Mizoroki–Heck cross-coupling reactions using palladium immobilized on DABCO-functionalized silica

Article abstract of DOI:10.1007/s11243-019-00308-4

A heterogeneous palladium catalyst supported on silica modified by DABCO has been prepared by post-synthetic modification of silica gel. This heterogeneous catalytic system exhibits high activity and stability in the Mizoroki–Heck cross-coupling reaction of various aryl halides with olefins. The reaction proceeds efficiently under efficiently under mild mild reaction conditions and high yield, with the formation of E-isomers selectively. Moreover, we successfully established a gram-scale synthesis, and the catalyst was reused for up to ten catalytic cycles.

Full text of DOI:10.1007/s11243-019-00308-4

Transition Metal Chemistry
https://doi.org/10.1007/s11243-019-00308-4
Mizoroki–Heck cross‑coupling reactions using palladium immobilized
on DABCO‑functionalized silica
1
2
2
3
1
Sanjay Jadhav · Seema Patil · Arjun Kumbhar · Santosh Kamble · Rajashri Salunkhe
Received: 7 December 2018 / Accepted: 29 January 2019
©
Springer Nature Switzerland AG 2019
Abstract
A heterogeneous palladium catalyst supported on silica modifed by DABCO has been prepared by post-synthetic modifca-
tion oꢀ silica gel. This heterogeneous catalytic system exhibits high activity and stability in the Mizoroki–Heck cross-coupling
reaction oꢀ various aryl halides with olefns. The reaction proceeds eꢁciently under eꢁciently under mild mild reaction
conditions and high yield, with the ꢀormation oꢀ E-isomers selectively. Moreover, we successꢀully established a gram-scale
synthesis, and the catalyst was reused ꢀor up to ten catalytic cycles.
Introduction
biopolymers and zeolites [24]. Recently, it has been ꢀound
that Pd complexes with various ligands supported on silica
have considerable utility in various cross-coupling reactions
including Mizoroki–Heck cross-coupling reaction [25, 26],
as silica displays many advantageous properties such as
excellent chemical and thermal stability, good accessibility
and porosity. In addition, the organic groups can be easily
graꢀted on the silica surꢀace by simple post-synthetic modi-
fcations [27].
An important part oꢀ modern chemistry is based on the use
oꢀ precious platinum group metal (PGM) catalysts [1–9]. In
particular, Pd, which is an active metal with high demand,
has been most widely used ꢀor the ꢀabrication oꢀ carbon–car-
bon and carbon–heteroatom bonds ꢀor the production oꢀ
intermediates oꢀ biologically active compounds, natural
products and fne chemicals [10–13]. The Pd-catalyzed cou-
pling oꢀ olefns with aryl or vinyl halides [14] to ꢀorm a C–C
bond is known as the Mizoroki–Heck cross-coupling reac-
tion and has been widely used ꢀor the synthesis oꢀ important
compounds like ꢂavoring agents, pharmaceuticals, agro-
chemicals and UV absorbents [15, 16].
As amines are less toxic, inexpensive, easy to handle and
less air sensitive, catalytic systems based on DABCO might
be ideal to carry out the Mizoroki–Heck cross-coupling reac-
tion under phosphine-ꢀree conditions [28–31]. DABCO is a
cage-like, small diazabicyclic molecule with medium steric
hindrance and has received considerable attention as an
organocatalyst ꢀor various organic transꢀormations [32–35].
In 2014, Li et al. [36] reported the frst use oꢀ DABCO as a
ligand in Pd-catalyzed phosphine-ꢀree cross-coupling reac-
tions, while our research group reported [37] Pd–DABCO
Though the Mizoroki–Heck cross-coupling reaction
has been most widely applied with homogeneous catalysts
[
17–20], it suꢃers ꢀrom various disadvantages such as tedi-
ous workup procedures, lack oꢀ reusability and contamina-
tion oꢀ residual metals in the desired product. These disad-
vantages can be overcome by using heterogeneous catalysts,
via immobilization oꢀ Pd on various solid supports such as
polymers [21], activated carbons [22], metal oxides [23],
supported on SiO as an eꢃective reusable catalyst system
2
ꢀor Suzuki–Miyaura cross-coupling in aqueous ethanol using
K CO as a base at 80 °C. The results showed that the cata-
2
3
lyst could be used to convert a variety oꢀ aryl bromides and
boronic acids to the desired coupling products in good-to-
excellent yields, which encouraged us to use this catalytic
system ꢀor Mizoroki–Heck cross-coupling reactions. As a
matter oꢀ ꢀact, we succeeded in obtaining a very rapid and
quantitative conversion oꢀ various aryl bromides with diꢀ-
*
Rajashri Salunkhe
rss234@rediꢃmail.com
1
2
3
Department oꢀ Chemistry, Shivaji University, Kolhapur,
M.S. 416004, India
Department oꢀ Chemistry, P.D.V.P. College, Tasgaon,
M.S. 416312, India
ꢀ
erent olefns into a variety oꢀ coupling products in DMF
using K CO as a base at 100 °C temperature and with high
2
3
Department oꢀ Chemistry, Yashvantrao Chavan Institute
oꢀ Science, Satara, M.S. 415001, India
selectivity.
