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Regio- and stereoselective synthesis of allylsilanes using (methylphenylamino) tributylphosphonium iodine
Tetrahedron Letters,Vol.23,No.5,pp 557-560,1982 Printed in Great Britain
0040-4039/82/050557-04$03.00/O 01982 Pergamon Press Ltd.
REGIO- AND STEREOSELECTIVE SYNTHESIS OF ALLYLSILANES USING (METHYLPHENYLAMINO~TRIBUTYLPHOSPH~NIUM Yoshio Tanigawa,
*
IODIDE *
Yoshihide Fuse, and Shun-Ichi Murahashi
Department of Chemistry, Faculty of Engineering Science, Osaka University, Toyonaka, Osaka 560, Japan Regio- and stereoselective synthesis of variously substituted allylsilanes is achieved by organocuprate-mediated y-coupling of allylic alcohols using the title reagent (1). Recently, allylsilanes are recognized to be valuable synthetic intermediates
and a number of methods for the synthesis of allylsilanes have been
explored::Z.
However, the problem of regio- and stereocontrol still remains
except for some special cases.
Therefore, further development of highly regio-
and stereocontrolled means are required to reply to its synthetic potentiality. We now wish to report a new general method, which has the virtue of being applicable to the preparation of variously substituted allylsilanes. method is schematizedby
The
the transformation sequence as shown in eq 1. 1. CH3Li 2. GUI
OH
3. RLi (1) 4. "Bu3P+N(Me)Ph IR
2
3
(1, Rl=SiMe3 or R'=CH SiMe 2 3 The starting substrates, a-trimethylsilylmethy13
(2, R2=CH2SiMe3) and y-
trimethylsilyl(Z, Rl=SiMe3) substituted allylic alcohols4 (2) can be readily prepared in large quantities by conventional methods.
Therefore, the direct
alkylation of such alcohols (2) with organolithium compounds with the aid of (methylphenylamino)tributylphosphonium iodide (:I5 would give an efficient method for the synthesis of allylsilanes.
The full scope of the reaction is
summarized in the Table. This method has proven to be valuable in some aspects.
(1) The reaction (-70'Csroom temperature). (2) The reaction is quite general and various substituted allylsilanes are directly
can be accomplished under mild conditions
prepared from substrate 2 in moderate yields with high regio- (SN2' alkylation)
557
558
Synthesis
Table. with
Organolithium
Substrate
Entry
R1
of Allylsilanes
Compounds
(2)
R2 -
Me3Si
from the Reaction
Allylsilane
Organolithium Compound
(RLi)
Alcohols
(3)6reJf
(2)
Isolated
b
Yieldj'k(%)
Me3SiY-
n-BuLi
H
of Allylic
Using la
771
n-Bu
Ph
Me3Si
MeLi
70 Me3SiYPh CH3 4
n-Bu
Me3Si
PhLi
55 Me3siY 5 NMe2c
n-Bu
Me3Si
g
NMe2
50 &
SiMe3 67
5
Me3Si
CH=NC6Hll
n-Bu
d
h 49
Li
Me3SiCH2
H
76
n-BuLi n-BuMSiMe3 8
Me3SiCH2
H
53
PhLi PhmSiMe3i 9
Me3SiCH2
Ph
MeLi
75 PhTSiMe3 CH3
a All reactions described ' Prepared
_-
were performed on a 3-6 mm01 scale with the same procedure as b One equivalent of organolithium compound was used.
in the text.
by the literature:
K. P. Klein
and C. R. Hauser,
J. Org. Chem.,
32, -.,_
559
1479
d Prepared
(1967).
ibid ., 41, 1564
by the literature:
(1976).
e All
and elemental
products
spectral
means
by GLC.
g 7-Trimethylsilylundec-5-enell
llwas obtained __ chromatographic 2 were
in S-15%.
mmHg.
and stereoselectivity
(E-configuration
applicable
to various
organolithium
to an easy
and straightforward
Thus,
the introduction
of double
of 1-trimethylsilylhept-1-en-3-01
compounds
regio-
(entry 5).
solution
of the allyloxycopper
(0.932 g, 5 mmol), g, 5 mmol)
MeLi
in dry THF
sion of o-lithiated piperonal mmol)
piperonal
(30 mL)
shaking
was
and quenched
of the ethereal N-methylaniline
removed
silica
in vacua.
gel gave
the used
The mixture
extracts
with
Column
n-BuLi
by the treatment
suspension
of the lithium
a solution
(2.167 g, 5 mmol)
stirred aqueous
of 1
for 8 hr at -70°C NH4C1
the hydrolysis followed
solution
solution
in
to room
(O'C).
