Highly efficient three-component coupling reaction catalyzed by gold nanoparticles supported on periodic mesoporous organosilica with ionic liquid framework

Article abstract of DOI:10.1039/c2cc33320a

A novel gold nanoparticle supported periodic mesoporous organosilica with alkylimidazolium framework, Au@PMO-IL, was shown to be a highly active and recyclable catalyst for three-component coupling reaction of aldehyde, alkyne and amine to give the corresponding propargylamine.

Full text of DOI:10.1039/c2cc33320a

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ARTICLE TYPE
Highly Efficient Three-Component Coupling Reaction Catalyzed by
Gold Nanoparticles Supported on Periodic Mesoporous Organosilica
with Ionic Liquid Framework†
Babak Karimi,* Mohammad Gholinejad* and Mojtaba Khorasani
Received (in XXX, XXX) XthXXXXXXXXX 20XX, Accepted Xth XXXXXXXXX 20XX
5
DOI: 10.1039/b000000x
recently, Vinu and co-workers reported a new promising catalyst 45
system comprising gold nanoparticles embedded in mesoporous
carbon nitride for the synthesis of propargylamines through A3
coupling reaction.17g While this method provide an excellent
approach in preventing the agglomeration of Au nanoparticles
during the A3 coupling reaction, low selectivity of the products 50
considerably limits the versatility of this catalytic system.
Therefore, it seems that quest for novel, efficient and recoverable
Au-based catalysts for A3 coupling reactions with appropriate
selectivity remains a great challenge.
A novel gold nanoparticles supported on periodic mesoporous
organosilica with alkylimidazolium framework, Au@PMO-
IL, was shown to be highly active, and recyclable catalyst for
three-component coupling reaction of aldehyde, alkynes and 10
amines to give the corresponding propargylilc amine.
In the past few years, an increasing number of multicomponent
reactions (MCRs) have developed for the synthesis of diverse
complex molecules through a combination of three or more
starting material in one-pot operation, while keeping reduced 15
waste and increased safety.1 Among MCRs, the catalytic coupling
reaction of aldehyde, amine, and alkyne (A3 coupling) is one of
the best example, where propargylamine is obtained as the major
product. Propargylamines are valuable synthetic building blocks
in synthesis of varied natural products and biologically active 20
compounds.2-3 Numerous method typically involve C-H bond
activation of terminal alkynes using a wide range of transition-
metal catalyst such as copper,4 iridium,5 nickel,6 iron,7 and
indium8 have been well explored for the synthesis of
Herein, we report that a novel gold nanoparticles supported on 55
periodic mesoporous organosilica with imidazolium ionic liquid
framework having 2D-hexagonal structure is an efficient and
highly selective catalyst in the three-component coupling
reactions of aldehydes, terminal alkynes, and amines at very low
catalyst loading and under mild reaction conditions. Synthesis of 60
periodic mesoporous organosilica containing ionic liquid (PMO-
IL) has been introduced recently by our research group.18 In this
regard,
hydrolysis
and
co-condensation
of
1,3-
propargylamines.
25
bis(trimethoxysilylpropyl) imidazolium chloride and tetra
methoxysilane in the presence of P123 as structure directing 65
agent under acidic conditions afforded the corresponding PMO-
IL. We also investigated the ability of the obtained mesoporous
organosilicas to actually use as a support for the immobilization
and stabilization of Pd-nanoparticles in the Suzuki-coupling
reaction of aryl halides with arylboronic acids and aerobic 70
oxidation of alcohols under mild reaction conditions. Considering
the ionic nature of bridge organic group in our PMO-IL, we
reasoned that the materials might be indeed utilized to support
Although for a long time gold has been regarded as a poor or
even inactive catalyst, during the past decade increasing
attentions have been directed toward both chemistry and catalytic
performance of this metal. A major driving force for this interest
is owing to the fact that gold have demonstrated unusual and 30
somewhat unexpected catalytic properties in many chemical
transformations as underscored by appearing several excellent
reviews in this field.9 Quite recently, surface structures and
electronic properties of various gold single-crystal surfaces10 and
different application of gold as a catalyst were studied.11 In this 35
regards, oxidation of alcohols and carbon monoxide under mild
conditions,12 hydrogenation of olefins,13 Suzuki,14 Sonogashira15
and Ullman16 coupling reactions, etc. are some of the most
important applications of gold catalysts. Meanwhile, it was also
found that Lewis acid character and unique property of gold in 40
activating sp and (even sp2and sp3) C-H bonds make it as a
promising catalyst in three-component condensation reaction of
terminal alkynes with aldehydes and amines.17 Nevertheless,
reports of using gold as a catalyst are still very limited. Quite
-
anionic gold species like AuCl4 via a simple ion exchange
reaction. To verify our hypothesis, a dispersion of PMO-IL (0.5 75
g, 0.5 mmol imidazolium g-1) was sonicated in deionized water
(10 ml) for 10 minutes. A solution of NaAuCl4 (0.034 g, 0.085
mmol) in deionized water was gradually added to the suspension
while stirring at the room temperature for 4 hours. Assuming that
all AuCl4- were exchanged with the available amount of Cl- in the 80
original PMO-IL, one would expect an Au content of
approximate 0.16 mmol g-1 in the resulting hybrid materials, a
value which was confirmed by atomic adsorption spectroscopy.
