Palladium-catalyzed 1-methylene-2-propenylation reactions of aryl bromides with 3,4-alkadien-1-ols via carbon-carbon bond cleavage for the synthesis of 2-aryl-1,3-butadiene derivatives

Article abstract of DOI:10.1246/bcsj.82.393

A method for the synthesis of 2-aryl-1,3-alkadienes has been developed. Treatment of aryl bromides with 3,4-alkadien-1-ols in the presence of a palladium catalyst results in 1-methylene-2-propenyl group transfer to aryl bromides. Taking advantage of palla

Full text of DOI:10.1246/bcsj.82.393

© 2009 The Chemical Society of Japan
Bull. Chem. Soc. Jpn. Vol. 82, No. 3, 393–400 (2009)
393
Palladium-Catalyzed 1-Methylene-2-propenylation Reactions of
Aryl Bromides with 3,4-Alkadien-1-ols via Carbon-Carbon Bond
Cleavage for the Synthesis of 2-Aryl-1,3-butadiene Derivatives
Junichi Imoto, Sayuri Hayashi, Koji Hirano, Hideki Yorimitsu,* and Koichiro Oshima*
Department of Material Chemistry, Graduate School of Engineering, Kyoto University,
Kyoto-daigaku Katsura, Nishikyo-ku, Kyoto 615-8510
Received September 19, 2008; E-mail: yori@orgrxn.mbox.media.kyoto-u.ac.jp, oshima@orgrxn.mbox.media.kyoto-u.
ac.jp
A method for the synthesis of 2-aryl-1,3-alkadienes has been developed. Treatment of aryl bromides with 3,4-
alkadien-1-ols in the presence of a palladium catalyst results in 1-methylene-2-propenyl group transfer to aryl bromides.
Taking advantage of palladium-mediated retro-allylation as an sp3C-sp3C bond cleavage reaction, one can regard 3,4-
alkadien-1-ols as 1-methylene-2-propenyl metal equivalents that are easy to prepare and are not sensitive to air and
moisture. In the event that the Diels-Alder dimerization of the product during the 1-methylene-2-propenylation reaction is
problematic, addition of N-methylpyrrole to the reaction mixture can efficiently suppress the dimerization. The reactions
of aryl bromides with 2-substituted 3,4-alkadien-1-ols yield the corresponding (E)-2-aryl-1,3-alkadienes stereoselectively.
Conjugated dienes are an important class of compounds that
can undergo numerous organic transformations. Among them,
2-aryl-1,3-alkadienes are useful precursors in organic syn-
thesis1 as well as in polymer chemistry.2 Development of new
and convenient methods for the preparation of 2-aryl-1,3-
alkadienes is thus important. Cross-coupling reactions of
aryl halides with 1-methylene-2-propenylmetal reagents may
provide an easy access to 2-aryl-1,3-alkadienes (eq 1).3
However, the reactions often result in moderate yields because
the products are prone to undergo polymerization or Diels-
Alder dimerization during the synthesis. Moreover, the prep-
arations of 1-methylene-2-propenylmetal reagents are not
always facile and functional group compatibility is far from
satisfactory.
Similar palladium-catalyzed reactions of aryl halides with
3,4-alkadien-1-ols were reported to afford 2-aryl-1,3-alka-
dienes.8 However, the scope of the reaction was narrow and
particularly, the synthesis of 2-aryl-1,3-butadienes resulted in
moderate yields. It was proposed that the reaction would begin
with carbopalladation followed by ¢-carbon elimination, which
is different from our working hypothesis.
Results and Discussion
Optimization. The reaction of 1-bromonaphthalene (2a,
Np = 1-naphthyl) with allenyl alcohol 1a was examined as a
model reaction. As the initial trial, treatment of 2a with 1a in
the presence of cesium carbonate (obtained from Wako Pure
R7
M
Ar
transition metal catalyst
M = Mg, Zn, Zr, B, Si
Ar
Ar–X
substrate
R6
+
ð1Þ
Ar
X
R3
R5
Pd
We have reported palladium-catalyzed regiospecific and
stereoselective allylations of aryl halides with homoallyl
alcohols via retro-allylation.4-6 We envisioned that the allyl-
transfer reaction via retro-allylation would be extended to the
synthesis of 2-aryl-1,3-alkadienes as outlined in Scheme 1.
After oxidative addition (Step 1), ligand exchange (Step 2)
would occur to afford palladium alkoxide B. Carbon-carbon
bond cleavage would then proceed via a six-membered
cyclic transition state, providing aryl(1-methylene-2-propenyl)-
palladium C selectively (Step 3). The subsequent reductive
elimination (Step 4) would furnish 2-aryl-1,3-alkadienes. No-
tably, any type of allenyl alcohol is readily available in two
steps from homoallyl alcohols via the corresponding dibromo-
cyclopropyl alcohols,7 which would allow us to prepare a wider
variety of 2-aryl-1,3-alkadienes.
R4
product
4)
1)
Ar R7
Ar
A
Pd
Pd
R6
X
R3
R5
C
R7 R6
R4
2)
R7
Ar R6
·
OH
3)
Pd
R1
·
O
R5
R2
O
R1
R3 R4
allenyl alcohol
R5
R2
R1 R2
R3 R4
B
Scheme 1. Working hypothesis.
Published on the web March 12, 2009; doi:10.1246/bcsj.82.393

394
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
Pd-Catalyzed 1-Methylene-2-propenylation
Table 3. Solvent Effect
Table 1. Effect of Base and Palladium Precursora)
5 mol% Pd salt
20 mol% PPh3
5 mol% Pd(OAc)2, 10 mol% DPPM
·
OH
Np
1.4 equiv K2CO3, Np–Br (2a)
1.4 equiv base
·
OH
OH
i
Np
Pr
Np–Br (2a)
i
Pr
(1.2 equiv)
solvent, temp, 6 h
1a
+
iPr
iPr
3a
iPr
iPr
toluene
reflux, 6 h
1a
Np
4
3a
(1.2 equiv)
Entry Solvent
Temp/°C
3a/%a)
2a/%a)
Entry Pd salt
Base
3a/%a) 4/%a) 2a/%a)
1
2
3
4
5
Toluene
1,4-Dioxane
Benzene
DMF
111 (reflux)
101 (reflux)
80 (reflux)
110
76
12
0
100
0
88 (79b))
b)
1
2
3
4
5
6
7
8
Pd(OAc)2
Cs2CO3
Cs2CO3
K2CO3
Na2CO3
K3PO4
K2CO3
K2CO3
K2CO3
54
75
75
8
50
46
11
15
15
3
9
15
14
16
23
22
8
0
9
65
0
33
36
48
c)
0
67
38
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
Pd(OAc)2
PdCl2
DMSO
110
0
a) Determined by 1H NMR analysis of crude products.
b) Isolated yield.
d)
[(³-allyl)PdCl]2
d)
Pd2(dba)3
Table 4. Effect of Leaving Group X and Substituent R
1
a) Determined by H NMR analysis of crude products. b) From
Wako Pure Chemical Co. (mean particle diameter: ca. 60 µm).
c) From Chemetall (mean particle diameter: ca. 20 µm).
d) 2.5 mol % of the palladium precursor was used.
5 mol% Pd(OAc)2
10 mol% DPPM
1.4 equiv K2CO3
Np
·
OH
+
Np–X
R1
R2
dioxane, reflux, 6 h
3a
1 (1.2 equiv)
R1
R2
3a/%a)
Table 2. Ligand Effect
Entry
X
1
iPr
iPr
iPr
iPr
Me
Ph
Ph
iPr
iPr
iPr
iPr
Me
Ph
H
88
76
8b)
20c)
49d)
62
5 mol% Pd(OAc)2
x mol% ligand
1.4 equiv K2CO3
Np–Br (2a)
1
2
3
4
5
6
7
Br
OTf
Cl
I
Br
Br
Br
1a
1a
1a
1a
1b
1c
1d
·
OH
OH
Np
+
iPr
iPr
iPr
iPr
toluene
reflux, 6 h
1a
Np
4
3a
(1.2 equiv)
34
Entry Ligand
x/mol % 3a/%a) 4/%a) 2a/%a)
a) Determined by 1H NMR analysis of crude products. b) 71%
of 1-chloronaphthalene was recovered. c) 60% of 1-iodonaph-
thalene was recovered. d) 35% of 1-bromonaphthalene was
recovered.
