Allylic amination of internal alkynes with aromatic and aliphatic amines using polymer-supported triphenylphosphane-palladium complex as a heterogeneous and recyclable catalyst

Article abstract of DOI:10.1002/ejoc.201000463

A facile and novel protocol for the allylic amination of internal alkynes with amines by using a polymer-supported triphenylphosphane-palladium complex [PS-TPP-Pd] as a highly active heterogeneous reusable catalyst was developed. The catalyst exhibited remarkable activity and is re-usable over five consecutive cycles. The protocol was applicable for a variety of hindered and functionalized aromatic/ aliphatic amines and afforded the desired allylic products in good to excellent yield.

Full text of DOI:10.1002/ejoc.201000463

FULL PAPER
DOI: 10.1002/ejoc.201000463
Allylic Amination of Internal Alkynes with Aromatic and Aliphatic Amines
Using Polymer-Supported Triphenylphosphane–Palladium Complex as a
Heterogeneous and Recyclable Catalyst
Yogesh S. Wagh,[a] Pawan J. Tambade,[a] Dinesh N. Sawant,[a] and
Bhalchandra M. Bhanage*[a]
Keywords: Palladium / Alkynes / Amination / Supported catalysts / Allylic compounds
A facile and novel protocol for the allylic amination of in-
ternal alkynes with amines by using a polymer-supported tri-
usable over five consecutive cycles. The protocol was appli-
cable for a variety of hindered and functionalized aromatic/
aliphatic amines and afforded the desired allylic products in
good to excellent yield.
phenylphosphane–palladium complex [PS–TPP–Pd] as
a
highly active heterogeneous reusable catalyst was devel-
oped. The catalyst exhibited remarkable activity and is re-
Considering drawbacks of previously reported methods,
we employed polymer-supported triphenylphosphane–pal-
ladium complex [PS–TPP–Pd] as a heterogeneous and recy-
clable catalyst for the allylic amination of internal alkynes.
The polymer-supported Pd catalyst has been used earlier
for various chemical reactions.[7a–7g] However, to the best of
our knowledge, such a type of catalyst has not yet been
explored for the allylic amination reaction. The excellent
yields of desired allylic amines were obtained by using
10 mol-% of catalyst under optimized reaction conditions.
Introduction
The synthesis of allylamines is important due to their
wide applications as intermediates in organic synthesis,[1]
biological properties,[2] and their existence in several natural
products.[3] One of the trustworthy routes for the synthesis
of this class of compounds involves allylic substitution of
allylic alcohol derivatives such as acetates, carbonates, and
halides in the presence of Pd0 catalysts.[4,5] Yamamoto and
co-workers[6] have reported a new methodology for the syn-
thesis of allylamines through hydroamination of internal al-
kynes by using a homogeneous Pd0/carboxylic acid catalytic
system. As products of this reaction were obtained through
formal addition of pronucleophiles to alkynes, no waste was
produced after completion of the reaction; moreover, the
reaction proceeds without addition of any base. However,
the use of a homogeneous palladium complex for allylic
amination produces palladium-based waste products in the
reaction and lacks catalyst recyclability. The loss of palla-
dium catalyst, even at the ppm level, is not desirable due to
its high cost and environmental effects. The most probable
way to develop an atom economic process that can mini-
mize the loss of expensive palladium is to employ a hetero-
geneous catalyst for this transformation. Therefore, the se-
arch for a heterogeneous and reusable catalyst that could
efficiently catalyze the hydroamination of internal alkynes
is the subject of the present work.
Results and Discussion
To develop a suitable protocol for the allylic amination
reactions, initially the reaction of 1-phenyl-1-propyne (2)
with N-methylaniline (1) in the presence of PS–TPP–Pd was
chosen as a model reaction (Scheme 1), and the influence of
various reaction parameters such as catalyst concentration,
temperature, and time were studied (Table 1, Entries 1–10).
Scheme 1. Palladium-catalyzed allylation of N-methylaniline with
1-phenyl-1-propyne.
