom will occur; syn elimination of silyloxide finally
oxirane 8a, the TMS group, which is known to migrate less gives cis-alkene 25. In a parallel reaction, the tosylate group
readily than DMPS,[17] was still found on the carbon atom was displaced by a second equivalent of 23– (Scheme 5).
Eur. J. Org. Chem. 2009, 4674–4684
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
4675

J. Lange, E. Schaumann
FULL PAPER
Reactions of trans-Silyloxiranes 13 and 15 with
Silylthioacetal 23
trans-Silyloxiranes 13 and 15 and carbanion 23– react
quite differently from the corresponding cis compounds
8a,b. In the main reaction product, the tosylate or bromide
leaving group is no longer present and one equivalent of
23– is incorporated, though the two methylthio groups are
nonequivalent in the 1H NMR spectra. Moreover, prochiral
methyl or methylene groups introduced by the silyl substitu-
ents in 13a,b and 15a,b are magnetically nonequivalent, in-
dicating their position on an asymmetric carbon atom. In
1
accord with the coupling pattern and H–13C correlation
analysis, the structure of tetrahydrofurans 28 is suggested.
These heterocycles are formed in fair yields as single dia-
stereomers from tosylates 13, but in better yields from bro-
mides 15 (Scheme 6). Chemical proof of structure can be
seen in the oxidation of tetrahydrofuran 28a with dimethyl-
dioxirane (DMDO) to dihydrofuran 31, where one meth-
ylthio group was oxidized to a sulfone, whereas the other
was eliminated probably as methanesulfinate.
Scheme 5. Ring opening of cis-silyloxiranes 8 by carbanion 23–.
The parallel product with the trapping of methanethio-
To account for the formation of tetrahydrofurans 28
late by 8 should be carbene 24 (Scheme 5). So far, a car- from silyloxiranes 13 and 15 we invoked again substitution
benoid reactivity of silylthioacetal anions had only been ob- of the leaving group by silylthioacetal unit 23– and opening
served for the corresponding phenylthio-substituted com- of the oxirane ring by methanethiolate to give intermediate
pounds, in which thiophenoxide is a potentially better leav- 29. In contrast to 26, this compound does not suffer from
ing group than methanethiolate in 23–.[19,20] However, car- gauche interactions and so there was no special driving
bene 24 can be generated independently from a diazo pre- force to rotate around the former oxirane C–C bond. This
cursor.[20] In the present reaction, no product of carbene gives room for SNi attack of the alkoxide on the silyl-
24 could be detected. Similar to the complex reaction of thioacetal unit to give the tetrahydrofuran ring of 28 and
carbethoxycarbene with 2-phenyloxirane,[21] carbene 24 to regenerate methanethiolate. However, in another mecha-
may enter diverse reaction pathways with 8 and so escape nism, methanethiolate opens the oxirane prior to the SN2
detection.
reaction between silylthioacetal anion 23– and the tosylate
Scheme 6. Ring opening of trans-silyloxiranes 13 and 15 by carbanion 23–.
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Eur. J. Org. Chem. 2009, 4674–4684

Synthesis of Functionalized Alkenes or Tetrahydrofurans
Merck 60 F254 precoated silica plates and spots were detected by
UV fluorescence quenching or by spraying with a solution of vanil-
lin/sulfuric acid in ethanol and subsequent heating. Flash
chromatography was performed with silica gel 60 (Merck, 230–
400 mesh). Ethyl acetate (EA) and petroleum ether (PE) with the
boiling range 60–70 °C were used in the separations. All solvents
were distilled before use. All reactions involving carbanions were
carried out under a nitrogen atmosphere. GC measurements were
done by using Hewlett Packard instruments HP 5890 II and HP
6890 with flame ionization detector and connected with integrator
or bromide leaving group. The formed alkoxide then has a
chance to displace the leaving group in an SNi process to
give an oxetane. Now, carbene 24 may add to the nucleo-
philic ring oxygen atom of the oxetane to give ylide 30 and
from there ring enlargement to tetrahydrofuran product 28.
This has precedent in similar oxetane ring-enlargement re-
actions.[22,23] Both mechanisms account for product forma-
tion and the diastereoselectivity of the reaction resulting
from stereospecific oxirane ring opening. However, the lat-
ter mechanism implies that cis-8 and trans-silyloxiranes 13 HP 3396. A 30-m capillary column DB-5 of J & W Scientific was
and 15 react with 23– by quite different mechanisms and so
may be less probable (Scheme 6).
used. Nitrogen was used as the carrier gas. Initial column pressure
was 1.3 bar. For GCMS coupling, helium was used as the carrier
gas.
Phenylsilyl-substituted silyloxiranes 13c,d and carbanion
23– yield phenylalkenes 34 and 35 when the reaction is run
1-Trimethylsilyl-4-(2-tetrahydropyranyloxy)-1-butyne (5a) by Silyl-
ation: Following a literature method,[10] a solution of BuLi (2.45 
in hexane, 2.91 mL, 7.13 mmol) was added dropwise to 1-(2-tetra-
hydropyranyloxy)-3-butyne (1.000 g, 6.48 mmol)[25] in absolute
THF (22 mL) at –78 °C under an atmosphere of nitrogen. After
stirring for 40 min, chlorotrimethylsilane (1.22 mL, 9.72 mmol) was
added dropwise at the same temperature. Stirring was continued
for 1.5 h, and the mixture warmed to room temperature overnight.
Ether (50 mL) and water (10 mL) were added, and after separation
of the layers the aqueous layer was extracted with diethyl ether
(2ϫ20 mL). The combined organic phase was dried (MgSO4) and
the solvent was removed under vacuum. The product was used as
such. Yield: 1.424 g (97%), with spectroscopic data as given in the
literature.[26]
at –78 °C or as side products in the reaction of 13d with
23– at 0 °C. We explain this by primary formation of hyper-
valent silyl species 32, which then undergoes phenyl transfer
from the silyl residue of the original silyloxirane to the
neighboring oxirane carbon atom. So, alkoxide 33 is formed
and allows Peterson olefination to alkene 34. Alkene 35
seems to be a secondary product formed by tosylate dis-
placement with anion 23–. The phenyl transfer from the sili-
con atom to the vicinal carbon atom has precedent in re-
lated reactions.[24]
Conclusions
1-Dimethylphenylsilyl-4-(2-tetrahydropyranyloxy)-1-butyne
(5b):
Prepared analogously from the alkyne (324 mg, 2.1 mmol), though
finally purified by flash chromatography (PE/EA, 5:1) to give a
yellowish oil. Yield: 381 mg (63%). H NMR (200 MHz, CDCl3):
δ = 0.36 (s, 6 H, SiCH3), 1.33–2.17 (m, 6 H, pyran-CH2), 2.50 (t,
J = 7.0 Hz, 2 H, CH2CH2OTHP), 3.27–3.97 (m, 4 H, CH2OTHP
and pyran-CH2), 4.58 (s, 1 H, pyran-CH), 7.20–7.72 (m, 5 H, Ar-
H) ppm.
The present work reveals a striking difference in the be-
havior of cis-8 and trans-silyloxiranes 13 and 15 towards
carbanion 23–, but in no case was a reaction observed that
is comparable to that shown by alkyl-substituted oxiranes 2
(Scheme 1). The underlying principle seems to be the steric
hindrance of the silyloxiranes. This apparently does not al-
low opening of the oxirane unit by bulky anion 23–, but
rather attack of methanethiolate as formed in the equilib-
rium with carbene 24 (Scheme 5).
1
cis-4-(Trimethylsilyl)-3-buten-1-ol (6a): Following
a
Negishi
method,[11]
a
DIBAL-H solution (1  in hexane, 6.92 mL,
6.92 mmol) was added dropwise to 5a (1.424 g, 6.29 mmol) in abso-
lute ether (20 mL) at 0 °C under an atmosphere of nitrogen. The
reaction mixture was warmed to room temperature over 30 min
and stirred for another 30 min. Then the mixture was heated at
reflux for 4 h. After cooling to 0 °C, the reaction was quenched
with 2  HCl. A deposit was removed by filtration and thoroughly
washed with diethyl ether. The organic phase was washed with sat-
urated NaHCO3 solution (2ϫ), saturated NaCl solution, and dried
(MgSO4). The solvent was evaporated under vacuum, the residue
was taken up in methanol (7 mL), and a tip of the spatula-size
amount of TsOH·H2O was added. The mixture was then stirred
overnight. After addition of saturated NaHCO3 solution/ether the
mixture was filtered, and the residue was washed thoroughly with
ether. The organic phase was washed with saturated NaCl solution
(2ϫ) and dried (MgSO4), and the solvent was removed under vac-
uum. Yield: 680 mg (75%) with spectroscopic data as given in
ref.[27]
Experimental Section
General: Melting points are uncorrected. H NMR and 13C NMR
1
spectra were recorded with Bruker Avance DPX 200 and Avance
400 instruments in CDCl3 as solvent. TMS (δ = 0.00 ppm) or the
signal of the solvent (CDCl3: δ = 7.26 ppm) served as internal stan-
dard in 1H NMR spectra. The solvent peak (CDCl3 at δ =
77.0 ppm) was used as reference for 13C spectra. For assignment of
the number of substituents attached to the specified carbon atom,
each carbon is described as + (primary or tertiary carbon), – (sec-
ondary carbon) or o (quaternary carbon), as determined by the
DEPT-135 method. When necessary, NMR spectroscopic data
were assigned by using H–H and C–H correlated spectra. MS were
recorded with a Varian instrument Saturn 2100T or Hewlett–Pack-
ard 5989B; high-resolution MS (HRMS) measurements were car-
ried out at the Institut für Organische Chemie, Leibniz Universität
Hannover. LRMS (ESI) spectra were recorded with a Hewlett
Packard/Agilent instrument LC-MSD Serie 1100 at a dry gas tem-
perature of 300 °C, a capillary voltage of 3000 V and a fragmentor
voltage of 0 V. Samples were dissolved in HPLC-grade methanol
and sprayed directly from methanol. IR spectra were recorded with
a Bruker Vektor 22 FTIR spectrometer. TLC was performed on
cis-4-(Dimethylphenylsilyl)-3-buten-1-ol (6b): Was prepared analo-
gously from 5b (380 mg, 1.32 mmol) to give 173 mg (64%) as a
yellow oil with spectroscopic data as in ref.[10]
cis-4-(Tosyloxy)-1-(trimethylsilyl)-1-butene (7a): Was prepared by
the method of Tanabe[12] to give a colorless oil (56%) with spectro-
scopic data as reported before.[27]
Eur. J. Org. Chem. 2009, 4674–4684
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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4677

J. Lange, E. Schaumann
FULL PAPER
cis-1-(Diphenylmethylsilyl)-4-(tosyloxy)-1-butene (7b): Was pre-
pared analogously to 7a from 6b (62 mg. 0.30 mmol) to give 7b
(81 mg, 73%) as a colorless oil. H NMR (200 MHz, CDCl3): δ =
1361, 1307, 1291, 1252, 1212, 1177, 1115, 1097, 1019, 978, 918,
880, 816, 780, 737, 704, 664 cm–1. MS (DCP, 70 eV): m/z (%) = 229
(19), 149 (16), 136 (12), 135 (100) [SiMe2Ph], 130 (24), 117 (12),
113 (45), 107 (10), 105 (14) [SiPh], 91 (74) [Bn], 85 (12), 83 (15), 75
(14) [C2H7OSi], 70 (28), 65 (35) [C5H5], 57 (12), 55 (10). HRMS
1
0.34 (s, 6 H, SiCH3), 2.37 (dq, J = 6.9, 1.3 Hz, 2 H, CH2CH2OTs),
2.45 (s, 3 H, CH3 of Ts), 3.93 (t, J = 6.8 Hz, 2 H, CH2OTs), 5.80
(dt, J = 14.1, 1.3 Hz, 1 H, SiCH=CH), 6.26 (dt, J = 14.3, 7.1 Hz,
1 H, SiCH=CH), 7.28–7.37 (m, 5 H, Ar-H), 7.45–7.52 (m, 2 H, Ar-
H), 7.71–7.79 (m, 2 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3):
δ = –1.1 (+, 2 C, SiCH3), 21.6 (+, 1 C, CH3 of Ts), 32.8 (–, 1 C,
CH2CH2OTs), 69.3 (–, 1 C, CH2OTs), 127.9 (+, 4 C, C-Ar), 129.0
(+, 1 C, SiCH=CH), 129.8 (+, 2 C, C-Ar), 131.5 (+, 1 C, C-Ar),
133.0 (q, 1 C, C-Ar), 133.6 (+, 2 C, C-Ar), 138.8 (q, 1 C, C-Ar),
143.2 (+, 1 C, SiCH=CH), 144.7 (q, 1 C, C-Ar) ppm. IR (NaCl):
(ESI): calcd. for C19H24O4SSi [M
399.1062.
