Nitroalkenes as carbonyl surrogates in arylmethyl-homoallylic alcohol forming one-pot allylation reactions in water

Article abstract of DOI:10.1021/jo302572s

A simple and practical approach has been developed for conducting direct, homoallylic alcohol forming allylation reactions of nitroalkenes in water. Employing the new method, various arylmethyl-homoallylic alcohols can be produced from the corresponding, readily prepared β-nitrostyrenes.

Full text of DOI:10.1021/jo302572s

Note
pubs.acs.org/joc
Nitroalkenes as Carbonyl Surrogates in Arylmethyl-homoallylic
Alcohol Forming One-Pot Allylation Reactions in Water
Mei-Huey Lin,* Wei-Cheng Lin, Han-Jun Liu, and Tsung-Hsun Chuang
Department of Chemistry, National Changhua University of Education, Changhua, Taiwan 50007
S
* Supporting Information
ABSTRACT: A simple and practical approach has been developed for
conducting direct, homoallylic alcohol forming allylation reactions of
nitroalkenes in water. Employing the new method, various arylmethyl-
homoallylic alcohols can be produced from the corresponding, readily
prepared β-nitrostyrenes.
s a consequence of the fact that it is readily available and
environmentally benign, water has received considerable
Scheme 2
A
attention recently as the solvent of choice for chemical
reactions.1 In particular, metal-mediated C−C bond forming
reactions occurring in aqueous media have been intensively
investigated.2 In addition, nitroalkenes are known to be
excellent Michael acceptors in conjugate addition reactions
with organometallic reagents that are prepared in situ from
allylic bromides and metals.3 The general method for the
conversion of nitroalkenes to carbonyl compounds involves a
stepwise procedure that includes reduction to generate
nitroalkanes followed by the Nef reaction (Scheme 1).4 Only
Scheme 1
a few examples of one-pot conversions of nitroalkenes to
carbonyl compounds, utilizing reductive and oxidative
procedures, have been described.5 Although 2-arylacetalde-
hydes participate in allylation reactions that produce useful
synthetic building blocks,6 substrates of this type have limited
commercially availability and exceptional lability.
scope of reactions in which nitroalkenes serve as substrates in
organotin mediated allylation reactions in water. The results of
this effort show that this process serves as a convenient method
for the synthesis of arylmethyl-homoallylic alcohols.
In previous studies, we have shown that several noncarbonyl
compounds such as enol ethers,7 formalin, and aldoximes
participate in aqueous metal-mediated Barbier type allylation
reactions.9 Apparently, water plays a key role in these processes
by participating in the formation of reactive aldehydes from the
corresponding enol ethers, formalin, or aldoximes, which then
undergo allylation in the presence of allyl anion equivalents. In
water, enol ethers undergo hydration via oxocarbonium ion
intermediates, which readily react with water to form
hemiacetals and finally aldehydes. In contrast, hydration of β-
nitrostyrene that introduces a hydroxyl group at the β-position
only occurs with difficulty under acidic hydrolysis. In addition,
α,β-unsaturated nitroalkenes undergo reduction reactions to
yield oximes when treated with the types of metals or metal
We previously devised a simple method for the preparation
of arylmethyl-homoallylic alcohols starting with β-methoxystyr-
enes,7 which is superior to other more complicated approaches
that utilize styrene oxide or methyl phenylacetate as phenyl-
acetaldehyde equivalents.8 Although β-methoxystyrenes can be
readily prepared by using Wittig olefination reactions of the
corresponding benzaldehydes, large scale production of these
substances requires the use of large amounts of methoxyme-
thyltriphenylphosphonium chloride and moisture-excluding
conditions (Scheme 2). In contrast, β-nitrostyrenes are readily
generated in a large scale manner through nitro-aldol
condensation reactions of benzaldehydes followed by recrystal-
lization. Until now, no reports exist describing the use of
nitroalkenes as surrogates for carbonyl compounds in metal-
mediated Barbier type allylation reactions. In the study
described below, we have explored the potential for and
Received: November 29, 2012
Published: December 26, 2012
© 2012 American Chemical Society
1278
dx.doi.org/10.1021/jo302572s | J. Org. Chem. 2013, 78, 1278−1282

The Journal of Organic Chemistry
Note
salts that are typically employed in Barbier type allylation
reactions.10 These features along with potential polymerization
reactions of β-nitrostyrene are issues of concern in developing
new Barbier type allylation reactions of β-nitrostyrenes.