Vol.:(0
1
123456789)
3

Transition Metal Chemistry
Scheme 1 Preparation oꢀ Pd–DABCO@SiO catalyst
2
Table 1 Optimization studies ꢀor Mizoroki–Heck coupling reactiona
Entry
Solvent
Time (h)
T °C
Yield (%)b
1
2
3
4
5
6
7
8
9
CH CN
DMC
THF
Toluene
DMF
EtOH
12
12
12
12
06
12
12
12
12
80
60
66
100
100
80
100
100
100
10
30
20
40
94
05
Trace
10
20
3
H O
2
H O/DMF (50:50)
2
H O/DMF (20:80)
2
a
Reaction conditions: 4-bromoacetophenone (1.0 mmol), methyl acrylate (1 mmol), Pd–DABCO@SiO (1 mol%), K CO (2.0 mmol), solvent
2
2
3
b
(
5 mL) in an open vessel. Isolated yields based on the aryl halide used
Results and discussion
with prolonged reaction time (Table 1, entry 7). When
the reaction was carried out in H O/DMF mixture, only
2
The preparation and characterization oꢀ the Pd–DABCO@
10–20% yield was observed (Table 1, entries 8, 9).
The selection oꢀ the proper base is crucial ꢀor a success in
Pd-catalyzed cross-coupling reactions [40]. The inꢂuence oꢀ
the choice oꢀ base was investigated by perꢀorming the model
reaction with varying organic and inorganic bases in DMF at
100 °C. We obtained very low yields with organic bases such
as Et3N and DBU (Table 2, entries 3 and 4). It was observed
that 94% yield was obtained in the presence oꢀ K2CO3 as a
base (Table 2, entry 5).
SiO catalyst were perꢀormed ꢀollowing the literature pro-
2
cedure as described in our previous report [37], as sche-
matically represented in Scheme 1. The amount oꢀ Pd in
the catalyst as determined by ICP–AES was ꢀound to be
−
1
0
.075 mmol g oꢀ solid support.
The catalytic activity oꢀ Pd–DABCO@SiO catalyst
2
was studied ꢀor the coupling oꢀ 4-bromoacetophenone
with methyl acrylate as a model reaction using various
bases, solvents and at diꢀꢀerent temperatures. Out oꢀ
various protic and aprotic solvents used [38, 39], DMF
worked well at 100 °C temperature using K CO as a base
The eꢃect oꢀ amount oꢀ catalyst on the percentage conver-
sion oꢀ the model reaction was studied. Thus, among the diꢀ-
ꢀerent catalyst loadings, 1 mol% proved to be the best aꢃord-
ing the desired product in 6 h with 94% yield in DMF at
100 °C (Table 2 entry 5). To study the eꢃect oꢀ temperature
2
3
(
Table 1, entry 5). The catalyst was inactive in an aqueous
medium and gave only trace amounts oꢀ coupling product
1
3

Transition Metal Chemistry
Table 2 Screening oꢀ various reaction conditions ꢀor Mizoroki–Heck reactiona
Entry
Base
Catalyst (mol%)
T °C
Time (h)
Yield (%)b
1
2
3
4
5
6
7
8
9
K PO
NaOH
1.0
1.0
1.0
1.0
1.0
0.5
1.5
1.0
1.0
1.0
100
100
100
100
100
100
100
90
12
12
12
12
06
12
06
12
12
12
56
60
70
65
94
48
94
80
61
32
3
4
Et N
3
DBU
K CO
2
3
K CO
2
3
3
3
3
3
K CO
2
K CO
2
K CO
80
70
2
1
0
K CO
2
a
Reaction conditions: 4-bromoacetophenone (1.0 mmol), methyl acrylate (1 mmol), Pd–DABCO@SiO (0.5–1.5 mol%), base (2.0 mmol), DMF
2
b
(
5 mL) in an open vessel. Isolated yields based on the aryl halide used
on catalytic activity, the model reaction was carried out at
diꢃerent temperatures. As the temperature was reduced ꢀrom
To extend the scope oꢀ our work, a range oꢀ aryl hal-
ides and olefn compounds were examined using 1 mol%
Pd–DABCO@SiO in DMF at 100 °C using K CO as a
1
00 to 70 °C, the reaction time was prolonged 12 h with
2
2
3
low yields (Table 2, entries 8–10). These results indicated
that the temperature oꢀ reaction is crucial ꢀor the catalytic
eꢁciency.