[journal], [year], [vol], 00–00 |1
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Table 2. Three-component reaction of various aldehyde, secondary
amines and terminal alkynes catalyzed by Au@PMO-ILa
The FT-IR of the catalyst was studied (Figure 1S). The peaks at
1565 cm-1 and 1633cm-1in the spectrum of the initial PMO-IL is
attribute to C=C and C=N stretching bonds of imidazolium ring,
respectively.17 This indicates that ionic liquid precursor was
incorporated into the PMO-IL material and remains intact into
PMO matrix after both sol-gel process and surfactant extraction.
The nitrogen adsorption-desorption isotherm of both PMO-IL and
Au@PMO-IL exhibited type-IV curves with sharp type H1
hysteresis loop, thus implying the cylindrical mesoporous with
45
5
Entry
R1
R2 NH
R3
Time(h)
Yield
2
1
2
Ph
Piperidine
Morpholine
Piperidine
Morpholine
Morpholine
Piperidine
Piperidine
Piperidine
Piperidine
Morpholine
Piperidine
Morpholine
Morpholine
Piperidine
Piperidine
Ph
12
12
11
15
20
20
20
15
7
87
86
88
82
87
82
83
78
86
84
85
85
75
88
83
84
81
77
80
Ph
Ph
3
4-Me-C6H4
4-Me-C6H4
2-Thiophenyl
2-Thiophenyl
1-Naphthyl
3-Me-C6H4
2-Cl-C6H4
2-Cl-C6H4
2-Furfuryl
2-Furfuryl
Heptyl
Ph
relatively uniform pore size distribution (Figure 2S). The BET 10
surface area, as well as mesoporous volume of Au@PMO-IL was
calculated to be 516 m2 g-1 and 1.00 cm3 g-1, respectively. The
values were lower than that calculated for PMO-IL (SBET= 554
m2 g-1, Vp= 1.06 cm3 g-1), which highlight the notion that
4
Ph
5
Ph
6
Ph
7
Ph
8
Ph
-
9
Ph
exchange of AuCl4 with Cl- might be significantly accrued into 15
10
11
12
13
14
15
16
17
18
Ph
10
17
20
10
10
11
10
20
12
12
the nanosized pores of the mesoporous materials. The average
pore size diameter of PMO-IL and Au@PMO-IL were calculated
be 5.29 nm using BJH methods, which furthermore affirm the
narrow pore size distributions in the samples. The TEM images
of both samples also revealed regular arrangements of hexagonal 20
tubules having channel dimension of ~ 5 nm, which is in good
agreement with the results obtained by N2 adsorption-desorption
analysis. We were next very interested to examine the catalytic
efficiency of the as-synthesized Au@PMO-IL in A3 coupling
Ph
Ph
Ph
Ph
4-OMe-C6H4
4-OMe-C6H4
4-Me-C6H4
Ph
Morpholine 4-OMe-C6H4
Piperidine 4-OMe-C6H4
1-Naphthyl
Heptyl
Morpholine 4-OMe-C6H4
Morpholine 4-OMe-C6H4
19 2-pheny ethyl
a)
Condition: aldehyde (1 eq.), amine (1.2 eq.), alkyne (1.3eq) and
Au@PMO-IL (12 mg, 0.2 mol% Au) in 5 ml CHCl3 at 60 °C.
reaction of phenyl acetylene with varied aldehyde and amines.
