Mesoporous aluminosilicate-catalyzed allylation of carbonyl compounds and acetals

Article abstract of DOI:10.1016/j.tet.2011.01.055

A mesoporous aluminosilicate (Al-MCM-41) was found to be an effective heterogeneous catalyst for the reaction of both carbonyl compounds and acetals with allylsilanes to afford the corresponding homoallyl silyl ethers and homoallyl alkyl ethers, respectively. Both the mesoporous structure and the presence of aluminum moiety were indispensable for the high catalytic activity of Al-MCM-41. Moreover, Al-MCM-41 could catalyze the reaction of acetals chemoselectively in the presence of the corresponding carbonyl compounds. The solid acid catalyst Al-MCM-41 could be recovered easily by filtration and could be reused three times without a significant loss of catalytic activity.

Full text of DOI:10.1016/j.tet.2011.01.055

Tetrahedron 67 (2011) 2081e2089
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Mesoporous aluminosilicate-catalyzed allylation of carbonyl compounds
and acetals
*
Suguru Ito, Akira Hayashi, Hirotomo Komai, Hitoshi Yamaguchi, Yoshihiro Kubota, Masatoshi Asami
Department of Advanced Materials Chemistry, Graduate School of Engineering, Yokohama National University, Tokiwadai 79-5, Hodogaya-ku, Yokohama 240-8501, Japan
a r t i c l e i n f o
a b s t r a c t
Article history:
A mesoporous aluminosilicate (Al-MCM-41) was found to be an effective heterogeneous catalyst for the
reaction of both carbonyl compounds and acetals with allylsilanes to afford the corresponding homoallyl
silyl ethers and homoallyl alkyl ethers, respectively. Both the mesoporous structure and the presence of
aluminum moiety were indispensable for the high catalytic activity of Al-MCM-41. Moreover, Al-MCM-41
could catalyze the reaction of acetals chemoselectively in the presence of the corresponding carbonyl
compounds. The solid acid catalyst Al-MCM-41 could be recovered easily by filtration and could be
reused three times without a significant loss of catalytic activity.
Received 19 October 2010
Received in revised form 18 January 2011
Accepted 18 January 2011
Available online 25 January 2011
Keywords:
Al-MCM-41
Solid acid catalyst
Allylation
Ó 2011 Elsevier Ltd. All rights reserved.
Homoallyl silyl ether
Homoallyl alkyl ether
1. Introduction
a
aqueous
OH
β
O
O
quenching
Lewis acid
Al-MCM-41
β
Among the wide variety of carbonecarbon bond-forming re-
actions, Lewis acid-promoted allylations of aldehydes, ketones, and
acetals with allylsilanes to afford homoallyl alcohol derivatives
(Sakurai allylation) are valuablereactions inorganicsynthesis because
of the high synthetic utility of the products. The new carbonecarbon
Si
+
+
R
R
R'
R'
γ
α
γ
desilylated product
α
R'
waste water,
inorganic salts
b
OSi
bond is formed regioselectively at g-carbon of allylsilanes (Scheme
filtration
Si
1a). Usually, stoichiometric or sub-stoichiometric amounts of strong
Lewis acids (e.g., TiCl4, BF3$OEt2, and AlCl3) are required to promote
the reaction because a tight coordination of the product to the Lewis
acid results inpoor turnover of the acid.1 Catalytic Sakurai allylation2,3
was also investigated and many kinds of catalysts, such as Sc
(OTf)3,2a,b,3f Yb(OTf)3,2c iodine,2d and FeCl3,2e,3d have been found to
date. However, the catalyst recycling is generally difficult in such ho-
mogeneous systems because the catalystdecomposes during aqueous
workup, and the desilylated product is produced along with waste
water and inorganic salts.
From an environmental and economical point of view, the
development of heterogeneous organic reaction systems catalyzed
by solid acid catalysts is important in the field of synthetic
organic chemistry, recently.4 Solid acids do not require an aqueous
quenchingand theycould berecoveredeasily from a reactionmixture
generally. Although metal cations-exchanged or proton-exchanged
R
R
R'
homoallyl silyl ether
Al-MCM-41
(recovery)
Si = trialkyl silyl group
Scheme 1. Sakurai allylation of carbonyl compounds (a) promoted by a conventional
Lewis acid and (b) catalyzed by Al-MCM-41.
montmorillonites5,6 and rare earth metals-exchanged zeolite-Y7 have
been reported as effective solid acid catalysts for Sakurai allylation,
thesecatalyticsystemssometimeshavedisadvantages, suchashigher
reaction temperature or low yields of the allylated products.
On the other hand, mesoporous silicate MCM-41 and modified
MCM-41s have become useful heterogeneous catalysts for wide va-
riety of reactions due to its ordered pore structure, uniform pore di-
ameter (2e10 nm), and high-surface area (>1000 m2/g).8 Moreover,
it is well known that catalytic activity of MCM-41 increases by in-
corporating aluminum into its structure.4b Aluminum incorporated
MCM-41 (Al-MCM-41) shows remarkable acidic properties, and has
been found to catalyze several organic transformations under vapor
* Corresponding author. Tel./fax: þ81 45 339 3968; e-mail address: m-asami@
ynu.ac.jp (M. Asami).
0040-4020/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2011.01.055

2082
S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
phase or high-temperature reaction conditions.9aee Furthermore, Al-
MCM-41 could catalyze liquid-phase reactions under mild reaction
conditions.9fei In our preliminary communication, Al-MCM-41 was
found to catalyze the allylation of aldehydes with allylsilanes under
mild reaction conditions to afford the corresponding homoallyl silyl
ether (Scheme 1b).10a The reaction of acetals was also catalyzed by Al-
MCM-41.10b Herein, we describe the details of the Al-MCM-41-cata-
lyzed allylation of aldehydes, ketones, and acetals with allylsilanes.
Table 2
Allylation of benzaldehyde with allyltrimethylsilane in the presence of various silica
catalysts
O
OSiMe3
Catalyst
SiMe3
+
CH2Cl2 (0.5 M)
15 °C, 2.5 h
Ph
1a
(1.0 mmol)
H
Ph
2
3a
(1.5 mmol)
Entry
Catalyst (Si/Al)
Surface area (m2/g)
Amount (mg)
Yielda(%)
2. Results and discussion
1
2
3
4
Al-MCM-41 (26)
JRC-SAH-1 (2)
JRC-SAL-2 (5)
SiO2/Al2O3 (31)
MCM-41 (N)
SBA-15 (N)
1120
610
570
385
1080
925
30
55
59
87
30
30
30
93
N.R.
N.R.
N.R.
N.R.
N.R.
92
According to a known procedure with slight modification,11 Al-
MCM-41s (Si/Al¼23, 26, 34, and 48) were synthesized from
cethyltrimethylammonium bromide, tetramethylammonium hy-
droxide, aluminum triisopropoxide, and tetraethyl orthosilicate.
To begin with, the effect of solvent was examined for the re-
action of benzaldehyde (1a) (1.0 mmol) with allyltrimethylsilane
(2) (1.5 mmol) in the presence of Al-MCM-41 (30 mg, Si/Al¼26,
dried prior to use at 120 ꢀC for 1 h under vacuum). The best result
was obtained when the reaction was carried out in dichloro-
methane at 15 ꢀC for 2.5 h. After the reaction, the catalyst was re-
moved by filtration. The filtrate was then concentrated and purified
by silica-gel column chromatography to afford the corresponding
homoallyl alcohol derivative 3a in 93% yield. It should be noted that
the product was obtained as trimethylsilyl ether because an
aqueous workup is unnecessary (Table 1, entry 1). The use of tol-
uene or nitromethane as a solvent also afforded the homoallyl silyl
ether in good yields (entries 2 and 3). In contrast, the reaction did
not take place in ether, THF, cyclohexane, or hexane (entries 4e7).
