(E)-1-(Phenylsulfonyl)-4-(trimethylsilyl)-1-butene: An Advantageous Synthetic Equivalent for the 1-(1,3-Butadienyl) Anion and the 1,1-(1,3-Butadienyl) Dianion

Article abstract of DOI:10.1021/jo970546c

The (E)-1-(arylsulfonyl)-4-(trimethylsilyl)-1-butenes 9, 25, and 26 are prepared by CuCl₂-promoted and by photolytic additions of their precursor 1-arylsulfonyl chlorides and bromides to 4-(trimethylsilyl)-1-butene (14) and then dehydrohalogenation of the resulting 1-(arylsulfonyl)-2-halo-4-(trimethylsilyl)butanes 15a, 15b, 23a, and 23b with KOH, LDA, or n-BuLi. Silylbutene 14 is obtained from reaction of [(trimethylsilyl)methyl]magnesium chloride (16, X = Cl) and allyl bromide (17) and better by protiodesilylations of (E)- and (Z)-1,4-bis(trimethylsilyl)-2-butenes (20) with sulfuric or trifluoroacetic acids. (Arylsulfonyl)(trimethylsilyl)-1-butenes 9, 25, and 26 are converted efficiently by LDA or n-BuLi at -78°C to 1-(arylsulfonyl)-1-lithio-4-(trimethylsilyl)-1-butenes 10, 27a, and 27b, respectively. Reactions of 27a and 27b with deuterium oxide yield (E)-1-(4-chlorophenylsulfonyl)-1-deuterio-4-(trimethylsilyl)-1-butene (28a, 83%) and (E)-1-deuterio-1-(4-methylphenylsulfonyl)-4-(trimethylsilyl)-1-butene (28b, 89%), respectively. 1-Lithio derivatives 10, 27a, and 27b undergo benzylations by benzyl bromide in THF/HMPA with retention of the positions of their olefinic double bonds to give the (E)-2-(arylsulfonyl)-1-phenyl-5-(trimethylsilyl)-2-pentenes 29a, 29b, and 29c, respectively, in 84-90% yields. Of particular interest is that 29a-c are isomerized to their corresponding 2-(arylsulfonyl)-1-phenyl-5-(trimethylsilyl)-3-pentenes 30a-c, respectively, which then undergo conjugative eliminations of their arylsulfonyl and their trimethylsilyl groups to give (E)-5-phenyl-1,3-pentadiene (33) in 56-63% yields upon reactions with TBAF in THF at 25°C. Further, 27b reacts with 1,3-dichloropropane to form 1-chloro-4-(4-methylphenylsulfonyl)-7-(trimethylsilyl)-4-heptene (35) which is cyclized by n-BuLi to 1-(4-methylphenylsulfonyl)-1-(3-(trimethylsilyl)-1-propenyl)cyclobutane (37, 67%). Elimination of 37 by TBAF then gives allylenecyclobutane (34, n = 3, 84%) simply. This study thus reveals that 9, 25, and 26 have outstanding potential as 1-(1,3-butadienyl) anion (7) and 1,1-(1,3-butadienyl) dianion (8) synthons.

Full text of DOI:10.1021/jo970546c

J . Org. Chem. 1998, 63, 4193-4198
4193
(E)-1-(P h en ylsu lfon yl)-4-(tr im eth ylsilyl)-1-bu ten e: An
Ad va n ta geou s Syn th etic Equ iva len t for th e 1-(1,3-Bu ta d ien yl)
An ion a n d th e 1,1-(1,3-Bu ta d ien yl) Dia n ion
Timothy P. Meagher and Harold Shechter*
Department of Chemistry, The Ohio State University, Columbus, Ohio 43210
Received March 25, 1997
The (E)-1-(arylsulfonyl)-4-(trimethylsilyl)-1-butenes 9, 25, and 26 are prepared by CuCl2-promoted
and by photolytic additions of their precursor 1-arylsulfonyl chlorides and bromides to 4-(trimeth-
ylsilyl)-1-butene (14) and then dehydrohalogenation of the resulting 1-(arylsulfonyl)-2-halo-4-
(trimethylsilyl)butanes 15a , 15b , 23a , and 23b with KOH, LDA, or n-BuLi. Silylbutene 14 is
obtained from reaction of [(trimethylsilyl)methyl]magnesium chloride (16, X ) Cl) and allyl bromide
(17) and better by protiodesilylations of (E)- and (Z)-1,4-bis(trimethylsilyl)-2-butenes (20) with
sulfuric or trifluoroacetic acids. (Arylsulfonyl)(trimethylsilyl)-1-butenes 9, 25, and 26 are converted
efficiently by LDA or n-BuLi at -78 °C to 1-(arylsulfonyl)-1-lithio-4-(trimethylsilyl)-1-butenes 10,
27a , and 27b, respectively. Reactions of 27a and 27b with deuterium oxide yield (E)-1-(4-
chlorophenylsulfonyl)-1-deuterio-4-(trimethylsilyl)-1-butene (28a , 83%) and (E)-1-deuterio-1-(4-
methylphenylsulfonyl)-4-(trimethylsilyl)-1-butene (28b, 89%), respectively. 1-Lithio derivatives 10,
27a , and 27b undergo benzylations by benzyl bromide in THF/HMPA with retention of the positions
of their olefinic double bonds to give the (E)-2-(arylsulfonyl)-1-phenyl-5-(trimethylsilyl)-2-pentenes
29a , 29b, and 29c, respectively, in 84-90% yields. Of particular interest is that 29a -c are
isomerized to their corresponding 2-(arylsulfonyl)-1-phenyl-5-(trimethylsilyl)-3-pentenes 30a -c,
respectively, which then undergo conjugative eliminations of their arylsulfonyl and their trimeth-
ylsilyl groups to give (E)-5-phenyl-1,3-pentadiene (33) in 56-63% yields upon reactions with TBAF
in THF at 25 °C. Further, 27b reacts with 1,3-dichloropropane to form 1-chloro-4-(4-methylphen-
ylsulfonyl)-7-(trimethylsilyl)-4-heptene (35) which is cyclized by n-BuLi to 1-(4-methylphenylsul-
fonyl)-1-(3-(trimethylsilyl)-1-propenyl)cyclobutane (37, 67%). Elimination of 37 by TBAF then gives
allylenecyclobutane (34, n ) 3, 84%) simply. This study thus reveals that 9, 25, and 26 have
outstanding potential as 1-(1,3-butadienyl) anion (7) and 1,1-(1,3-butadienyl) dianion (8) synthons.