1
2
3
4
5
6
7
8
9
PPh3
20
20
20
20
20
20
10
20
20
10
5
75
56
65
75
32
26
54
56
18
76
54
53
64
9
10
8
11
10
7
12
0
0
9
0
0
0
0
46
0
9
66
12
0
28
0
P(2-MeC6H4)3
P(4-FC6H4)3
P(2-furyl)3
P(OPh)3
P(cC6H11)3
P(cC6H11)3
PMe3
Monodentate triarylphosphine ligands, triphenyl phosphite, and
tricyclohexylphosphine gave mixtures of 3a and 4 (Entries
1-7). Although trimethylphosphine and tributylphosphine sup-
pressed the formation of 4, the yields of 3a were moderate
(Entries 8 and 9). Interestingly, the use of 10 mol % of
bis(diphenylphosphino)methane (DPPM) proved to furnish 3a
selectively in high yield without affording 4 (Entry 10).
Decreasing the amount of DPPM to 5 mol % resulted in
contamination with 4 (Entry 11). The catalytic activity was
diminished when 1,2-bis(diphenylphosphino)ethane (DPPE)
was used (Entry 12). The use of bidentate 1,3-bis(diphenyl-
phosphino)propane (DPPP) provided a mixture of 3a and 4
(Entry 13). Overall, there are no clear correlations between the
characters of phosphine ligands and yields and selectivities.
Among the solvents tested, 1,4-dioxane was the best
(Table 3, Entry 2). Temperatures higher than 100 °C were
essential for the reaction: the reaction in boiling benzene
resulted in recovery of the starting materials (Entry 3). The
reactions in polar solvents such as DMF and DMSO provided
3a with unidentified by-products (Entries 4 and 5).
PBu3
10 DPPM
11 DPPM
12 DPPE
13 DPPP
0
14
1
10
10
11
1
a) Determined by H NMR analysis of crude products.
Chemical Co.) in refluxing toluene for 6 h afforded 2-(1-
naphthyl)-1,3-butadiene (3a) in 54% yield along with remain-
ing 2a (Table 1, Entry 1). The only detectable by-product was
alcohol 4, which carbopalladation of 2a followed by ¢-hydride
elimination would yield.9 The use of finely milled cesium
carbonate, which is available from Chemetall, increased the
yield of 3a to 75% (Entry 2). Potassium carbonate was as
effective as the milled cesium carbonate (Entry 3). Sodium
carbonate and potassium phosphate were less efficient
(Entries 4 and 5). Cost-efficient potassium carbonate was
chosen as the best base. Palladium acetate was far superior to
other palladium salts such as palladium chloride (Entries 6-8).
The results of ligand screening are summarized in Table 2.
Not only 1-bromonaphthalene but also 1-naphthyl trifluoro-
methanesulfonate underwent the reaction as well (Table 4,
Entry 2). 1-Chloronaphthalene resisted the reaction (Entry 3).

J. Imoto et al.
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
395
5 mol% Pd(OAc)2
10 mol% DPPM
1.4 equiv K2CO3
Ar–Br (2a–2c)
Table 5. Effect of Additive in the Reaction of 2d with 1a
Ar
5 mol% Pd(OAc)2
·
OH
Ar
10 mol% DPPM
1.2 equiv K2CO3
1.2 equiv additive
Ar
(2d)
Ar Br
+
iPr
iPr
Ar
5a
dioxane, reflux, 6 h
1a
·
OH
3a–3c
(1.2 equiv)
+
Ar
3d
dioxane, reflux
Ar = C6H4-4-CO2Et
iPr
iPr
1a
MeO
5b
Ph
(1.2 equiv)
Ar
Entry
1
Additive
Time/h
3d/%a) 5a + 5b/%a)
3a: 79% from 2a
3b: 71% from 2b
3c: 64% from 2c
3
45
17
Scheme 2. Reactions of sterically demanding or electron-
rich aryl bromides with 1a.
Ph
2
4.5
45
27
Ph
The reaction of 1-iodonaphthalene suffered from low con-
version (Entry 4). The efficiency of the reaction with 1b was
unsatisfactory (Entry 5). The smaller methyl groups would
retard the carbon-carbon bond cleavage process that utilizes the
release of the steric congestion around the hydroxy group.
Diphenyl-substituted alcohol 1c was the less efficient 1-
methylene-2-propenyl donor than 1a (Entry 6). The reaction
of secondary alcohol 1d8 proceeded with low efficiency under
the present reaction conditions (Entry 7). The triethylsilyl ether
of 1a failed to react under the reaction conditions.
Reactions of Aryl Bromides with 1a. With the optimized
conditions in hand, several aryl bromides were subjected to the
reactions (Scheme 2). The reactions of 2a, 2-bromobiphenyl
(2b), and 4-bromoanisole (2c) with 1a provided the corre-
sponding arylated 1,3-butadienes (3a-3c) in good isolated
yields. However, the reaction of ethyl 4-bromobenzoate (2d)
provided 3d in only 12% yield, albeit with full conversion
(eq 2). In the crude reaction mixture, we detected significant
amounts of 5a and 5b (5a/5b or 5b/5a = 57:43), which
resulted from the Diels-Alder dimerization of the initial
product 3d. Sterically demanding aryl group or electron-rich
aryl group of 3a-3c could fortunately prevent the dimerization.
This transformation thus proved to lack generality.
3
4
6
17
44
66
50
6.5
O
S
5
6
6
55
39
14
0
6b)
Me
N
7
9.5
6
71
58
18
12
H
N
8c)
t
CO2 Bu
N
9
6
59
29
a) Determined by 1H NMR analysis of crude products. b) 50%
of 2d was recovered. c) 25% of 2d was recovered.
inhibited the side reaction (Entries 5-9). Among them, N-
methylpyrrole suppressed the formation of 5 most efficiently
without diminishing the conversion of 2d (Entry 7).
Without suffering from the dimerization reaction, not only
ethyl 4-bromobenzoate (2d) but also other aryl bromides 2e-2h
of some generality were converted to the corresponding
arylated butadienes in good yield (Scheme 3). Although the
reaction of 4-bromobenzaldehyde (2g) was unsatisfactory, the
corresponding acetal 2h was converted more efficiently.
We have no exact ideas how the additives could suppress the
Diels-Alder reaction. Probably, these additives would coor-
dinate to palladium, deactivating the catalytic performance of
palladium for the Diels-Alder reaction.10
Ar
5 mol% Pd(OAc)2
Ar
10 mol% DPPM
1.4 equiv K2CO3
Ar–Br (2d)
·
OH
Ar
5a
iPr
+
Ar
iPr
(1.2 equiv)
dioxane, reflux, 8 h
Ar = C6H4-4-CO2Et
1a
3d 12%
5b
Ar
72%
(combined,
57:43)
Unfortunately, no reactions took place when heteroaromatic
halides were used as substrates. The reaction of 2- or 3-
bromopyridine or 2-bromothiophene with 1a resulted in
recovery of the starting materials.