Next, to examine the effect of the mesoporous structure and
presence of aluminum moiety, the reaction was carried out using
various silica catalysts in place of Al-MCM-41 (Table 2). In the
presence of amorphous silica/aluminas (JRC-SAH-1, JRC-SAL-2, and
SiO2/Al2O3), the reaction did not take place even though larger
amount of catalysts were used to make the surface areas same
(entries 2e4). Furthermore, aluminum-free mesoporous silicates
(MCM-41 and SBA-15) could not catalyze the reaction (entries 5
and 6). These results suggest that the high catalytic activity of Al-
MCM-41 is originated from the presence of both mesoporous
structure and aluminum moiety in the catalyst. The superiority of
Al-MCM-41 over amorphous silica/alumina is probably due to more
efficient interaction between organic substrate and solid surface
caused by concentration effect inside the ordered, hydrophobic
mesopores with high-surface area. When the reaction was per-
formed in dichloromethane at 30 ꢀC, the reaction was completed in
1 h and the corresponding homoallyl silyl ether 3a was obtained in
92% yield (entry 7).
5
6
7b
Al-MCM-41 (26)
1120
a
Isolated yield after column chromatography.
Reaction was performed at 30 ꢀC for 1 h.
b
The Al-MCM-41-catalyzed allylation was then applied to the re-
action of various aldehydes with allyltrimethylsilane (Table 3).
Electron-withdrawing groups (NOꢁ2 , Brꢁ, and Clꢁ) on the aromatic
ringaccelerated the reaction, and the reactionwas completed within
30 min to afford the corresponding homoallyl silyl ether in excellent
yields (entries 1e6). Aromatic aldehydes bearing electron-donating
groups were less reactive than benzaldehyde. The reaction of o-, m-,
and p-tolualdehyde gave the allylated products in moderate to good
yields (entries 7e10). When o- and m-anisaldehyde were used, the
desired products were obtained in moderate yields (entries 12 and
13), whereas p-anisaldehyde gave only trace amount of the product
(entry 11). In the case of naphthaldehydes, corresponding homoallyl
silyl ethers were obtained in good yields although the reactivities
Table 3
Allylation of various aldehydes with allyltrimethylsilane catalyzed by Al-MCM-41
Al-MCM-41
(30 mg, Si/Al = 26)
O
OSiMe3
SiMe3
+
CH2Cl2 (0.5 M)
30 °C, 0.5-2.5 h
R
H
R
1
2
3
(1.0 mmol)
(1.5 mmol)
Entry
R
Time (h)
Yielda(%)
1
2
3
4
5
6
4-NO2C6H4
4-BrC6H4
4-ClC6H4
2-NO2C6H4
2-BrC6H4
2-ClC6H4
4-MeC6H4
4-MeC6H4
3-MeC6H4
2-MeC6H4
4-MeOC6H4
3-MeOC6H4
2-MeOC6H4
2-Naphthyl
2-Naphthyl
1-Naphthyl
1-Naphthyl
PhCH2CH2
PhCH2CH2
c-C6H11
0.5
0.5
0.5
0.5
0.5
0.5
1
2.5
1
1
1
1
1
1
1
1
1
1
92
97
93
90
95
93
27
59
70
83
<3
24
41
70
74
61
67
7
8b
9
Table 1
Allylation of benzaldehyde with allyltrimethylsilane catalyzed by Al-MCM-41
10
11
12
13
14
15b
16
17b
18
19b
20
21b
22
23
Al-MCM-41
O
OSiMe3
(30 mg, Si/Al = 26)
SiMe3
+
Ph
1a
H
solvent (0.5 M)
15 °C, 2.5 h
Ph
2
3a
(1.0 mmol)
(1.5 mmol)
26c (20)d
60c (48)d
54c (44)d
86c (73)d
85
Entry
Solvent
Yielda(%)
1
1
1
1
1
2
3
4
5
6
7
CH2Cl2
Toluene
MeNO2
Et2O
THF
Cyclohexane
Hexane
93
87
85
N.R.
N.R.
N.R.
N.R.
c-C6H11
t-Bu
(E)-PhCH]CH
1
7
a
Isolated yield after column chromatography unless otherwise noted.
Al-MCM-41 (50 mg) was used.
b
c
Determined by 1H NMR analysis using nitromethane as an internal standard.
Isolated yield of the corresponding homoallyl alcohol after hydrolysis.
a
d
Isolated yield after column chromatography.

S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
2083
Table 5
were slightly lower than that of benzaldehyde (entries 14e17). Al-
Allylation of various acetals with allyltrimethylsilane catalyzed by Al-MCM-41
though aromatic aldehydes, especially electron-rich aromatic alde-
hydes, are often diallylated by Lewis acid-catalyzed allylation with
allylsilanes because of the stability of benzylic cation,2b,e the dia-
llylated product was not detected in this catalytic system. The re-
action of aliphatic aldehydes was also examined. In the case of
3-phenylpropanal and cyclohexanecarboxaldehyde, the formation
of the corresponding silyl enol ethers12 caused the decrease in the
yield of the allylated products (entries 18 and 20). The yields were
improved by increasing the amount of the catalyst (entries 19 and
21). The allylated products of these reactions were isolated after
hydrolysis of the silyl ethers because the homoallyl silyl ether and
the silyl enol ether were hard to separate by silica-gel column
chromatography. Pivalaldehyde was allylated in 85% yield despite its
steric hindrance (entry 22). The reaction did not proceed well with
Al-MCM-41
OMe
OMe
4
OMe
(30 mg, Si/Al = 48)
SiMe3
+
CH2Cl2 (0.5 M)
30 °C, 45 min
R
R
2
5
(1.5 mmol)
(1.0 mmol)
Entry
R
Yielda(%)
1
2
3
4
5
6
7
8
Ph
93
98
90
92
96
86
92
93
92
95
76
88
89
80
74
93
93
85
4-NO2C6H4
4-BrC6H4
2-BrC6H4
4-ClC6H4
3-ClC6H4
2-ClC6H4
4-MeC6H4
3-MeC6H4
2-MeC6H4
4-MeOC6H4
2-MeOC6H4
2-Naphthyl
1-Naphthyl
(E)-PhCH]CH
c-C6H11
a,b-unsaturated aldehyde, and the 1,2-adduct was obtained in 7%
yield from (E)-cinnamaldehyde (entry 23).
9
10
11b
12
13
14
15
16
17
18c
As good results were obtained in the reaction of aldehydes, Al-
MCM-41-catalyzed allylation of acetals was examined (Table 4). In
the presence of Al-MCM-41 (30 mg, Si/Al¼26), the reaction of
benzaldehyde dimethyl acetal (4a) (1.0 mmol) with 2 (1.5 mmol) in
dichloromethane at 30 ꢀC for 45 min afforded 4-methoxy-4-phe-
nylbut-1-ene (5a) in 86% yield along with 7% yield of 1-phenylbuta-
1,3-diene (6) (entry 1). The reaction did not occur in the presence of
SiO2/Al2O3 or MCM-41 as was observed in the case of allylation of
aldehydes (entries 2 and 3).13 By reducing the aluminum content of
the catalyst, the amount of 6 produced in the reaction decreased
and only 5a was obtained in 96% yield by using Al-MCM-41 (Si/
Al¼48) (entries 4 and 5).
PhCH2CH2
Ph
a
Isolated yield.
Allyltrimethylsilane (3.0 mmol) was used.
Benzaldehyde diethyl acetal was used.
b
c
Al-MCM-41
O
O
OSiMe 3
(30 mg, Si/Al = 48)
Table 4
SiMe 3
+
Allylation of benzaldehyde dimethyl acetal with allyltrimethylsilane
Ph
O
Ph
CH2Cl2 (0.5 M)
30 °C, 2 h
OMe
8
7
2
(1.0 mmol)
1M aq. HCl
MeOH, rt, 0.5 h CH2Cl2, rt, 14 h MeOH, rt, 14 h Ph
(3.0 mmol)
Ph
Ph
Catalyst (30 mg)
OMe
OMe
4a
5a
OH
SiMe3
PDC, MS 4A
10 M KOH
+
+
Ph
CH2Cl2 (0.5 M)
30 °C, 45 min
2
9 85% (from 7)
6
(1.0 mmol)
(1.5 mmol)
Scheme 2. Synthesis of 1-phenylbut-3-en-1-ol from 2-phenyl-1,3-dioxane.