[a] Department of Chemistry, Institute of Chemical Technology
(Autonomous),
In the case of transition-metal-catalyzed reactions, the
amount of catalyst employed proves to be an important fea-
ture, and considering such, efforts were made to determine
the optimum concentration of the catalyst (Table 1, En-
tries 1–3). Various catalyst loadings were used ranging from
N. Parekh Marg, Matunga, Mumbai 400019, India
Fax: +91-2224145614
E-mail: bhalchandra_bhanage@yahoo.com
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejoc.201000463.
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Y. S. Wagh, P. J. Tambade, D. N. Sawant, B. M. Bhanage
FULL PAPER
Table 1. Effect of reaction parameters on the allylic amination of lent yields of the products. Among all the solvents screened,
1-phenyl-1-propyne with N-methylaniline.[a]
toluene was found to provide an excellent yield of the prod-
uct (94%; Table 2, Entry 6).
Entry
Catalyst conc. [mol-%] Temp. [°C] Time [h] Yield [%][b]
Table 2. Effect of solvent on the allylic amination of 1-phenyl-1-
Effect of catalyst concentration
propyne with N-methylaniline.[a]
1
2
3
0.05
0.10
0.15
110
110
110
5
5
5
85
94
94
Entry
Solvent
Temp. [°C]
Yield [%][b]
1
2
3
4
5
6
7
acetonitrile
1,4-dioxane
DMF
cyclohexane
hexane
toluene
xylene
82
100
140
80
70
110
140
06
52
05
–
10
94
70
Effect of temperature
4
5
6
7
0.10
0.10
0.10
0.10
90
5
5
5
5
82
90
94
94
100
110
120
[a] Reaction conditions: Pd(OAc)2 (10 mol-%), PS–TPP (40 mol-
%), 1-phenyl-1-propyne (1 mmol), N-methylaniline (1 mmol),
PhCOOH (10 mol-%), 5 h. [b] GC yield.
Effect of time
8
9
0.10
0.10
0.10
0.10
110
110
110
110
4
5
6
5
84
94
94
61
10
During optimization of the reaction parameters, we ob-
served that if the ratio palladium/PS–TPP (Pd/P) employed
is 1:1, a 52% yield of the product was observed, but the
complex turns black after completion of the reaction, which
reveals that Pd is reduced to Pd0. The conversion of Pd to
metallic Pd0 may be due to an unstable palladium complex
formed due to the unavailability of a ligand. We tested the
same catalyst for its reuse but it was completely ineffective,
providing no yield of the desired product. We then carried
out allylic amination of 1-phenyl-1-propyne with N-methyl-
aniline by using Pd/C (which is also Pd0) as a catalyst, but
nor product was formed. From these results we conclude
that phosphane is essential for this reaction, as Pd0 in the
metallic state is completely ineffective.
The catalytic activity at different Pd/P ratios was studied
for the allylic amination of 1-phenyl-1-propyne with N-
methylaniline by using the optimized reaction conditions.
Pd/P ratios of 1:1, 1:2, 1:3, 1:4, and 1:5 were evaluated, and
it was observed that the yield of the product increases with
a smaller Pd/P ratio. During the reaction with Pd/P ratios
of 1:1, 1:2, and 1:3, the yield of the product was found to
be 52–75%; however, the color of the catalyst was found
to change from yellow to black (Table 3, Entries 1–3). The
complete conversion of the starting material was observed
for a Pd/P ratio of 1:4, providing 94% yield of the desired
product; the catalyst was isolated quantitatively after the
reaction as a yellowish solid. With a further decrease in the
ratio of Pd/P to 1:5, almost similar results were obtained.
A Pd/P ratio of 1:4 was used as the optimum henceforth.
11[c]
[a] Reaction conditions: PS–TPP [4 equiv. to Pd(OAc)2], 1-phenyl-
1-propyne (1 mmol), N-methylaniline (1 mmol), PhCOOH (10 mol-
%), toluene (4 mL). [b] GC yield. [c] Without benzoic acid.