base. Various aryl bromides and olefns reacted smoothly
to aꢃord the desired coupling products in good-to-excel-
lent yields, with the ꢀormation oꢀ only E-isomers (Table 3,
entries 1–17). From a practical point oꢀ view, the utilization
oꢀ the easily available, inactive and inexpensive aryl chlo-
rides is highly desirable, and the catalyst showed moderate
activity giving 39–46% yield oꢀ the desired product in 12 h
(Table 3, entries 22–25). Active aryl iodides and olefns
reacted smoothly as compared with aryl bromides and aryl
chlorides to aꢃord the desired coupling products in good-to-
excellent yields in 4 h (Table 3, entries 18–21).
In the optimization study, the eꢃect oꢀ the reaction time
on the yield oꢀ the fnal product was confrmed ꢀor the cur-
rent model reaction, and the results are presented in Fig. 1.
For this study, the model reaction was carried out in the time
range oꢀ 1–6 h. It was observed that the percentage yield oꢀ
desired product increased with the increase in the reaction
time giving 94% yield in 6 h.
Gram-scale synthesis: As a part oꢀ our ongoing research
in organic synthesis, we report a scalable synthetic approach
ꢀor Mizoroki–Heck cross-coupling reactions by using opti-
mized reaction conditions (Scheme 2). Treatment oꢀ 10 mmol
oꢀ butyl acrylate with various aryl bromides gave good-to-
excellent yields oꢀ the corresponding products. These results
demonstrated the reproducibility and practical method ꢀor
industrial applications.
Catalyst recyclability: The recyclability oꢀ Pd–DABCO@
SiO was investigated with consecutive coupling reactions oꢀ
2
4
-bromoacetophenone with methyl acrylate (Fig. 2). Aꢀter
the frst cycle, the catalyst was separated by centriꢀugation
and washed with water, acetone and dichloromethane. The
catalyst was then dried under vacuum beꢀore perꢀorming
the reusability test and charging with ꢀresh substrate. In this
way, the catalyst was reused ꢀor ten consecutive cycles. As
shown in Fig. 2, the catalyst could be used up to fve times
without signifcant loss oꢀ catalytic perꢀormance as well as
Fig. 1 Eꢃect oꢀ reaction time on the yield oꢀ the desired product
1
3

Transition Metal Chemistry
Table 3 Mizoroki-Heck
reaction oꢀ various aryl halides
and olefns over Pd–DABCO@
SiO
2
Reaction conditions: aryl halides (1 mmol), olefns (1 mmol), Pd–DABCO@SiO (1 mol%), K CO3
2
2
(
2 mmol), DMF (5 mL, 100 °C), under air. Isolated yields aꢀter column chromatography
selectivity. The drop-oꢃ in reactivity oꢀ catalyst aꢀter the
seventh catalytic cycle may be due to the deactivation oꢀ
palladium metal.