In tr od u ction
(E)- and (Z)-1-(phenylsulfonyl)-4-(trimethylsilyl)-2-
butenes (1) are converted by lithiation and alkylation to
1-substituted-2-butenes 3 (eq 1) and 1,1-disubstituted-
2-butenes 5 (eq 2) which are eliminated efficiently by
TBAF at -20 to 0 °C to their respective 1-substituted-
1,3-butadienes 4 and 1,1-disubstituted-1,3-butadienes
6.1a,b,2 In these sequences 1 functions as an excellent
synthon for the 1-(1,3-butadienyl) anion (7) and the 1,1-
(1,3-butadienyl) dianion (8) and dienes 4 and 6 are
essentially totally (100-96%) of (E) stereochemistry.1a,b,2
Resu lts a n d Discu ssion
Now reported is that (E)-1-(phenylsulfonyl)-4-(tri-
methylsilyl)-1-butene (9) is also an excellent synthon for
7 (eq 3) and 8 (eq 4), respectively. The new methodolo-
gies involve (1) lithiation of 9 with n-BuLi or LDA,
alkylation of 10, isomerization of 11 by TBAF to (E)- and
(1) (a) Hsiao, C.-N.; Shechter, H. Tetrahedron Lett. 1984, 25, 1219.
(b) Meagher, T.; Yet, L.; Hsiao, C.-N.; Shechter, H. J . Org. Chem. 1998,
63, 4181.
(2) For previous studies of eliminations of vic-trimethylsilyl(phe-
nylsulfonyl) derivatives to olefins, see: (a) Kocienski, P. J . Tetrahedron
Lett. 1979, 2649. (b) Kocienski, P. J . J . Org. Chem. 1980, 45, 2037. (c)
Hsaio, C.-N.; Shechter, H. Tetrahedron Lett. 1982, 3455. (d) Eisch, J .
J .; Behrooz, M.; Dua, S. K. J . Organomet. Chem. 1985, 285, 121. (e)
Hsaio, C.-N.; Shechter, H. J . Org. Chem. 1988, 53, 2688. (f) Kim, S.
H.; J in, Z.; Ma, S.; Fuchs, P. L. Tetrahedron Lett. 1995, 4013 and
references therein.
(Z)-2-butenes 12, and spontaneous elimination of 12 to
4 by the fluoride ion present and (2) allylic deprotonation
of 11 by n-BuLi, alkylation of 13, and reaction of
2-butenes 5 with TBAF to yield 6. As will be demon-
strated, using 9 is as efficient and less expensive than 1.
Further, varied γ-silyl-R,â-unsaturated sulfones should
be preparable as above and the methods now described
S0022-3263(97)00546-X CCC: $15.00 © 1998 American Chemical Society
Published on Web 06/05/1998

4194 J . Org. Chem., Vol. 63, No. 13, 1998
Meagher and Shechter
chlorides as catalyzed by cupric chloride (eq 5)7a-g and
by photolytic addition of arylsulfonyl bromides (eq 5).7h
Of importance is that reaction of 14 with benzenesulfonyl
chloride in acetonitrile/CH2Cl2 in the presence of cupric
chloride and triethylamine hydrochloride at 105-115 °C
for 17 h in a pressure container yields 15a (69%).
Addition of benzenesulfonyl chloride to 14 as above at
temperatures above 100 °C is very slow. Use of the
higher boiling solvent isobutyronitrile (bp 107-108 °C)
instead of acetonitrile/CH2Cl2 allows satisfactory addition
of benzenesulfonyl chloride to 14 without using pressure
equipment. Increasing the solubility of cupric chloride
in 2-ethoxyethyl ethyl ether using TDA-1 in place of
triethylamine hydrochloride increases the rate of addition
of benzenesulfonyl chloride to 14 to give 15a (51%). The
2-chloro-1-(phenylsulfenyl)-4-(trimethylsilyl)butane (22,
8%) formed as a byproduct in the latter synthesis is
oxidized efficiently by m-chloroperbenzoic acid (MCPBA)
to 15a (92%). Chlorosilyl sulfone 15a is an oil that can
be stored indefinitely without significant decomposition.
should be extendable to preparation of various conjugated
diene derivatives.
Synthesis of 9 from 4-(trimethylsilyl)-1-butene (14) as
summarized in eq 5 has now been developed as follows.
Reaction of [(trimethylsilyl)methyl]magnesium bromide
(16, X ) Br) and allyl bromide (17) is reported to yield
14 (25%, eq 6).3. In the present work coupling of 17 with
[(trimethylsilyl)methyl]magnesium chloride (16, X ) Cl),4
prepared from magnesium and commercially available
(chloromethyl)trimethylsilane, also gives 14 in only 22-
27% yields. A more satisfactory large-scale method for
2-Chloro-1-(4-chlorophenylsulfonyl)-4-(trimethylsilyl)bu-
tane (23a ) and 2-chloro-(4-methylphenylsulfonyl)-4-(tri-
methylsilyl)butane (23b), prepared by addition of 4-chlo-
rophenylsulfonyl chloride and of 4-methylphenylsulfonyl
chloride to 14 as above, are stable crystalline solids that
also can be used satisfactorily in the present synthesis
methodology.
Arylsulfonyl bromides add to olefins photolytically to
give vicinal arylsulfonyl(bromo)alkanes.7h-j In a present
method irradiation of benzenesulfonyl bromide in 14 in
THF with an ordinary 500 W light bulb yields 15b (eq 5,
48%).8 Similarly, p-toluenesulfonyl bromide and 14 in
benzene give 24 (62%). The photochemical addition
reactions can be monitored conveniently by GC methods,
and the unreacted bromides are separated easily from
the reaction products by column chromatography. Dur-
ing chromatography of 24 minor dehydrobromination
preparing 14 (eq 7) involves reductive-silylation of 1,3-
butadiene (18) with lithium (2 equiv) and trimethylsilyl
chloride (2 equiv, 40% conversion) to 20.5 Protiodesilyl-
ation of 20 with sulfuric acid in pentane or trifluoroacetic
acid in CCl4 occurs with rearrangment to give 14 (54-
66%) and hexamethyldisiloxane (21).6 Simple distilla-
tions yield large quantities of mixtures of 14 and 21 in
∼2:1 ratio which are usable without further purification.