5 to 15 mol-%. Initially, the reaction was carried out by
using 5 mol-% of the catalyst, which provided desired prod-
uct 3 in 85% yield. An increase in the catalyst concentration
to 10 mol-% resulted in an increase in the yield of 3 up to
94% (Table 1, Entry 2). Further increase in the amount of
catalyst had no profound effect on the yield of the desired
product (Table 1, Entry 3).
Also, the reaction was carried out at different tempera-
tures ranging from 90 to 120 °C (Table 1, Entries 4–7). It
was observed that at 90 °C, the yield of the product was
very low, and with an increase in the temperature to 110 °C,
the yield of 3 increased to 94%. However, a further increase
in temperature did not show any significant enhancement
in the yield (Table 1, Entry 7). The influence of time on the
reaction outcome was also studied (Table 1, Entries 8–10),
reflecting 5 h to be sufficient under the present reaction
conditions (Table 1, Entry 9). We also checked the role of
benzoic acid in our catalytic system. In the presence of ben-
zoic acid, the yield of the desired product was optimum,
that is, 94%; however, in the absence of benzoic acid, the
yield obtained was low (Table 1, Entry 11). We think that
the presence of benzoic acid plays the role of cocatalyst,
which is to be in agreement with the observation made by
Yamamoto and co-workers.[6d]
The effect of various polar and nonpolar solvents on al-
lylic amination was studied to find out the optimum solvent
for the reaction (Table 2, Entries 1–7). Polar solvents such
as acetonitrile and DMF provided lower yields of the prod-
ucts (Table 2, Entries 1 and 3). However, 1,4-dioxane of-
fered a moderate yield of the product (Table 2, Entry 2).
Nonpolar solvents like toluene, xylene, cyclohexane, and
hexane were screened, and it was observed that the reaction
did not proceed in the case of low-boiling solvents such as
cyclohexane. In the case of n-hexane, the reaction gave only
10% yield of the desired product. High-boiling nonpolar
Table 3. Effect of Pd/PS–TPP (Pd/P) ratio on the allylic amination
of 1-phenyl-1-propyne with N-methylaniline.[a]
Entry
Pd/P
ratio
Pd(OAc)2 PS–TPP
Color of
catalyst
Yield
[%][b]
[mol-%]
[mol-%]
1
2
3
4
5
1:1
1:2
1:3
1:4
1:5
10
10
10
10
10
10
20
30
40
50
black
black
brown-black
yellow
52
70
75
94
94
yellow
[a] Reaction conditions: 1-phenyl-1-propyne (1 mmol), N-methyl-
aniline (1 mmol), PhCOOH (10 mol-%), toluene (4 mL). [b] GC
solvents such as toluene and xylene produced good to excel- yield.
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Allylic Amination of Internal Alkynes with Aromatic and Aliphatic Amines
Table 4. Allylic amination of 1-phenylpropyne with various amines.[a]
[a] Amine (1) (1 mmol), 1-phenyl-1-propyne (2) (1 mmol), Pd(OAc)2 (10 mol-%), PS–TPP (40 mol-%), PhCOOH (10 mol-%), toluene
(4 mL) at 110 °C. [b] Isolated yields.
Eur. J. Org. Chem. 2010, 5071–5076
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Y. S. Wagh, P. J. Tambade, D. N. Sawant, B. M. Bhanage
FULL PAPER
Thus, the optimized reaction conditions are: Pd(OAc)2 clined to 85% at the end of the fifth consecutive cycle and
(10 mol-%), PS–TPP (40 mol-%), toluene (4 mL) at 110 °C the color of the catalyst turned black-brown after comple-
for 5 h.
tion of the fifth cycle, which was yellow up this cycle
The optimized reaction conditions were used in the al- (Table 5).
lylic amination of 1-phenylpropyne (2) with different aro-
matic and aliphatic amines, and the desired products were
Table 5. Reusability of the catalyst.[a]
obtained in moderate to excellent yields (Table 4, Entries 1– Entry
16). The reaction of 2 with N-phenylaniline provided a
Pd/P
ratio
PS–TPP
[mol-%]
Recycle no. (% yield[b])
1
2
3
4
5
moderate yield of the desired product (Table 4, Entry 2).