Conclusion
In conclusion, Pd–DABCO@SiO catalyst has been suc-
2
cessꢀully synthesized ꢀollowed by known graꢀting chemistry
involving quaternization oꢀ DABCO. The resulting material
was used as a heterogeneous catalyst ꢀor Mizoroki–Heck
1
3

Transition Metal Chemistry
Scheme 2 Gram-scale synthesis
O
Pd-DABCO@SiO2
O
oꢀ acrylate derivatives
Bu
DMF, K2CO3, 100 °C, 6h
O
4
-bromo-
O
4
'-bromo-
Bu
benzophenone
acetophenone
O
O
15 (88 %)
17 (82 %)
O
O
10 mmol
O
1
-bromo-4-
O
chlorobenzene bromobenzene
Bu
Bu
O
O
DMF, K2CO3, 100 °C, 6h
Pd-DABCO@SiO2
Cl
11 (90 %)
3
(90 %)
1
5
00 MHz spectrometer. Chemical shiꢀts ꢀor H NMR are
reꢀerred to internal TMS (0 ppm), and chemical shiꢀts ꢀor
1
3
C NMR are reꢀerred to the carbon resonance oꢀ the sol-
vent (CDCl : δ 77.0 ppm). Data are reported as ꢀollows:
3
chemical shiꢀt (δ ppm), multiplicity (s=singlet, d=doublet,
t=triplet, q=quartet, m=multiplet), coupling constant (Hz)
and integration. Mass spectra were recorded on a Shimadzu
QP2010 GCMS with an ion source temperature oꢀ 280 °C.
All the chemicals were obtained ꢀrom Aldrich and were used
without ꢀurther purifcation.
General procedure for Mizoroki–Heck coupling
reactions
In a Schlenk ꢂask, equipped with a magnetic stir bar,
septum and a condenser were placed the aryl halide
(
1.0 mmol), olefn compound (1 mmol), K CO (2 mmol),
2 3
catalyst (1 mol%) and DMF (5 mL). The ꢀlask was
immersed in an oil bath and a reaction mixture stirred at
Fig. 2 Recycling oꢀ Pd–DABCO@SiO catalyst ꢀor Mizoroki–Heck
2
reaction
1
00 °C. Upon complete consumption oꢀ starting materi-
als as determined by TLC analysis (petroleum ether/ethyl
acetate, 8:2), the catalyst was separated by fltration and
water (20 mL) was added. The fltrate was extracted with
diethyl ether (3×10 mL). The combined organic layer was
collected, dried over anhydrous Na SO and concentrated
coupling reactions oꢀ various aryl halides with olefns to
give the E-isomer selectively in good-to-excellent yields.
The catalyst showed interesting ꢀeatures such as high eꢁ-
ciency, economy and simple reaction processing. Moreo-
ver, easy recovery with recyclability is one oꢀ the additional
advantages oꢀ this catalyst. In addition, the protocol could
be applied ꢀor gram-scale synthesis oꢀ acrylates.
2
4
in vacuum, and the resulting compound was purifed by
column chromatography.
Procedure for preparation of the Pd–DABCO@SiO2
catalyst [37]
Experimental
General remarks
Synthesis of DABCO@SiO2
1
13
H-NMR and C-NMR spectra oꢀ the pure compounds
Activated mesoporous amorphous silica gel (average par-
ticle size 60–120 mesh) (10 g) was heated at 100 °C with
were recorded on a Bruker Avon 200 MHz, 400 MHz or
1
3

Transition Metal Chemistry
DABCO-SIL (3.52 g, 10 mmol) in dry toluene ꢀor 24 h.
The resulting reaction mixture was fltered oꢃ and washed
with hot toluene ꢀor 12 h in a continuous extraction appa-
ratus (Soxhlet) and then dried at 100 °C ꢀor overnight to
give (12.9 g) silica-supported DABCO-SIL.
CDCl ) 52.2, 122.3, 124.5, 128.4, 140.8, 142.0, 149.5,
3
165.9. GCMS C H NO : m/z 207.
1
0
9
4
Methyl(E)‑3‑(4‑ꢀuorophenyl)acrylate (Table 3, entry 9) The
product was purifed by column chromatography on silica
gel 60–120 mesh (hexane/ethyl acetate = 9:1) as a yellow
1
Synthesis of Pd–DABCO@SiO2
oil. H NMR (300 MHz, CDCl ) δ 7.54 (d, J=16.0 Hz, 1H),
3
7
.44–7.38 (m, 2 H), 7.05–6.98 (m, 2H), 6.32 (d, J = 16.0,
1
3
To a solution oꢀ silica-supported DABCO-SIL (2 g) in
1 H), 3.86 (s, 3 H). C NMR (75 MHz, CDCl ) δ 165.3,
3
dry acetone, Pd(OAc) (0.044 g, 0.19 mmol) was added
162.1, 142.3, 129.1, 127.9, 115.4, 114.3, 113.5, 53.2 ppm.
2
and the resulting mixture was stirred at room temperature
MS (ESI) C H FO : m/z 180.