ð2Þ
Development of Alternate Conditions to Suppress Diels-
Alder Dimerization. After struggling to minimize the
undesired dimerization reaction, we finally found that addition
of another conjugated diene could inhibit the Diels-Alder
reaction (Table 5, Entries 1 and 2). An unconjugated diene,
1,5-cyclooctadiene, was ineffective (Entry 3). Configuration-
ally regulated 1,2,3,4-tetramethylcyclopentadiene was a potent
inhibitor of the Diels-Alder reaction (Entry 4). Intriguingly,
additions of 5-membered heteroaromatic compounds efficiently
Scope of Allenyl Alcohols. Allenyl alcohol 1e was readily
prepared in two steps from 2-methyl-3-butyn-2-ol via Johnson-
Claisen rearrangement.11,12 Alcohol 1e reacted with aryl
bromides without suffering from the Diels-Alder dimerization
(Scheme 4). In reactions with 1e, tri(4-fluorophenyl)phosphine
was more effective than DPPM. The more basic cesium
carbonate (Wako) was used instead of potassium carbonate

396
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
Pd-Catalyzed 1-Methylene-2-propenylation
5 mol% Pd(OAc)2
10 mol% DPPM
1.2 equiv K2CO3
Table 6. Reactions with 1i for Stereoselective Synthesis of
(E)-2-Aryl-1,3-pentadienes 8
·
OH
Ar
1.2 equiv N-methylpyrrole
5 mol% Pd(OAc)2
+
Ar Br
10 mol% DPPM
K2CO3, (N-methylpyrrole)
iPr
Ar
iPr
·
dioxane, reflux, time
OH
1a
+
Ar Br
3e–3h
(1.2 equiv)
nPr
dioxane, reflux, time
nPr
(1.2 equiv)
8
1i
H
O
O
Ph
O
O
Time
/h
Yield
/%
Entry Ar-Br 2
Conditionsa)
8
3e: 75% from 2e
(4% without
N-methylpyrrole)
9 h
3f: 66% from 2f 3g: 44% from 2g 3h: 66% from 2h
7.5 h 6 h
1
2
3
4
5
6
7
8
Np-Br (2a)
2-PhC6H4Br (2b)
4-MeOC6H4Br (2c)
4-EtOC(=O)C6H4Br (2d)
4-PhC6H4Br (2e)
A
A
A
B
B
B
B
B
10
11
6
8a 94
8b 91
8c 57
6 h
8.5 8d 68
8e 72
7.5 8f 50
8g 41
10.5 8h 67
Scheme 3. Reactions of aryl bromides with 1a in the
presence of N-methylpyrrole.
9
4-AcC6H4Br (2f)
4-HC(=O)C6H4Br (2g)
4-[CH(OCH2CH2O)]-
C6H4Br (2h)
9
5 mol% Pd(OAc)2
20 mol% (4-FC6H4)3P
1.4 equiv Cs2CO3
·
OH
Ar
+
Ar Br
nPr
a) Conditions A: 0.17 M 2, 1.4 equiv K2CO3, without N-
methylpyrrole; Conditions B: 0.067 M 2, 1.2 equiv K2CO3, 1.2
equiv N-methylpyrrole.
dioxane, reflux, time
nPr
6
1e
(1.2 equiv)
OEt
MeO
Ph
O
Ar
Ar
nPr
Pd
Pd
·
(E)-8
(Z)-8
6a: 71% (58%) 6b: 58% (51%) 6c: 93% (40%) 6d: 56% (48%)
9 h 7 h 11h 8.5 h
O
Ar–Br
+
nPr
(E)-11
a Yields obtained by using 10 mol% DPPM are in parentheses.
10a favored
1i
+
Pd
Scheme 4. Reactions with allenyl alcohol 1ea.
·
nPr
O
Pd
Ar
Pd
nPr
(Z)-11
Ar
10b disfavored
·
·
OH
OH
Scheme 5. Explanation of the stereoselectivity.
nBu
nBu
nC6H13
nC6H13
nBu
nBu
1g
1h
pyrrole should be added to avoid the side reaction (Entries
4-8). The reactions of allenyl alcohols 1j and 1k also yielded
the corresponding (E)-dienes exclusively (eq 4).12
Figure 1. Allenyl alcohols that failed to yield conjugated
dienes.
5 mol% Pd(OAc)2
(Scheme 1, Step 2). Alcohol 1f12 having a 1,3-disubstituted
allene moiety was transformed into the corresponding diene
7 with slight E stereoselectivity (eq 3). The low stereo-
selectivity stemmed from facile isomerization of the initially
formed E isomer into the Z isomer. Because of steric
reasons, no reaction took place when tetrasubstituted allene
1g was used (Figure 1).12 The reaction of 1h gave a complex
mixture.
Np
10 mol% DPPM
·
OH
1.2 equiv K2CO3
+
ð4Þ
Np Br
2a
R'
dioxane, reflux
R'
R
R
(1.2 equiv)
1j R = nPr, R' = nBu
1k R = Ph, R' = Me
9a R = nPr, 4.5 h 88%
9b R = Ph, 7 h 44%
The stereoselective formation of the E isomers is rational-
ized as follows (Scheme 5). Upon the palladium-mediated
retro-allylation reaction of 1i, a chair-like transition state
10a with the methyl group at the pseudoequatorial position
would be the most favorable, compared to other possible
transition states including another chair transition state 10b
having a pseudoaxial methyl group.13 Formation of (E)-11
would be thus favored. Intermediate (E)-11 would undergo
smooth reductive elimination to provide (E)-8 exclusively.
We excluded the possibility of the isomerization of (Z)-8
into (E)-8 in situ by a control experiment: exposure of (Z)-12
to the reaction conditions gave rise to no observable isomer-
ization (eq 5).
5 mol% Pd(OAc)2
nC5H11
Np Br 2a
20 mol% (4-FC6H4)3P
1.4 equiv Cs2CO3
Ar
+
nC5H11
·
ð3Þ
OH
dioxane, reflux, 9 h
7 67%
(E/Z = 78:22)
nPr
nPr
1f
(1.2 equiv)
Allenyl alcohol 1i,12 bearing a branched methyl group at the
carbon next to the hydroxylated carbon, reacted with various
aryl bromides to yield (E)-2-aryl-1,3-pentadienes 8 stereo-
selectively (Table 6). No Z isomers were observed. In the event
the Diels-Alder dimerization of 8 is problematic, N-methyl-

J. Imoto et al.
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
397
3-methylethyl-5-hexen-3-ol (3.75 g, 24.0 mmol) in dichloro-
methane (24 mL) was added. The resulting mixture was stirred at
reflux for 12 h. The mixture was cooled to room temperature. After
water (25 mL) was added, the mixture was filtered through a pad of
Celite. The product was extracted with ethyl acetate (30 mL © 3),
and the combined organic phase was dried over anhydrous sodium
sulfate. After evaporation, chromatographic purification on silica
gel (hexane/ethyl acetate = 10:1) provided 3-(2,2-dibromocyclo-
propyl)methyl-2,4-dimethylpentan-3-ol (5.83 g, 17.8 mmol, 74%)
as a pale brown oil.
Magnesium (1.30 g, 53.4 mmol) was placed in a 100-mL
reaction flask. Bromoethane (3.32 mL, 44.5 mmol) in THF
(41.0 mL) was added dropwise at room temperature under argon.
Ethylmagnesium bromide thus obtained was transferred to a
300-mL reaction flask. A solution of 3-(2,2-dibromocyclopropyl)-
methyl-2,4-dimethylpentan-3-ol (5.83 g, 17.8 mmol) in THF
(36.0 mL) was added dropwise at 0 °C. After the addition was
completed, the mixture was stirred for 2 h at ambient temperature.
After a saturated ammonium chloride solution (20 mL) was added,
the product was extracted with ethyl acetate. Concentration
followed by purification on silica gel (hexane/ethyl acetate =
10:1) yielded 2-methyl-3-methylethyl-5,6-heptadien-3-ol (1a,
2.43 g, 14.4 mmol, 81%) as a colorless oil.
5 mol% Pd(OAc)2
10 mol% DPPM
1.4 equiv K2CO3
Ph nC6H13
Ph
ð5Þ
nC6H13
(E)-12 not detected
dioxane, reflux, 5 h
(Z)-12
Conclusion
We have developed a method for the synthesis of 2-aryl-1,3-
alkadienes: palladium-catalyzed 1-methylene-2-propenylation
reactions of aryl bromides with 3,4-alkadien-1-ols. Palladium-
mediated retro-allylation allows 3,4-alkadien-1-ols to act as
1-methylene-2-propenyl metals. The alcohols are practically
inert under air and readily available. Stereoselective synthesis
of (E)-2-aryl-1,3-pentadienes highlights the synthetic advant-
age of the present strategy.