If desired, rectification of mixtures of 14 and 21 allows
preparation of pure 14.
(7) For previous examples of such additions, see: (a) Cristol, S. J .;
Reeder, J . A. J . Org. Chem. 1961, 26, 2182. (b) Vasil’eva, M. A.;
Bychkova, T. I.; Kushnarev, D. F.; Rozova, T. I.; Kalabina, A. V. Zh.
Org. Khim. 1977, 13, 283. (c) Asscher, M.; Vofsi, D. J . Chem Soc. 1964,
4962. (d) Amiel, Y. Tetrahedron Lett. 1971, 661. (e) Yoshiaki, K.; Muria,
S.; Sonoda, N.; Tsutsumi, S. Organomet. Chem. Synth. 1972, 1, 465.
(f) Dunoques, J .; Pillot, J .-P.; Duffaut, N.; Calas, R. C. R. Acad. Sci.
Ser. C 1974, 278, 467. (g) Pillot, J . P.; Dunoques, J .; Calas, R. Synthesis
1977, 469. (h) Zakharkin, L. I.; Zhigareva, G. C. Zh. Org. Khim. 1973,
9, 891. Boll, W. Liebigs Ann. Chim. 1979, 1655. (i) Kalabina, A. V.;
Vasil’eva, M. A.; Bychkova, T. I. Zh. Org. Khim. 1979, 15, 268. (j)
Doomes, E.; Clarke, U.; Neitzel, J . J . Org. Chem. 1987, 52, 1540.
(8) An alternate method for preparing 11, 22, and 23 which has not
been evaluated in this work is addition of arylsulfenyl chlorides to 10
followed by oxidation with percarboxylic acids: Hopkins, P. B.; Fuchs,
P. L. J . Org. Chem. 1978, 43, 1208.
Halo(silyl)sulfonylbutanes such as 15a and 15b are
presently prepared from 14 by addition of arylsulfonyl
(3) Hauser, C. R.; Hance, C. R. J . Am. Chem. Soc. 1952, 74, 5091.
(4) Sommer, L. H.; Goldberg, G. M.; Gold, J .; Whitmore, F. C. J .
Am. Chem. Soc. 1947, 69, 980.
(5) Weyenberg, D. R.; Toporder, L. H.; Nelson, L. E. J . Org. Chem.
1968, 33, 1975.
(6) (a) Sommer, L. H.; Tyler, L. G.; Whitmore, F. C. J . Am. Chem.
Soc. 1948, 70, 2872. (b) Salimareeva, I. M.; Zhebarov, O. Z.; Bogatova,
N. G.; Yurev, V. P. Zh. Obskch. Khim. 1981, 51, 420.

(E)-1-(Phenylsulfonyl)-4-(trimethylsilyl)-1-butene
J . Org. Chem., Vol. 63, No. 13, 1998 4195
occurs to give 25 (5%). Elimination product 25 exhibits
a single set of 13C NMR absorptions and is assigned (E)
stereochemistry from its 1H NMR because its olefinic
protons exhibit coupling of 15.0 Hz.
27a , and 27b for 0.2 h at -78 °C and then adding benzyl
bromide followed by HMPA gives benzylated products
29a , 29b, and 29c in 89, 84, and 90% yields, respectively.
The benzylations are accelerated by HMPA. Keeping 10,
27a , and 27b at -78 °C for 1.5 h before adding benzyl
bromide and then HMPA leads to 29a (67%), 29b (63%),
and 29c (45%) in significantly lower yields. Further,
warming 27a from -78 to 25 °C in 1 h and then adding
benzyl bromide and HMPA give only a 30% yield of 29c.
Lithio derivatives 10, 27a , and 27b decompose at -78
°C and should be derivatized shortly after generation.
The products of thermal decomposition of 10, 27a , and
27b are as yet unknown. Of further interest is that lithio
allyl derivative 2 reacts much more rapidly than 10, 27a ,
or 27b with benzyl bromide. The relative unreactivities
of 10, 27a , and 27b are interpretable on the basis that
their lithium vinyl bonds are tighter than that for the
lithium allyl moiety in 2.
Halosulfones 15a , 15b, 23a , and 23b are eliminated
efficiently by various bases.9 Reaction of 15a with
potassium hydroxide in THF-water at room temperature
gives 9 (91%). Additionally, 23a is converted by n-BuLi
in THF at -78 °C to 26 (98%). Further, treatment of
23b with LDA at -78 °C and then aqueous ammonium
chloride yields 25 (93%). Also, photoaddition of an
arylsulfonyl bromide to 14 (eq 5) followed by dehydro-
bromination of the photoproduct can be combined into a
one-pot procedure. Thus, irradiation of 14, 21, and
p-toluenesulfonyl bromide in THF followed by addition
of aqueous potassium hydroxide results in elimination
of 15b to yield 25 (42%). As for 25, 9 and 26 are assigned
(E) stereochemistries because they each have 13C NMR
1
absorptions for a single isomer and H NMR couplings
of 15.0 Hz for their olefinic hydrogens.
Generation and determination of the behavior of vinyl
sulfone R-anions similar to 10 have had limited study.10
Sulfonyl-1-butenes 9, 26, and 25 are presently found to
be readily converted to 10, 27a , and 27b, respectively,
with LDA or n-BuLi in THF at -78 °C. The deprotona-
tions with LDA are essentially complete within seconds;
n-BuLi requires from 1 to 15 min. Deuterations of 27a
and 27b with D2O then yield (E)-1-deuterio-1-butenes
28a (83%) and 28b (89%), respectively, assigned spec-
trally and intuitively as follows. Deuteriobutene 28a has
a single set of 13C NMR absorbances, and its 1H NMR
reveals 79% deuterium at its R-position as determined
from its vinyl proton resonance at δ 6.30. Since the
remaining vinyl proton absorbances (δ 6.9-7.1) are
complex, the stereochemistry of 28a was not rigorously
assigned. From the above spectral information and
subsequent chemistry, the stereochemistry of 28a is
presumed to be (E). Similar information leads to the
provisional (E) stereochemical assignment of 28b.