1
0
9
2
ꢀ
or 24 h. The solid product was fltered oꢃ, washed with
acetone, distilled water and acetone successively and dried
under vacuum at 60 °C ꢀor 4 h to give the yellow product
Methyl(E)‑3‑(4‑chlorophenyl)acrylate (Table 3, entry
10) The product was purifed by column chromatography
Pd–DABCO@SiO (2.03 g) which was characterized by
on silica gel 60–120 mesh (hexane/ethyl acetate = 9:1) as
2
1
characterized by analytical methods.
a yellow solid. H NMR (300 MHz, CDCl ) δ 7.72 (d, 1H,
3
J=16.0 Hz), 7.55–7.40 (m, 4 H), 6.44 (d, 1H, J=15.9 Hz),
1
3
Spectroscopic analysis
3.80 (s, 3 H); C NMR (75 MHz, CDCl ) δ 166.3, 142.1,
3
1
37.2, 133.2, 128.7, 126.1, 119.3, 52.7 ppm. MS (ESI)
(
E)‑methyl cinnamate (Table 3, entry 2) The product was
C H ClO : m/z 196.
1
0
9
2
purifed by column chromatography on silica gel 60–120
1
mesh (hexane/ethyl acetate=9:1) as a colorless oil. H NMR
Butyl(E)‑3‑(4‑chlorophenyl)acrylate (Table 3, entry 11) The
(
CDCl , 300 MHz); δ 3.71 (s, 3H), 6.44 (d, 1H, J=15.9 Hz),
product was purifed by column chromatography on silica
3
7
.33 (t, 3H, J=3.3 Hz), 7.50–7.55 (m, 2H), 7.75 (d, 1H,
gel 60–120 mesh (hexane/ethyl acetate = 9:1) as a yellow
13
1
J=15.9 Hz). CNMR (75 MHz, CDCl ) δ 52.1, 112.3, 126.8,
oil. H NMR (300 MHz, CDCl ) δ 7.50 (d, 1H, J=16.0 Hz),
3
3
1
28.01, 136.2, 144.5, 165.6. GCMS C H O : m/z 162.
7.32 (d, 2H, J=8.4 Hz), 7.26 (d, 2H, J=8.3 Hz), 6.28 (d,
10
10
2
1
H, J=15.9 Hz), 4.16 (t, 2H, J=6.3 Hz), 1.67–1.53 (m, 2
1
3
Methyl(E)‑3‑(4‑methoxyphenyl)acrylate (Table 3, entry
H), 1.42–1.35 (m, 2 H), 0.93 (t, 3H, J=7.4 Hz); C NMR
4
) The product was purifed by column chromatography
(75 MHz, CDCl ) δ 165.7, 142.0, 137.2, 132.01, 128.3,
3
on silica gel 60–120 mesh (hexane/ethyl acetate = 9:1)
126.8, 126.2, 116.8, 62.2, 32.8, 18.1, 14.5 ppm. MS (ESI)
1
as a white solid. H NMR (CDCl , 300 MHz): δ 7.63 (d,
C H ClO : m/z 238.
3
13 15
2
1
H, J = 16.0 Hz), 7.42 (d, 2H, J = 8.1 Hz), 6.89 (d, 2H,
J = 8.03 Hz), 6.33 (d, 1H, J = 16.01 Hz), 3.86 (s, 3 H),
(E)‑1‑(4‑styrylphenyl)ethanone (Table 3, entry 12) The prod-
1
3
3
1
.78 (s, 3 H); C NMR (CDCl , 75 MHz): δ 166.6, 162.3,
uct was purifed by column chromatography on silica gel
3
45.2, 130.6, 126.2, 117.1, 112.2, 54.2, 50.7 ppm. MS (ESI)
60–120 mesh (hexane/ethyl acetate=9:1) as a white solid.
1
C H O : m/z 192.
H NMR (CDCl 300 MHz) δ (ppm) 2.60 (s, 3H), 7.25 (d,
1
1
12
3
3
1
H, J = 16.2 Hz), 7.35–7.44 (m, 3H), 7.54–7.59 (m, 2H),
Methyl(E)‑3‑(p‑tolyl)acrylate (Table 3, entry 5) The prod-
7.62 (d, 2H, J=8.4 Hz), 7.93 (d, 1H, J=15.9 Hz), 7.96 (d,
1
3
uct was purifed by column chromatography on silica gel
2H, J=8.6 Hz). C NMR (75 MHz, CDCl ): δ 26.1, 125.5,
3
6
0–120 mesh (hexane/ethyl acetate=9:1) as a colorless oil.