In our initial investigations, we observed that treatment of β-
nitrostyrene with allyl bromide and various metal combinations
in aqueous solution either failed to generate or gave poor yields
of products.11 An exploratory study of tin mediated allylation
reactions of β-nitrostyrene was then conducted employing allyl
bromide and various in situ generated allylstannane sources
(Table 1). The formation of the allylstannane intermediate in
product in 69% yield (entry 5). In addition, no significant
yield is improved at higher temperature (2a was formed at 55
°C with 62% yield).
Although hydrolytic cleavage of nitroalkenes in strongly
acidic aqueous solution has been described previously,14
formation of the allylation product by reaction of benzaldehyde,
which would be produced from β-nitrostyrene in this way, was
not observed to occur under the optimal conditions (Scheme
3). The fact that high acidity is needed in order for the
Scheme 3
Table 1. Tin-Mediated Allylation Reactions of β-
a
Nitrostyrene
allylation reaction to occur15 suggests that the presence of the
carbon−carbon double bond in the substrate is crucial for the
reaction. In accord with this proposal is the observation that (2-
nitroethyl)benzene does not serve as a substrate for the
allylation reaction (eq 1). Finally, comparison of the rates of
entry
metal/additive
time (h)
yield (%)
1
2
3
Sn
4
4
0
31
0
Sn/TiCl3
SnCl2/TiCl3
Sn/HCl
14
1.5
1.5
1.5
1
b
4
47
69
55
57
53
c
5
Sn/HCl
c
6
c
Sn/HBr
7
Sn/H2SO4
Sn/CF3SO3H
allylation reactions of aldoximes (overnight) vs nitroalkenes
(1.5 h)9b demonstrates that tin-mediated allylation of nitro-
alkenes does not take place through aldoxime intermediates.
The observations described above have led to a proposal of a
plausible mechanism shown in Scheme 4 for the allylation
c
8
1
a
Conditions: 1a (1.0 mmol), allyl bromide (2.0 mmol), and indicated
b
metal (2.0 mmol) in water (2.0 mL) at rt. Conditions: To a
suspension of 1a (1.0 mmol), allyl bromide (2.0 mmol), and tin
powder (2.0 mmol) in water (1.8 mL) at rt, HCl (0.2 mL) was added.
c
Conditions: To a suspension of allyl bromide (2.0 mmol), tin powder
(2.0 mmol), and HCl (0.2 mL) in water (1.8 mL) at rt, 1a (1.0 mmol)
was added.
Scheme 4. Plausible Mechanism
these processes by reaction of allyl bromide with tin appears to
create a nonsufficiently acidic solution to promote hydration of
the nitroalkene (Table 1, entry 1). It is known that conversion
of a nitro into a carbonyl group requires an aqueous TiCl3
solution with a pH lower than 1.12 However, we observed that
addition of 20% TiCl3 in 3% hydrochloric acid to an aqueous
solution of the in situ generated allylstannane does not promote
formation of the aldehyde intermediate needed for the
allylation reaction. Instead, the process occurring under these
conditions results in the formation of a complicated mixture of
products (Table 1, entry 2). In addition, the product forming
reaction does not take place when allylstannane is generated in
situ using less reactive SnCl2 (Table 1, entry 3).
Taking into account the above findings, we envisioned that
phenylacetaldehyde would be highly labile under reaction
conditions in which TiCl3 is present.13 Therefore, a process,
utilizing hydrochloric acid as a promoter, was probed. Indeed, a
much cleaner reaction was found to take place (Table 1, entry 4
versus 2). Moreover, the efficiency of product formation in this
reaction was observed to be strongly effected by the order in
which the reagents are added (Table 1, entry 5 versus 4). The
process carried out by adding the nitroalkene to the acid
solution of the reagents gives a better yield than one in which
hydrochloric acid is added to the mixture. The results of
screening several strong acids (Table 1, entries 5−8) show that
the reaction proceeds in each case, albeit in low yields (Table 1,
entries 6−8), and that hydrochloric acid is the best promoter of
the reaction, affording the arylmethyl-homoallylic alcohol
reaction.16 The pathway involves initial generation of a
nitrostyrene radical anion 3 by single electron transfer from
tin followed by bis-protonation to produce the protonated
nitronic acid 4. Hydrolysis of 4 then occurs to generate the
aldehyde intermediate 5, which undergoes allylation to form
the homoallylic alcohol 2.