Benzyl derivatives 29a -c are assigned by spectral
methods. Each product gives a single set of 13C NMR
absorbances, thus indicating that only single isomers are
present. (E) stereochemistries are assigned to 29a and
29c because proton NOE differences reveal that the
hydrogens at C-1 (benzyl) and C-4 (allyl) are on cis carbon
atoms. Irradiation of the allyl (C-4) protons (δ 2.15) of
29a results in enhancement of the NMR of its benzyl (C-
1) hydrogen (δ 3.68, 5.71%). Similarly, irradiation of the
hydrogen at C-4 in the allyl group of 29c (δ 2.1-2.2) gives
an increase in the NMR absorption of its benzyl (C-1)
hydrogen of 5.66% (δ 3.69). On the basis of the results
with 29a and 29c, the stereochemistry of 29b is pre-
sumed to be (E).
Attention next turned to isomerizations of 29a , 29b,
and 29c to 30a , 30b, and 30c, respectively, followed by
elimination of their trimethylsilyl and their arylsulfonyl
groups.
R-Alkenyl (31) and allyl (32) sulfones generally inter-
convert under basic conditions (eq 8), and the equilibria
usually favor the allyl (unconjugated) isomers 32 heavily
when R′ is aryl or alkyl.11
The behaviors of R-lithio vinyl sulfones 10, 27a , and
27b with benzyl bromide were then investigated. The
lithiates, prepared in situ from 15a , 23a , and 23b,
respectively, with 2 equiv of LDA or n-BuLi at -78 °C,
were stirred for various times and then benzyl bromide
was added followed by HMPA (2.1 equiv). Stirring 10,
Desirable methodology for 29a -c will be to combine
deconjugation to 30a -c by fluoride ion functioning as a
base followed by rapid elimination of 30a -c to (E)-5-
phenyl-1,3-pentadiene (33). These conditions are met
(9) (a) â-Halo sulfones are readily dehydrohalogenated by hydroxide
bases7c or tertiary amines.9b (b) Skell, P. S.; McNamara, J . H. J . Am.
Chem. Soc. 1957, 79, 85.
(10) (a) Eisch, J . J .; Galle, J . E. J . Org. Chem. 1979, 44, 3277. (b)
Eisch, J . J .; Galle, J . E. J . Org. Chem. 1979, 44, 3279.

4196 J . Org. Chem., Vol. 63, No. 13, 1998
Meagher and Shechter
to a mixture of trimethylsilyl chloride (259.0 g, 2.38 mol),
lithium (17.3 g, 2.50 mol), and THF (350 mL) at 0-10 °C under
argon. The mixture was then stirred for 24 h, filtered, washed
with H2O and brine, and concentrated to a clear colorless
liquid. Fractional distillation yielded 20 (94.50 g, 40%): bp
90-95 °C (38 mmHg), whose IR and 1H NMR spectra agree
with the literature.12
4-(Tr im eth ylsilyl)-1-bu ten e (14). Meth od A. Sulfuric
acid (36.8 g, 0.38 mol, 98%) was added in 0.5 h to 20 (75.8 g,
0.38 mol) in pentane (300 mL) at 0 °C. The mixture was
stirred further for 0.5 h. The pentane layer was washed with
H2SO4 until hexamethyldisiloxane (21) was no longer detected
by GC, washed with saturated aqueous NaHCO3 and brine,
dried (MgSO4), and fractionally distilled in a packed column
(glass helices; 20 × 1 cm) to give 14 (26.4 g, 54%): bp 112-
115 °C. The IR and 1H NMR spectra of 14 agree with
literature data.6b
Meth od B. Trifluoroacetic acid (2.8 g, 24.9 mmol) was
slowly added to 20 (5.0 g, 24.9 mmol) in CCl4 under argon at
3 °C. The mixture was stirred for 1.5 h and poured into
saturated aqueous NaHCO3/ice. The organic phase was
washed with H2O and brine, dried (MgSO4), and fractionally
distilled (Fenske glass ring, Hempel column; 10 × 1 cm) to
yield 14 (2.10 g, 66%) of satisfactory spectral properties: bp
112-115 °C.6b
simply at present by treatment of 29a -c with 1 equiv of
TBAF at room temperature to give 33 in 56, 63, and 59%
yields, respectively. The above method of synthesis of
33 in quantity is cheaper and just as convenient as
synthesis of 1 and its conversion by n-BuLi and benzyl
bromide to 30a (R ) CH2C6H5) followed by detrimethyl-
silylphenylsulfonylation by TBAF as previously de-
scribed.1b
1,1-Cycloalka-1,3-butadienes (34, n ) 2-5) have been
prepared previously from 1.1b Preparation of 34 (n ) 3)
from 25 (eq 9) then became of interest. The lithio
derivative 27b of 25 has now been found to be monoalkyl-
Meth od C. [(Trimethylsilyl)methyl]magnesium chloride
(16, X ) Cl)13 was prepared from (chloromethyl)trimethylsilane
(20 g, 0.16 mol) and magnesium (3.97 g, 0.16 mol) in Et2O (50
mL). The solution was cooled to 0 °C, and allyl bromide (17,
28 g, 0.23 mol) was added. The resulting mixture was refluxed
for 5 h, cooled, and poured into saturated aqueous NH4Cl/ice.
The organic layer was washed with H2O and brine, dried
(MgSO4), and distilled to give 14 (6.0 g, 29%): bp 112-115
°C.6b
2-Ch lor o-1-(4-ch lor op h en ylsu lfon yl)-4-(t r im et h ylsil-
yl)bu ta n e (23a ). 4-Chlorobenzenesulfonyl chloride (6.5 g,
30.7 mmol), 14 (4.0 g, 31.1 mmol), acetonitrile (2 mL), CH2Cl2
(10 mL), cupric chloride (0.41 g, 3.0 mmol), and triethylamine
hydrochloride (0.64 g, 4.6 mmol) were placed in a threaded
glass pressure tube and deoxygenated for 1.5 h. The tube was
sealed and heated to 105-115 °C for 17 h, cooled, and then
opened. The mixture was taken up in Et2O, washed with H2O,
10% HCl, and 10% aqueous Na2CO3, dried (MgSO4), and
concentrated to a white semisolid (9.46 g). Column chroma-
tography (silica gel; ethyl acetate-hexane, 0-5%) gave 23a
(7.28 g, 69% yield) as a white solid and 4-chlorobenzenesulfonyl
chloride (1.71 g, 26% recovery). Recrystallization of the
product from hexane yielded pure 23a , a white solid: mp 82-
84 °C; 1H NMR (CDCl3) δ -0.01 (s, 9 H), 0.4-0.7 (m, 2 H),
1.6-1.9 (m, 2 H), 3.4-3.6 (m, 2 H), 4.26 (quin, J ) 6.0 Hz, 1
H), 7.53 (d, J ) 8.7 Hz, 2 H), 7.86 (d, J ) 8.7 Hz, 2 H); 13C
NMR (CDCl3) δ -1.9 (q), 12.4 (t), 32.9 (t), 56.9 (d), 62.9 (t),
129.6 (d), 129.7 (d), 138.1 (s), 140.8 (s); mass spectrum, m/e
calcd for C12H17Cl2O2SSi (M+ - CH3, 35Cl) 323.0096, found
323.0110. Anal. Calcd for C13H20Cl2O2SSi: C, 46.01; H, 5.94.
Found: C, 46.38; H, 5.86.