+
Na]+ 399.1062; found
General Procedure for Hydrosilylation Using Pt/C: On the basis of
a literature procedure,[14] under an atmosphere of nitrogen, alkyne
9 (1 mmol) was introduced into a Schlenk tube together with the
silane (1 mmol) and a tip of a spatula-size amount of Pt/C, and the
mixture warmed to 90 °C for 7 h. After cooling, the mixture was
adsorbed to silica and purified by flash chromatography. The fol-
lowing compounds were obtained:
ν = 3068, 2957, 1600, 1495, 1428, 1362, 1307, 1250, 1176, 1112,
˜
1097, 1072, 1041, 1020, 967, 915, 819, 780, 733, 703, 664 cm–1. MS
(DCP, 70 eV): m/z (%) = 345 (15) [M+ – Me], 291 (14), 230 (10),
229 (70), 173 (20), 155 (14) [Ts], 149 (15), 145 (21), 135 (34) [Si-
Me2Ph], 131 (15), 130 (16), 121 (10), 113 (10), 105 (16) [SiPh], 92
(10), 91 (100) [Bn], 83 (11), 75 (10) [C2H7OSi], 65 (37) [C5H5], 59
(14). HRMS (ESI): calcd. for C19H24O3SSi [M + Na]+ 383.1113;
found 383.1111.
trans-1-(Triethylsilyl)-1-buten-4-ol (10a): A 3:1 mixture (881 mg,
68%) of 10a and 2-(triethylsilyl)-1-buten-4-ol (11a) was obtained
as a colorless liquid from 9 (0.4 mL, 5.28 mmol) and triethylsilane
after flash chromatography (PE/EA, 20:1). The spectroscopic data
of 10a were as given in ref.[28]
trans-1-(Dimethylphenylsilyl)-1-buten-4-ol (10b): Product 10b
(519 mg, 48%) was obtained as a colorless liquid along with a mix-
ture (582 mg) of 10b and 2-(dimethylphenylsilyl)-1-buten-4-ol (11b)
from 9 (0.4 mL, 5.28 mmol) and dimethylphenylsilane (0.82 mL,
5.28 mmol) by flash chromatography (PE/EA, 30:1; 20:1; 10:1). 1H
NMR (200 MHz, CDCl3): δ = 0.35 (s, 6 H, SiCH3), 1.51 (br. s, 1
H, OH), 2.44 (ddt, J = 6.2, 0.8 Hz, 2 H, CH2CH2OH), 3.71 (t, J
= 6.3 Hz, 2 H, CH2OH), 5.92 (dt, J = 18.7, 0.9 Hz, 1 H,
SiCH=CH), 6.11 (dt, J = 18.6, 6.0 Hz, 1 H, SiCH=CH), 7.32–7.39
(m, 3 H, Ar-H), 7.48–7.56 (m, 2 H, Ar-H) ppm. 13C NMR
(50 MHz, CDCl3): δ = –2.6 [+, 2 C, Si(CH3)2Ph], 40.0 (–, 1 C,
CH2CH2OH), 61.5 (–, 1 C, CH2OH), 127.8 (+, 2 C, C-Ar), 128.9
(+, 1 C, C-Ar), 131.6 (+, 1 C, SiCH=CH), 133.8 (+, 2 C, C-Ar),
138.7 (q, 1 C, C-Ar), 144.5 (+, 1 C, SiCH=CH) ppm. IR (NaCl):
cis-4-(Tosyloxy)-1-(trimethylsilyl)-1,2-epoxybutane (8a): A solution
of m-CPBA (1 mmol) in CH2Cl2 was added to a solution of the
vinylsilane (1 mmol) in CH2Cl2 at 0 °C. Then, the cooling bath was
removed, and the mixture stirred at room temperature overnight.
The resulting mixture was washed with saturated NaHCO3 solution
(1ϫ) and with aqueous Na2S2O3 solution (10%, 1ϫ) and then fi-
nally dried (MgSO4). The solvent was removed under vacuum, and
the residue was purified by flash chromatography to give the silyl-
oxiranes. Product 8a (448 mg, 93%) was obtained from 7a (457 mg,
1.53 mmol) as a colorless oil. 1H NMR (200 MHz, CDCl3): δ =
0.09 (s, 9 H, SiCH3), 1.65 (dt, J = 8.2, 6.0 Hz, 1 H, CH2CH2OTs),
1.72 (dt, J = 7.7, 5.7 Hz, 1 H, CH2CH2OTs), 2.19 (d, J = 5.1 Hz,
1 H, Me3SiCH), 2.45 (s, 3 H, CH3 of Ts), 3.12 (ddd, J = 7.7, 5.1,
4.3 Hz, 1 H, Me3SiCHCH), 4.14–4.22 (m, 2 H, CH2OTs), 7.35 (d,
J = 8.1 Hz, 2 H, Ar-H), 7.80 (d, J = 8.1 Hz, 2 H, Ar-H) ppm. 13C
NMR (50 MHz, CDCl3): δ = –1.9 (+, 3 C, SiCH3), 21.6 (+, 1 C,
CH3 of Ts), 31.3 (–, 1 C, CH2CH2OTs), 52.3 (+,1 C, Me3SiCH),
53.8 (+, 1 C, Me3SiCHCH), 68.0 (–, 1 C, CH2OTs), 127.9 (+, 2 C,
C-Ar), 129.9 (+, 2 C, C-Ar), 132.8 (q, 1 C, C-Ar), 144.9 (q, 1 C,
ν = 3346, 3068, 3050, 2955, 1953, 1881, 1817, 1618, 1427, 1335,
˜
1248, 1189, 1158, 1114, 1047, 988, 823, 783, 758, 731, 699,
638 cm–1. MS (DCP, 70 eV): m/z (%) = 191 (47) [M+ – Me], 178
(30), 163 (73), 161 (31), 145 (39), 137 (68), 135 (88) [SiMe2Ph], 130
(33), 129 (32) [M+ – Ph], 121 (51), 105 (37) [SiPh], 91 (37) [Bn], 75
[C2H7OSi]. HRMS (ESI): calcd. for C12H18OSi [M + Na]+
229.1025; found 229.1026.
C-Ar) ppm. IR (NaCl): ν = 2958, 2901, 1923, 1598, 1495, 1420,
˜
1363, 1307, 1291, 1251, 1211, 1177, 1146, 1120, 1097, 1045, 1019,
978, 919, 843, 760, 692, 664 cm–1. MS (DCP, 70 eV): m/z (%) = 155
(6) [Ts], 143 (11) [M+ – OTs], 142 (20), 129 (11), 91 (48) [Bn], 75
(20) [C2H7OSi], 74 (12), 73 (100) [TMS], 70 (13), 65 (20) [C5H5],
59 (14). HRMS (ESI): calcd. for C14H22O4SSi [M + Na +
MeCN]+ 378.1171; found 378.1176.