Experimental
1H NMR (500 MHz) and 13C NMR (125.7 MHz)
General.
spectra were taken on a Varian UNITY INOVA 500 spectrometer
and were recorded in CDCl3. Chemical shifts (¤) are in parts per
million relative to tetramethylsilane at 0.00 ppm for 1H and relative
to CDCl3 at 77.2 ppm for 13C unless otherwise noted. IR spectra
were determined on a SHIMADZU FTIR-8200PC spectrometer.
Mass spectra (EI unless otherwise noted) were determined on a
JEOL Mstation 700 spectrometer. TLC analyses were performed
on commercial glass plates bearing a 0.25-mm layer of Merck
Silica gel 60F254. Silica gel (Wakogel 200 mesh) was used for
column chromatography. Elemental analyses were carried out at
the Elemental Analysis Center of Kyoto University.
Unless otherwise noted, materials obtained from commercial
suppliers were used without further purification. Toluene, 1,4-
dioxane, and benzene were stored over slices of sodium. DMF and
DMSO were distilled from calcium hydride prior to use. Cesium
carbonate (standard particle size), potassium carbonate, sodium
carbonate, and potassium phosphate were purchased from Wako
Pure Chemical Co. Finely milled cesium carbonate was obtained
from Chemetall and was stored and handled under inert at-
mosphere. DPPM and tri(4-fluorophenyl)phosphine were pur-
chased from Wako Pure Chemical and Aldrich, respectively.
Palladium acetate and N-methylpyrrole were obtained from TCI.
All reactions were carried out under argon atmosphere. Allenyl
alcohols 1 were synthesized as described in the following.
Typical Procedure for the Preparation of Allenyl Alcohols
1a-1d, 1i, and 1k. Synthesis of 1a is representative. Allyl-
magnesium chloride was prepared from magnesium (0.875 g,
36.0 mmol) and allyl chloride (2.44 mL, 30.0 mmol) in THF
(27 mL) under argon at 0 °C. The Grignard reagent obtained was
placed in a 100-mL reaction flask under argon. A solution of 2,4-
dimethyl-3-pentanone (3.54 mL, 25 mmol) in THF (25 mL) was
added dropwise to the Grignard reagent at 0 °C. The resulting
mixture was stirred for 1 h at room temperature. The reaction was
quenched with 1 M hydrochloric acid (30 mL). Extractive workup
followed by silica gel column purification (hexane/ethyl acetate =
10:1) afforded 2-methyl-3-methylethyl-5-hexen-3-ol (3.75 g, 24.0
mmol, 96%) as a colorless oil.
Typical Procedure for the Preparation of Allenyl Alcohols
1e-1h and 1j.
Synthesis of 1e is representative. A 100-mL
reaction flask, equipped with a Dean-Stark trap was charged with
argon. To this flask, 2-methyl-3-butyn-2-ol (2.91 mL, 30.0 mmol),
triethyl orthoacetate (32.8 mL, 180 mmol), and propionic acid
(0.34 mL, 4.5 mmol) were sequentially added dropwise. The
resulting mixture was heated at reflux (bath temp. 150 °C) for
10 h. After being cooled to ambient temperature, the mixture was
diluted with ether (30 mL). The organic phase was washed with
1 M sulfuric acid (180 mL © 2), a saturated sodium hydrogencar-
bonate solution (100 mL), and brine (50 mL). The residue was
purified on silica gel (hexane/ethyl acetate = 20:1) to give ethyl 5-
methyl-3,4-hexadienoate (2.28 g, 14.8 mmol, 49%) as a yellow oil.
A 100-mL reaction flask was charged with propylmagnesium
bromide prepared from magnesium (0.95 g, 39 mmol) and 1-
bromopropane (2.96 mL, 32.6 mmol) in THF (30 mL). Ethyl 5-
methyl-3,4-hexadienoate (2.28 g, 14.8 mmol) in THF (30 mL) was
added dropwise to the mixture at 0 °C. The resulting mixture was
stirred for 5.5 h at room temperature. The reaction was quenched
with a saturated ammonium chloride solution (10 mL). Extractive
workup and silica gel column purification (hexane/ethyl acetate =
20:1) yielded 8-methyl-4-propyl-6,7-nonadien-4-ol (2.27 g, 11.5
mmol, 78%) as a pale yellow oil.
Typical Procedure for the Palladium-Catalyzed Reactions of
Aryl Bromides 2 with Allenyl Alcohols 1 in the Absence of
N-Methylpyrrole.
The reaction of 1-bromonaphthalene (2a)
with 1a (Table 3, Entry 2) is representative. Potassium carbonate
(80 mg, 0.58 mmol) was placed in a 30-mL reaction flask equipped
with a Dimroth condenser. The base was dried in vacuo with a hair
dryer for 2 min. Under an atmosphere of argon, palladium acetate
(4.5 mg, 0.020 mmol) and DPPM (15.4 mg, 0.040 mmol) were
added to the flask. Dioxane (2.4 mL), alkadienol 1a (80.8 mg,
0.48 mmol), and 1-bromonaphthalene (2a, 93.2 mg, 0.40 mmol)
were sequentially added. The whole mixture was heated at reflux
for 6 h. After the mixture was cooled to room temperature, water
(20 mL) was added. The product was extracted with hexane
(20 mL © 3). The combined organic layer was dried over anhy-
drous sodium sulfate and was concentrated under reduced pressure.
Chromatographic purification (hexane/ethyl acetate = 80:1) yield-
Tetrabutylammonium bromide (0.774 g, 2.4 mmol) was placed
in a 100-mL reaction flask equipped with a Dimroth condenser
under argon. Potassium hydroxide (50 wt % aqueous solution,
24.0 mL, 0.34 mol) and bromoform (10.5 mL, 0.12 mol) were
added at 0 °C. After the mixture was stirred for 10 min, 2-methyl-

398
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
Pd-Catalyzed 1-Methylene-2-propenylation
¹1
ed 1-(1-methylene-2-propenyl)naphthalene (3a, 57 mg, 0.32 mmol,
79%).
3475, 2959, 2874, 1956, 1458, 1379, 1126, 961, 840 cm ;
1H NMR (CDCl3): ¤ 0.91-0.94 (m, 6H), 1.02 (d, J = 7.0 Hz, 3H),
1.25 (s, 1H), 1.27-1.51 (m, 8H), 2.31-2.38 (m, 1H), 4.70 (dt,
J = 6.5, 2.5 Hz, 2H), 5.18 (dt, J = 8.5, 6.5 Hz, 1H); 13C NMR
(CDCl3): ¤ 14.59, 14.98, 15.01, 16.74, 16.79, 38.62, 39.53, 40.74,
75.23, 76.12, 92.04, 208.77; HRMS Found: m/z 182.1668. Calcd
for C12H22O: 182.1671.
Typical Procedure for the Palladium-Catalyzed Reactions in
the Presence of N-Methylpyrrole. The reaction of 4-bromo-
biphenyl (2e) with 1a (Scheme 3) is representative. Potassium
carbonate (66 mg, 0.48 mmol) was placed in a 30-mL reaction flask
and was dried in vacuo. Palladium acetate (4.5 mg, 0.020 mmol)
and DPPM (15.4 mg, 0.040 mmol) were then added under argon.
Dioxane (4 mL), alkadienol 1a (80.8 mg, 0.48 mmol), 4-bromobi-
phenyl (2e, 93.2 mg, 0.40 mmol), and N-methylpyrrole (0.043 mL,
0.48 mmol) were sequentially added. The whole mixture was
heated at reflux for 9 h. After the mixture was cooled to room
temperature, water (20 mL) was added. The product was extracted
with hexane (20 mL © 3). The combined organic layer was dried
and concentrated. The residual oil was purified on silica gel
with hexane as an eluent to afford 1-(1-methylene-2-propenyl)-4-
phenylbenzene (3e, 61.9 mg, 0.30 mmol, 75%). As an exception,
the reaction of 2h with 1a was performed in 2.4 mL of dioxane
(Scheme 3).