Entry
Catalyst
Si/Al
5aa(%)
6a(%)
1
2
3
4
5
Al-MCM-41
SiO2eAl2O3
MCM-41
Al-MCM-41
Al-MCM-41
26
31
N
86
0
0
91
96
7
0
0
4
carbonyl carbon. The reaction of ketones and ketals with allyl-
trimethylsilane was carried out in the presence of Al-MCM-41 (Si/
Al¼23 for ketones, Si/Al¼48 for ketals). The results are summarized
in Table 6. The reaction of cyclohexanone with 3.0 equiv of allyl-
trimethylsilane gave the corresponding homoallyl silyl ether in 89%
yield (entry 1). A ketal, cyclohexanone dimethyl ketal, afforded the
allylated product in 95% yield (entry 2). Allylation of 4-methyl-
cyclohexanone and 4-tert-butylcyclohexanone proceeded prefer-
entially from the equatorial direction and the allylated products
were obtained in high yields (entries 3 and 4). Dimethyl ketal of
4-tert-butylcyclohexanone also allylated successfully and the di-
astereomeric ratio was almost the same as the result of 4-tert-
butylcyclohexanone (entry 5). Allylation of acyclic dialkyl ketones
were also examined (entries 6, 7, and 9). The formation of the
corresponding self aldol product decreased the yields of the ally-
lated products in the case of alkyl methyl ketones (entries 7 and 9).
Dimethyl ketals of benzylacetone and 2-octanone were less re-
active even by using larger amount of the catalyst, and the yields of
the allylated products were 41% and 33%, respectively (entries 8 and
10). The reaction of acetophenone gave the allylated product in 18%
yield along with the corresponding self aldol product in 33% yield
(entry 11). Allylation of propiophenone afforded the corresponding
homoallyl silyl ether in 23% yield, and the silyl enol ether of pro-
piophenone, (Z)-1-phenyl-1-trimethylsiloxypropene, was obtained
34
48
Trace
a
Determined by 1H NMR analysis of the crude product using nitromethane as an
internal standard.
In the presence of Al-MCM-41 (Si/Al¼48), various dimethyl ac-
etals were allylated effectively to afford the corresponding homo-
allyl methyl ethers (Table 5, entries 1e17). It should be noted that
the yield of the allylated products was increased in most cases
compared to the result of the corresponding aldehydes. Benzalde-
hyde diethyl acetal was allylated as well, and the corresponding
homoallyl ethyl ether was obtained in 85% yield (entry 18).
From a synthetic point of view, allylation of cyclic acetals
obtained from the corresponding aldehydes with 1,3-propanediol
is useful since the conversion of homoallyl 3-hydroxypropyl ethers
to the corresponding homoallyl alcohols is easier than that of
homoallyl alkyl ethers.14 As shown in Scheme 2, the reaction of 2-
phenyl-1,3-dioxane (7) with 2 in dichloromethane at 30 ꢀC for 2 h
gave homoallyl 3-(trimethylsiloxy)propyl ether 8. Desilylation fol-
lowed by oxidation and b-elimination gave 1-phenylbut-3-en-1-ol
(9) in 85% yield from 7.
The allylation of ketones is more difficult than that of aldehydes
usually due to the steric hindrance and electron density of their

2084
S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
Table 6
in 63% yield (entry 12). The formation of the self aldol adduct could
be explained as shown in Scheme 3. Initially, Al-MCM-41 promotes
the formation of the silyl enol ether A from enolizable ketone and
allyltrimethylsilane. When R0 was hydrogen, Al-MCM-41-catalyzed
self aldol reaction of A with another molecule of the ketone oc-
Allylation of various ketones and ketals with allyltrimethylsilane catalyzed by Al-
MCM-41a
Entry
1
Substrate
Time (h)
1.5
Product
OSiMe3
Yieldb(%)
89
O
curred to give b
-siloxy ketone B (entries 7, 9, and 11). When R0 was
methyl group, silyl enol ether A was isolated (entry 12). This is
probably because the higher steric hindrance inhibited the self al-
dol reaction. Methyl benzoylformate was allylated in toluene at
60 ꢀC for 24 h to give the desired product in 86% yield (entry 13).
OMe
OMe
OMe
2
3
1.5
2
95
79
OSiMe3
dr = 59:20c
OSiMe3
O
Me
O
Me
Me3SiO
O
OSiMe 3
R'
R'
Al-MCM-41
Al-MCM-41
O
R
R
R
+
R
R'
R'
SiMe3
R'
A
B
R
O
t
4
5
2
2
Bu
80
77
74
t
Bu
dr = 66:14c
Scheme 3. Self aldol reaction of ketones catalyzed by Al-MCM-41.
OMe
OMe
OMe
To estimate the chemoselectivity of Al-MCM-41-catalyzed ally-
lation, the reaction of benzaldehyde (1.0 mmol) and its dimethyl
acetal (1.0 mmol) with 1.1 equiv of 2 was carried out under the
same reaction conditions given in Table 5. Only the acetal reacted
with 2 to afford the corresponding homoallyl methyl ether in 92%
yield, and the allylated product of benzaldehyde was not obtained
(Table 7, entry 1). Moreover, all acetals and a ketal examined in
entries 2e7 were also allylated chemoselectively in the presence of
the corresponding carbonyl compounds, although the yield of the
products was affected by the reactivity of the substrates. With
regard to the chemoselectivity of the reaction, typical strong Lewis
acids (e.g., TiCl4, BF3$OEt2, and AlCl3) are known to show poor
chemoselectivity.15 Among the catalysts that activate both carbonyl
compounds and acetals in Sakurai allylation, no catalyst has been
reported to exhibit high acetal selectivity in the reaction, to the best
of our knowledge. High acetal selectivity achieved by Al-MCM-41
may be attributed to the preferential adsorption of acetals on the
surface of Al-MCM-41. Adsorbed acetals should be irreversibly
allylated since the reaction affords methoxytrimethylsilane as
a thermodynamically stable by-product.16
t
Bu
t
Bu
dr = 66:11c
O
6d
2
2
Me3SiO
O
67
Me3SiO
Ph
7
(16)e
Ph
MeO OMe
MeO
Ph
8f
24
41
Ph
O
40
Me3SiO
9
2
(39)e
n
n
C6H13
C6H13
The reaction of aldehydes with other silanes was then examined.
Bulkier silyl ethers are often useful than trimethylsilyl ether as
protective groups of alcohols. Allyltriethylsilane, allyltert-butyldi-
methylsilane, and allyltert-butyldiphenylsilane were synthesized
MeO OMe
C6H13
MeO
10f
11
24
24
33
n
n
C6H13
O
18
Me3SiO
Ph
(33)e
Table 7
Ph
Chemoselective allylation of acetals in the presence of carbonyl compounds
OSiMe3
R1
O
23
12
24
24
R2
Me3SiO
Ph
Al-MCM-41
(63)g
3 NDa
Ph
O
(30 mg, Si/Al = 48)
MeO OMe
R1 R2
4
SiMe3
+
+
+
R1 R2
1
OMe
CH2Cl2 (0.5 M)
30 °C, 45 min
R1
2
O
Me3SiO
Ph
R2
(1.0 mmol)
(1.1 mmol)
(1.0 mmol)
13h
86
OMe
OMe
Ph
5
O
O
Entry
R1
R2
Yield of 5b (%)
a
In the presence of Al-MCM-41 (30 mg, Si/Al¼23 and 48 were used for ketones
1
2
3
4
5
6
7
Ph
4-BrC6H4
4-MeC6H4
2-Naphthyl
(E)-PhCH]CH
PhCH2CH2
e(CH2)5e
H
H
H
H
H
H
92
96
94
79
49
61
29
and ketals, respectively), the reaction of
a substrate (1.0 mmol) with allyl-
trimethylsilane (3.0 mmol) was carried out in dichloromethane (0.5 M) at 30 ꢀC.
b
Isolated yield after column chromatography.