trans-1-(Diphenylmethylsilyl)-1-buten-4-ol (10c) and 2-(Diphenyl-
methylsilyl)-1-buten-4-ol (11c): Starting from 9 (0.4 mL, 5.28 mmol)
and methyldiphenylsilane (1.05 mL, 5.28 mmol) and after flash
chromatography (PE/EA, 15:1), 10c (1008 mg, 71%) and 11c
1
(336 mg, 26%) were isolated as colorless liquids. Data for 10c: H
NMR (200 MHz, CDCl3): δ = 0.63 (s, 3 H, SiCH3), 1.50 (br. s, 1
H, OH), 2.43–2.54 (m, 2 H, CH2CH2OH), 3.72 (t, J = 6.4 Hz, 2
H, CH2OH), 6.11–6.16 (m, 2 H, HC=C), 7.33–7.41 (m, 6 H, Ar-
H), 7.49–7.56 (m, 4 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3):
cis-1-(Dimethylphenylsilyl)-4-(tosyloxy)-1,2-epoxybutane (8b): Ac-
cording to the procedure given for 8a, product 8b (69 mg, 96%)
was obtained from 7b (69 mg, 0.19 mmol) as a yellowish oil. 1H
NMR (200 MHz, CDCl3): δ = 0.36 and 0.39 (each s, 3 H, SiCH3), δ = –3.8 (+, 1 C, SiCH3), 40.2 (–, 1 C, CH2CH2OH), 61.4 (–, 1 C,
1.49–1.66 (m, 1 H, CH2CH2OTs), 1.86 (ddt, J = 14.5, 7.2 Hz, 4.5 CH2OH), 127.8 (+, 4 C, C-Ar), 129.2 (+, 2 C, C-Ar), 129.4 (+, 1
H, 1 H, CH2CH2OTs), 2.39 (d, J = 5.1 Hz, 1 H, PhMe2SiCH), 2.45
(s, 3 H, CH3 of Ts), 3.14 (dt, J = 7.6, 4.8 Hz, 1 H, PhMe2SiCHCH),
4.06 (dd, J = 7.2, 5.6 Hz, 2 H, CH2OTs), 7.28–7.41 (m, 5 H, Ar-
C, SiCH=CH), 134.8 (+, 4 C, C-Ar), 136.6 (q, 2 C, C-Ar), 146.7
(+, 1 C, Ph MeSiCH=CH) ppm. IR (NaCl): ν = 3570, 3346, 3068,
˜
2
3048, 2998, 2955, 1957, 1885, 1821, 1737, 1616, 1589, 1567, 1486,
H), 7.46–7.56 (m, 2 H, Ar-H), 7.72–7.81 (m, 2 H, Ar-H) ppm. 13C 1428, 1328, 1251, 1218, 1190, 1157, 1112, 1046, 988, 853, 792, 735,
NMR (50 MHz, CDCl3): δ = –3.4 and –3.1 (each +, 1 C, SiCH3),
21.6 (+, 1 C, CH3 of Ts), 31.0 (–, 1 C, CH2CH2OTs), 50.0 (+, 1 C, 225 (25) [M+ – Me – C2H4], 223 (16) [M+ – C2H5O], 207 (11), 197
PhMe2SiCH), 53.9 (+, 1 C, PhMe2SiCHCH), 67.9 (–, 1 C,
(79) [SiMePh2], 191 (43) [M+ – Ph], 183 (29), 137 (100), 121 (32),
700, 663 cm–1. MS (DCP, 70 eV): m/z (%) = 253 (28) [M+ – Me],
CH2OTs), 127.9 (+, 2 C, C-Ar), 128.0 (+, 2 C, C-Ar), 129.6 (+, 1 105 (46) [SiPh], 91 (25) [Bn], 77 (18) [Ph]. HRMS (ESI): calcd. for
C, C-Ar), 129.9 (+, 2 C, C-Ar), 132.8 (q, 1 C, C-Ar), 133.8 (+, 2 C, C17H20OSi [M + Na]+ 291.1181; found 291.1188. Data for 11c: 1H
C-Ar), 136.3 (q, 1 C, C-Ar), 144.8 (q, 1 C, C-Ar) ppm. IR (NaCl): ν NMR (200 MHz, CDCl3): δ = 0.68 (s, 3 H, SiCH3), 1.42 (br. s, 1
˜
= 3069, 3049, 2958, 2925, 2182, 1921, 1770, 1727, 1598, 1495, 1428,
H, OH), 2.48 (t, J = 6.5 Hz, 2 H, CH2CH2OH), 3.56 (t, J = 6.6 Hz,
4678
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Eur. J. Org. Chem. 2009, 4674–4684

Synthesis of Functionalized Alkenes or Tetrahydrofurans
1 H, CH2OH), 5.54 (d, J = 2.7 Hz, 1 H, CH2=C), 5.93 (dt, J = 2.8,
[SiMe2Ph], 155 (11) [Ts], 91 (93) [Bn], 65 (38) [C5H5]. HRMS (ESI):
1.4 Hz, 1 H, CH2=C), 7.34–7.43 (m, 6 H, Ar-H), 7.49–7.57 (m, 4 calcd. for C24H26O3SSi [M + Na]+ 445.1270; found 445.1270.
H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ = –4.0 (+, 1 C,
trans-4-Tosyloxy-1-(triphenylsilyl)-1-butene (12d): According to the
SiCH3), 39.4 (–, 1 C, CH2CH2OH), 61.5 (–, 1 C, CH2OH), 127.9
procedure given for 7a,b, product 12d (284 mg, 96%) was obtained
(+, 4 C, C-Ar), 129.5 (+, 2 C, C-Ar), 131.2 (–, 1 C, CH2=C), 135.0
from 10d (200 mg, 0.61 mmol) after flash chromatography (PE/EA,
(+, 4 C, C-Ar), 135.5 (q, 2 C, C-Ar), 144.9 (q, 1 C, CH2=C) ppm.
20:1) as a colorless solid. M.p. 95 °C. 1H NMR (200 MHz, CDCl3):
IR (NaCl): ν = 3569, 3346, 3068, 3049, 3011, 2955, 1958, 1885,
˜
δ = 2.40 (s, 3 H, CH3 of Ts), 2.58 (dq, J = 6.5, 1.1 Hz, 2 H,
CH2CH2OTs), 4.12 (t, J = 6.7 Hz, 2 H, CH2OTs), 5.98 (dt, J =
18.5, 6.0 Hz, 1 H, Ph3SiCH=CH), 6.23 (dt, J = 18.5, 1.2 Hz, 1 H,
Ph3SiCH=CH), 8.31–7.50 (m, 17 H, Ar-H), 7.73 (d, J = 8.3 Hz, 2
H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ = 21.6 (+, 1 C, CH3
of Ts), 35.9 (–, 1 C, CH2CH2OTs), 68.7 (–, 1 C, CH2OTs), 127.9
(+, C-Ar), 128.3 (+, 1 C, Ph3SiCH=CH), 129.6 (+, C-Ar), 129.8
1823, 1774, 1655, 1589, 1567, 1486, 1428, 1327, 1305, 1252, 1218,
1191, 1157, 1111, 1045, 999, 936, 886, 855, 790, 727, 699, 679 cm–1.
MS (DCP, 70 eV): m/z (%) = 253 (15) [M+ – Me], 223 (3) [M+
–
C2H5O], 199 (56), 197 (89) [SiMePh2], 191 (43) [M+ – Ph], 137
(100), 105 (44) [SiPh], 91 (15) [Bn], 77 (26) [Ph]. HRMS (ESI):
calcd. for C17H20OSi ([M + Na]+) 291.1181; found 291.1179.
(+, C-Ar), 145.9 (+, 1 C, Ph SiCH=CH) ppm. IR (KBr): ν = 3064,
˜
3
trans-1-(Triphenylsilyl)-1-buten-4-ol (10d): Product 10d (328 mg,
47%) was obtained from 9 (0.16 mL, 2.10 mmol) and triphenylsi-
lane (548 mg, 2.10 mmol) after flash chromatography (PE/EA,
10:1). M.p. 113 °C. The spectroscopic data agree with the data in
ref.[28]
1617, 1596, 1484, 1427, 1359, 1189, 1178, 1157, 1112, 987, 927,
860, 819, 786, 744, 727, 705, 661 cm–1. HRMS (ESI): calcd. for
C29H28O3SSi [M + Na]+ 507.1426; found 507.1413.
trans-4-(Tosyloxy)-1-(triethylsilyl)-1,2-epoxybutane (13a): Accord-
ing to the procedure given for 8a,b, product 13a (178 mg, 81%) was
obtained from 12a (211 mg, 0.62 mmol) as a colorless liquid after
flash chromatography (PE/EA, 30:1). 1H NMR (200 MHz,
CDCl3): δ = 0.47–0.61 (m, 6 H, SiCH2CH3), 0.94 (t, J = 7.9 Hz, 9
H, SiCH2CH3), 1.78–2.03 (m, 2 H, CH2CH2OTs), 2.00 (d, J =
3.6 Hz, 1 H, Et3SiCH), 2.44 (s, 3 H, CH3 of Ts), 2.83 (ddd, J =
6.4, 4.5, 3.6 Hz, 1 H, Et3SiCHCH), 4.12–4.20 (m, 2 H, CH2OTs),
7.34 (d, J = 7.9 Hz, 2 H, Ar-H), 7.79 (d, J = 8.3 Hz, 2 H, Ar-H)
ppm. 13C NMR (50 MHz, CDCl3): δ = 1.7 (–, 3 C, SiCH2CH3),
7.2 (+, 3 C, SiCH2CH3), 21.6 (+, 1 C, CH3 of Ts), 33.8 (–, 1 C,
CH2CH2OTs), 48.4 (+, 1 C, Et3SiCH), 52.0 (+, 1 C, Et3SiCHCH),
67.6 (–, 1 C, CH2OTs), 127.9 (+, 2 C, C-Ar), 129.9 (+, 2 C, C-Ar),
trans-4-(Tosyloxy)-1-(triethylsilyl)-1-butene (12a): According to the
procedure given for 7a,b, product 12a (1.073 g, 78%) was obtained
from 10a (757 mg, 4.06 mmol) after flash chromatography (PE/EA,
40:1). The spectroscopic data agree with the values in ref.[29]
trans-1-(Dimethylphenylsilyl)-4-(tosyloxy)-1-butene (12b): Accord-
ing to the procedure given for 7a,b, product 12b (422 mg, 97%) was
obtained from 10b (249 mg, 1.21 mmol) as a colorless oil after flash
1
chromatography (PE/EA, 25:1). H NMR (200 MHz, CDCl3): δ =
0.30 (s, 6 H, SiCH3), 2.44 (s, 3 H, CH3 of Ts), 2.45–2.55 (m, 2 H,
CH2CH2OTs), 4.10 (t, J = 6.8 Hz, 2 H, CH2OTs), 5.81 (dt, J =
18.6, 1.3 Hz, 1 H, SiCH=CH), 5.95 (dt, J = 18.6, 5.2 Hz, 1 H,
SiCH=CH), 7.28–7.51 (m, 7 H, Ar-H), 7.78 (d, J = 8.3 Hz, 2 H,
Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ = –2.7 (+, 2 C, SiCH3),
21.6 (+, 1 C, CH3 of Ts), 35.7 (–, 1 C, CH2CH2OTs), 69.1 (–, 1 C,
CH2OTs), 127.8 (+, 2 C, C-Ar), 127.9 (+, 2 C, C-Ar), 129.0 (+, 1
C, C-Ar), 129.8 (+, 2 C, C-Ar), 132.2 (+, 1 C, SiCH=CH), 133.1
(q, 1 C, C-Ar), 133.7 (+, 2 C, C-Ar), 138.4 (q, 1 C, C-Ar), 141.8
132.9 (q, 1 C, C-Ar), 144.9 (q, 1 C, C-Ar) ppm. IR (NaCl): ν =
˜
2955, 2876, 1598, 1495, 1460, 1417, 1363, 1293, 1239, 1178, 1097,
1018, 977, 916, 872, 816, 738, 664 cm–1. MS (DCP, 70 eV): m/z (%)
= 327 (35) [M+ – Et], 257 (100), 185 (33) [M+ – OTs], 155 (16) [Ts],
149 (15), 115 (62) [SiEt3], 91 (54) [Bn], 87 (25), 65 (21) [C5H5], 59
(22). HRMS (ESI): calcd. for C17H28O4SSi [M + Na]+ 379.1375;
found 379.1376.