5-Butyl-4-propyl-1,2-nonadien-5-ol (1j):
Oil. IR (neat):
3446, 2936, 1956, 1456, 1379, 997, 837 cm¹1; H NMR (CDCl3):
¤ 0.87-0.95 (m, 9H), 1.20-1.36 (m, 10H), 1.41-1.52 (m, 6H), 1.47
(s, 1H), 2.17 (t, J = 10.0 Hz, 1H), 4.67 (dd, J = 6.5, 1.5 Hz, 2H),
4.96 (dt, J = 10.0, 6.5 Hz, 1H); 13C NMR (CDCl3): ¤ 14.30, 14.37
(2 peaks merge), 21.56, 23.63, 23.66, 25.62 (2 peaks merge),
31.17, 36.56, 36.85, 47.63, 74.32, 76.27, 90.29, 209.52; HRMS
Found: m/z 237.2218. Calcd for C16H30O [M+ ¹ H]: 237.2214.
2-Methyl-3-phenyl-4,5-hexadien-2-ol (1k): Oil. IR (neat):
3447, 2973, 2933, 1956, 1452, 1373, 1198, 1150, 874, 844, 742,
1
702 cm¹1; H NMR (CDCl3): ¤ 1.18 (s, 3H), 1.25 (s, 3H), 1.56 (s,
1
1H), 3.35 (dt, J = 9.5, 1.5 Hz, 1H), 4.69 (ddd, J = 11.0, 6.5,
1.5 Hz, 1H), 4.74 (ddd, J = 11.0, 6.5, 1.5 Hz, 1H), 5.59 (dt, J =
9.5, 6.5 Hz, 1H), 7.25-7.30 (m, 3H), 7.30-7.35 (m, 2H); 13C NMR
(CDCl3): ¤ 27.92, 27.95, 57.25, 73.13, 75.36, 90.27, 127.09,
128.42, 129.38, 140.95, 209.29; Found: C, 82.94; H, 8.85%. Calcd
for C13H16O: C, 82.93; H, 8.57%.
Characterization Data. Spectral data for 1b,14 1c,15 1d,8 3a,8
3c,8 and 6a16 are found in the literature.
2-Methyl-3-methylethyl-5,6-heptadien-3-ol (1a):
(neat): 3490, 2965, 2880, 1956, 1471, 1386, 977, 948, 842 cm
Oil. IR
¹1
;
1H NMR (CDCl3): ¤ 0.93-0.99 (m, 12H), 1.23 (s, 1H), 1.95 (sep,
J = 7.0 Hz, 2H), 2.26 (dd, J = 8.5, 3.0 Hz, 2H), 4.66 (dd, J = 6.5,
3.0 Hz, 2H), 5.08-5.15 (m, 1H); 13C NMR (CDCl3): ¤ 17.52,
17.76, 33.29, 34.23, 74.26, 86.40, 209.93; HRMS Found: m/z
168.1514. Calcd for C11H20O: 168.1514.
1-(1-Methylene-2-propenyl)-2-phenylbenzene (3b): Oil. IR
(neat): 3086, 3058, 3022, 1588, 1479, 1448, 1435, 1009, 989, 905,
¹1
745, 699 cm
;
1H NMR (CDCl3): ¤ 4.81 (d, J = 17.5 Hz, 1H),
5.01-5.05 (m, 1H), 5.02 (d, J = 10.5 Hz, 1H), 5.26-5.29 (m, 1H),
6.41 (dd, J = 17.5, 10.5 Hz, 1H), 7.24-7.41 (m, 9H); 13C NMR
(CDCl3): ¤ 117.31, 120.11, 126.85, 127.10, 127.77, 127.94,
129.14, 130.28, 130.68, 138.34, 139.00, 141.24, 142.04, 148.31;
Found: C, 93.20; H, 7.00%. Calcd for C16H14: C, 93.16; H, 6.84%.
8-Methyl-4-propyl-6,7-nonadien-4-ol (1e):
3389, 2958, 2873, 1969, 1454, 1233, 1134, 1021, 862, 822 cm
Oil. IR (neat):
¹1
;
1H NMR (CDCl3): ¤ 0.91 (t, J = 7.5 Hz, 6H), 1.28-1.37 (m, 4H),
1.41-1.46 (m, 4H), 1.42 (s, 1H), 1.68 (d, J = 3.0 Hz, 6H), 2.09
(d, J = 8.0 Hz, 2H), 4.92 (tsep, J = 8.0, 3.0 Hz, 1H); 13C NMR
(CDCl3): ¤ 14.94, 17.00, 20.79, 39.64, 41.59, 74.58, 83.94, 94.56,
203.90; Found: C, 79.65; H, 12.47%. Calcd for C13H24O: C, 79.53;
H, 12.32%.
Ethyl 4-(1-Methylene-2-propenyl)benzoate (3d):
Oil. IR
(neat): 2981, 1719, 1609, 1367, 1275, 1178, 1103, 1020, 907, 863,
781, 715 cm¹1; 1H NMR (CDCl3): ¤ 1.40 (t, J = 7.0 Hz, 3H), 4.39
(q, J = 7.0 Hz, 2H), 5.15 (d, J = 17.5 Hz, 1H), 5.23 (d, J = 10.0
Hz, 1H), 5.24-5.27 (m, 1H), 5.35-5.38 (m, 1H), 6.62 (dd,
J = 17.5, 10.0 Hz, 1H), 7.37-7.40 (m, 2H), 8.01-8.04 (m, 2H);
13C NMR (CDCl3): ¤ 14.58, 61.16, 117.76, 118.05, 128.47,
129.66, 129.80, 137.82, 144.57, 147.71, 166.71; Found: C,
77.01; H, 6.80%. Calcd for C13H14O2: C, 77.20; H, 6.98%.
1-(1-Methylene-2-propenyl)-4-phenylbenzene (3e): Solid. IR
(nujol): 2924, 2855, 1577, 1485, 1448, 996, 928, 906, 842, 773,
4-Propyl-6,7-tridecadien-4-ol (1f): Oil. IR (neat): 3390, 2958,
¹1
2932, 2873, 1962, 1458, 1378, 1132, 977, 874 cm
;
1H NMR
(CDCl3): ¤ 0.89 (t, J = 7.0 Hz, 3H), 0.92 (t, J = 7.0 Hz, 6H), 1.27-
1.36 (m, 8H), 1.38-1.47 (m, 6H), 1.40 (s, 1H), 1.95-2.01 (m,
2H), 2.11-2.15 (m, 2H), 5.02-5.11 (m, 2H); 13C NMR (CDCl3): ¤
14.31, 14.92 (2 peaks merge), 16.98, 17.03, 22.72, 29.09, 29.16,
31.56, 39.65, 41.52, 41.68, 74.60, 85.94, 90.62, 205.82; Found: C,
80.34; H, 12.89%. Calcd for C16H30O: C, 80.61; H, 12.68%.
740 cm¹1; H NMR (CDCl3): ¤ 5.25 (d, J = 10.5 Hz, 1H), 5.26-
1
5-Butyl-7-(2-methyl-1-propenylidene)tridecan-5-ol
Oil. IR (neat): 3446, 2931, 2360, 1456, 1379, 1135, 1059 cm
(1g):
5.28 (m, 1H), 5.27 (d, J = 17.5 Hz, 1H), 5.32-5.35 (m, 1H), 6.65
(dd, J = 17.5, 10.5 Hz, 1H), 7.33-7.38 (m, 1H), 7.39-7.48 (m,
4H), 7.57-7.64 (m, 4H); 13C NMR (CDCl3): ¤ 117.06, 117.47,
127.08, 127.27, 127.51, 128.86, 128.99, 138.26, 138.90, 140.57,
141.04, 147.99; HRMS Found: m/z 206.1093. Calcd for C16H14:
206.1096. mp: 48.2-49.1 °C.