Isolated yield of each diastereomers. The structure of major isomer is shown.
Allyltrimethylsilane (5.0 equiv) was used.
Isolated yield of the corresponding self aldol adduct.
Al-MCM-41 (50 mg) was used.
Isolated yield of (Z)-1-phenyl-1-trimethylsiloxypropene.
Reaction was carried out in toluene (0.5 M) at 60 ꢀC.
c
d
e
f
g
a
Not detected.
h
Based on 4. Determined by 1H NMR analysis using nitromethane as an internal
b
standard.

S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
2085
from the corresponding silyl chloride and allylmagnesium chloride
in refluxing THF.17e19 The reaction of 4-nitrobenzaldehyde with
allyltriethylsilane or allyltert-butyldimethylsilane under the same
reaction conditions given in Table 3 afforded the corresponding
homoallyl silyl ethers in 93% and 91% yields, respectively (Table 8,
57% yield by using increased amount of the catalyst (entry 3).
Benzaldehyde and pivalaldehyde were also allylated with allyltert-
butyldimethylsilane in 86% and 87% yields, respectively (entries
4 and 5).
Substitutedallylsilanes, methallyltrimethylsilane, crotyltrimethyl-
silane, and trimethylprenylsilane, were synthesized according to the
literature procedure20e22 and their reactivity was examined in the
reaction with benzaldehyde (Table 9). The reaction of benzaldehyde
with methallyltrimethylsilane was completed in 1 h under the same
reaction conditions given inTable 3 to give the corresponding product
in 89% yield (entry 1), whereas crotyltrimethylsilane did not react
under the reaction conditions (entry 2). When the reaction was car-
ried out in toluene at 60 ꢀC, the addition of crotylsilane to benzalde-
Table 8
Allylation of aldehydes with various allylsilanes catalyzed by Al-MCM-41
Al-MCM-41
O
OSi
(30 mg, Si/Al = 26)
Si
+
CH2Cl2 (0.5 M), 30 °C
R
H
R
1
10
11
hyde occurred at g-position of the silane to afford the corresponding
(1.0 mmol) (1.5 mmol)
adduct in 35% yield as a diastereomer mixture (syn/anti¼1:1) (entry
3). The yield was increased to 47% by using a larger amount of catalyst
Entry
R
Sia
Time (h)
Yieldb(%)
(entry 4), and the
g-adduct was obtained in 88% yield by using
1
4-NO2C6H4
4-NO2C6H4
4-NO2C6H4
Ph
TES
0.5
0.5
0.5
1
93
91
57
86
87
2.0 equiv of crotylsilane (entry 5). The reaction of benzaldehyde with
prenylsilane under the same reaction conditions used in entry 5
2
TBDMS
TBDPS
TBDMS
TBDMS
3c
4
afforded the g-adductin13% yield(entry6). Theproductwasobtained
in 58% yield by using 3.0 equiv of prenylsilane at 90 ꢀC (entry 7), and
the decomposition of the product occurred at a higher temperature or
byusingalargeramountofthesilane. Fromtheseresults,Al-MCM-41-
5
t-Bu
1
a
TES¼triethylsilyl, TBDMS¼tert-butyldimethylsilyl, TBDPS¼tert-butyldiphenyl-
silyl.
b
c
catalyzed allylation with allylsilane was found to occur at
the silane like traditional Lewis acid-promoted reactions1 and the
steric hindrance of the -carbon had a large influence on the reaction.
g-carbon of
Isolated yield after column chromatography.
Al-MCM-41 (50 mg) was used.
g
entries 1 and 2). Although the reactivity of allyltert-butyldiphe-
nylsilane was relatively low, the reaction of 4-nitrobenzaldehyde
with allyltert-butyldiphenylsilane afforded the desired product in
The following experiment was carried out to examine whether
the reaction occurs on the surface of Al-MCM-41 or not. A sus-
pension of Al-MCM-41 (30 mg, Si/Al¼26, dried prior to use at
Table 9
Allylation of benzaldehyde with substituted allylsilanes catalyzed by Al-MCM-41
R1
Al-MCM-41
Me3SiO
Ph
R1
O
(Si/Al = 26)
R2
SiMe3
+
conditions
Ph
H
R2 R3
13
R3
1a
(1.0 mmol)
12
Entry
1
Silane (equiv)
Al-MCM-41 (mg)
30
Solvent (0.5 M)
CH2Cl2
Temp (ꢀC)
Time (h)
1
Product
Me3SiO
Ph
OSiMe3
Yielda(%)
89
SiMe3
30
30
E:Z = 1:3b
1.5
1.5
SiMe3
E:Z = 1:3b
2
3
30
30
CH2Cl2
1
N.R.
35
Ph
OSiMe3
SiMe3
Toluene
60
60
4.5
Ph
E:Z = 1:3b
1.5
1.5
dr = 1:1b
OSiMe3
SiMe3
E:Z = 1:3b
4
100
100
Toluene
Toluene
4.5
1
47
88
Ph
dr = 1:1b
OSiMe3
SiMe3
E:Z = 1:3b
5
6
60
Ph
dr = 1:1b
2.0
OSiMe3
SiMe3
SiMe3
100
100
Toluene
Toluene
60
90
4.5
3.5
13
58
Ph
2.0
3.0
OSiMe3
7
Ph
a
Isolated yield after column chromatography.
Determined by 1H NMR analysis.
b

2086
S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
120 ꢀC for 1 h under vacuum), benzaldehyde (1.0 mmol), and
allyltrimethylsilane (1.5 mmol) in dichloromethane (2.0 mL) was
stirred at 30 ꢀC. After 30 min, Al-MCM-41 was removed by filtra-
tion. The reaction was not completed at that time. The filtrate was
stirred at the same temperature and monitored by TLC analysis. The
TLC analysis showed that benzaldehyde remained and the product
did not increase after 24 h, whereas the reaction was completed in
1 h when the catalyst was not removed (Table 2, entry 7). This re-
sult indicates that the Al-MCM-41 catalyzes the reaction as a het-
erogeneous catalyst, and any homogeneous species, such as
a trimethylsilyl cation generated in situ or an active aluminum
species leached from the catalyst, are not the real catalyst of the
reaction. The recovery and reuse of the catalyst were also examined
in the reaction of 4-nitrobenzaldehyde with allyltrimethylsilane
(Table 10). The catalyst was recovered by filtration and washed with
dichloromethane. The recovered catalyst was then dried at 70 ꢀC
for 15 min, treated at 120 ꢀC for 1 h under vacuum, and used in
a next run. The catalyst could be reused three times without a sig-
nificant loss of catalytic activity.
compounds and acetals to afford the corresponding homoallyl
alcohol derivatives. The remarkable high catalytic activity of Al-
MCM-41 over amorphous silica/alumina and aluminum-free mes-
oporous silicate was observed in the reaction. Moreover, Al-MCM-
41 became the first catalyst that exhibits high acetal selectivity over
carbonyl compound among the catalyst that activates both acetals
and carbonyl compounds in Sakurai allylation. The reaction of al-
dehyde with substituted allylsilanes took place regioselectively at
the g-carbon of allylsilanes, and the steric hindrance of the g-car-
bon strongly affected the reactivity of allylsilanes. Furthermore, it
became apparent that the reactants were activated by catalytic
amount of active sites on the surface of Al-MCM-41, and the catalyst
was reusable without a significant loss of catalytic activity.