126.3, 128.4, 130.3, 131.8, 131.5, 132.1, 136.9, 137.7,
1
H NMR (300 MHz, CDCl ) δ 7.71 (d, 1H, J = 16.0 Hz),
143.0, 196.4. MS (ESI) C H O: m/z 222.
3
16 14
7
.40 (d, 2H, J=8.2 Hz), 7.19 (d, 2H, J=8.1 Hz), 6.41 (d,
1
3
1
H, J = 16.1 Hz), 3.82 (s, 3 H), 2.34 (s, 3 H); C NMR
(E)‑methyl‑3‑(4‑acetophenonyl)acrylate (Table 3, entry
13) The product was purifed by column chromatography
(
75 MHz, CDCl ) δ 168.3, 145.2, 141.7, 135.2, 131.3, 129.1,
3
1
15.4, 52.8, 22.3 ppm. MS (ESI) C H O : m/z 176.
on silica gel 60–120 mesh (hexane/ethyl acetate = 9:1) as
1
1
12
2
1
a white solid. H NMR (CDCl , 300 MHz) δ (ppm) 2.62
3
(
E)‑p‑nitromethyl cinnamate (Table 3, entry 7) The prod-
(s, 3H), 3.88 (s, 3H), 6.55 (d, 1H, J = 15.9 Hz), 7.62 (d,
uct was purifed by column chromatography on silica gel
2H, J = 8.1 Hz), 7.72 (d, 1H, J = 16.2 Hz), 7.97 (d, 2H,
13
6
0–120 mesh (hexane/ethyl acetate=9:1) as a yellow solid.
J=8.4 Hz). CNMR (75 MHz, CDCl ): δ (ppm), 28.6, 52.8,
3
1
H NMR (CDCl , 300 MHz) δ (ppm) 3.80 (s, 3H), 6.55
121.3, 128.5, 128.9, 130.5, 139.7, 144.2, 165.8, 196.1. MS
3
(
d, 1H, J=16.2 Hz), 7.67–7.70 (m, 2H, J=9 Hz), 7.76 (d,
(ESI) C H O : m/z 204.
1
2
12
3
1
3
1
H, J=16.2 Hz), 8.28–8.25 (m, 2H). C NMR (75 MHz,
1
3

Transition Metal Chemistry
Ethyl(E)‑3‑(4‑acetylphenyl)acrylate (Table 3, entry 14) The
Ethyl(E)‑3‑(4‑nitrophenyl)acrylate (Table 3, entry 21) The
product was purifed by column chromatography on silica
product was purifed by column chromatography on silica
gel 60–120 mesh (hexane/ethyl acetate = 9:1) as a yellow
gel 60–120 mesh (hexane/ethyl acetate = 9:1) as a yellow
1
1
solid. H NMR (300 MHz, CDCl ) δ 7.82 (d, 2H, J=8.1 Hz),
solid. H NMR (200 MHz, CDCl ) δ 8.32 (d, 2H, J=8.4 Hz),
3
3
7
.54 (d, 1H, J=16.0 Hz), 7.47 (d, 2H, J=8.0 Hz), 6.45 (d,
7.84–7.75 (m, 3 H), 6.58 (d, 1H, J=15.9 Hz), 4.34 (q, 2H,
1
3
1
H, J=15.9 Hz), 4.19 (q, 2H, J=7.2 Hz), 2.48 (s, 3 H), 1.28
J = 7.4 Hz), 1.38 (t, 3H, J = 7.3 Hz); C NMR (50 MHz,
1
3
(
t, 3H, J = 8.2 Hz); C NMR (75 MHz, CDCl ) δ 196.3,
CDCl ) δ 165.2, 147.3, 140.5, 138.6, 130.6, 126.3, 124.5,
3
3
1
1
65.4, 140.7, 136.6, 136.4, 127.2, 127.2, 117.8, 61.6, 24.6,
4.5 ppm; MS (ESI) C H O : m/z 218.
60.2, 13.9 ppm. MS (ESI) C H NO : m/z 221.