1-[4-(1-Methylene-2-propenyl)phenyl]ethanone (3f): Oil. IR
(neat): 3090, 1684, 1605, 1401, 1358, 1267, 1016, 992, 957, 907,
848 cm¹1; 1H NMR (CDCl3): ¤ 2.62 (s, 3H), 5.16 (d, J = 17.0 Hz,
1H), 5.25 (d, J = 11.0 Hz, 1H), 5.26 (s, 1H), 5.38 (s, 1H), 6.62 (dd,
J = 17.0, 11.0 Hz, 1H), 7.40-7.44 (m, 2H), 7.93-7.97 (m, 2H);
13C NMR (CDCl3): ¤ 26.87, 117.82, 118.18, 128.50, 128.70,
136.44, 137.73, 144.88, 147.57, 198.01; Found: C, 83.47; H,
6.94%. Calcd for C12H12O: C, 83.69; H, 7.02%.
¹1
;
1H NMR (CDCl3): ¤ 0.86-0.93 (m, 9H), 1.22-1.33 (m, 14H), 1.33-
1.40 (m, 2H), 1.43-1.51 (m, 4H), 1.57 (s, 1H), 1.68 (s, 6H), 1.92 (t,
J = 7.0 Hz, 2H), 2.05 (s, 2H); 13C NMR (CDCl3): ¤ 14.33 (2 peaks
merge), 14.36, 21.03 (2 peaks merge), 22.92, 23.64 (2 peaks
merge), 26.22 (2 peaks merge), 27.85, 29.11, 32.07, 35.20, 38.91
(2 peaks merge), 42.29, 74.86, 96.25, 98.34, 199.60; Found: C,
81.48; H, 13.17%. Calcd for C21H40O: C, 81.75; H, 13.07%.
5-Butyl-7-vinylidenetridecan-5-ol (1h): Oil. IR (neat): 3447,
2859, 1954, 1456, 1379, 841 cm¹1; 1H NMR (CDCl3): ¤ 0.86-0.93
(m, 9H), 1.22-1.35 (m, 14H), 1.38-1.45 (m, 2H), 1.46-1.51 (m,
4H), 1.76 (s, 1H), 1.98 (tt, J = 7.5, 3.5 Hz, 2H), 2.11 (t, J = 2.5 Hz,
2H), 4.70 (tt, J = 3.5, 2.5 Hz, 2H); 13C NMR (CDCl3): ¤ 14.33 (2
peaks merge), 22.86, 23.52, 26.14, 27.81, 29.17, 31.95, 34.20,
39.03, 42.07, 75.47, 75.86, 99.88, 207.29; HRMS Found: m/z
280.2765. Calcd for C19H36O: 280.2766.
4-(1-Methylene-2-propenyl)benzaldehyde (3g):
Oil. IR
(neat): 2833, 1699, 1606, 1589, 1565, 1387, 1305, 1210, 1170,
¹1
992, 909, 838 cm
1H), 5.26 (d, J = 10.5 Hz, 1H), 5.27-5.30 (m, 1H), 5.39-5.42 (m,
;
1H NMR (CDCl3): ¤ 5.16 (d, J = 17.5 Hz,
5-Methyl-4-propyl-6,7-octadien-4-ol (1i):
Oil. IR (neat):

J. Imoto et al.
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
399
1H), 6.63 (dd, J = 17.5, 10.5 Hz, 1H), 7.48-7.51 (m, 2H), 7.86-
7.90 (m, 2H), 10.03 (s, 1H); 13C NMR (CDCl3): ¤ 117.97, 118.53,
129.15, 129.89, 135.76, 137.61, 146.33, 147.48, 192.17; HRMS
Found: m/z 158.0729. Calcd for C11H10O: 158.0732.
2-[4-(1-Methylene-2-propenyl)phenyl]-1,3-dioxolane (3h):
Oil. IR (neat): 3089, 2954, 2885, 1588, 1417, 1385, 1222, 1082,
1019, 943, 906, 836 cm¹1; 1H NMR (CDCl3): ¤ 4.02-4.09 (m, 2H),
4.12-4.19 (m, 2H), 5.17 (d, J = 16.0 Hz, 1H), 5.18-5.22 (m, 1H),
5.21 (d, J = 11.0 Hz, 1H), 5.29-5.32 (m, 1H), 5.83 (s, 1H), 6.61
(dd, J = 16.0, 11.0 Hz, 1H), 7.32-7.36 (m, 2H), 7.45-7.49 (m,
2H); 13C NMR (CDCl3): ¤ 65.58, 103.84, 117.45, 117.52, 126.48,
128.59, 137.22, 138.20, 140.93, 148.11; Found: C, 77.10; H,
7.06%. Calcd for C13H14O2: C, 77.20; H, 6.98%.
5.08 (d, J = 1.5 Hz, 1H), 5.17 (dq, J = 15.5, 6.5 Hz, 1H), 5.45 (dd,
J = 1.5, 1.0 Hz, 1H), 6.47 (dd, J = 15.5, 1.0 Hz, 1H), 7.29-7.32
(m, 1H), 7.40-7.48 (m, 3H), 7.78-7.82 (m, 1H), 7.83-7.86 (m,
1H), 7.89-7.93 (m, 1H); 13C NMR (CDCl3): ¤ 18.34, 116.89,
125.52, 125.81, 125.86, 126.64, 126.66, 127.61, 128.24, 130.08,
132.08, 133.66, 134.19, 139.06, 147.39; Found: C, 92.61; H,
7.39%. Calcd for C15H14: C, 92.74; H, 7.26%.
(E)-1-(Methylene-2-butenyl)-2-phenylbenzene (8b): Oil. IR
(neat): 3059, 3021, 1599, 1478, 1448, 1435, 1009, 965, 890, 769,
745, 699 cm¹1; 1H NMR (CDCl3): ¤ 1.61 (dd, J = 6.5, 1.5 Hz, 3H),
4.85 (d, J = 1.5 Hz, 1H), 5.11 (dd, J = 1.5, 1.5 Hz, 1H), 5.28 (dq,
J = 15.5, 6.5 Hz, 1H), 6.09 (dd, J = 15.5, 1.5 Hz, 1H), 7.23-7.38
(m, 9H); 13C NMR (CDCl3): ¤ 18.21, 117.15, 126.81, 127.03,
127.57, 127.87, 129.06, 129.54, 130.19, 130.60, 133.65, 139.45,
141.17, 142.18, 148.11; Found: C, 92.46; H, 7.46%. Calcd for
C17H16: C, 92.68; H, 7.32%.
1-(2-Methyl-1-vinyl-1-propenyl)-4-phenylbenzene (6b): Oil.
IR (neat): 3027, 2910, 1601, 1486, 1448, 1009, 986, 903, 837, 769,
1
738, 697 cm¹1; H NMR (CDCl3): ¤ 1.63 (s, 3H), 1.99 (s, 3H),
4.60 (d, J = 17.0 Hz, 1H), 5.02 (d, J = 11.0 Hz, 1H), 7.01 (dd,
J = 17.0, 11.0 Hz, 1H), 7.12-7.16 (m, 2H), 7.32-7.37 (m, 1H),
7.42-7.48 (m, 2H), 7.57-7.61 (m, 2H), 7.62-7.66 (m, 2H);
13C NMR (CDCl3): ¤ 20.15, 23.39, 115.18, 126.92, 127.21,
127.29, 128.94, 130.70, 133.35, 135.39, 135.85, 139.18, 139.73,
141.27; Found: C, 92.07; H, 7.96%. Calcd for C18H18: C, 92.26; H,
7.74%.
Ethyl 4-(2-Methyl-1-vinyl-1-propenyl)benzoate (6c): Oil. IR
(neat): 2983, 2909, 1718, 1608, 1367, 1272, 1176, 1098, 1022,
777, 719 cm¹1; 1H NMR (CDCl3): ¤ 1.40 (t, J = 7.0 Hz, 3H), 1.55
(s, 3H), 1.97 (s, 3H), 4.39 (q, J = 7.0 Hz, 2H), 4.45 (d,
J = 17.0 Hz, 1H), 5.00 (d, J = 7.0 Hz, 1H), 6.96 (dd, J = 17.0,
10.5 Hz, 1H), 7.13-7.15 (m, 2H), 8.01-8.05 (m, 2H); 13C NMR
(CDCl3): ¤ 14.59, 20.12, 23.23, 61.07, 115.36, 128.81, 129.60,
130.38, 133.65, 135.11, 135.42, 145.90, 166.95; Found: C, 78.29;
H, 7.96%. Calcd for C15H18O2: C, 78.23; H, 7.88%.