The reaction of aniline with 2 gave an excellent yield of the
product with 90:10 ratio (mono-/diallylated; Table 4, En-
try 3). The effect of various activating groups such as Me,
OMe, F, and Cl at the ortho position of aniline were well
tolerated to give selectively the monoallylic product in ex-
cellent yields (Table 4, Entries 4–7). The reaction of 2 with
o-trifluoromethylaniline and o-nitroaniline furnished the
monoallylated products in excellent yields (Table 4, En-
tries 8 and 9). The reaction of 2 with disubstituted 2,4-di-
fluoroaniline provided the desired monoallylated product in
excellent yield (Table 4, Entry 10). Compound 2 reacted
smoothly with m-trifluoromethylaniline, providing a mix-
ture of mono- and diallylated product in a ratio of 90:10
(Table 4, Entry 11). p-Anisidine also reacted efficiently with
2, providing a mixture of mono- and diallylated product
in a ratio of 85:15 (Table 4, Entry 12). The reaction of p-
nitroaniline with 2 proceeded smoothly, providing 82% of
product with a 80:20 ratio of mono-/diallylated products
(Table 4, Entry 13).
To explore the generality and applicability of the proto-
col, we turned our attention towards the allylation of ali-
cyclic amines such as morpholine as well as secondary ali-
phatic amines such as dibutylamine and diisopropylamine
with 2 (Table 4, Entries 14–16). The reaction with morph-
oline gave 90% yield of 4-(3-phenylallyl)morpholine under
the optimized reaction conditions, whereas dibutylamine
and diisopropylamine were found to be less reactive, provid-
ing the product in moderate to good yields (Table 4, En-
tries 15 and 16). Thus, the developed protocol proved to be
general for the allylic amination of 1-phenyl-1-propyne (2)
with various structurally and electronically different aro-
matic and aliphatic amines, providing good to excellent
yields of the desired product.
1
2
3
4
5
1:1
1:2
1:3
1:4
1:5
10
20
30
40
50
–
–
–
–
88
88
–
–
–
85
88
–
–
–
85
85
–
–
–
85
85
36
38
90
92
[a] Reaction conditions: Pd(OAc)2 (10 mol-%), 1-phenyl-1-propyne
(1 mmol), N-methylaniline (1 mmol), PhCOOH (10 mol-%), tolu-
ene (4 mL), 110 °C, 5 h. [b] GC yield.
Maintaining the color of the catalyst after reaction indi-
rectly indicates that palladium is complexed to phosphane.
In the case of a Pd/P ratio of 1:5 similar results were ob-
tained. To check whether the palladium leached during the
reaction, we carried out ICP-AES analysis of the reaction
mixture after completion of the reaction. The result of ICP-
AES analysis revealed that there was no leaching of palla-
dium.
Conclusions
In conclusion, we have developed an efficient protocol
for the allylation of aromatic and aliphatic amines by using
a [PS–TPP–Pd] complex as a heterogeneous and recyclable
catalyst. The reaction was optimized with respect to various
reaction parameters and enabled allylation reactions of
various electron-rich, electron-deficient, and sterically hin-
dered aromatic and aliphatic amines, affording excellent
yields of the desired products, thus illustrating the broad
applicability of the methodology. Further, the [PS–TPP–Pd]
complex was recycled for five consecutive cycles without
any significant loss in catalytic activity.
Experimental Section
To check whether the catalyst was active to catalyze the
reaction in more catalytic cycles and to make the protocol
economically viable we attempted to recycle the catalyst.