(+, 1 C, SiCH=CH), 144.7 (q, 1 C, C-Ar) ppm. IR (NaCl): ν =
˜
3068, 2956, 2899, 1618, 1598, 1495, 1427, 1364, 1307, 1249, 1211,
1176, 1113, 1098, 1042, 1020, 974, 918, 817, 784, 733, 701,
664 cm–1. MS (DCP, 70 eV): m/z (%) = 345 (8) [M+ – Me], 317 (21)
trans-1-(Dimethylphenylsilyl)-4-(tosyloxy)-1,2-epoxybutane (13b):
According to the procedure given for 8a,b, product 13b (186 mg,
91%) was obtained from 12b (196 mg, 0.54 mmol) as a colorless
oil after flash chromatography (PE/EA, 10:1). 1H NMR (200 MHz,
CDCl3): δ = 0.29 and 0.32 (each s, 3 H, SiCH3), 1.76–1.91 (m, 1
H, CH2CH2OTs), 1.93–2.08 (m, 1 H, CH2CH2OTs), 2.15 (d, J =
3.5 Hz, 1 H, PhMe2SiCH), 2.44 (s, 3 H, CH3 of Ts), 2.81 (ddd, J
= 6.4, 4.5, 3.4 Hz, 1 H, SiCHCH), 4.15 (dd, J = 6.9, 5.6 Hz, 2 H,
CH2OTs), 7.29–7.43 (m, 5 H, Ar-H), 7.48–7.56 (m, 2 H, Ar-H),
7.77 (d, J = 8.3 Hz, 2 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3):
δ = –5.3 and –5.2 (each +, 1 C, SiCH3), 21.6 (+, 1 C, CH3 of Ts),
33.5 (–, 1 C, CH2CH2OTs), 51.1 (+, 1 C, PhMe2SiCH), 52.6 (+, 1
C, SiCHCH), 67.5 (–, 1 C, CH2OTs), 127.9 (+, 2 C, C-Ar), 128.0
(+, 2 C, C-Ar), 129.6 (+, 1 C, C-Ar), 129.9 (+, 2 C, C-Ar), 132.8
(q, 1 C, C-Ar), 133.9 (+, 2 C, C-Ar), 135.7 (q, 1 C, C-Ar), 144.9
[M+ – Me – C2H4], 291 (48), 229 (100), 211 (12), 205 (14) [M+
–
Ts], 173 (13), 161 (18) [C10H13Si], 149 (11) [C9H13Si], 145 (14), 135
(33) [PhMe2Si], 131 (14), 130 (14), 91 (46) [Bn], 65 (17) [C5H5].
HRMS (ESI): calcd. for C19H24O3SSi [M + NH4]+ 378.1559; found
378.1557.
trans-1-(Diphenylmethylsilyl)-4-(tosyloxy)-1-butene (12c): Accord-
ing to the procedure given for 7a,b, product 12c (388 mg, 82%) was
obtained from 10c (300 mg, 1.12 mmol) as a colorless oil after flash
1
chromatography (PE/EA, 12:1). H NMR (200 MHz, CDCl3): δ =
0.58 (s, 3 H, SiCH3), 2.42 (s, 3 H, CH3 of Ts), 2.54 (dt, J = 6.7,
4.6 Hz, 2 H, CH2CH2OTs), 4.11 (t, J = 6.7 Hz, 2 H, CH2OTs),
5.95–6.01 (m, 2 H, SiCH=CH), 7.28–7.40 (m, 8 H, Ar-H), 7.41–
7.50 (m, 4 H, Ar-H), 7.75 (d, J = 8.3 Hz, 2 H, Ar-H) ppm. 13C
NMR (50 MHz, CDCl3): δ = –3.9 (+, 1 C, SiCH3), 21.6 (+, 1 C,
CH3 of Ts), 35.8 (–, 1 C, CH2CH2OTs), 68.9 (–, 1 C, CH2OTs),
127.8 (+, 4 C, C-Ar), 129.3 (+, 2 C, C-Ar), 129.8 (+, 2 C, C-Ar),
(q, 1 C, C-Ar) ppm. IR (NaCl): ν = 2960, 1598, 1428, 1361, 1293,
˜
1250, 1189, 1177, 1116, 1097, 1037, 976, 917, 872, 817, 789, 736,
704, 664 cm–1. HRMS (ESI): calcd. for C19H24O4SSi [M + Na]+
399.1062; found 399.1060.
130.1 (+, 1 C, C-Ar), 133.1 (q, 1 C, C-Ar), 134.8 (+, 4 C, C-Ar), trans-1-(Diphenylmethylsilyl)-4-(tosyloxy)-1,2-epoxybutane (13c):
136.2 (q, 2 C, C-Ar), 144.0 (+, 1 C, C-Ar), 144.7 (q, 1 C, C-Ar) According to the procedure given for 8a,b, product 13c (114 mg,
ppm. IR (NaCl): ν = 3068, 3048, 3022, 2958, 1959, 1822, 1726, 76%) was obtained from 12c (144 mg, 0.34 mmol) as a slightly yel-
˜
1618, 1598, 1488, 1428, 1362, 1307, 1292, 1253, 1217, 1176, 1112,
low oil after flash chromatography (PE/EA, 10:1). 1H NMR
(200 MHz, CDCl3): δ = 0.55 (s, 3 H, SiCH3), 1.78–2.13 (m, 2 H,
1042, 1020, 974, 918, 758, 701, 664 cm–1. MS (DCP, 70 eV): m/z
(%) = 353 (12) [M+ – C4H5O], 291 (100) [M+ – C9H7O], 197 (25) CH2CH2OTs), 2.41 (d, J = 3.6 Hz, 1 H, Ph2MeSiCH), 2.43 (s, 3 H,
Eur. J. Org. Chem. 2009, 4674–4684
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
4679

J. Lange, E. Schaumann
FULL PAPER
CH3 of Ts), 2.79 (ddd, J = 6.2, 4.6, 3.4 Hz, 1 H, SiCHCH), 4.10–
2 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ = –2.6 (+, 2 C,
4.18 (m, 2 H, CH2OTs), 7.26–7.45 (m, 8 H, Ar-H), 7.49–7.59 (m, SiCH3), 31.5 (–, 1 C, CH2Br), 39.7 (–, 1 C, CH2CH2Br), 127.8 (+,
4 H, Ar-H), 7.73 (d, J = 8.3 Hz, 2 H, Ar-H) ppm. 13C NMR
(50 MHz, CDCl3): δ = –6.4 (+, 1 C, SiCH3), 21.6 (+, 1 C, CH3 of
2 C, C-Ar), 129.0 (+, 1 C, C-Ar), 131.4 (+, 1 C, SiCH=CH), 133.8
(+, 2 C, C-Ar), 138.6 (q, 1 C, C-Ar), 144.5 (+, 1 C, SiCH=CH)
Ts), 33.3 (–, 1 C, CH2CH2OTs), 50.3 (+, 1 C, Ph2MeSiCH), 52.6 ppm. IR (NaCl): ν = 3068, 3049, 2957, 1615, 1487, 1427, 1330,
˜
(+, 1 C, SiCHCH), 67.4 (–, 1 C, CH2OTs), 127.9 (+, 2 C, C-Ar), 1273, 1248, 1205, 1113, 991, 911, 841, 785, 731, 699, 637 cm–1. GC–
128.0 (+, 4 C, C-Ar), 129.9 (+, 4 C, C-Ar), 132.8 (q, 1 C, C-Ar), MS (70eV): m/z (%) = 253 (9) [M+ – Me], 240 (14) [M+ – 2Me],
133.6 (q, 1 C, C-Ar), 133.8 (q, 1 C, C-Ar), 134.8 (+, 4 C, C-Ar), 190 (19), 189 (100) [M+ – Br], 161 (15) [M+ – Br – C2H4], 135 (12)
144.8 (q, 1 C, C-Ar) ppm. IR (NaCl): ν = 3069, 2962, 1893, 1735,
[SiMe2Ph]. HRMS (EI): calcd. for C11H14BrSi [M – Me]+ 253.0048;
˜
1598, 1489, 1428, 1361, 1293, 1253, 1177, 1115, 1037, 975, 917,
871, 790, 731, 701, 664 cm–1. MS (DCP, 70 eV): m/z (%) = 361 (11)
[M+ – Ph], 291 (24), 267 (4) [M+ – OTs], 197 (100) [SiMePh2], 175
(42), 155 (8) [Ts], 130 (23), 105 (13) [SiPh], 91 (41) [Bn], 65 (16)
[C5H5]. HRMS (ESI): calcd. for C24H26O4SSi [M + Na]+ 461.1219;
found 461.1218.
found 253.0046.
trans-4-Bromo-1-(methyldiphenylsilyl)-1-butene (14c): According to
the procedure given for 14a, product 14c (277 mg, 92%) was ob-
tained as a slightly yellowish oil. H NMR (200 MHz, CDCl3): δ
= 0.64 (s, 3 H, SiCH3), 2.71–2.82 (m, 2 H, CH2CH2Br), 3.45 (t, J
= 7.0 Hz, 2 H, CH2Br), 6.07–6.12 (m, 2 H, SiCH=CH), 7.33–7.42
(m, 6 H, Ar-H), 7.50–7.58 (m, 4 H, Ar-H) ppm. 13C NMR
(50 MHz, CDCl3): δ = –3.8 (+, 1 C, SiCH3), 31.4 (–, 1 C, CH2Br),
39.7 (–, 1 C, CH2CH2Br), 127.8 (+, 4 C, C-Ar), 129.3 (+, 2 C, C-
Ar), 129.3 (+, 1 C, SiCH=CH), 134.8 (+, 4 C, C-Ar), 136.4 (q, 2
1
trans-4-(Tosyloxy)-1-(triphenylsilyl)-1,2-epoxybutane (13d): Accord-
ing to the procedure given for 8a,b, product 13d (226 mg, 85%) was
obtained from 12d (257 mg, 0.53 mmol) as a colorless solid after
flash chromatography (PE/EA, 10:1). M.p. 118 °C. 1H NMR
(200 MHz, CDCl3): δ = 1.87–2.08 (m, 2 H, CH2CH2OTs), 2.42 (s,
3 H, CH3 of Ts), 2.69 (d, J = 3.3 Hz, 1 H Ph3SiCH), 2.79 (ddd, J
= 6.0, 4.7, 3.4 Hz, 1 H, Ph3SiCHCH), 4.07–4.21 (m, 2 H, CH2OTs),
7.20–8.13 (m, 19 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ =
21.6 (+, 1 C, CH3 of Ts), 33.2 (–, 1 C, CH2CH2OTs), 49.6 (+, 1 C,
Ph3SiCH), 52.9 (+, 1 C, SiCHCH), 67.3 (–, 1 C, CH2OTs), 127.8
(+, 2 C, C-Ar), 128.1 (+, 6 C, C-Ar), 129.9 (+, 2 C, C-Ar), 130.1
(+, 3 C, C-Ar), 132.7 (q, 1 C, C-Ar), 133.8 (+, 1 C, C-Ar), 134.7
(q, 1 C, C-Ar), 135.9 (+, 6 C, C-Ar), 144.8 (q, 2 C, C-Ar) ppm. IR
C, C-Ar), 146.7 (+, 1 C, SiCH=CH) ppm. IR (NaCl): ν = 3068,
˜
3048, 2998, 2958, 2924, 2852, 1957, 1885, 1821, 1615, 1589, 1487,
1428, 1330, 1303, 1272, 1251, 1206, 1111, 1067, 1029, 994, 911,
794, 734, 699, 659, 636 cm–1. MS (DCP, 70 eV): m/z (%) = 315 (12)
[M+ – Me], 302 (14) [M+ – C2H4], 287 (6) [M+ – Me – C2H4], 224
(20), 197 (24) [SiMePh2], 180 (50), 130 (30), 105 (74) [SiPh], 104
(100), 91 (36), 77 (20) [Ph]. HRMS (EI): calcd. for C16H16BrSi [M –
Me]+ 315.0205; found 315.0206.
trans-4-Bromo-1-(triphenylsilyl)-1-butene (14d): According to the
procedure given for 14a, product 14d (288 mg, 98%) was obtained
from 12d (365 mg, 0.75 mmol) and LiBr (131 mg, 1.51 mmol) The
product was not further purified, but oxidized to 15d. 1H NMR
(200 MHz, CDCl3): δ = 2.75–2.87 (m, 2 H, CH2CH2Br), 3.47 (t, J
= 7.0 Hz, 2 H, CH2Br), 6.10 (dt, J = 18.4, 6.0 Hz, 1 H,
Ph3SiCH=CH), 6.34 (dt, J = 18.6, 1.1 Hz, 1 H, Ph3SiCH=CH),
7.31–7.69 (m, 15 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ
= 31.3 (–, 1 C, CH2Br), 39.7 (–, 1 C, CH2CH2Br), 127.5 (+,1 C,
Ph3SiCH=CH), 127.9 (+, 6 C, C-Ar), 129.6 (+, 3 C, C-Ar), 134.4
(q, 3 C, C-Ar), 135.9 (+, 6 C, C-Ar), 148.6 (+,1 C, Ph3SiCH=CH)
ppm.