(E)-1-Methoxy-4-(1-methylene-2-butenyl)benzene (8c): Oil.
IR (neat): 2934, 2912, 2835, 1609, 1511, 1442, 1286, 1246, 1178,
1
1036, 969, 886, 836 cm¹1; H NMR (CDCl3): ¤ 1.78 (dd, J = 6.5,
1.5 Hz, 3H), 3.82 (s, 3H), 5.01 (d, J = 1.5 Hz, 1H), 5.11 (d, J =
1.5 Hz, 1H), 5.68 (dq, J = 15.5, 6.5 Hz, 1H), 6.30 (d, J = 15.5 Hz,
1H), 6.86-6.89 (m, 2H), 7.23-7.27 (m, 2H); 13C NMR (CDCl3): ¤
18.47, 55.48, 113.63, 113.74, 129.12, 129.50, 133.10, 133.35,
147.73, 159.16; Found: C, 82.62; H, 8.24%. Calcd for C12H14O: C,
82.72; H, 8.10%.
Ethyl (E)-4-(1-Methylene-2-butenyl)benzoate (8d): Oil. IR
(neat): 2981, 1718, 1610, 1404, 1367, 1273, 1176, 1128, 1103,
1
1020, 967, 863, 781, 717 cm¹1; H NMR (CDCl3): ¤ 1.40 (t, J =
7.0 Hz, 3H), 1.79 (dd, J = 6.5, 1.5 Hz, 3H), 4.38 (q, J = 7.0 Hz,
2H), 5.08 (m, 1H), 5.22 (m, 1H), 5.63 (dq, J = 16.0, 6.5 Hz, 1H),
6.31 (dd, J = 16.0, 1.0 Hz, 1H), 7.35-7.39 (m, 2H), 8.00-8.03 (m,
2H); 13C NMR (CDCl3): ¤ 14.58, 18.52, 61.13, 115.47, 128.44,
129.57, 129.60, 129.80, 132.39, 145.60, 147.59, 166.74; HRMS
Found: m/z 216.1150. Calcd for C14H16O2: 216.1150.
1-Methoxy-4-(2-methyl-1-vinyl-1-propenyl)benzene
(6d):
Oil. IR (neat): 2909, 2834, 1609, 1511, 1285, 1243, 1174, 1104,
1
1038, 903, 830 cm¹1; H NMR (CDCl3): ¤ 1.58 (s, 3H), 1.95 (s,
(E)-1-(1-Methylene-2-butenyl)-4-phenylbenzene (8e): Oil.
IR (neat): 2924, 2853, 1486, 1443, 1007, 978, 890, 851, 772, 741,
699 cm¹1; 1H NMR (CDCl3): ¤ 1.81 (dd, J = 7.0, 2.0 Hz, 3H), 5.11
(m, 1H), 5.19-5.22 (m, 1H), 5.74 (dq, J = 15.5, 7.0 Hz, 1H), 6.35
(dd, J = 15.5, 2.0 Hz, 1H), 7.33-7.37 (m, 1H), 7.38-7.42 (m, 2H),
7.42-7.47 (m, 2H), 7.56-7.59 (m, 2H), 7.60-7.63 (m, 2H);
13C NMR (CDCl3): ¤ 18.52, 114.55, 127.00, 127.27, 127.46,
128.86, 128.99, 129.42, 132.81, 139.92, 140.41, 141.11, 147.90;
HRMS Found: m/z 220.1252. Calcd for C17H16: 220.1252.
(E)-1-[4-(1-Methylene-2-butenyl)phenyl]ethanone (8f): Oil.
IR (neat): 2931, 2855, 1683, 1602, 1407, 1358, 1269, 1015, 958,
827 cm¹1; 1H NMR (CDCl3): ¤ 1.79 (dd, J = 7.0, 2.0 Hz, 3H), 2.61
(s, 3H), 5.09 (m, 1H), 5.23 (m, 1H), 5.62 (dq, J = 15.5, 7.0 Hz,
1H), 6.32 (dd, J = 15.5, 2.0 Hz, 1H), 7.38-7.42 (m, 2H), 7.92-7.95
(m, 2H); 13C NMR (CDCl3): ¤ 18.53, 26.86, 115.61, 128.42,
128.68, 129.87, 132.31, 136.28, 145.93, 147.46, 198.02; HRMS
Found: m/z 186.1044. Calcd for C13H14O: 186.1045.
3H), 3.83 (s, 3H), 4.54 (dd, J = 17.0, 1.5 Hz, 1H), 4.99 (dd,
J = 10.5, 1.5 Hz, 1H), 6.87-6.91 (m, 2H), 6.96-6.99 (m, 2H), 6.98
(dd, J = 17.0, 10.5 Hz, 1H); 13C NMR (CDCl3): ¤ 20.10, 23.31,
55.39, 113.60, 114.92, 131.26, 132.88, 133.27, 135.26, 136.15,
158.18; Found: C, 82.69; H, 8.64%. Calcd for C13H16O: C, 82.93;
H, 8.57%.
1-(1-Vinyl-1-heptenyl)naphthalene (E:Z = 78:22 Mixture)
(7): Oil. IR (neat): 3044, 2956, 2926, 2856, 1593, 1507, 987,
¹1
906, 800, 779 cm
;
1H NMR (CDCl3): ¤ 0.78 (t, J = 7.0 Hz,
0.78 © 3H), 0.93 (t, J = 7.0 Hz, 0.22 © 3H), 1.08-1.18 (m, 0.78 ©
4H), 1.26-1.34 (m, 0.78 © 2H), 1.35-1.44 (m, 0.22 © 4H), 1.49-
1.57 (m, 0.22 © 2H), 1.76 (q, J = 7.5 Hz, 0.78 © 2H), 2.44 (q,
J = 7.5 Hz, 0.22 © 2H), 4.41 (d, J = 7.5 Hz, 0.78 © 1H), 4.61 (d,
J = 17.5 Hz, 0.22 © 1H), 4.92 (d, J = 11.0 Hz, 0.78 © 1H), 5.08-
5.13 (m, 0.22 © 1H), 5.61 (t, J = 7.5 Hz, 0.22 © 1H), 6.00 (t,
J = 7.5 Hz, 0.78 © 1H), 6.70 (dd, J = 17.5, 11.0 Hz, 0.78 © 1H),
7.06 (dd, J = 17.5, 10.5 Hz, 0.22 © 1H), 7.20-7.24 (m, 0.78 © 1H),
7.27-7.30 (m, 0.22 © 1H), 7.39-7.52 (m, 3H), 7.76-7.88 (m, 3H);
13C NMR (CDCl3): ¤ 14.14, 14.33, 22.62, 22.80, 28.02, 29.22,
29.43, 29.62, 31.56, 31.79, 114.62, 117.38, 125.61, 125.63, 125.69,
125.72, 125.85, 125.93, 126.25, 126.71, 127.24, 127.26, 127.41,
127.43, 128.26, 128.33, 132.11, 132.56, 133.70, 133.71, 133.78,
135.15, 136.05, 136.15, 138.46, 139.85, 139.89, 140.80; Found: C,
91.35; H, 9.02%. Calcd for C19H22: C, 91.14; H, 8.86%.