After
(40 mL x 4) to
of the imine,
the solvent
by preparative
tic on
yield
based
on
1:9, Rf 0.63).
using
alcohols
(2: R1,R2=H,
1 is an alternative
However,
alkyl,
attractive
the regioselectivity
method
of 1-phenylprop-2-en-l-01
trimethylsilyllithium
under
nitrogen
an 1:l mixture
gave
of allylic
alcohols
aryl)
for the
with
of 1-phenyl-3-
and 3,3-trimethylsilylphenylprop-1-ene
for the silylation
and/or
for the silylation
the treatment
Therefore,
of 6.3
of the o-lithiated
Thus,
yield.
(0.952
suspen-
(1.6 M in hexane,
is not satisfactory.
trimethylsilylprop-1-ene
iodide
by the transfer
chromatography
of allylic
of allylsilanes.
A green
an orange
allylsilane 8 (0.778 g, 49% isolated
EtOAc-hexane
silylation
and cuprous flask,
was prepared with
is represen-
N2 atmosphere.
1-trimethylsilylhept-1-en-3-01
2N HCl aqueous
and to complete
trimethylsilyllithium
synthesis
from
was
a saturated
o-lithiated
'-enyl)piperonal under
To an orange
was added
by the
4 and 5).
In a separate
was prepared
with
the desired
alcohol:
The direct with
at -7OOC.
into the ortho-
can be achieved
5.25 mmol),
cyclohexylimine
which
leads
allylsilanes.
the corresponding
performed
(1.388 g, 6 mmol)
(20 mL) at -70°C.
temperature
remove
at O°C.
to the allyloxycopper,
dry DMF
were
was prepared
(20 mL)
(allyloxy)arylcuprate, compound
(entries
(1.44 M in ether,
cyclohexylimine
in dry THF
with
of 2-(l'-trimethylsilylhept-2 All procedures
the reaction
group
and piperonal
and stereoselectively
is
functionalized
of l-trimethylsilylhept-2-enyl
of N,N-dimethylbenzylamine
(3) This method
Therefore,
to variously
reactions
The preparation
bond).
compounds.
access
positions
tative
and K. M. Fowler,
i E/Z=Z/l"Tby GLC). j Pure substances by column _ _ k (silica gel). In all reactions, starting alcohols 1 Isolated yield by Kugelrohr distillation, Tbath
separation
recovered
104“C/58
analyses.
in 6% yield.
F. E. Ziegler
have been fully characterized by f Isomeric purity is higher than 99% h was obtained in 10% yield. Compound
in 60% total
the Calas
method'
560
which involves the reductive silylation of 2-alkenyloxysilanes with chlorotrimethylsilane and lithium is much superior to the silylation using 1. Work is currently in progress on the application of this reaction to other synthesis of useful functionalized allylsilanes. References and Notes 1. For reviews, see: R. Calas, J. Organomet. Chem., 200, ll(1980); T. H. Chan _+.,_ and I. Fleming, Synthesis, 761(1979). . 2. (a) A. Hosomi, M. Saito, and H. Sakurai, Tetrahedron Lett., 355(1980); (b) idem, ibid., 429(1979); (c) A. Hosomi and H. Sakurai, ibid., 2589(1978); (d) A. Hosomi, A. Shirahata, and H. Sakurai, Chemistry Lett., 901(1978); (e) T. Hayashi, Y. Katsuro, and M. Kumada, Tetrahedron Lett., 3915(1980);
(f) H.