2-Ch lor o-1-(4-m e t h ylp h e n ylsu lfon yl)-4-(t r im e t h yl-
silyl)bu ta n e (23b). A stirred solution of 14 (10.0 g, 77.9
mmol), cupric chloride (1.0 g, 7.8 mmol), triethylammonium
chloride (2.1 g, 15.6 mmol), and isobutyronitrile (30 mL) was
deoxygenated with argon for 1 h. p-Toluenesulfonyl chloride
(14.8 g) was then added to the clear dark red solution. The
mixture was refluxed under argon. After 24 h, 14 was not
detected by GC. Saturated aqueous NaHCO3 was added to
the reaction mixture which was then refluxed for 3.5 h. After
cooling, the reaction product was worked up as in the synthesis
of 23a and concentrated to a light brown solid (18.05 g).
Column chromatography (silica gel, ethyl acetate-hexane,
0-1%) gave 23b (13.14 g, 53%) as a white crystalline solid:
mp 79-80 °C (from hexane); 1H NMR (CDCl3) δ 0.00 (s, 9 H),
ated by 1,3-dichloropropane to give (3-chloropropyl)
derivative 35. Reaction of 35 with n-BuLi results in
removal of an allyl proton at C-6 and generation of lithio
allyl intermediate 36. Ring closure with displacement
of chloride ion from 36 then gives 1-(1-propenyl)cyclobu-
tane 37 in 67% yield. Conjugative elimination of the
trimethylsilyl and the 4-methylbenzenesulfonyl groups
in 37 by TBAF at 0 °C in THF then yields allylenecy-
clobutane (34, n ) 3, 84%). The overall sequence from
25 to 34, n ) 3, is satisfactory and at least the equal to
that found previously for 1, n-BuLi, 1,3-dichloropropane,
n-BuLi, and TBAF.1b Further, the present methodology
has excellent potential for preparing cycloalkadienes such
as 34 (n ) 2, 4, and 5) as well as varied 1,1-disubstituted-
1,3-butadienes (6).
In conclusion, 9, 25, and 26 serve as excellent synthons
for the 1-(1,3-butadienyl) anion (7) and the 1,1-(1,3-
butadienyl) dianion (8).
Exp er im en ta l Section
Gen er a l Con sid er a tion s. Product separations, spectro-
scopic determinations, analyses, purification of solvents, and
typical procedures in various experiments have been handled
as previously detailed.1b
(E)-1,4-Bis(tr im eth ylsilyl)-2-bu ten e (20). 1,3-Butadiene
(18, 62.0 g, 1.26 mol) condensed at -78 °C was added in 4 h
(11) (a) Hine, J .; Linden, S.-M.; Wang, A.; Thiagarajan, V. J . Org.
Chem. 1980, 45, 2821. (b) Hine, J .; Skoglund, M. J . J . Org. Chem. 1982,
47, 476. (c) Cram, D. J . Fundamentals of Carbanion Chemistry;
Academic Press: New York, 1965; pp 32-65. (d) For recent discussion
of the origins of such differences, see ref 1b.
(12) Weyenberg, D. R.; Toporder, L. H.; Nelson, L. E. J . Org. Chem.
1968, 33, 1975.
(13) Sommer, L. H.; Goldberg, G. M.; Gold, J .; Whitmore, F. C. J .
Am. Chem. Soc. 1946, 68, 481.

(E)-1-(Phenylsulfonyl)-4-(trimethylsilyl)-1-butene
J . Org. Chem., Vol. 63, No. 13, 1998 4197
0.4-0.7 (m, 2 H), 1.6-2.0 (m, 2 H), 2.47 (s, 3 H), 3.52 (d, J )
6.3 Hz, 2 H), 4.2 (m, 1 H), 7.37 (d, J ) 7.9 Hz, 2 H), 7.81 (d, J
) 8.3 Hz, 2 H); 13C NMR (CDCl3) δ -1.9 (q), 12.4 (t), 21.6 (q),
32.8 (t), 57.1 (d), 62.9 (t), 128.2 (d), 130.0 (d), 136.8 (s), 145.1
(s); mass spectrum, m/e calcd for C13H20ClO2SSi (M+ - CH3,
35Cl) 303.0642, found 303.0663. Anal. Calcd for C14H23ClO2-
SSi: C, 52.71; H, 7.27. Found: C, 52.60; H, 7.20.