(KBr): ν = 3067, 1700, 1596, 1574, 1485, 1428, 1359, 1304, 1263,
˜
1178, 1114, 987, 920, 901, 877, 819, 780, 748, 700, 659 cm–1. HRMS
(ESI): calcd. for C29H28O4SSi [M
523.1375.
+
Na]+ 523.1375; found
trans-4-Bromo-1-(triethylsilyl)-1-butene (14a): Following
a pro-
cedure by Negishi,[11] LiBr (155 mg, 1.79 mmol) was added to 12a
(304 mg, 0.89 mmol) in absolute acetone (20 mL) under an atmo-
sphere of nitrogen, and the mixture was heated at reflux for 10 h.
Then, the mixture was poured into water and extracted with petro-
leum ether (4ϫ). The combined organic phase was dried (MgSO4),
and the solvents were removed under vacuum. Product 14a
(194 mg, 87%) was obtained as a colorless liquid. 1H NMR
(200 MHz, CDCl3): δ = 0.48–0.68 (m, 6 H, SiCH2), 0.88–0.98 [m,
9 H, Si(CH2CH3)3], 2.62–2.74 (m, 2 H, CH2CH2Br), 3.42 (t, J =
7.1 Hz, 2 H, CH2CH2Br), 5.68 (dt, J = 18.7, 1.2 Hz, 1 H,
SiCH=CH), 5.98 (dt, J = 18.7, 6.0 Hz, 1 H, SiCH=CH) ppm. 13C
NMR (50 MHz, CDCl3): δ = 3.4 [-, 3 C, Si(CH2CH3)3], 7.3 [+, 3
C, Si(CH2CH3)3], 31.9 (–, 1 C, CH2Br), 39.9 (–, 1 C, CH2CH2Br),
129.9 (+, 1 C, Et3SiCH=CH), 143.9 (+, 1 C, Et3SiCH=CH) ppm.
trans-4-Bromo-1-(triethylsilyl)-1,2-epoxybutane (15a): According to
the procedure given for 8, product 15a (105 mg, 66%) was obtained
from 14a (153 mg, 0.61 mmol) as a colorless oil after flash
chromatography (PE/EA, 400:1). 1H NMR (200 MHz, CDCl3): δ
= 0.52–0.66 (m, 6 H, SiCH2CH3), 0.98 (t, J = 7.7 Hz, 9 H,
SiCH2CH3), 2.07–2.19 (m, 2 H, CH2CH2Br), 2.12 (d, J = 3.3 Hz,
1 H, Et3SiCHCH), 2.96 (ddd, J = 5.3, 5.3, 3.5 Hz, 1 H, Et3S-
iCHCH), 3.51 (t, J = 6.7 Hz, 2 H, CH2Br) ppm. 13C NMR
(50 MHz, CDCl3): δ = –1.8 (–, 3 C, SiCH2CH3), 7.2 (+, 3 C,
SiCH2CH3), 29.4 (–, 1 C, CH2Br), 37.4 (–, 1 C, CH2CH2Br), 50.2
(+, 1 C, Et3SiCHCH), 54.1 (+, 1 C, Et3SiCHCH) ppm. IR (NaCl):
IR (NaCl): ν = 2954, 2875, 2733, 1615, 1459, 1417, 1378, 1329,
˜
1303, 1273, 1238, 1205, 1126, 1015, 932, 784, 720, 636 cm–1. GC–
MS (70eV): m/z (%) = 221 (71), 219 (68) [M+ – Et], 193 (22), 191
(24), 167 (28), 165 (39), 163 (21), 151 (12), 141 (37) [M+ – C2H4 –
Br], 139 (34), 137 (32), 127 (22), 116 (18), 115 (100) [SiEt3], 113
(21), 111 (36), 109 (14), 101 (27), 87 (15), 83 (34), 81 (16), 55 (23).
HRMS (EI): calcd. for C8H16BrSi [M – Et]+ 219.0205; found
219.0206.
ν = 2955, 2912, 2876, 1459, 1416, 1293, 1264, 1236, 1209, 1016,
˜
974, 920, 869, 721 cm–1. MS (DCP, 70 eV): m/z (%) = 209 (40), 207
(34), 167 (65), 165 (71), 155 (14), 139 (100), 138 (10), 137 (88), 127
(21), 115 (79) [SiEt3], 111 (11), 109 (15), 103 (12), 99 (15), 87 (100)
[C4H11Si], 85 (16), 75 (34), 71 (24), 69 (24), 67 (12), 59 (86), 58
(21), 57 (31), 55 (31), 53 (19). HRMS (ESI): calcd. for C10H21BrOSi
[M + Na]+ 287.0443; found 287.0445.
trans-4-Bromo-1-(dimethylphenylsilyl)-1-butene (14b): According to
the procedure given for 14a, product 14b (127 mg, 86%) was ob-
tained from 12b (198 mg, 0.55 mmol) and LiBr (95 mg, 1.10 mmol)
trans-4-Bromo-1-(dimethylphenylsilyl)-1,2-epoxybutane (15b): Ac-
cording to the procedure given for 8, product 15b (120 mg, 91%)
was obtained from 14b (123 mg, 0.46 mmol) as a colorless oil. H
NMR (200 MHz, CDCl3): δ = 0.34 and 0.36 (each s, 3 H, CH3),
2.09–2.19 (m, 2 H, CH2CH2Br), 2.26 (d, J = 3.5 Hz, 1 H, PhMe2S-
1
as a colorless liquid. H NMR (200 MHz, CDCl3): δ = 0.35 (s, 6
1
H, SiCH3), 2.66–2.78 (m, 2 H, CH2CH2Br), 3.44 (t, J = 7.2 Hz, 2
H, CH2Br), 5.83–5.97 (m, 1 H, SiCH=CH), 6.08 (dt, J = 18.6,
5.6 Hz, 1 H, SiCH=CH), 7.34–7.40 (m, 3 H, Ar-H), 7.49–7.56 (m,
4680
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© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2009, 4674–4684

Synthesis of Functionalized Alkenes or Tetrahydrofurans
iCH), 2.93 (dt, J = 5.4, 3.4 Hz, 1 H, SiCHCH), 3.49 (t, J = 6.7 Hz,
2 H, CH2Br), 7.32–7.43 (m, 3 H, Ar-H), 7.50–7.61 (m, 2 H, Ar-H)
ppm. 13C NMR (50 MHz, CDCl3): δ = –5.2 and –5.1 (each +, 1 C,
(+, 1 C, PhSCHTMS), 71.1 (+, 1 C, CHOH), 126.0 (+, 1 C, C-Ar),
126.5 (+, 1 C, C-Ar), 128.8 (+, 2 C, C-Ar), 129.0 (+, 2 C, C-Ar),
130.1 (+, 2 C, C-Ar), 136.2 (q, 1 C, C-Ar), 138.1 (q, 1 C, C-Ar)
SiCH3), 29.3 (–, 1 C, CH2Br), 37.0 (–, 1 C, CH2CH2Br), 51.2 (+, ppm. IR (NaCl): ν = 3473, 3058, 3018, 2954, 2899, 1943, 1583,
˜
1 C, PhMe2SiCH), 54.6 (+, 1 C, SiCHCH), 128.0 (+, 2 C, C-Ar),
1479, 1439, 1378, 1249, 1216, 1091, 1067, 1043, 1025, 1000, 841,
129.6 (+, 1 C, C-Ar), 133.9 (+, 2 C, C-Ar), 135.8 (q, 1 C, C-Ar)
740, 691, 665, 618 cm–1. MS (DCP) (70 eV) m/z (%) = 362 (1) [M+],
ppm. IR (NaCl): ν = 3070, 3049, 2961, 1728, 1589, 1488, 1428, 253 [M+ – SPh], 163 (100) [M+ – SPh – TMSOH], 149 (14), 123
˜
1291, 1250, 1209, 1116, 999, 923, 834, 787, 735, 701, 635 cm–1. GC–
MS (70eV): m/z (%) = 256 (8) [M+ – C2H4], 209 (23), 191 (35), 177
(14), 135 (100) [SiMe2Ph], 131 (43), 117 (19), 105 (18), 91 (16), 75
(27) [C2H7OSi]. HRMS (ESI): calcd. for C12H17BrOSi [M + Na]+
307.0130; found 307.0136.
(23), 109 (10) [SPh], 73 (50) [TMS]. HRMS (ESI): calcd. for
C19H26OS2Si [M + Na]+ 385.1092; found 385.1093.