The scope of the newly developed allylation reaction was
explored utilizing a variety of aryl-nitroalkenes (Table 2). The
results show that this method can be used to prepare a wide
variety of arylmethyl-homoallylic alcohols containing an
assortment of ortho-, meta-, and para-positioned aryl ring
substituents such as hydroxyl, methoxyl, chloro, bromo, ethyl,
methyl, and cyano (Table 2, entries 2−13). It is worth noting
that all of the nitroalkene substrates are insoluble in water yet
the tin-mediated allylation reactions of these substances are
performed using fully aqueous solutions. As expected, some of
the low yields of the processes occurring in water can be
significantly improved by utilizing THF, acetonitrile, and
diethyl ether as cosolvents (Table 2, entries 8, 10, 12, and
14). A particularly significant finding, especially in light of the
1279
dx.doi.org/10.1021/jo302572s | J. Org. Chem. 2013, 78, 1278−1282

The Journal of Organic Chemistry
Note
TLC glass plate (Silica gel 60 F254) and were visualized using UV and
a solution of phosphomolybdic acid in ethanol (5 wt %) or p-
anisaldehyde stain. Flash chromatography was performed using silica
gel (70−230 mesh). 1H and 13C NMR spectra were recorded on a 300
MHz spectrometer. Chemical shifts are reported relative to CHCl3 [δH
7.24, δC (central line) 77.0]. Mass spectra were recorded under fast
atom bombardment (FAB), and high-resolution mass spectra were
recorded by electron impact ionization with a magnetic sector
analyzer.
Table 2. Tin-Mediated Allylation Reactions of Aryl-
nitroalkenes
a
General Procedure for Tin-Mediated Allylation Reactions of
Nitroalkenes. To a mixture of allyl bromide (2.0 mmol), tin powder
(2.0 mmol), and 37% aqueous hydrochloric acid (0.2 mL) in water
(1.8 mL), β-nitrostyrene (1.0 mmol) was added. The resulting mixture
was stirred at ambient temperature. The reaction was monitored by
TLC until no starting material was observed, and normally the reaction
was stirred at rt for 1.5 h. Et2O (5 mL) was then added to the reaction,
and the mixture was transferred to a separatory funnel. The organic
layer was back extracted with Et2O (5 mL). The combined organic
layers were washed with brine (3 mL × 2), dried over MgSO4, and
concentrated in a rotary evaporator. The residue was purified by silica-
gel chromatography using EtOAc/hexanes (1:25) as eluent to give the
product.
1-Phenylpent-4-en-2-ol (2a, Table 2, entry 1). 112 mg (69%).
1
An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.43; H NMR (300 MHz,
CDCl3) δ 1.76 (br s, 1 H), 2.15−2.37 (m, 2 H), 2.67−2.84 (m, 2 H),
3.82−3.91 (m, 1 H), 5.11−5.17 (m, 2 H), 5.78−5.92 (m, 1 H), 7.19−
7.32 (m, 5 H); 13C NMR (75 MHz, CDCl3) δ 41.1 (CH2), 43.2
(CH2), 71.6 (CH), 118.1 (CH2), 126.4 (CH), 128.4 (2 × CH), 129.3
(2 × CH), 134.6 (CH), 138.3 (C). These data are in agreement with
those reported in the literature.7
2-(2-Hydroxypent-4-enyl)phenol (2b, Table 2, entry 2). 130
1
mg (73%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.33; H NMR
(300 MHz, CDCl3) δ 2.16−2.21 (m, 1 H), 2.30−2.37 (m, 1 H), 2.73−
2.92 (m, 3 H), 3.97−4.01 (m, 1 H), 5.11−5.19 (m, 2 H), 5.76−5.81
(m, 1 H), 6.79−7.16 (m, 4 H), 8.21 (br s, 1 H); 13C NMR (75 MHz,
CDCl3) δ 38.5 (CH2), 41.2 (CH2), 72.6 (CH), 117.1 (CH), 119.0
(CH2), 120.3 (CH), 125.0 (C), 128.3 (CH), 131.5 (CH), 133.9 (CH),
155.3 (C). These data are in agreement with those reported in the
literature.7
1-(2-Methoxyphenyl)pent-4-en-2-ol (2c, Table 2, entry 3).