4. Experimental section
4.1. General
The structures of mesoporous materials were characterized by
using X-ray diffraction (XRD). XRD patterns were recorded on a Mac
Science M3X Model 1030 diffractometer equipped with a Cu Ka X-ray
Table 10
Reuse of Al-MCM-41a
source (40 kV, 20 mA). Nitrogen adsorptionedesorption measure-
ments were carried out at 77 K using a gas adsorption analyzer
(Belsorp 28SA, Bel Japan). The specific surface areas (SBET) were esti-
mated using the BrunauereEmmetteTeller (BET) method. The aver-
age pore-size of the mesoporous materials was obtained from
the adsorption branch of the isotherm using the Barrette
JoynereHalenda (BJH) method. The contents of Al in aluminosilicates
were measured by using inductively coupled plasma spectrometer
(ICP, ICP-8000E, Shimadzu). JRC-SAH-1 (Si/Al¼2, SBET: 528 m2/g) and
JRC-SAL-2 (Si/Al¼5, SBET: 617 m2/g) were obtained from Catalysis
Society of Japan as reference catalysts. All air-sensitive experiments
were carried out under an atmosphere of argon. IR spectra were
recorded on an HORIBA FT-730 spectrometer.1H and 13C NMR spectra
were recorded on JEOL JNM-EX270, JEOL JNM-AL400 or Brucker DRX-
300 spectrometer using CDCl3 as a solvent. Tetramethylsilane
(0.00 ppm) served as an internal standard in 1H NMR and CDCl3
Run
Al-MCM-41 (mg)
4-NO2C6H4CHO (mmol)
Yieldb(%)
1
2
3
4
60
53
38
25
2.0
1.8
1.3
0.8
92
94
94
93
a
In the presence of Al-MCM-41 (30 mg/mmol, Si/Al¼26), the reaction of 4-
nitrobenzaldehyde with 1.5 equiv of allyltrimethylsilane was carried out in
dichloromethane (0.5 M) at 30 ꢀC for 0.5 h.
b
Isolated yield after column chromatography.
Finally, the amount of active site on Al-MCM-41 was estimated by
the addition of triethylamine to a reaction mixture (Fig. 1). To an
activated Al-MCM-41 (30 mg, Si/Al¼23, dried prior to use at 120 ꢀC
for 1 h under vacuum), benzaldehyde (1.0 mmol) and triethylamine
(0.001e0.01 mmol) in dichloromethane (1.5 mL) was added at 30 ꢀC.
Allyltrimethylsilane (1.5 mmol) in dichloromethane (0.5 mL) was
then added to the stirred suspension and the mixture was stirred at
30 ꢀC for 1 h. As shown in Fig. 1, only 0.005 mmol of triethylamine
was enough to deactivate Al-MCM-41 completely. The result in-
dicates that Al-MCM-41 acts as a catalyst in the reaction and its
turnover number is 200. As for aluminum content of Al-MCM-41 (Si/
Al¼23), there are 0.021 mmol of aluminum atoms in 30 mg of the
catalyst. Therefore, the active site of Al-MCM-41 is about 25% of all
aluminum moieties. They probablyexistonthesurface ofmesopores.
(77.0 ppm) in 13C NMR. TLC analyses were done on silica-gel 60 F254
-
precoated aluminum backed sheets (E. Merck). Toyo filter paper No.1
was used for filtration. Wakogel C-200 and Silica-gel 60N (spherical,
neutral, 63e210 mm) were used for column chromatography. Diethyl
ether (Et2O) (dehydrated) and tetrahydrofuran (THF) (dehydrated,
stabilizer free), were purchased from Kanto Chemical Co., Inc. Other
solvents were purified and dried according to standard procedures.
All aldehydes, ketones, and allyltrimethylsilane were commercially
available. All acetals,23 allyltriethylsilane,17 allyltert-butyldimethylsi-
lane,18 allyltert-butyldiphenylsilane,19 methallyltrimethylsilane,20
crotyltrimethylsilane,21 and trimethylprenylsilane22 were synthe-
sized according to the literature procedure and fully characterized by
IR and 1H, 13C NMR spectroscopy.
100
50
4.2. Preparation of catalysts
4.2.1. Synthesis of Al-MCM-4111. To a stirred suspension of cetyl-
trimethylammonium bromide (CTMABr; 8.75 g, 24.0 mmol) in
water (350 mL) at 50 ꢀC, tetramethylammonium hydroxide
(TMAOH; 26.3 g, 72.0 mmol) in water (99 mL) and aluminum trii-
sopropoxide (Al(OiPr)3; 1.36 g, 6.67 mmol) were added. Tetraethyl
orthosilicate (TEOS; 41.7 g, 200 mmol) was then slowly added to
the suspension and stirred at 35 ꢀC for 4 h (input Si/Al atomic ratio
was 30). The mixture was heated at 100 ꢀC in an oven for 4 days
without stirring and then filtered off, washed with water, and dried
at 100 ꢀC to give 17.8 g of as-synthesized sample. This sample
(17.0 g) was heated to 130 ꢀC for 50 min, heated at 130 ꢀC for 5 h.
The temperature was raised to 550 ꢀC for 5 h and the sample was
calcined at that temperature for 10 h to afford Al-MCM-41 (10.2 g,
0
0.005
Et3N / mmol
0.01
Fig. 1. Poisoning effect of triethylamine on Al-MCM-41-catalyzed allylation of benz-
aldehyde with allyltrimethylsilane.
3. Conclusion
In conclusion, Al-MCM-41 was found to act as an effective het-
erogeneous catalyst for Sakurai allylation of both carbonyl

S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
2087
Si/Al¼26) as a white powder. The Si/Al atomic ratio was determined
to be 26 by ICP analysis. The specific surface area (SBET) and the
average pore diameter (BJH) of Al-MCM-41 were 1120 m2/g and
2.7 nm, respectively. Al-MCM-41 (Si/Al¼23, SBET: 1031 m2/g, BJH:
2.7 nm) was obtained in a next batch. There was no difference in
catalytic activity between Al-MCM-41 (Si/Al¼26) and Al-MCM-41
(Si/Al¼23).
column chromatography (hexane/ethyl acetate¼8:1) to give
1-phenylbut-3-en-1-ol26a as a colorless oil (0.133 g, 90%); IR (neat):
nmax 3369, 1641, 1494, 1454, 1049, 916, 758, 700 cmꢁ1 1H NMR
;
(270 MHz, CDCl3):
d (ppm) 7.24e7.37 (m, 5H), 5.74e5.89 (m, 1H),
5.12e5.21 (m, 2H), 4.71e4.77 (m, 1H), 2.43e2.58 (m, 2H), 2.05 (d,
J¼3.3 Hz, 1H); 13C NMR (67.8 MHz, CDCl3):
d (ppm) 143.7, 134.3,
128.1,127.2,125.6,117.9, 73.2, 43.6. All desilylated products exhibited
spectroscopic data consistent with the previously reported ones in
the literature.26
Al-MCM-41 (Si/Al¼34, SBET: 1101 m2/g, BJH: 2.7 nm) and Al-
MCM-41 (Si/Al¼48, SBET: 1135 m2/g, BJH: 2.7 nm) were synthesized
by changing the input Si/Al atomic ratio from 30 to 50 and 70,
respectively.
4.4. Typical experimental procedure for Al-MCM-41-catalyzed
allylation of acetals (Table 5, entry 1)
4.2.2. Synthesis of SiO2/Al2O3. Amorphous silica/alumina (SiO2/
Al2O3) was synthesized according to the same procedure as the one
used in the synthesis of Al-MCM-41 without the addition of the
surfactant, CTMABr. The Si/Al atomic ratio was determined to be 31
by ICP analysis. The specific surface area (SBET) was 385 m2/g.
Under an atmosphere of argon, to a mixture of benzaldehyde
dimethyl acetal (0.152 g, 1.0 mmol) and Al-MCM-41 (30 mg, Si/
Al¼48, dried prior to use at 120 ꢀC for 1 h under vacuum) in
dichloromethane (1.5 mL), allyltrimethylsilane (0.172 g, 1.5 mmol)
in dichloromethane (0.5 mL) was added through a syringe at 30 ꢀC.