Synthesis of trans-5-(Tosyloxy)-1-(trimethylsilyl)-3-(trimethylsilyl-
oxy)-1-pentene (18) by Reaction of cis-Epoxysilane 8a with Lithiated
Phenylthio(trimethylsilyl)methane (17): BuLi (2.45  in hexane,
0.90 mL, 2.2 mmol) was added dropwise to protonated 17 (137 mg,
0.7 mmol) in absolute THF (4 mL) at 0 °C under an atmosphere
of nitrogen. Stirring was continued for 20 min. Then, the yellow
solution of 17 was added dropwise to 8a (111 mg, 0.35 mmol) in
absolute THF (4 mL) at 0 °C. After 15 min at 0 °C the reaction
mixture was stirred at room temperature overnight. Water was
added, the phases separated, and the aqueous phase was extracted
with diethyl ether (3ϫ). The combined organic phase was dried
(MgSO4) and the solvents were evaporated under vacuum. The
product was isolated by flash chromatography as a colorless oil.
trans-4-Bromo-1-(methyldiphenylsilyl)-1,2-epoxybutane (15c): Ac-
cording to the procedure given for 8, product 15c (211 mg, 84%)
was obtained from 14c (239 mg, 0.72 mmol) as a colorless oil after
flash chromatography (PE/EA, 30:1). 1H NMR (200 MHz,
CDCl3): δ = 0.61 (s, 3 H, CH3), 2.19 (dt, J = 6.6, 5.6 Hz, 2 H,
CH2CH2Br), 2.54 (d, J = 3.5 Hz, 1 H, Ph2MeSiCH), 2.94 (dt, J =
5.4, 3.4 Hz, 1 H, SiCHCH), 3.49 (t, J = 6.7 Hz, CH2Br), 7.33–7.45
(m, 6 H, Ar-H), 7.56–7.64 (m, 4 H, Ar-H) ppm. 13C NMR
(50 MHz, CDCl3): δ = –6.4 (+, 1 C, CH3), 29.1 (–, 1 C, CH2Br),
36.9 (–,1 C, CH2CH2Br), 50.3 (+, 1 C, Ph2MeSiCH), 54.7 (+, 1 C,
SiCHCH), 128.0 (+, 4 C, C-Ar), 129.9 (+, 2 C, C-Ar), 133.7 (q, 1
C, C-Ar), 134.0 (q, 1 C, C-Ar), 134.8 (+, 2 C, C-Ar), 134.9 (+, 2
1
Yield: 66 mg (47%). H NMR (200 MHz, CDCl3): δ = 0.03, 0.04
(each s, 9 H, SiCH3), 1.66–1.84 (m, 2 H, CH2CH2OTs), 2.44 (s, 3
H, CH3 of Ts), 3.99–4.21 (m, 3 H, CHOTMS, CH2OTs), 5.72 (d,
J = 18.7 Hz, 1 H, SiCH=CH), 5.87 (dd, J = 18.7, 5.0 Hz, 1 H,
SiCH=CH), 7.34 (d, J = 7.9 Hz, 2 H, Ar-H), 7.79 (d, J = 8.3 Hz,
2 H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ = –1.5, 0.1 (each
+, 3 C, SiCH3), 21.6 (+, 1 C, CH3of Ts), 36.6 (–, 1 C, CH2CH2OTs),
67.2 (–, 1 C, CH2OTs), 71.4 (+, 1 C, CHOTMS), 127.9 (+, 2 C, C-
Ar), 129.8 (+, 2 C, C-Ar), 130.1 (+, 1 C, SiCH=CH), 133.2 (q, 1
C, C-Ar), 144.7 (q, 1 C, C-Ar), 147.4 (+, 1 C, SiCH=CH) ppm. IR
C, C-Ar) ppm. IR (NaCl): ν = 3069, 3048, 2999, 2965, 1589, 1487,
˜
1428, 1290, 1253, 1209, 1115, 998, 922, 869, 791, 730, 700,
656 cm–1. GC–MS (70eV): m/z (%) = 318 (16) [M+ – C2H4], 253
(32), 197 (44) [SiMePh2], 181 (66), 175 (33), 165 (32), 131 (100).
HRMS (ESI): calcd. for C17H19BrOSi [M + NH4]+ 364.0732; found
364.0730.
trans-4-Bromo-1-(triphenylsilyl)-1,2-epoxybutane (15d): According
to the procedure given for 8, product 15d (120 mg, 59%) was ob-
tained from 14d (200 mg,0.50 mmol) as a colorless solid after flash
(NaCl): ν = 3032, 2956, 2899, 1922, 1621, 1599, 1496, 1366, 1307,
˜
1250, 1189, 1177, 1097, 1021, 994, 922, 839, 760, 690, 664, 637,
609 cm–1. GC–MS (70 eV): m/z (%) = 385 (6) [M+ – Me], 317 (100),
303 (10), 155 (11), 141 (16), 127 (13), 103 (24), 91 (8), 73 (20),
67 (27). HRMS (ESI): calcd. for C15H24O4SSi [M + Na – TMS]+
351.1062; found 351.1068.
1
chromatography (PE/EA, 60:1). M.p. 93 °C. H NMR (200 MHz,
CDCl3): δ = 2.23 (dt, J = 6.8, 5.4 Hz, 2 H, CH2CH2Br), 2.80 (d, J
= 3.3 Hz, 1 H, CHSiPh3), 2.93 (dt, J = 5.4, 3.3 Hz, 1 H, SiCHCH),
3.47 (t, J = 6.8 Hz, 2 H, CH2Br), 7.34–7.62 (m, 15 H, Ar-H) ppm.
13C NMR (50 MHz, CDCl3): δ = 28.9 (–, 1 C, CH2Br), 37.0 (–, 1
C, CH2CH2Br), 49.5 (+, CHSiPh3), 54.9 (+, 1 C, SiCHCH), 128.1
(+, 2 C, C-Ar), 130.1 (+, 1 C, C-Ar), 131.9 (q, 1 C, C-Ar), 135.9
Synthesis of 1,4-Bis(phenylthio)-2-(dimethylphenylsilyloxy)butane
(19) by Reaction of trans-Silylepoxide 13b with Magnesium Chloride
Thiophenoxide: Methylmagnesium chloride (1  in ether, 0.06 mL,
0.17 mmol) was added dropwise to thiophenol (0.02 mL,
0.17 mmol) in absolute THF (0.3 mL) at –78 °C under an atmo-
sphere of nitrogen. After 10 min, 13b (65 mg, 0.17 mmol) in abso-
lute THF (1 mL) was added dropwise to this solution. The mixture
was warmed to room temperature and saturated aqueous NH4Cl
(2 mL) was added. The phases were separated, and the aqueous
phase was extracted with diethyl ether (2ϫ). The combined organic
phase was washed with NaOH (5%) and dried (MgSO4). The prod-
uct was purified by flash chromatography (PE/EA, 10:1) to give a
(+, 2 C, C-Ar) ppm. IR (KBr): ν = 3066, 2919, 1587, 1484, 1427,
˜
1211, 1185, 1113, 997, 870, 811, 789, 741, 699 cm–1. HRMS (ESI):
calcd. for C22H21BrOSi [M + Na]+ 431.0443; found 431.0444.
Synthesis of 1,4-Bis(phenylthio)-1-(trimethylsilyl)butan-2-ol (16) by
Reaction of cis-Silylepoxide 8a with Lithium Thiophenoxide: On the
basis of a literature procedure,[30] BuLi (2.45  in hexane, 0.26 mL,
0.33 mmol) was added dropwise to thiophenol (0.06 mL, 0.6 mmol)
in absolute THF (1 mL) at –78 °C under an atmosphere of nitro-
gen. After 10 min at –78 °C, 8a (78 mg, 0.25 mmol) in absolute
THF (1 mL) was added dropwise. The reaction mixture was al-
lowed to reach room temperature within 2 h. Then, saturated aque-
ous NH4Cl (3 mL) and water (4 mL) were added, the phases were
separated, and the aqueous phase was extracted with diethyl ether
(2ϫ). The combined organic phase was washed with NaOH (5%,
10 mL), dried (MgSO4), and the solvents removed in vacuo. After
flash chromatography (PE/EA, 10:1), a colorless oil was isolated.
Yield: 65 mg (72%). 1H NMR (200 MHz, CDCl3): δ = 0.18 (s, 9
H, SiCH3), 1.57–1.92 (m, 2 H, CH2CH2SPh), 2.11 (br. s, 1 H, OH),
1
colorless oil. Yield: 40 mg (55%). H NMR (200 MHz, CDCl3): δ
= 0.43 (s, 6 H, SiCH3), 1.53–1.67, 1.72–1.89 (each m, 1 H,
CH2CH2SPh), 2.71–3.10 (m, 4 H, CH2SPh), 3.94–4.07 (m, 1 H,
CHOSi), 7.12–7.64 (m, 15 H, Ar-H) ppm. 13C NMR (50 MHz,
CDCl3): δ = –3.0, –2.6 (each +, 1 C, SiCH3), 30.5 (–, 1 C,
CH2CH2SPh), 35.1 (–,
1
C, CH2SPh), 44.3 (–,
1
C,
PhSCH2CHOSi), 72.3 (+, 1 C, CHOSi), 125.9 (+, 1 C, C-Ar), 126.4
(+, 1 C, C-Ar), 127.9 (+, 2 C, C-Ar), 128.9 (+, 2 C, C-Ar), 129.0
(+, 2 C, C-Ar), 129.2 (+, 2 C, C-Ar), 129.5 (+, 1 C, C-Ar), 129.9
2.57 (d, J = 3.5 Hz, 1 H, PhSCHTMS), 2.75–3.04 (m, 2 H, (+, 2 C, C-Ar), 134.1 (+, 2 C, C-Ar), 136.2 (q, 1 C, C-Ar), 136.8
CH2SPh), 4.03 (dt, J = 9.0, 3.7 Hz, 1 H, CHOH), 7.12–7.41 (m, 10
(q, 1 C, C-Ar), 137.5 (q, 1 C, C-Ar) ppm. IR (NaCl): ν = 3069,
2956, 1583, 1480, 1438, 1427, 1251, 1113, 1026, 823, 788, 738,
˜
H, Ar-H) ppm. 13C NMR (50 MHz, CDCl3): δ = –1.7 (+, 3 C,
SiCH3), 30.7 (–, 1 C, CH2CH2SPh), 36.4 (–, 1 C, CH2SPh), 43.6 692 cm–1. MS (DCP, 70 eV): m/z (%) = 281 (33), 229 (68), 218 (47),
Eur. J. Org. Chem. 2009, 4674–4684
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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4681

J. Lange, E. Schaumann
180 (39), 163 (95), 155 (21), 149 (75), 137 (91), 135 (100) [SiMe2Ph], ether (1ϫ). The combined organic phase was dried (MgSO4), and
FULL PAPER
124 (64), 123 (98) [CH2SPh], 110 (69), 109 (84) [SPh], 91 (74), 77
(39) [Ph], 65 (50). LRMS (ESI): calcd. for C24H28OS2Si [M +
Na]+ 447.1; found 447.1.
the solvents were evaporated under vacuum. The product was iso-
lated by flash chromatography (PE; PE/EA, 400:1; 200:1; 100:1).