Recyclability experiments at different Pd/P ratios were
studied for the allylic amination of 1-phenyl-1-propyne with
N-methylaniline by using standard reaction conditions. A
Pd/P ratio of 1:1 did not give any product during the recy-
cling experiment, and the starting material was recovered
quantitatively. Pd/P ratios of 1:2 and 1:3 showed lower
yields of the products during the first recycling run. How-
ever, Pd/P ratios of 1:4 and 1:5 both gave excellent yields of
the desired products during the first recycling run, and
hence we checked the recyclability in both cases for further
consecutive cycles. It was observed that in case of a Pd/P
ratio of 1:4 there was no significant decrease in the yield of
Materials and Methods: Palladium acetate, polymer-supported tri-
phenylphosphane (loading ca. 3 mmol/g), 1-phenyl-1-propyne,
amines, and benzoic acid were purchased from Sigma–Aldrich Ltd.
in their highest purity available and were used as is. Optimized
yields were based on GC (Chemito 1000) and GC–MS (Shimadzu
QP 2010) analysis. All the products are known, and representative
products were characterized by 1H NMR (Varian 300 MHz or Var-
ian 400 MHz) and 13C NMR (Varian 75 MHz) spectroscopy and
GC–MS (Shimadzu QP 2010) analysis. Purity of all the compounds
were determined by GC–MS analysis.
General Procedure for the Allylation of Amines: In a typical experi-
ment, a 25-mL round-bottomed flask was charged with Pd(OAc)2
(22.4 mg, 10 mol-%), polymer-supported triphenylphosphane (PS–
TPP; 133 mg, 40 mol-%), and toluene (4 mL), and the mixture was
stirred for 20 min at 110 °C.[7c] The reaction mixture was cooled to
room temperature followed by the addition of 1-phenyl-1-propyne
the product in the second recycling, whereas the yield de- (116 mg, 1 mmol), amine (1 mmol), and benzoic acid (12 mg,
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Allylic Amination of Internal Alkynes with Aromatic and Aliphatic Amines
10 mol-%). The resulting mixture was stirred for 5 h at 110 °C and
then cooled to room temperature. The catalyst was separated by
filtration, washed with an excess amount of toluene and dried un-
der vacuum. The filtrate obtained was removed under reduced pres-
sure, and the product was purified by column chromatography (sil-
ica gel, 60–120 mesh; petroleum ether/ethyl acetate, 95:05) to afford
the desired products. All the prepared compounds were confirmed
7.45 (m, 7 H, 7 CH, Ar), 6.61–6.79 (m, 2 H, 2 CH, Ar), 6.63 (d, J
= 16 Hz, 1 H, CH=CHAr), 6.31 (td, J = 16, 5.6 Hz, 1 H,
CH2CH=CH), 4.59 (br. s, 1 H, NH), 4.02 (d, J = 4.8 Hz, 2 H,
HNCH2CH) ppm. 13C NMR (75 MHz, CDCl3, 25 °C): δ = 145.74
(N-Cq, Ar), 136.67 (Cq, Ar), 133.17 (CH, Ar), 131.94
(CH2CH=CH), 128.65 (2 CH, Ar), 127.75 (CH, Ar), 127.15 (CH,
Ar), 126.67 (CF3), 126.46 (2 CH, Ar), 125.94 (CH=CHAr), 116.21
(CH, Ar), 113.56 (Cq, Ar), 112.24 (CH, Ar), 45.63 (NCH2CH)
ppm. GC–MS (EI, 70 eV): m/z (%) = 277 (29) [M]+, 117 (100), 115
(38), 91 (19), 77 (5.5).
1
by GC–MS and H and 13C NMR spectroscopy.
N-Cinnamyl-N-methylaniline: Liquid. Yield: 209 mg, 94% (Table 4,
1
Entry 1). H NMR (300 MHz, CDCl3, 25 °C): δ = 7.16–7.34 (m, 7
N-Cinnamyl-2-nitroaniline: Solid. Yield: 223 mg, 88% (Table 4, En-
try 9). MS–MS (ESI–): m/z = 253.13 [M – 1]–.