1
121 mg (63%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.43; H
NMR (300 MHz, CDCl3) δ 2.16 (s, 1 H), 2.19−2.30 (m, 2 H), 2.73
(dd, J = 13.5, 7.2 Hz, 1 H), 2.87 (dd, J = 13.5, 4.5 Hz, 1 H), 3.81 (s, 3
H), 3.85−3.95 (m, 1 H), 5.08−5.16 (m, 2 H), 5.80−5.92 (m, 1 H),
6.84−6.92 (m, 2 H), 7.12−7.23 (m, 2 H); 13C NMR (75 MHz,
CDCl3) δ 37.9 (CH2), 41.4 (CH2), 55.2 (CH3), 70.9 (CH), 110.4
(CH), 117.5 (CH2), 120.6 (CH), 126.9 (C), 127.8 (CH), 131.3 (CH),
135.1 (CH), 157.5 (C); EI-MS m/z (rel intensity) 192 (M+, 12), 151
(52), 122 (100), 91 (76). HRMS: [M]+ calcd for C12H16O2, 192.1150;
found, 192.1156.
a
Conditions: To a suspension of allyl bromide (2.0 mmol), tin powder
1-o-Tolylpent-4-en-2-ol (2d, Table 2, entry 4). 95 mg (54%).
An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.50; H NMR (300 MHz,
(2.0 mmol), and HCl (0.2 mL) in water (1.8 mL) at rt, nitroalkene
b
1
(1.0 mmol) was added. Conditions: THF (1 mL) and water (0.8 mL)
c
CDCl3) δ 1.70 (d, J = 2.1 Hz, 1 H), 2.22−2.39 (m, 5 H), 2.73 (dd, J =
13.8, 8.1 Hz, 1 H), 2.82 (dd, J = 13.8, 5.1 Hz, 1 H), 3.83−3.89 (m, 1
H), 5.12−5.19 (m, 2 H), 5.79−5.93 (m, 1 H), 7.11−7.17 (m, 4 H);
13C NMR (75 MHz, CDCl3) δ 19.6 (CH3), 40.4 (CH2), 41.4 (CH2),
70.7 (CH), 118.1 (CH2), 125.9 (CH), 126.6 (CH), 130.1 (CH), 130.4
(CH), 134.7 (CH), 136.6 (C), 136.7 (C); EI-MS m/z (rel intensity)
176 (M+, 5), 135 (33), 117 (20), 106 (100). HRMS: [M]+ calcd for
C12H16O, 176.1201; found, 176.1197.
were used as solvent. Conditions: CH3CN (1 mL) and water (0.8
d
mL) were used as solvent. Conditions: Et2O (1 mL) and water (0.8
mL) were used as solvent.
fact that the preparation of α-aryl methyl ketones is a
challenging synthetic problem,17 is that reaction of nitroalkene
1o generates a substance in this family (Table 2, entry 15).
In conclusion, the studies described above have led to the
development of a new, simple, inexpensive, and potentially
scalable method for the synthesis of arylmethyl-homoallylic
alcohols from nitroalkenes.
1-(2-Chlorophenyl)pent-4-en-2-ol (2e, Table 2, entry 5). 114
1
mg (58%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.45; H NMR
(300 MHz, CDCl3) δ 1.71 (d, J = 3.9 Hz, 1 H), 2.21−2.35 (m, 2 H),
2.80 (dd, J = 13.8, 8.1 Hz, 1 H), 2.99 (dd, J = 13.8, 4.8 Hz, 1 H), 3.90−
4.05 (m, 1 H), 5.12−5.19 (m, 2 H), 5.79−5.90 (m, 1 H), 7.14−7.36
(m, 4 H); 13C NMR (75 MHz, CDCl3) δ 40.8 (CH2), 41.4 (CH2),
70.0 (CH), 118.3 (CH2), 126.7 (CH), 127.9 (CH), 129.6 (CH), 131.7
(CH), 134.3 (C), 134.4 (CH), 136.3 (C); EI-MS m/z (rel intensity)
196 (M+, 3), 155 (62), 126 (90), 91 (100). HRMS: [M]+ calcd for
C11H13ClO, 196.0655; found, 196.0648.