The following products were obtained:
Synthesis of 5-(Tosyloxy)-2-pentenenitrile (20) and 3-Hydroxy-5-
(tosyloxy)pentanenitrile (21) by Reaction of trans-Silylepoxide 13b
with Diethylaluminium Cyanide: Adopting a literature procedure,[31]
diethylaluminium cyanide (1  in toluene, 0.31 mL, 0.31 mmol) was
added dropwise to 13b (116 mg, 0.31 mmol) in toluene (3 mL) at
–78 °C under an atmosphere of nitrogen. Stirring was continued
for 3 h, the mixture was then warmed to room temperature and
heated at reflux for 6 h. More diethylaluminium cyanide in THF
(0.62 mL, 0.62 mmol) was added and the stirring continued at
room temperature for 2 d. A mixture of saturated aqueous sodium
potassium tartrate and EA (1:1, 4 mL) was added, and the phases
were separated. The aqueous phase was extracted with EA and the
combined organic phase was dried (Na2SO4). Flash chromatog-
raphy gave products 20 and 21. Data for 20 (E:Z, 4.5:1): Yellowish
cis-1,5,5-Tris(thiomethyl)-5-trimethylsilyl-1-pentene (25): From 8a
(96 mg, 0.31 mmol) or 8b (61 mg, 0.16 mmol). Yellow oil. Yield:
14 mg (16%) from 8a, 23 mg (51%) from 8b. H NMR (200 MHz,
1
CDCl3):
δ = 0.22 (s, 9 H, SiCH3), 1.77–1.88 (m, 2 H,
=CHCH2CH2), 2.05 (s, 6 H, SCH3), 2.27 (s, 3 H, SCH3), 2.29–2.40
(m, 2 H, =CHCH2), 5.49 (dt, J = 9.3, 7.2 Hz, 1 H, =CHCH2), 5.90
(dt, J = 9.3, 1.2 Hz, 1 H, MeSCH=CH) ppm. 13C NMR (50 MHz,
CDCl3): δ = –1.0 (+, 3 C, SiCH3), 11.2, 7.0 (each +, 1 C, SCH3),
26.7 (–, 1 C, C=CHCH2), 36.6 (–, 1 C, =CHCH2CH2), 47.1 [q,
1 C, C(SMe)TMS], 127.6 (+, 1 C, MeSCH=CH), 127.6 (+, 1 C,
MeSCH=CH) ppm. IR (NaCl): ν = 2955, 2918, 1734, 1608, 1435,
˜
1314, 1248, 1077, 962, 840, 757, 692, 625 cm–1. GC–MS (70 eV):
m/z (%) = 265 (18) [M+], 233 (100) [M+ – SMe], 217 (23), 193 (18)
[CH2C(SMe)2TMS], 185 (18), 159 (27), 145 (56), 113 (21), 87 (60)
[C4H7S], 73 (30) [TMS], 45 (33) [CHS]. HRMS (EI): calcd. for
C10H21S2Si [M – SMe]+ 233.0854; found 233.0852.
1
oil. Yield: 45 mg (58%). H NMR (200 MHz, CDCl3): δ = 2.45 (s,
3 H, CH3 of Ts), 2.50–2.61 (m, 2 H, E-CH2CH2OTs), 2.68–2.79
(m, 2 H, Z-CH2CH2OTs), 4.11 (t, J = 6.0 Hz, 2 H, CH2OTs), 5.36
(dt, J = 16.4, 1.7 Hz, 1 H, E-NC-CH=CH), 6.45 (dt, J = 11.1,
7.3 Hz, 1 H, Z-NC-CH=CH), 6.49 (dt, J = 16.4, 6.9 Hz, 1 H, E-
NC-CH=CH), 7.32–7.40 (m, 2 H, Ar-H), 7.73–7.80 (m, 2 H, Ar-
H) ppm. 13C NMR (50 MHz, CDCl3): δ = 21.6 (+, 1 C, CH3 of
Ts), 31.1 (–, 1 C, Z-CH2CH2OTs), 32.4 (–, 1 C, E-CH2CH2OTs),
67.0 (–, 1 C, E-CH2OTs), 67.5 (–, 1 C, Z-CH2OTs), 102.7 (+, 1 C,
Z-NC-CH=CH), 103.0 (+, 1 C, E-NC-CH=CH), 116.6 (q, 1 C,
CN), 127.8 (+, 2 C, C-Ar), 129.9 (+, 2 C, C-Ar), 132.4 (q, 1 C, C-
Ar), 145.3 (q, 1 C, C-Ar), 148.6 (+, 1 C, Z-NC-CH=CH), 149.3
2-(Methylthio)-2-(trimethylsilyl)-5-(1-methylthio-1-triethylsilyl)-
methyl-tetrahydrofuran (28a): From 13a (220 mg, 0.62 mmol) or
15a (97 mg, 0.37 mmol). Colorless oil. Yield: 108 mg (48%) from
13a, 81 mg (60%) from 15a. 1H NMR (400 MHz): δ = 0.14 (s, 9
H, SiCH3), 0.61–0.70 (m, 6 H, SiCH2CH3), 0.98 (t, J = 7.9 Hz, 9
H, SiCH2CH3), 1.74–1.92 (m, 2 H, CH2), 2.04 (s, 3 H, SCH3), 2.20–
2.25 (m, 2 H, CH2), 2.22 (s, 3 H, CHSCH3), 2.31 [d, J = 4.5 Hz, 1
H, CH(SMe)], 4.47 (ddd, J = 8.9, 6.3, 4.5 Hz, 1 H, CH-THF ring)
ppm. 13C NMR (50 MHz, CDCl3): δ = –2.6 (+, 3 C, SiCH3), 3.3
(–, 3 C, SiCH2CH3), 7.7 (+, 3 C, SiCH2CH3), 12.8 (+, 1 C, SCH3),
20.8 (+, 1 C, CHSCH3), 29.4 (–, 1 C, CH2), 36.2 (+, 1 C, CHSCH3),
36.4 (–, 1 C, CH2), 81.2 (+, 1 C, CH-THF ring), 85.3 (q, 1 C) ppm.
(+, 1 C, E-NC-CH=CH) ppm. IR (NaCl): ν = 2225, 1598, 1360,
˜
1177, 1097, 957, 817, 757, 665 cm–1. MS (DCP, 70 eV): m/z (%) =
251 (17) [M+], 187 (18) [M+ – SO2], 172 (16) [M+ – SO2Me], 156
(15) [M+ – MeOSO2], 155 (97) [Ts], 137 (43), 91 (100) [Bn], 65 (45)
[C5H5]. HRMS (EI): calcd. for C12H13NO3S [M]+ 251.0616; found
IR (NaCl): ν = 2954, 2917, 2875, 1458, 1416, 1378, 1311, 1247,
˜
1089, 1019, 953, 839, 732, 624 cm–1. GC–MS (70eV): m/z (%) =
301 (60) [M+ – MeSO], 287 (29) [M+ – Me2S – Me], 273 (32) [M+
–
251.0617. HRMS (ESI): calcd. for C12H14NO3S [M
+
H]+
Me2S – Et], 269 (26), 243 (20), 215 (18), 185 (29), 176 (42)
[C8H20SSi], 153 (44), 147 (64), 141 (80), 133 (30), 119 (34), 115
(100) [SiEt3], 105 (27), 87 (90), 73 (87) [TMS], 59 (60). HRMS
(ESI): calcd. for C16H36OS2Si2 [M + Na]+ 387.1644; found
387.1640.
252.0694; found 252.0698. Data for 21: Yellow oil. Yield: 10 mg
(12%). 1H NMR (200 MHz, CDCl3): δ = 1.74–2.07 (m, 2 H,
CH2CH2OTs), 2.46 (s, 3 H, CH3 of Ts), 2.53 (d, J = 3.7 Hz, 1 H,
NC-CH2), 2.56 (d, J = 2.8 Hz, 1 H, NC-CH2), 2.65 (br. s, 1 H,
OH), 4.01–4.20 (m, 2 H, CH2OTs), 4.23–7.37 (m, 1 H, CHOH),
7.37 (d, J = 7.9 Hz, 2 H, Ar-H), 7.79 (d, J = 8.3 Hz, 2 H, Ar-H)
ppm. 13C NMR (50 MHz, CDCl3): δ = 21.7 (+, 1 C, CH3 of Ts),
26.2 (–, 1 C, NC-CH2), 35.3 (–, 1 C, CH2CH2OTs), 63.8 (+, 1 C,
CHOH), 66.5 (–, 1 C, CH2OTs), 117.1 (q, 1 C, CN), 127.9 (+, 2 C,
C-Ar), 130.0 (+, 2 C, C-Ar), 132.5 (q, 1 C, C-Ar), 145.3 (q, 1 C,
2-(Methylthio)-2-(trimethylsilyl)-5-(1-methylthio-1-dimethylphenyl-
silyl)methyl-tetrahydrofuran (28b): From 13b (141 mg, 0.37 mmol)
or 15b (113 mg, 0.40 mmol). Colorless oil. Yield: 58 mg (41%) from
1
13b, 105 mg (68%) from 15b. H NMR (400 MHz): δ = 0.12 (s, 9
H, SiCH3), 0.40 and 0.42 [each s, 3 H, Si(CH3)2Ph], 1.64–1.74 (m,
1 H, CHCH2CH2), 1.83 (ddd, J = 13.0, 8.9, 6.0 Hz, 1 H,
CHCH2 CH2 ), 1.96 (s, 3 H, SCH3 ), 1.97–2.02 (m, 1 H,
CHCH2CH2), 2.16–2.19 (m, 1 H, CHCH2CH2), 2.34 (d, J =
4.7 Hz, 1 H, CHSMe), 4.40 (ddd, J = 8.5, 6.7, 4.8 Hz, 1 H, CH-
THF ring), 7.33–7.38 (m, 3 H, Ar-H), 7.56–7.61 (m, 2 H, Ar-H)
ppm. 13C NMR (100 MHz): δ = –3.4 and –3.2 [each +, 1 C,
Si(CH3)2Ph], –2.6 (+, 3 C, SiCH3), 12.7 (+, 1 C, SCH3), 20.2 [+, 1
C, CH(SCH3 )], 29.2 (–, 1 C, CHCH2CH2 ), 36.2 (–, 1 C,
CHCH2CH2), 38.8 [+, 1 C, CH(SCH3)], 81.1 (+, 1 C, CH-THF
ring), 85.5 (q, 1 C, C-THF ring), 127.7 (+, 2 C, C-Ar), 129.2 (+, 1
C, C-Ar), 134.0 (+, 2 C, C-Ar), 137.2 (q, 1 C, C-Ar) ppm. IR
C-Ar) ppm. IR (NaCl): ν = 3483, 2927, 2252, 1598, 1355, 1174,
˜
1097, 1019, 933, 817, 768, 665 cm–1. MS (DCP, 70 eV): m/z (%) =
269 (33) [M+], 205 (72) [M+ – SO2], 173 (82), 172 (82), 155 (84)
[Ts], 98 (40) [M+ – OTs], 91 (100) [Bn], 65 (84) [C5H5]. HRMS
(ESI): calcd. for C12H15NO4S [M + Na + MeCN]+ 333.0885; found
333.0887.
General Procedure for the Reaction of Epoxysilanes 8, 13, and 15
with Lithiated Bis(methylthio)trimethylsilylmethane (23): BuLi
(2.45  in hexane, 1.9 mL, 2.2 mmol) was added dropwise to 23
(360 mg, 2 mmol) in absolute THF (2 mL) at – 78 °C under an
atmosphere of nitrogen. Stirring was continued for 1 h at –78 °C,
then at 0 °C for 30 min and finally at room temperature for 15 min.