H, 7 CH, Ar), 6.76 (d, J = 7.69 Hz, 2 H, 2 CH, Ar), 6.71 (t, J =
7.33 Hz, 1 H, CH, Ar), 6.49 (d, J = 16.13 Hz, 1 H, CH=CHAr),
6.21 (td, J = 16.13, 5.49 Hz, 1 H, CH2CH=CH), 4.03 (dd, J = 5.49,
1.46 Hz, 2 H, NCH2CH), 2.94 (s, 3 H, NCH3) ppm. 13C NMR
(75 MHz, CDCl3, 25 °C): δ = 149.75 (N-Cq, Ar), 137.08 (Cq, Ar),
131.44 (CH2CH=CH), 129.37 (2 CH, Ar), 128.70 (2 CH, Ar),
127.57 (CH, Ar), 126.50 (2 CH, Ar), 125.93 (CH=CHAr), 116.78
(CH, Ar), 112.81 (2 CH, Ar), 55.05 (NCH2CH), 38.17 (NCH3)
ppm. GC–MS (EI, 70 eV): m/z (%) = 223 (40) [M]+, 118 (12), 117
(100), 115 (45), 91 (25), 51 (8.9), 44 (15.2).
N-Cinnamyl-2,4-difluoroaniline: Solid. Yield: 244 mg, 98% (Table 4,
1
Entry 10). H NMR (400 MHz, CDCl3, 25 °C): δ = 7.22–7.38 (m,
7 H, 7 CH, Ar), 6.66–6.83 (m, 2 H, 2 CH, Ar), 6.63 (d, J = 16 Hz,
1 H, CH=CHAr), 6.26 (d, J = 16 Hz, 1 H, CH2CH=CH), 3.95 (d,
J = 3.7 Hz, 2 H, HNCH2CH) ppm. 13C NMR (75 MHz, CDCl3,
25 °C): δ = 154.51 (F-Cq, Ar), 150.58 (F-Cq, Ar), 136.77 (Cq, Ar),
133.07 (N-Cq, Ar), 131.92 (CH2CH=CH), 128.73 (2 CH, Ar),
127.80 (CH, Ar), 126.49 (3 CH, CH=CHAr, Ar), 112.42 (CH, Ar),
110.74 (CH, Ar), 103.53 (CH, Ar), 46.27 (NCH2CH) ppm. GC–
MS (EI, 70 eV): m/z (%) = 245(24) [M]+, 117 (100), 115 (43), 91
(19).
N-Cinnamyl-N-phenylaniline: Solid. Yield: 213 mg, 75% (Table 4,
Entry 2). GC–MS (EI, 70 eV): m/z (%) = 285 (20) [M]+, 167 (12.7),
118 (10), 117 (100), 115 (30), 91 (16.5), 77 (12), 44 (15.7).
N-Cinnamyl-3-(trifluoromethyl)aniline: Liquid. Yield: 206 mg, 74%
(Table 4, Entry 11). H NMR (300 MHz, CDCl3, 25 °C): δ = 7.2–
N-Cinnamylaniline: Liquid. Yield: 170 mg, 82% (Table 4, Entry 3).
GC–MS (EI, 70 eV): m/z (%) = 209(39) [M+], 117 (100), 115 (45),
91 (24), 77 (20), 44 (21).
1
7.38 (m, 6 H, 6 CH, Ar), 6.94 (d, J = 7.3 Hz, 1 H, 1 CH, Ar), 6.84
(s, 1 H, Ar), 6.76 (d, J = 8 Hz, 1 H, CH, Ar), 6.62 (d, J = 15.76 Hz,
1 H, CH=CHAr), 6.27 (td, J = 15.76, 5.5 Hz, 1 H, CH2CH=CH),
4.01 (br. s, 1 H, NH), 3.39 (d, J = 4.8 Hz, 2 H, HNCH2CH) ppm.