Yatagai, Y. Yamamoto, and K. Maruyama, J. Am. Chem. Sot., ___ 102, 4548(1980); (g) D. Seyferth, K. R. Wursthorn, T. F. 0. Lim, and D. J. Sepelak, J. Organomet. Chem., 181, mm- 293(1979); (h) I. Ojima and M. Kumagai, ibid ., 134, C6(1977). 3. 1,2-Addition of trimethylsilylmethylmagnesium chloride to a,B-unsaturated carbonyl compounds, see: M. J. Carter and I. Fleming, Chem. Comm., 679(1976). 4. Reduction of 3-trimethylsilylpropargylic alcohols with LiA1H4, see: G. Stork, M. E. Jung, E. Colvin, and Y. Noel, J. Am. Chem. Sot., 96, 3684(1974). -5. Y. Tanigawa, H. Ohta, A. Sonoda, and S.-I. Murahashi, ibid ., Ml~, 4610(1978). 6. The stereo&mu&q
of allylsilanes except for 4 was characterized by the 1 (JtransCHcCH, Hz) in the H NMR and by
coupling constant of olefinic protons
the out-of-plane deformation vibration of trans-disubstituted olefins
(cm-l) in the IR as follows: 5, 15 Hz, 963 cm-'; 6, 15, 965; 7, 16, 965; 8, 18, 965;
E-9, - .., 19, 965; 10, 5- 19, 963. E-Stereochemistry of 4 was determined by the similar pattern of olefinic protons in the 1H NMR -with that of reported allylsilanes 2g and by the IR as follows: 6 (chemical shift from Me3Si group -1 as 0.00 ppm) 6.10-6.27 (m, 2H), 965 cm . 7. TLC on silica gel, EtOAc-hexane 1:9, Rf 0.41.
NMR(CC14,6): O.OO(s, 9H), 0.91
(m, 3H), 1.15-1.60(m, 6H), 2.19(s, 6H), 3.48(d-d, 8, lHz, lH), 3.24(s, lH), 3.34(s, lH), 5.23(d-t-d, 15, 6, lHz, lH), 5.70(d-d-t, 15, 8, lHz, lH), 7.06 (s, 4H). 8. NMR(CC14,6): O.OO(s, 9H), 0.95(m, 3H), l.lO-1.60(m, 4H), 1.75-2.25(m, 2H), 4.58(d-d, 10, lHz, lH), 5.33(d-t-d, 16, 6, lHz, lH), 6.13(d-d-t, 16, 10, lHz, lH), 5.95(d, 2Hz, lH), 6.00(d, 2Hz, lH), 6.63(d, OHz, lH), 7.18(d, 8Hz, lH), 9.88(s, 1H). 9. C. Biran, J. Dunogues, R. Calas, J. Gerval, and T. Tskhovrebachvili, Synthesis, 220(1981). (Received in Japan 29 October 1981)
0040-4039/82/050557-04$03.00/O 01982 Pergamon Press Ltd.
REGIO- AND STEREOSELECTIVE SYNTHESIS OF ALLYLSILANES USING (METHYLPHENYLAMINO~TRIBUTYLPHOSPH~NIUM Yoshio Tanigawa,
*
IODIDE *
Yoshihide Fuse, and Shun-Ichi Murahashi
Department of Chemistry, Faculty of Engineering Science, Osaka University, Toyonaka, Osaka 560, Japan Regio- and stereoselective synthesis of variously substituted allylsilanes is achieved by organocuprate-mediated y-coupling of allylic alcohols using the title reagent (1). Recently, allylsilanes are recognized to be valuable synthetic intermediates
and a number of methods for the synthesis of allylsilanes have been
explored::Z.
However, the problem of regio- and stereocontrol still remains
except for some special cases.
Therefore, further development of highly regio-
and stereocontrolled means are required to reply to its synthetic potentiality. We now wish to report a new general method, which has the virtue of being applicable to the preparation of variously substituted allylsilanes. method is schematizedby
The
the transformation sequence as shown in eq 1. 1. CH3Li 2. GUI
OH
3. RLi (1) 4. "Bu3P+N(Me)Ph IR
2
3
(1, Rl=SiMe3 or R'=CH SiMe 2 3 The starting substrates, a-trimethylsilylmethy13
(2, R2=CH2SiMe3) and y-
trimethylsilyl(Z, Rl=SiMe3) substituted allylic alcohols4 (2) can be readily prepared in large quantities by conventional methods.
Therefore, the direct
alkylation of such alcohols (2) with organolithium compounds with the aid of (methylphenylamino)tributylphosphonium iodide (:I5 would give an efficient method for the synthesis of allylsilanes.
The full scope of the reaction is
summarized in the Table. This method has proven to be valuable in some aspects.