diluted with Et2O. The organic layer was washed with H2O
and brine, dried (MgSO4), and concentrated to 9 (0.40 g, 91%),
a clear colorless oil: 1H NMR (CDCl3) δ -0.03 (s, 9 H), 0.5-
0.6 (m, 2 H), 2.1-2.2 (m, 2 H), 6.30 (dt, J ) 15.0, 1.6 Hz, 1 H),
7.03 (dt, J ) 15.0, 6.3 Hz, 1 H), 7.4-7.6 (m, 3 H), 7.8-7.9 (m,
2 H); 13C NMR (CDCl3) δ -1.9 (q), 14.4 (t), 26.1 (t), 127.5 (d),
129.1 (d), 129.3 (d), 133.1 (d), 140.8 (s), 149.5 (d). The 1H NMR
and IR of 9 are consistent with literature values.1a,b,14
2-Ch lor o-1-(p h en ylsu lfon yl)-4-(t r im et h ylsilyl)b u t a n e
(15a ) a n d 2-Ch lor o-1-(p h en ylsu lfen yl)-4-(t r im et h yl-
silyl)bu ta n e (22). A stirred mixture of benzenesulfonyl
chloride (16.70 g, 94.6 mmol), cupric chloride (1.27 g, 9.44
mmol), and TDA-1 (6.90 g, 21.4 mmol) in 2-ethoxyethyl ether
(30 mL) was deoxygenated for 1.25 h and then heated to 130
°C. A solution of 14 (12.1 g, 9.43 mmol) and 21 (6.3 mL) was
added via syringe pump (2.5 mL/h for 4.0 h, then 13.3 mL/h
for 11.0 h) to the red-brown reactant solution. The mixture
was then heated for 11 h at 120-124 °C. The brown solution
was worked up as described for 23a and concentrated to a dark
oil (31.45 g). Column chromatography (silica gel; ethyl acetate-
hexane, 0-3%) yielded 22 (1.97 g, 8%) as a clear colorless oil
[1H NMR (CDCl3) δ 0.03 (s, 9 H), 0.5-0.8 (m, 2 H), 1.6-2.0
(m, 2 H), 3.3 (AB q, J ) 13.8 Hz), 3.9-4.0 (m, 1 H), 7.1-7.5
(m, 5 H); 13C NMR (CDCl3) δ -1.9 (q), 12.5 (t), 31.1 (t), 41.4
(t), 63.9 (d), 126.6 (d), 129.0 (d), 130.1 (d), 135.4 (s); mass
spectrum, m/e calcd for C13H21ClSSi (M+, 35Cl) 272.0822, found
272.0863] and 15a (14.82 g, 51%): 1H NMR (CDCl3) δ -0.05
(s, 9 H), 0.4-0.7 (m, 2 H), 1.6-1.9 (m, 2 H), 3.4-3.5 (m, 2 H),
4.2-4.3 (m, 1 H), 7.4-7.9 (m, 5 H); 13C NMR (CDCl3) δ -2.0,
12.2, 32.6, 56.9, 62.6, 128.0, 129.2, 133.9, 139.4; mass spec-
trum, m/e calcd for C21H18ClO2SSi (M+ - CH3, 35Cl) 289.0485,
found 289.0482.
(E)-1-(4-Met h ylp h en ylsu lfon yl)-4-(t r im et h ylsilyl)-1-
bu ten e (25). P r oced u r e B. A stirred solution of 14 (5.0 g,
38.9 mmol), 21 (2.6 g), and p-toluenesulfonyl bromide (9.2 g,
39.1 mmol) in THF was deoxygenated 30 min with argon and
photolyzed for 14 h with a 500 W incandescent bulb. Aqueous
potassium hydroxide (30 mL, 0.6 M, 18 mmol) was added, and
the resulting mixture was stirred for 1 h. The organic phase
was worked up as for 14 (method B) and concentrated to a
cloudy yellow oil (6.98 g) which solidified. Recrystallization
from methanol gave 25 (4.37 g, 42%) as a white solid: mp
1
48.5-49.5 °C (from pentane); H NMR (CDCl3) δ -0.03 (s, 9
H), 0.5-0.6 (m, 2 H), 2.1-2.2 (m, 2 H), 2.41 (s, 3 H), 6.28 (dt,
J ) 15.0, 1.6 Hz, 1 H), 6.99 (dt, J ) 15.0, 6.3 Hz, 1 H), 7.30 (d,
J ) 7.9 Hz, 2 H), 7.74 (d, J ) 8.3 Hz, 2 H); 13C NMR (CDCl3)
δ -1.9, 14.4, 21.5, 26.0, 127.5, 129.6, 129.7, 137.9, 144.0, 148.8;
mass spectrum m/e calcd for C14H22O2SSi (M+) 282.1110, found
282.1117. Anal. Calcd for C14H22O2SSi: C, 59.52; H, 7.85.
Found: C, 59.34; H, 7.93.
P r oced u r e C. n-BuLi (1.27 mL, 3.30 mmol, 2.60 M in
hexane) was added to a stirred solution of diisopropylamine
(0.35 g, 3.45 mmol) and THF (30 mL) under argon at -78 °C.
After 20 min, 23b (0.96 g, 3.01) in THF (4 mL) was added (2
min). After being stirred at -78 °C for 10 min, the mixture
was quenched with aqueous saturated NH4Cl and allowed to
warm to room temperature, and CH2Cl2 was added. The
organic phase was washed with H2O and brine, dried, (MgSO4),
and concentrated to a viscous oil which solidified on standing.
Column chromatography (Florisil; ethyl acetate, 5%) yielded
25 (0.79 g, 93%) as a clear colorless oil which crystallized to a
white solid with properties identical to that prepared previ-
ously.
(E)-1-(4-Ch lor op h en ylsu lfon yl)-4-(t r im et h ylsilyl)-1-
bu ten e (26). Procedure C with n-BuLi and 23a followed by
workup yielded 26 (0.44 g, 98%), a fluffy white solid: mp 73-
74 °C; 1H NMR (CDCl3) δ 0.00 (s, 9 H), 0.5-0.7 (m, 2 H), 2.1-
2.3 (m, 2 H), 6.28 (dt, J ) 15.0, 1.6 Hz), 7.05 (dt, J ) 15.0, 6.3
Hz), 7.49 (d, J ) 8.8 Hz, 2 H), 7.80 (d, J ) 8.8 Hz, 2 H); 13C
NMR (CDCl3) δ -1.9 (q), 14.5 (t), 26.2 (t), 129.0 (d, coincident
peaks), 129.5 (d), 139.4 (s), 139.9 (s), 150.3 (d); mass spectrum
m/e calcd for C13H18ClSSiO2 (M+ - H) 301.0485, found 301.0476.
Anal. Calcd for C13H18ClSSiO2: C, 51.55; H, 6.32. Found: C,
51.36; H, 6.34.