(E)-4-(1-Methylene-2-butenyl)benzaldehyde (8g):
Oil. IR
(neat): 2914, 1699, 1606, 1564, 1386, 1304, 1210, 1169, 968, 896,
840, 757, 723 cm¹1; 1H NMR (CDCl3): ¤ 1.79 (dd, J = 7.0, 2.0 Hz,
3H), 5.11 (m, 1H), 5.26 (m, 1H), 5.62 (dq, J = 15.5, 7.0 Hz, 1H),
6.32 (dd, J = 15.5, 2.0 Hz, 1H), 7.46-7.49 (m, 2H), 7.84-7.87 (m,
2H), 10.0 (s, 1H); 13C NMR (CDCl3): ¤ 18.55, 115.94, 129.12,
129.82, 130.02, 132.18, 135.62, 147.35, 147.39, 192.19; HRMS
Found: m/z 172.0888. Calcd for C12H12O: 172.0888.
(E)-1-(1-Methylene-2-butenyl)naphthalene (8a):
(neat): 3016, 2911, 2851, 1591, 1504, 1448, 1436, 1255, 964, 894,
802, 778 cm¹1; 1H NMR (CDCl3): ¤ 1.68 (dd, J = 6.5, 1.0 Hz, 3H),
Oil. IR
(E)-2-[4-(1-Methylene-2-butenyl)phenyl]-1,3-dioxolane (8h):
Oil. IR (neat): 2882, 1597, 1421, 1387, 1304, 1221, 1080, 1019,
968, 890, 837 cm¹1; 1H NMR (CDCl3): ¤ 1.77 (dd, J = 7.0, 2.0 Hz,

400
Bull. Chem. Soc. Jpn. Vol. 82, No. 3 (2009)
Pd-Catalyzed 1-Methylene-2-propenylation
3H), 4.03-4.09 (m, 2H), 4.12-4.18 (m, 2H), 5.03 (m, 1H), 5.15-
5.18 (m, 1H), 5.63 (dq, J = 15.5, 7.0 Hz, 1H), 5.83 (s, 1H), 6.31
(dd, J = 15.5, 2.0 Hz, 1H), 7.31-7.34 (m, 2H), 7.44-7.47 (m, 2H);
13C NMR (CDCl3): ¤ 18.48, 65.57, 103.87, 114.84, 126.37,
128.57, 129.57, 132.78, 137.01, 141.95, 148.01; Found: C,
77.46; H, 7.54%. Calcd for C14H16O2: C, 77.75; H, 7.46%.
Shimono, T. Hiyama, Chem. Lett. 2004, 33, 1066.
a) S. Hayashi, K. Hirano, H. Yorimitsu, K. Oshima, J. Am.
4
Chem. Soc. 2006, 128, 2210. b) M. Iwasaki, S. Hayashi, K. Hirano,
H. Yorimitsu, K. Oshima, J. Am. Chem. Soc. 2007, 129, 4463.
c) M. Iwasaki, S. Hayashi, K. Hirano, H. Yorimitsu, K. Oshima,
Tetrahedron 2007, 63, 5200. d) S. Hayashi, K. Hirano, H.
Yorimitsu, K. Oshima, J. Am. Chem. Soc. 2007, 129, 12650. e) S.
Hayashi, K. Hirano, H. Yorimitsu, K. Oshima, J. Am. Chem. Soc.
2008, 130, 5048. f) H. Yorimitsu, K. Oshima, J. Synth. Org.
Chem., Jpn. 2008, 66, 332.
(E)-1-(1-Methylene-2-hexenyl)naphthalene (9a):
Oil. IR
(neat): 3044, 2958, 2928, 2871, 967, 893, 802, 779 cm¹1; 1H NMR
(CDCl3): ¤ 0.81 (t, J = 7.5 Hz, 3H), 1.29 (tq, J = 7.5, 7.5 Hz, 2H),
2.00 (dt, J = 7.5, 7.5 Hz, 2H), 5.10 (d, J = 2.5 Hz, 1H), 5.16 (dt,
J = 15.5, 7.5 Hz, 1H), 5.46 (d, J = 2.5 Hz, 1H), 6.45 (d,
J = 15.5 Hz, 1H), 7.30-7.33 (m, 1H), 7.40-7.49 (m, 3H), 7.79-
7.82 (m, 1H), 7.83-7.87 (m, 1H), 7.90-7.94 (m, 1H); 13C NMR
(CDCl3): ¤ 13.87, 22.36, 34.93, 117.11, 125.54, 125.78, 125.80,
126.65, 126.74, 127.60, 128.21, 132.09, 132.95, 133.66, 135.36,
139.11, 147.51; Found: C, 91.94; H, 8.35%. Calcd for C17H18: C,
91.84; H, 8.16%.
5
Reviews for palladium-catalyzed C-C bond cleavage of
tertiary alcohols: a) J. Muzart, Tetrahedron 2005, 61, 9423. b) T.
Nishimura, S. Uemura, Synlett 2004, 201. c) M. Miura, T. Satoh,
Top. Organomet. Chem. 2005, 14, 1.
6
Cross-coupling reactions of organic halides with tertiary
alcohols via ¢-carbon elimination: a) M. Nakano, T. Satoh, M.
Miura, J. Org. Chem. 2006, 71, 8309. b) Y. Terao, H. Wakui, T.
Satoh, M. Miura, M. Nomura, J. Am. Chem. Soc. 2001, 123,
10407. c) T. Nishimura, S. Uemura, J. Am. Chem. Soc. 1999, 121,
11010. d) R. C. Larock, C. K. Reddy, Org. Lett. 2000, 2, 3325.
e) H.-F. Chow, C.-W. Wan, K.-H. Low, Y.-Y. Yeung, J. Org. Chem.
2001, 66, 1910.
(E)-1-[1-Methylene-3-phenyl-2-propenyl]naphthalene (9b):
Solid. IR (nujol): 2923, 2854, 1591, 1578, 1505, 1493, 1454,
1377, 962, 800, 777, 754, 697 cm¹1; 1H NMR (CDCl3): ¤ 5.30 (d,
J = 2.0 Hz, 1H), 5.71 (d, J = 2.0 Hz, 1H), 6.02 (d, J = 16.5 Hz,
1H), 7.16-7.21 (m, 1H), 7.22-7.31 (m, 5H), 7.37-7.45 (m, 2H),
7.45-7.54 (m, 2H), 7.85-7.91 (m, 2H), 7.92-7.96 (m, 1H);
13C NMR (CDCl3): ¤ 120.18, 125.60, 125.96, 126.11, 126.54,
126.74, 126.90, 127.81, 127.94, 128.30, 128.71, 131.60, 132.09,
132.60, 133.72, 137.23, 138.30, 147.32; HRMS Found: m/z
256.1250. Calcd for C20H16: 256.1252. mp: 75.5-76.3 °C.
7
a) M. Lahrech, S. Hacini, J.-L. Parrain, M. Santelli,
Tetrahedron Lett. 1997, 38, 3395. b) M. S. Baird, A. V.
Nizovtsev, I. G. Bolesov, Tetrahedron 2002, 58, 1581.
8
C. H. Oh, S. H. Jung, S. Y. Bang, D. I. Park, Org. Lett.
2002, 4, 3325.
9
Examples of hydroxy-directed Heck reactions: a) M.
Oestreich, F. Sempere-Culler, A. B. Machotta, Angew. Chem.,
Int. Ed. 2005, 44, 149. b) E. Bernocchi, S. Cacchi, P. G. Ciattini, E.
Morera, G. Ortar, Tetrahedron Lett. 1992, 33, 3073.
10 For palladium-catalyzed Diels-Alder reactions wherein
dienes and dienophiles are electronically similar, see: a) M.
Murakami, R. Minamida, K. Itami, M. Sawamura, Y. Ito, Chem.
Commun. 2000, 2293. b) K. Kumar, R. S. Jolly, Tetrahedron Lett.
1998, 39, 3047. Also see: c) M. Lautens, W. Klute, W. Tam, Chem.
Rev. 1996, 96, 49.
This work was supported by Grants-in-Aid for Scientific
Research and GCOE Research from MEXT and JSPS. S.H. and
K.H. thank JSPS for financial support. H.Y. acknowledges
financial support through the Eisai Award of Synthetic Organic
Chemistry, Japan, and from Kyoto University. Finely milled
cesium carbonate was a gift from Chemetall GmbH.
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