EXPERIMENTAL SECTION
General Information and Materials. All commercially available
chemicals were used without further purification. β-nitrostyrenes18
were prepared from reported procedures. TLC analyses were run on a
■
1280
dx.doi.org/10.1021/jo302572s | J. Org. Chem. 2013, 78, 1278−1282

The Journal of Organic Chemistry
Note
1-(2-Bromophenyl)pent-4-en-2-ol (2f, Table 2, entry 6). 118
mg (49%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.45; H NMR
4-(2-Hydroxypent-4-enyl)benzonitrile (2m, Table 2, entry
13). 127 mg (68%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.20;
1H NMR (300 MHz, CDCl3) δ 1.78 (s, 1 H), 2.15−2.34 (m, 2 H),
1
(300 MHz, CDCl3) δ 1.71 (d, J = 3.6 Hz, 1 H), 2.31−2.36 (m, 2 H),
2.81 (dd, J = 13.8, 8.1 Hz, 1 H), 3.00 (d, J = 13.8, 4.8 Hz, 1 H), 3.90−
4.05 (m, 1 H), 5.12−5.19 (m, 2 H), 5.79−5.87 (m, 1 H), 7.04−7.10
(m, 1 H), 7.20−7.27 (m, 2 H), 7.53 (d, J = 7.8 Hz, 1 H); 13C NMR
(75 MHz, CDCl3) δ 41.4 (CH2), 43.2 (CH2), 70.0 (CH), 118.2
(CH2), 124.8 (C), 127.3 (CH), 128.1 (CH), 131.7 (CH), 132.8 (CH),
134.4 (CH), 138.0 (C); EI-MS m/z (rel intensity) 240 (M+, 5), 199
(34), 172 (58), 91 (100). HRMS: [M]+ calcd for C11H13BrO,
240.0150; found, 240.0155.
2.75 (dd, J = 13.8, 7.8 Hz, 1 H), 2.85 (dd, J = 13.8, 4.5 Hz, 1 H), 3.78−
3.92 (m, 1 H), 5.10−5.17 (m, 2 H), 5.74−5.85 (m, 1 H), 7.31 (d, J =
8.1 Hz, 2 H), 7.56 (d, J = 8.1 Hz, 2 H); 13C NMR (75 MHz, CDCl3) δ
41.4 (CH2), 43.0 (CH2), 70.9 (CH), 110.1 (C), 118.7 (CH2), 118.9
(C), 130.1 (2 × CH), 132.0 (2 × CH), 133.9 (CH), 144.4 (C); EI-MS
m/z (rel intensity) 187 (M+, 0.1), 146 (32), 118 (21), 117 (100).
HRMS: [M]+ calcd for C12H13NO, 187.0997; found, 187.0990.
1-(Naphthalen-2-yl)pent-4-en-2-ol (2n, Table 2, entry 14).
1
121 mg (57%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.35; H
1-(3-Bromophenyl)pent-4-en-2-ol (2g, Table 2, entry 7). 118
1
NMR (300 MHz, CDCl3) δ 1.87 (br s, 1 H), 2.24−2.37 (m, 2 H), 2.88
(dd, J = 13.8, 7.8 Hz, 1 H), 2.98 (dd, J = 13.8, 5.1 Hz, 1 H), 3.90−4.05
(m, 1 H), 5.14−5.21 (m, 2 H), 5.82−5.93 (m, 1 H), 7.36 (dd, J = 8.4,
1.5 Hz, 1 H), 7.42−7.50 (m, 2 H), 7.67 (s, 1 H), 7.78−7.84 (m, 3 H);
13C NMR (75 MHz, CDCl3) δ 41.1 (CH2), 43.3 (CH2), 71.5 (CH),
118.0 (CH2), 125.4 (CH), 126.0 (CH), 127.4 (CH), 127.5 (CH),
127.7 (CH), 127.8 (CH), 128.0 (CH), 132.2 (C), 133.4 (C), 134.6
(CH), 135.8 (C). These data are in agreement with those reported in
the literature.20
mg (49%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.38; H NMR
(300 MHz, CDCl3) δ 1.73 (d, J = 3.3 Hz, 1 H), 2.16−2.31 (m, 2 H),
2.66 (dd, J = 13.8, 7.8 Hz, 1 H), 2.76 (dd, J = 13.8, 4.8 Hz, 1 H), 3.75−
3.90 (m, 1 H), 5.10−5.17 (m, 2 H), 5.75−5.87 (m, 1 H), 7.13−7.18
(m, 2 H), 7.32−7.37 (m, 2 H); 13C NMR (75 MHz, CDCl3) δ 41.2
(CH2), 42.7 (CH2), 71.3 (CH), 118.4 (CH2), 122.4 (C), 128.0 (CH),
129.5 (CH), 129.9 (CH), 132.3 (CH), 134.2 (CH), 140.8 (C); EI-MS
m/z (rel intensity) 240 (M+, 7), 199 (28), 170 (63), 91 (100). HRMS:
[M]+ calcd for C11H13BrO, 240.0150; found, 240.0145.