(E)-1-(4-Ch lor op h en ylsu lfon yl)-1-d eu ter io-4-(tr im eth -
ylsilyl)-1-bu ten e (28a ). Procedure C involving addition of
D2O to a solution from 26, n-BuLi, diisopropylamine, and THF,
workup as for 9, and column chromatography (Florisil; ethyl
acetate-hexane, 1-2%) gave 28a (83%), a white solid: mp 72-
73 °C; 1H NMR (CDCl3) δ 0.00 (s, 9 H), 0.5-0.6 (m, 2 H), 2.1-
2.3 (m, 2 H), 6.30 (dt, J ) 15.0, 1.6 Hz, 79% deuterium
incorporation), 6.9-7.1 (m, 2 H), 7.50 (dt, J ) 8.8 Hz, 2 H),
7.80 (d, J ) 8.7 Hz, 2 H); 13C NMR (CDCl3) δ -1.9 (q), 14.5 (t),
26.2 (t), 129.1 (d), 129.5 (d), 139.5 (s), 139.9 (s), 150.2 (d); mass
spectrum m/e calcd for C12H15DClO2SSi (M+ - CH3, 37Cl)
290.0362, found 290.0398.
(E)-1-Deu ter io-1-(4-m eth ylp h en ylsu lfon yl)-4-(tr im eth -
ylsilyl)-1-bu ten e (28b). Procedure C with 27b gave 28b
(89%), a colorless oil which solidified: mp 48-49 °C (from
pentane); 1H NMR (CCl4) δ 0.00 (s, 9 H), 0.5-0.6 (m, 2 H),
2.1-2.5 (m, 2 H), 2.45 (s, 3 H), 6.24 (J ) 15 Hz, >90%
deuterium incorporated), 6.95 (bt, J ) 7 Hz, 1 H), 7.32 (d, J )
8 Hz, 2 H), 7.74 (d, J ) 8 Hz, 2 H); mass spectrum m/e calcd
for C14H21DO2SSi (M+) 283.1173, found 283.1158.
Syn th esis of 15a by Oxid a tion of 22. MCPBA (0.25 g,
1.23 mmol, 85%) was added to a solution of 22 (0.12 g, 0.43
mmol) in CH2Cl2 (3 mL) at 0 °C. The white suspension was
warmed to room temperature and then stirred for 1.5 h. The
mixture was dissolved in Et2O, washed with saturated aqueous
sodium metabisulfite, saturated aqueous NaHCO3, and brine,
dried (MgSO4), and concentrated to 15a (0.12 g, 92%). The
1H NMR and IR of 15a are identical to those of a previous
sample.
2-Br om o-1-(p h en ylsu lfon yl)-4-(t r im et h ylsilyl)b u t a n e
(15b). P r oced u r e A. A stirred solution of 14 (5.80 g, 45.2
mmol), 21 (2.99 g), benzenesulfonyl bromide (10.0 g, 45.2
mmol), and THF (30 mL) in Pyrex was deoxygenated with
argon for 20 min and then irradiated with a 500 W clear
incandescent bulb. After 3.5 h, the mixture was concentrated
to a clear colorless viscous oil (15.26 g). Column chromatog-
raphy (silica gel; ethyl acetate-hexane, 0-5%) yielded ben-
zenesulfonyl bromide (4.98 g, 50% recovery) and then 15b (7.51
g, 48%), a clear, colorless oil: 1H NMR (CDCl3) δ -0.01 (s, 9
H), 0.5-0.7 (m, 2 H), 1.7-2.0 (m, 2 H,), 3.5-3.7 (m, 2 H), 4.3-
4.4 (m, 1H), 7.5-7.9 (m, 4 H); 13C NMR (CDCl3) δ -1.9, 13.5,
33.1, 48.5, 63.1, 128.0, 129.4, 134.0, 139.5; mass spectrum, m/e
calcd for C12H18BrO2SSi (M+ - CH3, 79Br) 332.9980, found
332.9988, (M+ - CH3, 81Br) 336.0038, found 336.0006.
2-Br om o-(4-m e t h ylp h e n ylsu lfon yl)-4-(t r im e t h ylsil-
yl)bu ta n e (24). Procedure A with p-toluenesulfonyl bromide
using benzene as the reaction solvent gave after 29 h parent
bromide (26% recovery) as the first eluent followed by 24 (62%),
a white crystalline solid: mp 72 °C from hexane; 1H NMR
(CDCl3) δ 0.0 (s, 9 H), 0.5-0.7 (m, 2 H), 1.7-2.0 (m, 2 H), 2.45
(s, 3 H), 3.65 (m, 2 H), 4.2-4.4 (m, 1 H), 7.37 (d, J ) 8.2 Hz,
2 H), 7.80 (d, J ) 8.2 Hz, 2 H); irradiation of the multiplet at
δ 4.2-4.4 simplified δ 3.65 to a singlet and simplified δ 1.7-
2.0 somewhat; 13C NMR (CDCl3) δ -1.9 (q), 13.5 (t), 21.6 (q),
33.1 (t), 48.7 (d), 63.2 (t), 128.1 (d), 130.0 (d), 136.6 (s), 145.1
(s); mass spectrum, m/e calcd for C13H20BrO2SSi (M+ - CH3,
79Br) 347.0136, found 347.0136, (M+ - CH3, 81Br) 349.0116,
found m/e 349.0128. Anal. Calcd for C14H23BrO2SSi: C, 46.27;
H, 6.38. Found: C, 46.52; H, 6.22. The last eluent, 25 (5%),
was identified by comparison with an authentic sample.
(E)-1-(P h en ylsu lfon yl)-4-(tr im eth ylsilyl)-1-bu ten e (9).
Potassium hydroxide (1.0 g, 17.8 mmol) in water (5 mL) was
added to 15a (0.5 g, 1.64 mmol) in THF (5 mL). The
heterogeneous mixture was stirred vigorously for 2 h and
(E)-1-P h en yl-2-(p h en ylsu lfon yl)-5-(t r im et h ylsilyl)-2-
p en ten e (29a ). P r oced u r e D. n-BuLi (1.13 mL, 2.93 mmol,
(14) Kinney, W. A.; Crouse, G. D.; Paquette, L. A. J . Org. Chem.
1983, 48, 4986.