The reaction mixture was stirred at 30 ꢀC for 45 min. The catalyst
was removed by filtration and washed with dichloromethane
(40 mL). After the filtrate was concentrated under reduced pres-
sure, almost pure homoallyl methyl ether was obtained. Further
purification by silica-gel column chromatography (hexane to hex-
ane/Et2O¼10:1) afforded 4-methoxy-4-phenylbut-1-ene27a as
a colorless oil (0.151 g, 93%); IR (neat): nmax 3028, 2980, 2936, 2821,
4.2.3. Synthesis of MCM-41. Aluminum-free MCM-41 was synthe-
sized according to the same procedure as the one used in the
synthesis of Al-MCM-41 without the addition of aluminum source,
Al(OiPr)3. The specific surface area (SBET) and the average pore di-
ameter (BJH) were 1080 m2/g and 2.6 nm, respectively.
4.2.4. Synthesis of SBA-1524. Triblock copolymer poly(ethylene
glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol)
(P123; 38.4 g, 6.62 mmol) was dissolved in a mixture of water
(1010 g) and concentrated hydrochloric acid (256 g) with stirring at
35 ꢀC. To the resulting solution, TEOS (81.9 g, 393 mmol) was added
and stirred at 35 ꢀC for 20 h. The mixture was then heated at 100 ꢀC
in an oven for 20 h without stirring. The mixture was filtered off,
washed with water and air-dried at room temperature to yield
23.2 g of as-synthesized sample. This sample was calcined at 550 ꢀC
for 10 h (heating rate¼1.4 K/min), resulting in a white powder. The
specific surface area (SBET) and the average pore diameter (BJH)
were 925 m2/g and 7.0 nm, respectively.
1641, 1454, 1357, 1100, 914, 701 cmꢁ1
(ppm) 7.26e7.35 (m, 5H), 5.69e5.85 (m, 1H), 5.00e5.09 (m, 2H),
4.17 (t, J¼5.9 Hz, 1H), 3.22 (s, 3H), 2.52e2.62 (m, 1H), 2.36e2.46 (m,
1H); 13C NMR (67.8 MHz, CDCl3):
(ppm) 141.4, 134.6, 128.1, 127.4,
;
1H NMR (270 MHz, CDCl3):
d
d
126.5, 116.7, 83.5, 56.4, 42.5. All allylated products are known
compounds and characterized by IR and 1H, 13C NMR
spectroscopy.3d,f,27
4.5. Synthesis of 1-phenylbut-3-en-1-ol (Scheme 2)
Under an atmosphere of argon, to a mixture of 2-phenyl-1,3-
dioxane (7) (0.164 g, 1.0 mmol) and Al-MCM-41 (30 mg, Si/Al¼48,
dried prior to use at 120 ꢀC for 1 h under vacuum) in dichloro-
methane (1.5 mL), allyltrimethylsilane (0.343 g, 3.0 mmol) in
dichloromethane (0.5 mL) was added through a syringe at 30 ꢀC.
The reaction mixture was stirred at 30 ꢀC for 2 h. The catalyst was
removed by filtration and washed with dichloromethane (40 mL).
After the filtrate was concentrated under reduced pressure, the
crude product 8 was dissolved in MeOH (3 mL), and 1 M aq HCl
(1 mL) was added. The reaction mixture was stirred at room tem-
perature for 30 min. Water and Et2O were added to the reaction
mixture and the organic layer was separated. The aqueous layer
was extracted with Et2O three times. The combined organic layer
was washed with water and brine, and dried over anhydrous
Na2SO4. After removal of the solvent under reduced pressure, the
crude alcohol was obtained and used in a next step without further
purification.
4.3. Typical experimental procedure for Al-MCM-41-catalyzed
allylation of carbonyl compounds (Table 2, entry 7)
Under an atmosphere of argon, to a mixture of benzaldehyde
(0.106 g, 1.0 mmol) and Al-MCM-41 (30 mg, Si/Al¼26, dried prior to
use at 120 ꢀC for 1 h under vacuum) in dichloromethane (1.5 mL),
allyltrimethylsilane (0.172 g, 1.5 mmol) in dichloromethane
(0.5 mL) was added through a syringe at 30 ꢀC. The reaction mix-
ture was stirred at 30 ꢀC for 1 h. The catalyst was removed by fil-
tration and washed with dichloromethane (40 mL). After the
filtrate was concentrated under reduced pressure, crude product
was purified by silica-gel column chromatography (hexane/
Et2O¼20:1) to afford 4-trimethylsiloxy-4-phenyl-1-butene25 as
a colorless oil (0.203 g, 92%); IR (neat): nmax 2957, 1641, 1493, 1454,
1252, 1089, 840 cmꢁ1
; d (ppm)
1H NMR (270 MHz, CDCl3):
ꢀ
7.20e7.35 (m, 5H), 5.69e5.85 (m, 1H), 4.99e5.07 (m, 2H), 4.66 (dd,
To a stirred suspension of crushed 4 A MS (0.90 g) and pyr-
J¼7.6, 5.3 Hz, 1H), 2.34e2.54 (m, 2H), 0.04 (s, 9H); 13C NMR
idinium dichromate (0.376 g, 1.0 mmol) in dichloromethane
(12 mL), the crude alcohol in dichloromethane (9.0 mL) was added.
The reaction mixture was stirred at room temperature for 14 h and
the resulting precipitates were removed by silica-gel column
chromatography (hexane/Et2O¼4:1). After removal of the solvent
under reduced pressure, the residue was dissolved in MeOH
(15 mL). To the solution, 10 M aq KOH (5 mL) was added. The re-
action mixture was stirred at room temperature for 14 h. Water and
Et2O were added to the reaction mixture and the organic layer was
separated. The aqueous layer was extracted with Et2O three times.
The combined organic layer was washed with water and brine, and
dried over anhydrous Na2SO4. After removal of the solvent under
reduced pressure, the crude product was purified by silica-gel
(67.8 MHz, CDCl3):
74.9, 45.1, 0.3.
d (ppm) 144.7, 135.2, 128.0, 126.9, 125.8, 116.7,
Desilylation was performed to characterize the products because
all desilylated products are known compounds. To a stirred solution
of 4-trimethylsiloxy-4-phenyl-1-butene (0.220 g, 1.0 mmol) in
MeOH (2 mL), 1 M aq HCl (2 mL) was added and the mixture was
stirred at room temperature for 10 min. After the reaction was
completed, ethyl acetate and water were added. The organic layer
was separated and the aqueous layer was extracted with ethyl ace-
tate threetimes. The combined organic layer was washed with brine,
and dried over anhydrous Na2SO4. After removal of the solvent
under reduced pressure, crude product was purified by silica-gel

2088
S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
4. (a) Sartori, G.; Ballini, R.; Bigi, F.; Bosica, G.; Maggi, R.; Righi, P. Chem. Rev. 2004,
104, 199e250; (b) Corma, A.; García, H. Chem. Rev. 2003, 103, 4307e4365; (c)
Okuhara, T. Chem. Rev. 2002, 102, 3641e3665.
column chromatography (hexane/Et2O¼4:1) to afford 1-phenylbut-
3-en-1-ol (9)26a as a colorless oil (0.126 g, 85%).
5. Kawai, M.; Onaka, M.; Izumi, Y. Chem. Lett. 1986, 381e384.
6. Kawabata, T.; Kato, M.; Mizugaki, T.; Ebitani, K.; Kaneda, K. Chem.dEur. J. 2005,
11, 288e297.
4.6. Typical experimental procedure for chemoselective
allylation (Table 7, entry 1)
7. Sasidharan, M.; Tatsumi, T. Chem. Lett. 2003, 32, 624e625.
8. (a) Kresge, C. T.; Lenowicz, M. E.; Roth, W. J.; Vartuli, J. C.; Beck, J. S. Nature 1992,
€
359, 710e712; (b) Hoffmann, F.; Cornelius, M.; Morell, J.; Froba, M. Angew.