13C NMR (75 MHz, CDCl3, 25 °C): δ = 148.21 (N-Cq, Ar), 136.7
(Cq, Ar), 132.1 (2 C, CH2CH=CH, Cq-CF3), 129.72 (CH, Ar),
128.69 (2 CH, Ar), 127.77 (CH, Ar), 126.43 (2 CH, Ar), 126.11
(CH=CHAr), 115.96 (CH, Ar), 114.0 (CH, Ar), 109.25 (CH, Ar),
45.97 (NCH2CH) ppm. GC–MS (EI, 70 eV): m/z (%) = 277 (29)
[M]+, 117 (100), 115 (38), 91 (19), 77 (6).
N,N-Dicinnamylaniline: Liquid. Yield: 35 mg, 11% (Table 4, En-
try 3). MS–MS (ESI+): m/z = 326.07 [M + 1]+.
N-Cinnamyl-2-methylaniline: Liquid. Yield: 209 mg, 94% (Table 4,
Entry 4). GC–MS (EI, 70 eV): m/z (%) = 223 (33.7) [M]+, 117 (100),
115 (38), 91 (29), 77 (9), 44 (14).
N-Cinnamyl-2-methoxyaniline: Liquid. Yield: 215 mg, 90%
1
(Table 4, Entry 5). H NMR (400 MHz, CDCl3, 25 °C): δ = 7.22–
7.39 (m, 5 H, 5 CH, Ar), 6.6–6.89 [m, 5 H, (4 CH, Ar, CH=CHAr)],
6.35 (td, J = 15.76, 5.86 Hz, 1 H, CH2CH=CH), 4.42 (br. s, 1 H, N,N-Dicinnamyl-3-(trifluoromethyl)aniline: Liquid. Yield: 32 mg,
NH), 3.95 (dd, J = 5.5, 1.46 Hz, 2 H, HNCH2CH), 3.85 (s, 3 H, 8.3% (Table 4, Entry 11). 1H NMR (300 MHz, CDCl3, 25 °C): δ =
OCH3) ppm. 13C NMR (75 MHz, CDCl3, 25 °C): δ = 146.92 (Cq,
Ar), 138.02 (N-Cq, Ar), 136.99 (Cq, Ar), 131.35 (CH2CH=CH),
128.56 (2 CH, Ar), 127.46 (CH, Ar), 127.27 (CH=CHAr), 126.36
(2 CH, Ar), 121.34 (CH, Ar), 116.71 (CH, Ar), 110.24 (CH, Ar),
109.45 (CH, Ar), 55.41 (OCH3), 45.94 (HNCH2CH) ppm. GC–MS
(EI, 70 eV): m/z (%) = 239 (43) [M]+, 117 (100), 115 (41), 91 (31),
77 (10), 45 (46), 44 (38).
7.21–7.55 (m, 11 H, 11 CH, Ar), 7.00 (s, 1 H, CH, Ar), 6.92–6.98
(m, 2 H, Ar), 6.54 (d, J = 16.12 Hz, 2 H, CH=CHAr), 6.24 (td, J
= 16.12, 5.5 Hz, 2 H, CH2CH=CH), 4.17 (d, J = 4.40 Hz, 4 H,
HNCH2CH) ppm. 13C NMR (75 MHz, CDCl3, 25 °C): δ = 148.02
(N-Cq, Ar), 136.73 (2 Cq, Ar), 131.81 (2 CH2CH=CH), 129.74
(Cq-CF3), 128.67 (4 CH, Ar), 127.70 (2 CH, Ar), 126.45 (4 CH,
Ar), 124.93 (CH, Ar), 115.53 (CH, Ar), 113.07 (CH, Ar), 108.80
(CH, Ar), 52.31 (HNCH2CH) ppm. MS–MS (ESI+): m/z = 394.33
[M + 1]+.