1
1
11
4
1
3
14
3
Methyl(E)‑3‑(4‑chlorophenyl)acrylate (Table 3, entry
24) The product was purifed by column chromatography
Butyl(E)‑3‑(4‑acetylphenyl)acrylate (Table 3, entry 15) The
product was purifed by column chromatography on silica
on silica gel 60–120 mesh (hexane/ethyl acetate = 9:1) as
1
gel 60–120 mesh (hexane/ethyl acetate=9:1) as a colorless
a yellow solid. H NMR (200 MHz, CDCl ) δ 7.76 (d, 1H,
3
1
oil. H NMR (300 MHz, CDCl ) δ 7.96 (d, 2H, J=8.2 Hz),
J=16.0 Hz), 7.58–7.44 (m, 4 H), 6.46 (d, 1H, J=15.9 Hz),
3
1
3
7
.65 (d, 1H, J = 16.1 Hz), 7.54 (d, 2H, J = 8.2 Hz), 6.42
3.84 (s, 3 H); C NMR (50 MHz, CDCl ) δ 164.2, 142.8,
3
(
d, 1H, J = 15.9 Hz), 4.12 (t, 2H, J = 6.4 Hz), 2.50 (s, 3
135.3, 134.5, 128.4, 127.2, 116.3, 52.6 ppm. MS (ESI)
H), 1.68–1.52 (m, 2 H), 1.48–1.34 (m, 2 H), 0.86 (t, 3H,
C H ClO : m/z 196.
1
0
9
2
1
3
J = 7.3 Hz); C NMR (75 MHz, CDCl ) δ 198.3, 166.8,
3
1
2
42.1, 137.3, 136.2, 126.2, 125.1, 121.7, 62.6, 30.2, 24.5,
0.1, 14.6 ppm; MS (ESI) C H O : m/z 246.
Acknowledgements Author Sanjay Jadhav thanks the University
1
5
18
3
Grants Commission, New Delhi, India, ꢀor the award oꢀ SAP-BSR
ꢀellowship.
Methyl(E)‑3‑(4‑benzoylphenyl)acrylate (Table 3, entry
1
6) The product was purifed by column chromatography
Compliance with ethical standards
on silica gel 60–120 mesh (hexane/ethyl acetate=9:1) as a
1
white solid. H NMR (300 MHz, CDCl ) δ 7.83–7.75 (m,
3
Conflicts of interest The authors declare that they have no conꢂict oꢀ
4
H), 7.74–7.61 (m, 4 H), 7.66–7.54 (m, 2 H), 6.52 (d, 1H,
interest.
1
3
J = 15.9 Hz), 3.82 (s, 3 H); C NMR (75 MHz, CDCl )
3
δ 197.2, 163.9, 142.2, 137.5, 136.2, 135.3, 131.6, 129.5,
1
2
29.0, 127.4, 127.1, 18.7 ppm; MS (ESI) C H O : m/z
References
1
7
14
3
66.
1
2
.
.
Barnard C (2008) Platin Metals Rev 52:38
Nicolaou K, Bulger P, Sarlah D (2005) Angew Chem Int Ed
Butyl(E)‑3‑(4‑benzoylphenyl)acrylate (Table 3, entry 17) The
4
4:4442
product was purifed by column chromatography on silica gel
3
.
Chen X, Engle K, Wang D-H, Yu J-Q (2009) Angew Chem Int Ed
48:5094
6
0–120 mesh (hexane/ethyl acetate=9:1) as a white solid.
1
4. Chianese A, Lee S, Gagn M (2007) Angew Chem Int Ed 46:4042
H NMR (300 MHz, CDCl ) δ 7.82–7.74 (m, 4 H), 7.67–
3
5
6
7
8
.
.
.
.
Lewis L, Stein J, Gao Y, Colborn R, Hutchins G (1997) Platin
Metals Rev 41:66
7
.55 (m, 4 H), 7.52–7.44 (m, 2 H), 6.52 (d, 1H, J=16.1 Hz),
4
2
.22 (t, 2H, J=4.3 Hz), 1.71–1.61 (m, 2 H), 1.58–1.40 (m,
Zanotti-Gerosa A, Hems W, Groarke M, Hancock F (2005) Platin
Metals Rev 49:158
1
3
H), 0.93 (t, 3H, J=4.3 Hz); C NMR (75 MHz, CDCl )
3
Minenkov Y, Occhipinti G, Jensen V (2013) Organometallics
δ 196.9, 166.5, 142.2, 137.4, 137.2, 131.6, 130.3, 129.0,
3
2:2099
1
27.8, 127.4, 119.7, 62.7, 32.3, 18.2, 14.7 ppm; MS (ESI)
Evans D, Fu G (1990) J Org Chem 55:2282
C H O : m/z 308.