(1) The reaction (-70'Csroom temperature). (2) The reaction is quite general and various substituted allylsilanes are directly
can be accomplished under mild conditions
prepared from substrate 2 in moderate yields with high regio- (SN2' alkylation)
557
558
Synthesis
Table. with
Organolithium
Substrate
Entry
R1
of Allylsilanes
Compounds
(2)
R2 -
Me3Si
from the Reaction
Allylsilane
Organolithium Compound
(RLi)
Alcohols
(3)6reJf
(2)
Isolated
b
Yieldj'k(%)
Me3SiY-
n-BuLi
H
of Allylic
Using la
771
n-Bu
Ph
Me3Si
MeLi
70 Me3SiYPh CH3 4
n-Bu
Me3Si
PhLi
55 Me3siY 5 NMe2c
n-Bu
Me3Si
g
NMe2
50 &
SiMe3 67
5
Me3Si
CH=NC6Hll
n-Bu
d
h 49
Li
Me3SiCH2
H
76
n-BuLi n-BuMSiMe3 8
Me3SiCH2
H
53
PhLi PhmSiMe3i 9
Me3SiCH2
Ph
MeLi
75 PhTSiMe3 CH3
a All reactions described ' Prepared
_-
were performed on a 3-6 mm01 scale with the same procedure as b One equivalent of organolithium compound was used.
in the text.
by the literature:
K. P. Klein
and C. R. Hauser,
J. Org. Chem.,
32, -.,_
559
1479
d Prepared
(1967).
ibid ., 41, 1564
by the literature:
(1976).
e All
and elemental
products
spectral
means
by GLC.
g 7-Trimethylsilylundec-5-enell
llwas obtained __ chromatographic 2 were
in S-15%.
mmHg.
and stereoselectivity
(E-configuration
applicable
to various
organolithium
to an easy
and straightforward
Thus,
the introduction
of double
of 1-trimethylsilylhept-1-en-3-01
compounds
regio-
(entry 5).
solution
of the allyloxycopper
(0.932 g, 5 mmol), g, 5 mmol)
MeLi
in dry THF
sion of o-lithiated piperonal mmol)
piperonal
(30 mL)
shaking
was
and quenched
of the ethereal N-methylaniline
removed
silica
in vacua.
gel gave
the used
The mixture
extracts
with
Column
n-BuLi
by the treatment
suspension
of the lithium
a solution
(2.167 g, 5 mmol)
stirred aqueous
of 1
for 8 hr at -70°C NH4C1
the hydrolysis followed
solution
solution
in
to room
(O'C).
After
(40 mL x 4) to
of the imine,
the solvent
by preparative
tic on
yield
based
on
1:9, Rf 0.63).
using
alcohols
(2: R1,R2=H,
1 is an alternative
However,
alkyl,
attractive
the regioselectivity
method
of 1-phenylprop-2-en-l-01
trimethylsilyllithium
under
nitrogen
an 1:l mixture
gave
of allylic
alcohols
aryl)
for the
with
of 1-phenyl-3-
and 3,3-trimethylsilylphenylprop-1-ene
for the silylation
and/or
for the silylation
the treatment
Therefore,
of 6.3
of the o-lithiated
Thus,
yield.
(0.952
suspen-
(1.6 M in hexane,
is not satisfactory.
trimethylsilylprop-1-ene
iodide
by the transfer
chromatography
of allylic
of allylsilanes.
A green
an orange
allylsilane 8 (0.778 g, 49% isolated
EtOAc-hexane
silylation
and cuprous flask,
was prepared with
is represen-
N2 atmosphere.
1-trimethylsilylhept-1-en-3-01
2N HCl aqueous
and to complete
trimethylsilyllithium
synthesis
from
was
a saturated
o-lithiated
'-enyl)piperonal under
To an orange
was added
by the
4 and 5).
In a separate
was prepared
with
the desired
alcohol:
The direct with
at -7OOC.
into the ortho-
can be achieved
5.25 mmol),
cyclohexylimine
which
leads
allylsilanes.
the corresponding
performed
(1.388 g, 6 mmol)
(20 mL) at -70°C.
temperature
remove
at O°C.
to the allyloxycopper,
dry DMF
were
was prepared
(20 mL)
(allyloxy)arylcuprate, compound
(entries
(1.44 M in ether,
cyclohexylimine
in dry THF
with
of 2-(l'-trimethylsilylhept-2 All procedures
the reaction
group
and piperonal
and stereoselectively
is
functionalized
of l-trimethylsilylhept-2-enyl
of N,N-dimethylbenzylamine
(3) This method
Therefore,
to variously
reactions
The preparation
bond).
compounds.
access
positions
tative
and K. M. Fowler,
i E/Z=Z/l"Tby GLC). j Pure substances by column _ _ k (silica gel). In all reactions, starting alcohols 1 Isolated yield by Kugelrohr distillation, Tbath
separation
recovered
104“C/58
analyses.
in 6% yield.