2-Methyl-1-phenylpent-4-en-2-ol (2o, Table 2, entry 15). 85
mg (48%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.45; H NMR
1-(3,5-Dimethoxyphenyl)pent-4-en-2-ol (2h, Table 2, entry
8). 131 mg (59%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.25; 1H
NMR (300 MHz, CDCl3) δ 1.77 (br s, 1 H), 2.16−2.34 (m, 2 H), 2.62
(dd, J = 13.5, 8.1 Hz, 1 H), 2.73 (dd, J = 13.5, 4.8 Hz, 1 H), 3.75 (s, 6
H), 3.77−3.88 (m, 1 H), 5.10−5.17 (m, 2 H), 5.78−5.91 (m, 1 H),
6.31−6.36 (m, 3 H); 13C NMR (75 MHz, CDCl3) δ 41.1 (CH2), 43.5
(CH2), 55.2 (2 × CH3), 71.5 (CH), 98.4 (CH), 107.3 (CH), 118.0
(CH2), 134.6 (2 × CH), 140.6 (C), 160.8 (2 × C); EI-MS m/z (rel
intensity) 222 (M+, 9), 204 (15), 181 (17), 152 (100). HRMS: [M]+
calcd for C13H18O3, 222.1256; found, 222.1249.
1
(300 MHz, CDCl3) δ 1.13 (s, 3 H), 1.53 (s, 1 H), 2.23 (dd, J = 7.2, 0.9
Hz, 2 H), 2.72 (d, J = 13.5 Hz, 1 H), 2.78 (d, J = 13.5 Hz, 1 H), 5.08−
5.18 (m, 2 H), 5.84−5.98 (m, 1 H), 7.19−7.32 (m, 5 H); 13C NMR
(75 MHz, CDCl3) δ 26.5 (CH3), 46.2 (CH2), 47.8 (CH2), 72.0 (C),
118.7 (CH2), 126.4 (CH), 128.1 (CH2 × 2), 130.5 (CH2 × 2), 134.0
(CH), 137.3 (C); EI-MS m/z (rel intensity) 176 (M+, 5), 135 (33),
117 (20), 106 (100). These data are in agreement with those reported
in the literature.21
4-(2-Hydroxypent-4-enyl)phenol (2i, Table 2, entry 9). 107
mg (60%). Pale yellow solid, mp 61−62 °C; TLC (EtOAc/hexanes
ASSOCIATED CONTENT
1
■
(1:4)) Rf = 0.23; H NMR (300 MHz, CDCl3) δ 1.77 (br s, 1 H),
S
* Supporting Information
2.17−2.34 (m, 2 H), 2.62 (dd, J = 13.8, 8.1 Hz, 1 H), 2.74 (dd, J =
13.8, 4.8 Hz, 1 H), 3.78−3.88 (m, 1 H), 5.10−5.16 (m, 2 H), 5.50 (br
s, 1 H), 5.77−5.90 (m, 1 H), 6.73 (d, J = 9.3 Hz, 2 H), 7.04 (d, J = 9.3
Hz, 2 H); 13C NMR (75 MHz, CDCl3) 40.9 (CH2), 42.1 (CH2), 72.0
(CH), 115.4 (2 × CH), 118.2 (CH2), 129.8 (C), 130.4 (2 × CH),
134.5 (CH), 154.4 (C); EI-MS m/z (rel intensity) 178 (M+, 14), 137
(19), 108 (100), 91 (16). HRMS: [M]+ calcd for C11H14O2, 178.0994;
found, 178.0986.
Complete characterization data (1H and 13C NMR and mass
spectral data) for all compounds. This material is available free
of charge via the Internet at http://pubs.acs.org.
AUTHOR INFORMATION
Corresponding Author
*E-mail: mhlin@cc.ncue.edu.tw.
Notes
■
1-(4-Methoxyphenyl)pent-4-en-2-ol (2j, Table 2, enrty 10).