Under an atmosphere of argon, to a mixture of benzaldehyde
(0.106 g, 1.0 mmol), benzaldehyde dimethyl acetal (0.152 g,
1.0 mmol), and Al-MCM-41 (30 mg, Si/Al¼48, dried prior to use at
120 ꢀC for 1 h under vacuum) in dichloromethane (1.5 mL), allyl-
trimethylsilane (0.126 g, 1.1 mmol) in dichloromethane (0.5 mL)
was added through a syringe at 30 ꢀC. The reaction mixture was
stirred at 30 ꢀC for 45 min. The catalyst was removed by filtration
and washed with dichloromethane (40 mL). After the filtrate was
concentrated under reduced pressure, nitromethane (61.0 mg,
1.0 mmol) in CDCl3 was added to the crude product as an internal
standard. 1H NMR analysis of the crude product showed 92% yield
of 4-methoxy-4-phenylbut-1-ene, and 4-trimethylsiloxy-4-phenyl-
1-butene was not detected.
Chem., Int. Ed. 2006, 45, 3216e3251; (c) Xiao, F.-S. Top. Catal. 2005, 35, 9e24; (d)
Ziolek, M. Catal. Today 2004, 90, 145e150; (e) Wight, A. P.; Davis, M. E. Chem.
Rev. 2002, 102, 3589e3614; (f) Corma, A. Top. Catal. 1997, 4, 249e260.
9. (a) Ratnamala, A.; Subrahmanyam, M.; Kumari, V. D. Appl. Catal., A 2004, 264,
219e224; (b) Shanmugapriya, K.; Palanichamy, M.; Murugesan, V. Catal. Com-
mun. 2006, 7, 47e51; (c) Ratnamala, A.; Lalitha, K.; Reddy, J. K.; Kumari, V. D.;
Subrahmanyam, M. J. Mol. Catal. A: Chem. 2008, 279, 112e118; (d) Katada, N.;
Fujinaga, H.; Nakamura, Y.; Okumura, K.; Nishigaki, K.; Niwa, M. Catal. Lett.
2002, 80, 47e51; (e) Ajaikumar, S.; Pandurangan, A. J. Mol. Catal. A: Chem. 2007,
266, 1e10; (f) Iwanami, K.; Choi, J.-C.; Lu, B.; Sakakura, T.; Yasuda, H. Chem.
Commun. 2008, 1002e1004; (g) Iwanami, K.; Seo, H.; Choi, J.-C.; Sakakura, T.;
Yasuda, H. Tetrahedron 2010, 66, 1898e1901; (h) Murata, H.; Ishitani, H.;
Iwamoto, M. Tetrahedron Lett. 2008, 49, 4788e4791; (i) Ito, S.; Yamaguchi, H.;
Kubota, Y.; Asami, M. Chem. Lett. 2009, 38, 700e701.
10. (a) Ito, S.; Yamaguchi, H.; Kubota, Y.; Asami, M. Tetrahedron Lett. 2009, 50,
2967e2969; (b) Ito, S.; Hayashi, A.; Komai, H.; Kubota, Y.; Asami, M. Tetrahedron
Lett. 2010, 51, 4243e4245.
11. Chen, C.-Y.; Li, H.-X.; Davis, M. E. Microporous Mater. 1993, 2, 17e26.
12. Silyl enol ethers were formed from enols of the aliphatic aldehydes with al-
lyltrimethylsilane, which is known to act as a silylating reagent of hydroxy
groups in the presence of acid catalysts. (a) Morita, T.; Okamoto, Y.; Sakurai, H.
Synthesis 1981, 745e746; (b) Onaka, M.; Hosokawa, Y.; Higuchi, K.; Izumi, Y.
Tetrahedron Lett. 1993, 34, 1171e1172.
13. Recently, an allylation of acetals by allylsilanes using silicaealumina was re-
ported. It required higher reaction temperature and longer reaction time than
Al-MCM-41 catalyzed reaction Motokura, K.; Yoneda, H.; Miyaji, A.; Baba, T.
Green Chem. 2010, 12, 1373e1375.
14. (a) Hosokawa, T.; Shinohara, T.; Ooka, Y.; Murahashi, S.-I. Chem. Lett. 1989,
2001e2004; (b) Chen, S.-H.; Sun, X.; Boyer, R.; Paschal, J.; Zeckner, D.; Current,
W.; Zweifel, M.; Rodriguez, M. Bioorg. Med. Chem. Lett. 2000, 10, 2107e2110.
15. Ooi, T.; Tayama, E.; Takahashi, M.; Maruoka, K. Tetrahedron Lett. 1997, 38,
7403e7406.
4.7. Reuse of Al-MCM-41 (Table 10)
The reaction of 4-nitrobenzaldehyde (0.302 mg, 2.0 mmol) with
allyltrimethylsilane (0.343 mg, 3.0 mmol) was carried out in the
presence of Al-MCM-41 (60 mg, Si/Al¼26) according to the typical
experimental procedure for carbonyl compounds. After the re-
action, the recovered catalyst was dried at 70 ꢀC for 15 min. The
catalyst (53 mg) was then dried at 120 ꢀC for 1 h under vacuum and
used in a second run.
Acknowledgements
16. Li, W.-D. Z.; Zhang, X.-X. Org. Lett. 2002, 4, 3485e3488.
17. Lewis, L. N. J. Am. Chem. Soc. 1990, 112, 5998e6004.
Y.K. thanks New Energy and Industrial Technology Development
Organization (NEDO) for financial support.
18. (a) Murakami, K.; Yorimitsu, H.; Oshima, K. J. Org. Chem. 2009, 74, 1415e1417;
(b) Morita, T.; Okamoto, Y.; Sakurai, H. Tetrahedron Lett. 1980, 21, 835e838.
19. Imazeki, S.; Sugawara, H.; Sano, A.; Akiyama, T. Bull. Chem. Soc. Jpn. 2008, 81,
623e629.
20. Li, L.-H.; Wang, D.; Chan, T. H. Tetrahedron Lett. 1991, 32, 2879e2882.
21. (a) Hosomi, A.; Iguchi, H.; Sakurai, H. Chem. Lett. 1982, 223e226; (b) Hosomi, A.;
Shirahata, A.; Sakurai, H. Chem. Lett. 1978, 901e904.
Supplementary data
Characterization data (IR and 1H, 13C NMR spectra) of synthe-
sized compounds are available. Supplementary data associated
with this article can be found, in the online version, at doi:10.1016/
j.tet.2011.01.055. These data include MOL files and InChIKeys of the
most important compounds described in this article.
22. Lipshutz, B. H.; Hackmann, C. J. Org. Chem. 1994, 59, 7437e7444.
23. (a) Ladepeche, A.; Tam, E.; Ancel, J.-E.; Ghosez, L. Synthesis 2004, 1375e1380;
(b) Miura, K.; Izumi, H.; Kinoshita, H.; Ichikawa, J.; Hosomi, A. Chem. Lett. 2009,
38, 1204e1205; (c) Wiles, C.; Watts, P.; Haswell, S. J. Tetrahedron 2005, 61,
5209e5217; (d) Fukuzumi, T.; Bode, J. W. J. Am. Chem. Soc. 2009, 131,
ꢂ
ꢃ
3864e3865; (e) Myles, L.; Gore, R.; Spulak, M.; Gathergood, N.; Connon, S. J.
Green Chem. 2010, 12, 1157e1162; (f) Tateiwa, J.; Horiuchi, H.; Uemura, S. J. Org.
Chem. 1995, 60, 4039e4043; (g) Sakai, N.; Moritaka, K.; Konakahara, T. Eur. J.
Org. Chem. 2009, 4123e4127; (h) Das, P.; McNulty, J. Eur. J. Org. Chem. 2010,
3587e3591; (i) Gregg, B. T.; Golden, K. C.; Quinn, J. F. Tetrahedron 2008, 64,
3287e3295; (j) Kropp, P. J.; McNeely, S. A.; Davis, R. D. J. Am. Chem. Soc. 1983,
105, 6907e6915; (k) Baghdasarian, G.; Woerpel, K. A. J. Org. Chem. 2006, 71,
6851e6858; (l) Gasparrini, F.; Giovannoli, M.; Misiti, D.; Palmieri, G. Tetrahe-
dron 1984, 40, 1491e1500; (m) Bassetti, M.; Floris, B. J. Chem. Soc., Perkin Trans. 2
1988, 227e233.