F. E. Ziegler
have been fully characterized by f Isomeric purity is higher than 99% h was obtained in 10% yield. Compound
in 60% total
the Calas
method'
560
which involves the reductive silylation of 2-alkenyloxysilanes with chlorotrimethylsilane and lithium is much superior to the silylation using 1. Work is currently in progress on the application of this reaction to other synthesis of useful functionalized allylsilanes. References and Notes 1. For reviews, see: R. Calas, J. Organomet. Chem., 200, ll(1980); T. H. Chan _+.,_ and I. Fleming, Synthesis, 761(1979). . 2. (a) A. Hosomi, M. Saito, and H. Sakurai, Tetrahedron Lett., 355(1980); (b) idem, ibid., 429(1979); (c) A. Hosomi and H. Sakurai, ibid., 2589(1978); (d) A. Hosomi, A. Shirahata, and H. Sakurai, Chemistry Lett., 901(1978); (e) T. Hayashi, Y. Katsuro, and M. Kumada, Tetrahedron Lett., 3915(1980);
(f) H.
Yatagai, Y. Yamamoto, and K. Maruyama, J. Am. Chem. Sot., ___ 102, 4548(1980); (g) D. Seyferth, K. R. Wursthorn, T. F. 0. Lim, and D. J. Sepelak, J. Organomet. Chem., 181, mm- 293(1979); (h) I. Ojima and M. Kumagai, ibid ., 134, C6(1977). 3. 1,2-Addition of trimethylsilylmethylmagnesium chloride to a,B-unsaturated carbonyl compounds, see: M. J. Carter and I. Fleming, Chem. Comm., 679(1976). 4. Reduction of 3-trimethylsilylpropargylic alcohols with LiA1H4, see: G. Stork, M. E. Jung, E. Colvin, and Y. Noel, J. Am. Chem. Sot., 96, 3684(1974). -5. Y. Tanigawa, H. Ohta, A. Sonoda, and S.-I. Murahashi, ibid ., Ml~, 4610(1978). 6. The stereo&mu&q
of allylsilanes except for 4 was characterized by the 1 (JtransCHcCH, Hz) in the H NMR and by
coupling constant of olefinic protons
the out-of-plane deformation vibration of trans-disubstituted olefins
(cm-l) in the IR as follows: 5, 15 Hz, 963 cm-'; 6, 15, 965; 7, 16, 965; 8, 18, 965;
E-9, - .., 19, 965; 10, 5- 19, 963. E-Stereochemistry of 4 was determined by the similar pattern of olefinic protons in the 1H NMR -with that of reported allylsilanes 2g and by the IR as follows: 6 (chemical shift from Me3Si group -1 as 0.00 ppm) 6.10-6.27 (m, 2H), 965 cm . 7. TLC on silica gel, EtOAc-hexane 1:9, Rf 0.41.
NMR(CC14,6): O.OO(s, 9H), 0.91
(m, 3H), 1.15-1.60(m, 6H), 2.19(s, 6H), 3.48(d-d, 8, lHz, lH), 3.24(s, lH), 3.34(s, lH), 5.23(d-t-d, 15, 6, lHz, lH), 5.70(d-d-t, 15, 8, lHz, lH), 7.06 (s, 4H). 8. NMR(CC14,6): O.OO(s, 9H), 0.95(m, 3H), l.lO-1.60(m, 4H), 1.75-2.25(m, 2H), 4.58(d-d, 10, lHz, lH), 5.33(d-t-d, 16, 6, lHz, lH), 6.13(d-d-t, 16, 10, lHz, lH), 5.95(d, 2Hz, lH), 6.00(d, 2Hz, lH), 6.63(d, OHz, lH), 7.18(d, 8Hz, lH), 9.88(s, 1H). 9. C. Biran, J. Dunogues, R. Calas, J. Gerval, and T. Tskhovrebachvili, Synthesis, 220(1981). (Received in Japan 29 October 1981)