1
98 mg (51%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.45; H
NMR (300 MHz, CDCl3) δ 1.75 (d, J = 3.3 Hz, 1 H), 2.18−2.32 (m, 2
H), 2.63 (dd, J = 13.8, 7.8 Hz, 1 H), 2.74 (dd, J = 13.8, 5.1 Hz, 1 H),
3.77 (s, 3 H), 3.78−3.84 (m, 1 H), 5.10−5.16 (m, 1 H), 5.77−5.89
(m, 1 H), 6.83 (d, J = 8.4 Hz, 2 H), 7.13 (d, J = 8.4 Hz, 2 H); 13C
NMR (75 MHz, CDCl3) δ 41.0 (CH2), 42.3 (CH2), 55.2 (CH3), 71.7
(CH), 113.9 (2 × CH), 117.9 (CH2), 130.3 (C), 134.7 (2 × CH),
134.7 (CH), 158.2 (C). These data are in agreement with those
reported in the literature.7
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
Financial support from the National Science Council of the
Republic of China, Taiwan is gratefully acknowledged.
REFERENCES
■
1-(4-Ethylphenyl)pent-4-en-2-ol (2k, Table 2, entry 11). 99
1
(1) (a) Li, C. J. Chem. Rev. 2005, 105, 3095. (b) Lindstrom, U. M.
̈
mg (52%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.53; H NMR
Chem. Rev. 2002, 102, 2751. (c) Chan, T. H.; Issac, B. M. Pure Appl.
Chem. 1996, 68, 919. (d) Li, C. J. Tetrahedron 1996, 52, 5643. (e) Li,
C. J.; Chan, T. H. Organic Reactions in Aqueous Media; John Wiley &
Sons, Inc.: New York, 1997. (f) Paquette, L. A. In Green Chemistry:
Frontiers in Benign Chemical Synthesis and Processing; Anastas, P.,
Williamson, T., Eds.; Oxford University Press: New York, 1998.
(2) Li, C. J. Metal-Mediated C−C Bond Formations in Aqueous
Media. In Organic Reactions in Water Principles, Strategies and
(300 MHz, CDCl3) δ 1.22 (t, J = 7.5 Hz, 3 H), 1.70 (d, J = 3.3 Hz, 1
H), 2.18−2.35 (m, 2 H), 2.58−2.71 (m, 3 H), 2.79 (dd, J = 13.5, 5.1
Hz, 1 H), 3.84−3.88 (m, 1 H), 5.11−5.17 (m, 2 H), 5.81−5.90 (m, 1
H), 7.12−7.13 (m, 4 H); 13C NMR (75 MHz, CDCl3) δ 15.5 (CH3),
28.4 (CH2), 41.1 (CH2), 42.8 (CH2), 71.7 (CH), 117.9 (CH2), 128.0
(2 × CH), 129.3 (2 × CH), 134.7 (CH), 135.4 (C), 142.4 (C). These
data are in agreement with those reported in the literature.7
1-(4-Bromophenyl)pent-4-en-2-ol (2l, Table 2, entry 12). 121
1
Applications; Lindstrom, U. M., Ed.; Blackwell: Ames, IA, 2007.
mg (50%). An oil; TLC (EtOAc/hexanes (1:4)) Rf = 0.38; H NMR
̈
(3) (a) Shi, W.; Wang, J.-X. J. Chem. Res. 2008, 5, 270. (b) Zhang, J.-
M.; Zhang, Y.-M. Chin. J. Chem. 2002, 20, 296. (c) Bao, W.; Zheng, Y.;
Zhang, Y. J. Chem. Res. (S) 1999, 732.
(300 MHz, CDCl3) δ 1.85 (s, 1 H), 2.13−2.31 (m, 2 H), 2.63 (dd, J =
13.8, 7.8 Hz, 1 H), 2.85 (dd, J = 13.8, 5.1 Hz, 1 H), 3.78−3.83 (m, 1
H), 5.08−5.15 (m, 2 H), 5.77−5.80 (m, 1 H), 7.07 (d, J = 8.4 Hz, 2
H), 7.40 (d, J = 8.4 Hz, 2 H); 13C NMR (75 MHz, CDCl3) δ 41.1
(CH2), 42.4 (CH2), 71.3 (CH), 118.2 (CH2), 120.2 (C), 131.0 (2 ×
CH), 131.4 (2 × CH), 134.3 (CH), 137.4 (C). These data are in
agreement with those reported in the literature.19
(4) Ballini, R.; Petrini, M. Tetrahedron 2004, 60, 1017.