N-Cinnamyl-2-fluoroaniline: Liquid. Yield: 220 mg, 97% (Table 4,
1
Entry 6). H NMR (400 MHz, CDCl3, 25 °C): δ = 7.18–7.36 (m, 5
N-Cinnamyl-4-methoxyaniline: Solid. Yield: 172 mg, 72% (Table 4,
Entry 12). MS–MS (ESI+): m/z = 240.139 [M + 1]+.
H, 5 CH, Ar), 6.94–7.0 (m, 2 H, 2 CH, Ar), 6.73 (t, J = 8.8 Hz, 1
H, CH, Ar), 6.63 (m, 1 H, CH, Ar), 6.6 (d, J = 15.76 Hz, 1 H,
CH=CHAr), 6.28 (td, J = 15.76, 5.5 Hz, 1 H, CH2CH=CH), 4.1
(br. s, 1 H, NH), 3.93 (d, J = 5.5 Hz, 2 H, HNCH2CH) ppm. 13C
NMR (75 MHz, CDCl3, 25 °C): δ = 151.93 (F-Cq, Ar), 136.77 (Cq,
Ar), 136.6 (N-Cq, Ar), 131.70 (CH2CH=CH), 128.61 (2 CH, Ar),
127.64 (CH, Ar), 126.56 (CH=CHAr), 126.40 (2 CH, Ar), 124.64
(CH, Ar), 116.84 (CH, Ar), 114.45 (CH, Ar), 112.44 (CH, Ar),
45.74 (HNCH2CH) ppm. GC–MS (EI, 70 eV): m/z (%) = 227 (33.7)
[M]+, 117 (100), 115 (44), 91 (20), 77 (10).
N,N-Dicinnamyl-4-methoxyaniline: Solid. Yield: 42 mg, 12%
(Table 4, Entry 12). MS–MS (ESI+): m/z = 356.05 [M + 1]+.
N-Cinnamyl-4-nitroaniline: Solid, Yield: 166 mg, 65% (Table 4, En-
try 13). MS–MS (ESI–): m/z = 253.20 [M + 1]–.
N,N-Dicinnamyl-4-nitroaniline: Solid, Yield: 60 mg, 16% (Table 4,
Entry 13). MS–MS (ESI–): m/z = 369.27 [M + 1]–.
4-Cinnamylmorpholine: Liquid. Yield: 182 mg, 90% (Table 4, En-
try 14). MS (EI, 70 eV): m/z (%) = 203(32) [M]+, 144 (15), 117 (71),
115 (50), 112 (100), 91 (28), 56 (34).
N-Cinnamyl-2-chloroaniline: Liquid. Yield: 218 mg, 90% (Table 4,
Entry 7). GC–MS (EI, 70 eV): m/z (%) = 245 (7.2), 243 (21.7)
[M]+, 117 (100), 115 (40), 91 (19), 45 (39), 44 (32).
N-Butyl-N-cinnamylbutan-1-amine: Liquid. Yield: 183 mg, 75%
(Table 4, Entry 14). MS (EI, 70 eV): m/z (%) = 245 (3.5) [M]+, 202
(20.9), 117 (100), 115 (16).
N-Cinnamyl-2-(trifluoromethyl)aniline: Liquid. Yield: 218 mg, 98%
1
(Table 4, Entry 8). H NMR (400 MHz, CDCl3, 25 °C): δ = 7.23–
Eur. J. Org. Chem. 2010, 5071–5076
© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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5075

Y. S. Wagh, P. J. Tambade, D. N. Sawant, B. M. Bhanage
FULL PAPER
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N,N-Diisopropyl-3-phenylprop-2-en-1-amine: Liquid. Yield: 130 mg,
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202 (19), 117 (100), 115 (19), 91 (11), 44.
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Supporting Information (see footnote on the first page of this arti-
cle): Copies of the 1H and 13C NMR spectra of the prepared com-
pounds.
Acknowledgments
Financial assistance from the University Grants Commission, In-
dia for a major research project [Project No. 32–273/2006 (SR)] is
acknowledged.
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Received: April 6, 2010
Published Online: July 23, 2010
5076
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© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Org. Chem. 2010, 5071–5076