4198 J . Org. Chem., Vol. 63, No. 13, 1998
Meagher and Shechter
2.60 M in hexane) was slowly added to 9 (0.50 g, 1.43 mmol)
in THF (10 mL) at -78 °C. The clear yellow solution was
stirred for 10 min, and then benzyl bromide (0.49 g, 2.86 mmol)
was added followed by HMPA (0.54 g, 3.02 mmol). The
mixture was warmed to room temperature and quenched with
saturated aqueous NH4Cl. The organic layer was washed with
10% HCl and brine, dried (MgSO4), filtered, and concentrated
to a light yellow mobile oil (0.57 g). Column chromatography
(silica gel, ethyl acetate, 0-5%) yielded 29a (0.45 g, 89%), a
colorless oil: 1H NMR (CDCl3) δ -0.05 (s, 9 H), 0.5-0.6 (m, 2
H), 2.0-2.2 (m, 2 H), 3.68 (s, 2 H), 6.9-7.7 (m, 11 H); NOE
experiments, irradiation of δ 2.15 enhances δ 0.5-0.6 (7.96%)
and δ 3.68 (5.71%); irradiation of δ 3.68 enhances δ 2.0-2.2
(9.03%); 13C NMR (CDCl3) δ -1.9, 15.2, 23.4, 31.9, 126.3, 128.0,
128.1, 128.3, 128.8, 132.8, 136.9, 138.4, 140.1, 146.5; mass
spectrum m/e calcd for C20H26O2SSi (M+) 358.1423, found
358.1413.
(E)-2-(4-Meth ylp h en ylsu lfon yl)-1-p h en yl-5-(tr im eth yl-
silyl)-2-p en ten e (29b). Using 25 in procedure D yielded 29b
(0.43 g, 84%), a colorless oil: 1H NMR (CDCl3) δ 0.00 (s, 9 H),
0.5-0.6 (m, 2 H), 2.1-2.2 (m, 2 H), 2.44 (s, 3 H), 3.73 (s, 2 H),
7.0-7.3 (m, 8 H), 7.69 (d, J ) 8.3 Hz, 2 H); decoupling
experiments, irradiation at δ 0.5-0.6 simplifies δ 2.1-2.2 to
a doublet; irradiation of δ 2.1-2.2 simplifies δ 0.5-0.6 to a
singlet; 13C NMR (CDCl3) δ -1.9 (q), 15.2 (t), 21.5 (q), 23.4 (t),
32.0 (t), 126.2 (d), 128.1 (d), 128.2 (d), 128.3 (d), 129.5 (d), 137.1
(s), 137.2 (s), 138.7 (s), 143.7 (s), 146.0 (d); mass spectra, m/e
calcd for C21H28O2SSi (M+) 372.1580, found 372.1569.
(E)-2-(4-Ch lor op h en ylsu lfon yl)-1-p h en yl-5-(tr im eth yl-
silyl)-2-p en ten e (29c). Procedure D with benzyl bromide and
23b gave 29c as a viscous oil which crystallized to a pink-
white solid, 90% yield: mp 75-76 °C (from hexane); 1H NMR
(CDCl3) δ -0.04 (s, 9 H), 0.5-0.6 (m, 2 H), 2.1-2.2 (m, 2 H),
3.69 (s, 2 H), 6.9-7.2 (m, 6 Hz), 7.28 (d, J ) 8.7 Hz, 2 H), 7.59
(d, J ) 8.7 Hz, 2 H); decoupling experiments, irradiation of δ
0.6 simplifies δ 2.2 to a doublet and irradiation of δ 2.2
simplifies δ 0.6 to a singlet; NOE experiments, irradiation at
δ 2.1-2.2 enhances δ 3.69 (5.66%) and δ 0.5-0.6 (7.07%);
irradiation at δ 3.69 enhances δ 2.1-2.2 (9.59%); 13C NMR
(CHCl3) δ -1.9, 15.3, 23.5, 31.9, 126.4, 128.1, 128.3, 129.0,
129.4, 136.6, 138.3, 138.8, 139.4, 147.0; mass spectrum m/e
calcd for C20H25ClO2SSi (M+, 35Cl) 392.1033, found 392.1030.
Anal. Calcd for C20H25ClO2SSi: C, 61.12; H, 6.41. Found: C,
60.84; H, 6.21.
(E)-5-P h en yl-1,3-p en ta d ien e (33). TBAF (2.50 mL, 1 m
in THF) was added to a stirred solution of 30a (493 mg, 1.25
mmol) in THF (18 mL) under argon at 25 °C. After 26 h, the
reaction mixture was taken up in pentane, washed with H2O
and brine, and passed through a short column of neutral
alumina in pentane. Evaporation of the solution under argon
1
gave 33 (101 mg, 56%). The H NMR and GC analyses of 33
agree with those of an authentic sample.
By the above procedure 30b (510 mg, 1.37 mmol) was
converted to 33 (124 mg, 63%). Similarly, 30c (497 mg, 1.39
1
mmol) yielded 33 (118 mg, 59%). The IR, H NMR, MS, and
GC properties of 33 obtained from 30b and 30c correspond to
those of a sample prepared previously.
Allylen ecyclobu ta n e (34, n ) 3). n-BuLi (1.00 mL, 2.70
M, 2.75 mmol) was added to 25 (0.50 g, 1.38 mmol) in
anhydrous THF (10 mL) at -78 °C under argon. Upon
addition of HMPA (2.0 g, 11.0 mmol) and 1,3-dichloropropane
(0.19 g, 1.67 mmol), the cooling bath was removed, and the
mixture was stirred for 1 h and then cooled (-78 °C).
Additional n-BuLi (0.50 mL, 1.38 mmol) was added, and the
clear yellow solution was allowed to warm to room tempera-
ture. After 1 h, the mixture was worked up as for 33 and
concentrated to a yellow clear oil. Column chromatography
(silica gel; ethyl acetate 0-6%) yielded 37 (0.28 g, 67%) as a
colorless oil: 1H NMR (CCl4) δ 0.00 (s, 9 H), 1.50 (d, J ) 7 Hz,
2 H), 1.6-2.1 (m, 2 H), 2.41 (s, 3 H), 2.6-3.0 (m, 2 H), 5.0-5.8
(m, 2 H), 7.25 (d, J ) 9 Hz, 2 H), 7.62 (d, J ) 9 Hz, 2 H); mass
spectrum, m/e calcd for
167.1256, found 167.1274.
C
10H19Si (M+ - p-CH3C6H4SO2)
Following the procedure used for preparing 33 from 30a ,
37 (0.28 g, 0.87 mmol) was converted to 34, n ) 3 (69 mg, 84%),
identical with a prior sample.12
Ack n ow led gm en t. We thank the National Science
Foundation for support of this research.
Su p p or tin g In for m a tion Ava ila ble: NMR spectra (27
pages). This material is contained in libraries on microfiche,
immediately follows this article in the microfilm version of the
journal, and can be ordered from the ACS; see any current
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J O970546C