(5) (a) Bezbarua, M. S.; Bez, G.; Barua, N. C. Chem. Lett. 1999, 4,
325. (b) Sera, A.; Fukumoto, S.; Tamura, M.; Tekabatake, K.; Yamada,
H.; Itoh, K. Bull. Chem. Soc. Jpn. 1991, 64, 1787. (c) Aizpurua, J. M.;
1281
dx.doi.org/10.1021/jo302572s | J. Org. Chem. 2013, 78, 1278−1282

The Journal of Organic Chemistry
Note
Oiarbide, M.; Palomo, C. Tetrahedron Lett. 1987, 28, 5365. (d) Varma,
R. S.; Varma, M.; Kabalka, G. W. Tetrahedron Lett. 1985, 26, 3777.
(6) Solorio, D. M.; Jennings, M. P. J. Org. Chem. 2007, 72, 6621.
(7) Lin, M.-H.; Hung, S.-F.; Lin, L.-Z.; Tsai, W.-S.; Chuang, T.-H.
Org. Lett. 2011, 13, 332.
(8) (a) Jiang, N.; Hu, Q.; Reid, C. S.; Lu, Y.; Li, C.-J. Chem. Commun.
2003, 2318. (b) Yadav, J. S.; Reddy, B. V. S.; Satheesh, G. Tetrahedron
Lett. 2003, 44, 6501. (c) Roy, U. K.; Roy, S. Tetrahedron 2006, 62, 678.
(d) Nishimoto, Y.; Inamoto, Y.; Saito, T.; Yasuda, M.; Baba, A. Eur. J.
Org. Chem. 2010, 18, 3382.
(9) (a) Lin, M.-H.; Lin, L.-Z.; Chuang, T.-H. Synlett 2011, 13, 1871.
(b) Lin, M.-H.; Lin, L.-Z.; Chuang, T.-H.; Liu, H.-J. Tetrahedron 2012,
68, 2630.
(10) (a) Yadav, J. S.; Subba Reddy, B. V.; Srinivas, R.; Ramalingam,
T. Synlett 2000, 10, 1447. (b) Varma, R. S.; Varma, M.; Kabalka, G. W.
Synth. Commun. 1986, 16, 91. (c) Varma, R. S.; Varma, M.; Kabalka, G.
W. Tetrahedron Lett. 1985, 26, 6013.
(11) These attempted metal combinations are gallium, indium, zinc,
Ga/In, Fe/TiCl3, Mn/TiCl3, In/TiCl3, In/InCl3, and Cu/SnCl2.
(12) McMurry, J. E.; Melton, J. J. Org. Chem. 1973, 38, 4367.
(13) Sera, A.; Fukumoto, S.; Tamura, M.; Takabatake, K.; Yamada,
H.; Itoh, K. Bull. Chem. Soc. Jpn. 1991, 64, 1787.
(14) Hass, H. B.; Susie, A. G.; Heider, R. L. J. Org. Chem. 1950, 15, 8.
(15) The optimal amount of hydrochloric acid (0.2 mL) was
employed in the reaction with 69% yield. HCl (0.1 mL) with 24%
yield; HCl (0.17 mL) with 66% yield; HCl (0.25 mL) with 58% yield;
HCl (0.4 mL) with 45% yield.
(16) A similar mechanism was reported in nickel(0)-mediated
reduction of nitroolefins to carbonyl compounds in ref 5a.
(17) Molinaro, C.; Mowat, J.; Gosselin, F.; O’Shea, P. D.; Marcoux,
J.-F.; Angelaud, R.; Davies, I. W. J. Org. Chem. 2007, 72, 1856 and
references cited therein.
(18) Mampreian, D. M.; Hoveyda, A. H. Org. Lett. 2004, 6, 2829.
(19) Jiang, N.; Hu, Q.; Reid, C. S.; Lu, Y.; Li, C.-J. Chem. Commun.
2003, 18, 2318.
(20) Yadav, J. S.; Reddy, B. V. S.; Sathesh, G. Tetrahedron Lett. 2003,
44, 6501.
(21) Harpp, D. N.; Gingras, M. J. Am. Chem. Soc. 1988, 110, 7737.
1282
dx.doi.org/10.1021/jo302572s | J. Org. Chem. 2013, 78, 1278−1282