References and notes
1. (a) Hosomi, A.; Sakurai, H. Tetrahedron Lett. 1976, 1295e1298; (b) Hosomi, A.;
ꢁ
Endo, M.; Sakurai, H. Chem. Lett. 1976, 941e942; (c) Fleming, I.; Dunogues, J.;
ꢁ
Smithers, R. Org. React. 1989, 37, 57e575; (d) Deleris, G.; Dunogues, J.; Calas, R.
Tetrahedron Lett. 1976, 2449e2450.
2. For catalytic allylation of carbonyl compounds, see (a) Aggarwal, V. K.; Vennall,
G. P. Tetrahedron Lett. 1996, 37, 3745e3746; (b) Aggarwal, V. K.; Vennall, G. P.
Synthesis 1998, 1822e1826; (c) Yang, Y.; Wang, M.; Wang, D. Chem. Commun.
1997, 1651e1652; (d) Yadav, J. S.; Chand, P. K.; Anjaneyulu, S. Tetrahedron Lett.
2002, 43, 3783e3784; (e) Watahiki, T.; Oriyama, T. Tetrahedron Lett. 2002, 43,
8959e8962; (f) Davis, A. P.; Jaspars, M. Ang. Chem., Int. Ed. 1992, 31, 470e471;
(g) Davis, A. P.; Jaspars, M. J. Chem. Soc., Perkin Trans. 1 1992, 2111e2118; (h)
Komatsu, N.; Uda, M.; Suzuki, H.; Takahashi, T.; Domae, T.; Wada, M. Tetrahe-
dron Lett. 1997, 38, 7215e7218; (i) Marx, A.; Yamamoto, H. Angew. Chem., Int. Ed.
2000, 39, 178e181; (j) Onishi, Y.; Ito, T.; Yasuda, M.; Baba, A. Eur. J. Org. Chem.
2002, 1578e1581; (k) Fang, X.; Watkin, J. G.; Warner, B. P. Tetrahedron Lett.
2000, 41, 447e449.
3. For catalytic allylation of acetals, see (a) Spafford, M. J.; Anderson, E. D.; Lacey, J.
R.; Palma, A. C.; Mohan, R. S. Tetrahedron Lett. 2007, 48, 8665e8667; (b) Arai, S.;
Sudo, Y.; Nishida, A. Tetrahedron 2005, 61, 4639e4642; (c) Jung, M. E.; Maderna,
A. Tetrahedron Lett. 2004, 45, 5301e5304; (d) Watahiki, T.; Akabane, Y.; Mori, S.;
Oriyama, T. Org. Lett. 2003, 5, 3045e3048; (e) Wieland, L. C.; Zerth, H. M.; Mohan,
R. S. Tetrahedron Lett. 2002, 43, 4597e4600; (f) Yadav, J. S.; Subba Reddy, B. V.;
Srihari, P. Synlett 2001, 673e675; (g) Kamata, M.; Yokoyama, Y.; Karasawa, N.;
Kato, M.; Hasegawa, E. Tetrahedron Lett. 1996, 37, 3483e3486; (h) Trehan, A.; Vij,
A.; Walia, M.; Kaur, G.; Verma, R. D.; Trehan, S. Tetrahedron Lett. 1993, 34,
7335e7338; (i) Sakurai, H.; Sasaki, K.; Hosomi, A. Tetrahedron Lett. 1981, 22,
745e748; (j) Tsunoda, T.; Suzuki, M.; Noyori, R. Tetrahedron Lett. 1980, 21, 71e74.
24. (a) Zhao, D.; Huo, Q.; Feng, J.; Chmelka, B. F.; Stucky, G. D. J. Am. Chem. Soc. 1998,
120, 6024e6036; (b) Zhao, D.; Feng, J.; Huo, Q.; Melosh, N.; Fredrickson, G. H.;
Chmelka, B. F.; Stucky, G. D. Science 1998, 279, 548e552.
25. Comins, D. L.; Dinsmore, J. M.; Marks, L. R. Chem. Commun. 2007, 4170e4171.
26. (a) Denmark, S. E.; Nguyen, S. T. Org. Lett. 2009, 11, 781e784; (b) Nowrouzi, F.;
Thadani, A. N.; Batey, R. A. Org. Lett. 2009, 11, 2631e2634; (c) Kim, I. S.; Ngai,
M.-Y.; Krische, M. J. J. Am. Chem. Soc. 2008, 130, 6340e6341; (d) Bower, J. F.;
Skucas, E.; Patman, R. L.; Krische, M. J. J. Am. Chem. Soc. 2007, 129, 15134e15135;
(e) Shen, K.-H.; Yao, C.-F. J. Org. Chem. 2006, 71, 3980e3983; (f) Li, G.-l.; Zhao, G.
Org. Lett. 2006, 8, 633e636; (g) Traverse, J. F.; Zhao, Y.; Hoveyda, A. H.; Snapper,
M. L. Org. Lett. 2005, 7, 3151e3154; (h) Canales, E.; Prasad, K. G.; Soderquist, J. A.
J. Am. Chem. Soc. 2005, 127, 11572e11573; (i) Hirayama, L. C.; Gamsey, S.;
Knueppel, D.; Steiner, D.; DeLaTorre, K.; Singaram, B. Tetrahedron Lett. 2005, 46,
ꢃ
2315e2318; (j) Goujon, J.-Y.; Zammattio, F.; Chretien, J.-M.; Beaudet, I. Tetra-
hedron 2004, 60, 4037e4049; (k) Buchmann, B.; Marschall-Weyerstahl, H.;
Weyerstahl, P. Tetrahedron 1984, 40, 3393e3398; (l) Boldrini, G. P.; Savoia, D.;
Tagliavini, E.; Trombini, C.; Umani-Ronchi, A. J. Org. Chem. 1983, 48, 4108e4111;
(m) Mani, N. S.; Mapes, C. M.; Wu, J.; Deng, X.; Jones, T. K. J. Org. Chem. 2006, 71,
5039e5042.
27. (a) Jung, M. E.; Maderna, A. J. Org. Chem. 2004, 69, 7755e7757; (b) Barbero, M.;
Bazzi, S.; Cadamuro, S.; Dughera, S.; Piccinini, C. Synthesis 2010, 315e319; (c)

S. Ito et al. / Tetrahedron 67 (2011) 2081e2089
2089
Olivero, S.; Perriot, R.; Dunach, E.; Baru, A. R.; Bell, E. D.; Mohan, R. S. Synlett
2006, 2021e2026; (d) Cui, Y.-M.; Huang, Q.-Q.; Xu, J.; Chen, L.-L.; Li, J.-Y.; Ye,
Q.-Z.; Li, J.; Nan, F.-J. Bioorg. Med. Chem. Lett. 2005, 15, 4130e4135; (e) Anzalone,
P. W.; Baru, A. R.; Danielson, E. M.; Hayes, P. D.; Nguyen, M. P.; Panico, A. F.;
Smith, R. C.; Mohan, R. S. J. Org. Chem. 2005, 70, 2091e2096; (f) Suga, S.; Suzuki,
S.; Yamamoto, A.; Yoshida, J. J. Am. Chem. Soc. 2000, 122, 10244e10245; (g) Torii,
S.; Inokuchi, T.; Takagishi, S.; Horike, H.; Kuroda, H.; Uneyama, K. Bull. Chem.
Soc. Jpn. 1987, 60, 2173e2188; (h) Kamata, M.; Nagai, S.; Kato, M.; Hasegawa, E.
Tetrahedron Lett. 1996, 37, 7779e7782; (i) Hermans, B.; Hevesi, L. J. Org. Chem.
1995, 60, 6141e6147.