Then, the solution of the epoxide (1 mmol) in absolute THF (3 mL)
was added slowly at 0 °C. The reaction mixture was stirred at room
temperature overnight. The resulting mixture was poured into a
mixture of saturated aqueous NH4Cl/water/diethyl ether (1:1:1), the
phases separated, and the aqueous phase extracted with diethyl
(NaCl): ν = 3069, 3049, 2957, 2920, 1600, 1487, 1427, 1362, 1312,
˜
1248, 1186, 1115, 1024, 956, 838, 736, 701, 648, 623 cm–1. GC–MS
(70eV): m/z (%) = 321 (15) [M+ – MeSO], 293 (13), 209 (16), 196
(14) [C10H16SSi], 153 (20), 147 (35), 141 (49), 135 (100) [SiMe2Ph],
105 (25) [SiPh], 87 (24), 73 (85) [TMS]. HRMS (ESI): calcd. for
C18H32OS2Si2 [M + Na]+ 407.1331; found 407.1338.
4682
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© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2009, 4674–4684

Synthesis of Functionalized Alkenes or Tetrahydrofurans
2-(Methylthio)-2-(trimethylsilyl)-5-(1-methylthio-1-diphenylmethyl-
gen. Stirring was continued for 1 h at –78 °C, then at 0 °C for
silyl)methyl-tetrahydrofuran (28c): From 13c (91 mg, 0.21 mmol) or
30 min, and finally at room temperature for 15 min. Then, a solu-
from 15c (200 mg, 0.58 mmol). Yield: 37 mg (40 %) from 13c, tion of 13c or 13d (1 mmol) in absolute THF (5 mL) was added
120 mg (46 %) from 15c. Slightly yellowish oil. 1H NMR
(400 MHz): δ = 0.11 (s, 9 H, SiCH3), 0.68 (s, 3 H, SiCH3Ph2), 1.66–
1.74 (m, 1 H, CHCH2CH2), 1.81 (ddd, J = 12.7, 8.8, 5.8 Hz, 1 H,
CHCH2 CH2 ), 1.90 (s, 3 H, SCH3 ), 1.90–1.96 (m, 1 H,
CHCH2CH2), 2.18 [s, 3 H, CH(SCH3)], 2.21–2.25 (m, 1 H,
HCH2CH2), 2.80 [d, J = 4.5 Hz, 1 H, CH(SMe)], 4.48 (ddd, J =
8.5, 6.6, 4.4 Hz, 1 H, CH-THF ring), 7.34–7.69 (m, 10 H, Ar-H)
ppm. 13C NMR (100 MHz): δ = –4.4 (+, 1 C, SiCH3Ph2), –2.7 [+,
3 C, Si(CH3)3], 12.6 (+, 1 C, SCH3), 20.5 [+, 1 C, CH(SCH3)], 29.1
(–, 1 C, CHCH2CH2), 36.2 (–, 1 C, CHCH2CH2), 37.3 [+, 1 C,
CH(SCH3)], 80.9 (+, 1 C, CH-THF ring), 85.4 (q, 1 C, C-THF
ring), 127.7 (+, 2 C, C-Ar), 127.8 (+, 2 C, C-Ar), 129.5 (+, 2 C, C-
Ar), 134.6 (+, 2 C, C-Ar), 135.0 (+, 2 C, C-Ar), 135.1 (q, 1 C, C-
slowly at –78 °C. The reaction mixture was warmed to –20 °C for
1.5 h and stirred at room temperature overnight. Workup was car-
ried out as given above for the synthesis of 26. Yield: 35 mg (64%)
from 13d (89 mg, 0.18 mmol), 276 mg (57 %) from 13c (707 mg,
1.61 mmol). Colorless oil. The spectra agree with the data in ref.[32]
2-(Trimethylsilyl)-5-(1-methylsulfonyl-1-triethylsilyl)methyl-4,5-di-
hydrofuran (31): The oxidation procedure was based on a literature
method.[33] Compound 28a (169 mg, 0.46 mmol) in CH2Cl2
(10 mL) was diluted with acetone (2 mL) and saturated aqueous
NaHCO3 (35 mL). At 0 °C, Oxone (5.697 g, 9.27 mmol) in water
(20 mL) was carefully added to the two-phase mixture. After an-
other 30 min at 0 °C the mixture was stirred overnight at room
temperature The phases were separated, and the aqueous phase
was extracted with CH2Cl2 (2ϫ). The combined organic phase was
dried (Na2SO4), and the solvents were removed in vacuo. The prod-
uct was purified by flash chromatography (PE/EA, 5:1). Yield:
66 mg (41%). Colorless solid. M.p. 44–45 °C. 1H NMR (400 MHz):
δ = 0.12 (s, 9 H, SiCH3), 0.74–0.97 (m, 6 H, SiCH2CH3), 1.02 (t, J
= 7.7 Hz, 9 H, SiCH2CH3), 2.58 (ddd, J = 15.7, 11.1, 2.8 Hz, 1 H,
CH2CH=C), 2.95 (s, 3 H, SO2CH3), 3.21 (ddd, J = 15.7, 12.0,
2.2 Hz, 1 H, CH2CH=C), 3.41 (d, J = 3.3 Hz, 1 H, Et3SiCH), 4.81
(dt, J = 11.5, 3.3 Hz, 1 H, Et3SiCHCH), 5.25 (t, J = 2.4 Hz, 1 H,
CH=C) ppm. 13C NMR (100 MHz): δ = –2.3 (+, 3 C, SiCH3), 3.8
(–, 3 C, SiCH2CH3), 7.4 (+, 3 C, SiCH2CH3), 33.3 (–, 1 C,
CH2CH=C), 45.8 (+, 1 C, SO2CH3), 56.6 (+, 1 C, Et3SiCH), 80.0
(+, 1 C, Et3SiCHCH), 113.2 (+, 1 C, CH=C), 161.5 (q, 1 C, CH=C)
Ar), 135.6 (q, 1 C, C-Ar) ppm. IR (NaCl): ν = 3069, 3049, 2958,
˜
2920, 1955, 1599, 1488, 1428, 1352, 1313, 1249, 1194, 1112, 1028,
956, 890, 840, 724, 698, 628 cm–1. GC–MS (70eV): m/z (%) = 383
(79) [M+ – MeSO], 355 (42), 321 (28), 305 (25), 273 (34), 271 (45),
258 (80), 257 (57) [C15H17SSi], 241 (26), 221 (27), 209 (58), 197 (38)
[SiMePh2], 185 (100), 179 (60), 167 (26), 153 (39), 141 (81), 105
(34) [SiPh], 87 (93), 73 (89) [TMS]. HRMS (ESI): calcd. for
C23H34OS2Si2 [M + Na]+ 469.1487; found 469.1491.
2-(Methylthio)-2-(trimethylsilyl)-5-(1-methylthio-1-triphenylsilyl)-
methyl-tetrahydrofura (28d): From 13d (213 mg, 0.43 mmol) or
from 15d (95 mg, 0.23 mmol). Yield: 47 mg (21%) from 13d, 41 mg
1
(35%) from 15d. Colorless oil. H NMR (400 MHz): δ = 0.12 (s, 9
H, SiCH3), 1.76–1.80 (m, 2 H, CH2), 1.87 (s, 3 H, SCH3), 2.09 (dd,
J = 14.5, 7.4 Hz, 2 H, CH2), 2.26 [s, 3 H, CH(SCH3)], 3.19 [d, J =
3.5 Hz, 1 H, CH(SMe)], 4.71 (ddd, J = 7.3, 7.3, 3.5 Hz, 1 H, CH-
THF ring), 7.33–7.48 (m, 15 H, Ar-H) ppm. 13C NMR (50 MHz,
CDCl3): δ = –2.6 (+, 3 C, SiCH3), 12.4 (+, 1 C, SCH3), 21.2 [+, 1
C, CH(SCH3)], 28.9 (–, 1 C, CH2), 36.3 (–, 1 C, CH2), 36.8 [+, 1
C, CH(SCH3)], 80.7 (+, 1 C, CH-THF ring), 85.3 (q, 1 C, C-THF
ring), 127.8 (+, 6 C, C-Ar), 129.7 (+, 3 C, C-Ar), 133.5 (q, 3 C, C-
ppm. IR (NaCl): ν = 3045, 2954, 2885, 1733, 1597, 1463, 1416,
˜
1364, 1316, 1292, 1245, 1204, 1127, 1076, 1025, 1005, 972, 948,
884, 838, 803, 750, 734, 720, 706, 632, 601. MS (DCP, 70 eV): m/z
(%) = 348 (3) [M+], 319 (27) [M+ – Et], 267 (19), 165 (13), 147 (33),
119 (23), 115 (22) [SiEt3], 97 (15), 87 (36), 85 (11), 83 (18), 75 (31)
[C2H7OSi], 73 (100) [TMS], 59 (36), 58 (11), 57 (10), 55 (10).
HRMS (ESI): calcd. for C15H32O3SSi2 [M + H]+ 349.1689; found
349.1686.
Ar), 136.0 (+, 6 C, C-Ar) ppm. IR (NaCl): ν = 3069, 3049, 2998,
˜
2956, 2919, 1960, 1893, 1824, 1679, 1589, 1567, 1485, 1428, 1311,
1248, 1218, 1190, 1158, 1110, 1027, 956, 840, 755, 700, 625 cm–1.
GC–MS (70eV): m/z (%) = 445 (5) [M+ – MeSO], 320 (10)
[C20H20SSi], 271 (7), 259 (100) [SiPh3], 181 (9), 141 (11), 87 (8), 73
(29) [TMS], 45 (11). HRMS (ESI): calcd. for C28H36OS2Si2 [M +
Na]+ 531.1644; found 531.1652.
Acknowledgments
We thank the Deutsche Forschungsgemeinschaft (Scha 231/11-1)
and the Fonds der Chemischen Industrie, Frankfurt, for generous
support of our work. Helpful suggestions on the mechanism of
formation of 25 and 28 by Prof. K. Takeda, Hiroshima University,
Japan, are gratefully acknowledged.
trans-5,5-Bis(methylthio)-5-(trimethylsilyl)-1-(phenyl)-1-pentene
(35): Was isolated along with 28d. Yield: 32 mg (24%) from 13d,
1
21 mg (29%) from 15d. Yellow oil. H NMR (200 MHz, CDCl3):
δ = 0.23 (s, 9 H, SiCH3), 1.88–1.99 [m, 2 H, CH2C(SMe)2], 2.07 (s,
6 H, SCH3), 2.35–2.49 (m, 2 H, PhCH=CHCH2), 6.19 (dt, J =
15.8, 6.6 Hz, 1 H, PhCH=CHCH2), 6.42 (dt, J = 15.8, 1.2 Hz, 1 H,
PhCH=CH), 7.17–7.38 (m, 5 H, Ar-H) ppm. 13C NMR (50 MHz,
CDCl3): δ = –0.9 (+, 3 C, SiCH3), 11.3 (+, 2 C, SCH3), 30.3 (–, 1
C, PhCH=CHCH2), 37.5 [-, 1 C, CH2C(SMe)2], 47.1 [q, 1 C,
C(SMe)2], 125.9 (+, 2 C, C-Ar), 127.0 (+, 1 C, C-Ar), 128.5 (+, 2
C, C-Ar), 129.9 (+, 1 C, C-olefin), 130.2 (+, 1 C, C-olefin), 137.5
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Received: April 22, 2009
Published Online: August 7, 2009
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