2
0
20
3
9. Jadhav S, Rode C (2017) Green Chem 19:5958
1
0. Wagaw S, Buchwald S (1996) J Org Chem 61:7240
1. Hartwig J (2008) Nature 455:314
1
1
1
1
Methyl(E)‑3‑(4‑methoxyphenyl)acrylate (Table 3, entry
2
2. Zhang W, Nagashima T (2006) J Fluor Chem 127:588
3. Yin L, Liebscher J (2007) Chem Rev 107:133
4. Whitcombe N, Hii K, Gibson S (2001) Tetrahedron 57:7449
0) The product was purifed by column chromatography
on silica gel 60–120 mesh (hexane/ethyl acetate = 9:1)
1
as a white solid. H NMR (CDCl , 200 MHz): δ 7.60 (d,
15. Wellington K, Benner S (2006) Nucleosides, Nucleotides Nucleic
Acids 25:1309
3
1
H, J = 16.0 Hz), 7.44 (d, 2H, J = 8.2 Hz), 6.92 (d, 2H,
1
1
6. Han F-S (2013) Chem Soc Rev 42:5270
J=8.2 Hz), 6.32 (d, 1H, J=15.9 Hz), 3.80 (s, 3 H), 3.76 (s,
7. Biꢁs A, Zecca M, Basato M (2001) J Mol Catal A: Chem 173:249
1
3
3
1
H); C NMR (CDCl , 50 MHz): δ 166.5, 160.3, 143.4,
3
18. Lindh J, Enquist P-A, Pilotti Å, Nilsson P, Larhed M (2007) J Org
Chem 72:7957
28.6, 126.2, 116.3, 113.2, 56.2, 52.4 ppm. MS (ESI)
1
2
9. Du X, Suguro M, Hirabayashi K, Mori A (2001) Org Lett 3:3313
0. Oi S, Sakai K, Inoue Y (2005) Org Lett 7:4009
C H O : m/z 192.
1
1
12
3
1
3

Transition Metal Chemistry
2
2
1. Jadhav S, Kumbhar A, Mali S, Hong C, Salunkhe R (2015) New
J Chem 39:2333
32. Masoa P, Emslie N (1994) Tetrahedron 50:12001
33. Baghernejad B (2010) Eur J Chem 1:232
34. Li J-H, Li J-L, Wang D-P, Pi S-F, Xie Y-X, Zhang M-B, Hu X-C
(2007) J Org Chem 72:2053
2. Jadhav S, Kumbhar A, Rode C, Salunkhe R (2016) Green Chem
1
8:1898
2
2
2
3. Zhu M, Diao G (2011) J Phys Chem C 115:24743
4. Kumbhar A (2017) Top Curr Chem 375:2
35. Shi Y-L, Shi M (2005) Org Lett 7:3057
36. Li J-H, Liu W-J (2004) Org Lett 6:2809
5. Polshettiwar V, Lenb C, Fihri A (2009) Coord Chem Rev
37. Kumbhar A, Kamble S, Jadhav S, Rashinkar G, Salunkhe R
(2012) Catal Lett 142:1388
2
53:2599
2
2
6. Aksın O, Tu¨rkmen H, Artok L, Cetinkaya B, Ni C, Buyukgungor
O, Ozkal E (2006) J Organomet Chem 691:3027
38. Proutiere F, Schoenebeck F (2011) Angew Chem Int Ed 50:8192
39. Yan N, Yang X, Fei Z, Li Y, Kou Y, Dyson P (2009) Organometal-
lics 28:937
7. Ibrahim M, Suleiman R, Fettouhi M, El Ali B (2017) Transit Met
Chem 42:1
40. Li J-H, Hu X-C, Liang Y, Xie Y-X (2006) Tetrahedron 62:31
2
2
8. Urgaonkar S, Xu J-H, Verkade J (2003) J Org Chem 68:8416
9. Jadhav S, Kumbhar A, Salunkhe R (2015) Appl Organomet Chem
Publisher’s Note Springer Nature remains neutral with regard to
2
9:339
jurisdictional claims in published maps and institutional aꢁliations.
3
3
0. Mandal S, Roy D, Chaudhari R, Sastry M (2004) Chem Mater
6:3714
1. Jiang Y, Gao Q (2006) J Am Chem Soc 128:716
1
1
3