25
Table 1. The effects of various variables on [A3] three-component of 4-
methylbenzaldehyde, piperidine, and phenylacetylene using Au@PMO-
ILa)
Having the optimized reaction condition, it was then attempted to
expand the scope of amines, aldehydes and terminal alkynes 50
applicable to the present A3 coupling reaction as demonstrated in
Table 2. From these results we found that the conditions were
equally applicable to the coupling a variety of aromatic aldehydes
including heterocyclic aldehydes as well as 1-naphtaldehyde with
either morpholine or piperidine utilizing phenyl acetylene, giving 55
the corresponding propargylamines in high yields (Scheme 1,
Table 2, entries 1-13). As demonstrated in Table 2, this reaction
successfully works for coupling of of aromatic aldehydes with
both piperidine and morpholine by 4-methoxy phenyl acetylene
as carbon nucleophile partner, affording 4-methoxy propargylic 60
amines in excellent as well (Table 2, entries 14-19).
Entry
Solvent
T (°C)
Isolated Yield
1
2
3
4
5
6
7
8
9
Toluene
Water
60
60
45
55
CHCl3
60
88
Solvent-free
PEG (200)
CH3CN
Toluene
Water
60
50
60
Trace
trace
65
60
100
100
25
In order to show the practical applicability of the Au@PMO-IL,
we have scaled up the reaction of benzaldehayde to 10 mmol with
12 mmol of piperidine and 13 mmol of phenyl acetylene under
similar optimized reaction conditions. The reaction proceeds well 65
with 92 isolated yields at 11 h.
70
CHCl3
30
a)Condition: aldehyde (1 eq.), amine (1.2 eq.), alkyne (1.3eq) and 30
Au@PMO-IL (12 mg, 0.2 mol% Au) in 5 mL solvent for 11 h.
Furthermore, the Au@PMO-IL is stable and reusable up to three
reaction runs, giving an average of 83% isolated yields under the
described conditions. Our investigation showed that although the
recovered catalyst exhibited very slowly decreasing activity in 70
several consecutive runs, in each cycle the metal leaching was
negligible. Moreover, no appreciable changes in textural
properties after three reactions cycle has been detected as clearly
evidenced from N2 adsorption-desorption (Figure 2S) and TEM
analysis of the recycled catalyst (Figure 1). TEM images also 75
indicate no detectable Au nanoparticles aggregation in the
recovered Au@PMO-IL after the 3rd reaction run. Based on TEM
images it is believe that integrated ionic liquid units (imidazolium
units) incorporated in the mesochannels of PMO-IL may indeed
We focused our initial investigation on the effect of various types
of solvents on the reaction of p-tolualdehyde, piperidine, and
phenyl acetylene at different temperatures (Table 1).The results 35
indicate that both reaction temperature, type of solvent used
significantly influence the product yields in the described
coupling reaction (Table 1). After several screening experiment
with different combinations of the above-mentioned variable, the
best condition was proved to be Au@PMO-IL (12 mg, 0.2 mol% 40
of Au), p-tolualdehyde (1mmol), piperidine (1.2 mmol),
phenylacetylene (1.3mmol), CH3Cl (5 ml) at 60 °C during 11 h.
2
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a) B. Ringdahl, The Muscarinic Receptors, J. H. Brown, (ed.); 50
2
provide a means of generating and stabilizing active catalytic
AuNPs species during the described reaction.
Humana Press Inc., Clifton NJ, 1989; b) D. P. Zlotos, W. Bender and
U. Holzgrabe, Exp. Opin. Ther. Patents, 1999, 9, 1029.
3
4
W. Tatton, R. Chalmers-Redman and N. Tatton, J Neural Transm.,
2003, 110, 509.
L. Shi, Y.-Q. Tu, M. Wang, F.-M. Zhang and C.-A.Fan, Org. Lett. 55
2004, 6, 1001; b) M. J. Aliaga, D. J. Ramon and M. Yus, Org.
Biomol. Chem., 2010, 8, 43; c) M. L. Kantam, J. Yadav, S. Laha and
S. Jha, Synlett, 2009, 1791; c) L. Shi, Y.-Q. Tu, M. Wang, F.-M.
Zhang and C.-A. Fan, Org. Lett., 2004, 6, 1001; d) S. Nakamura, M.
Ohara, Y. Nakamura, N. Shibata and T. Toru, Chem. Eur. J. 2010, 60
16, 2360; e) T. Zeng, L. Yang, R. Hudson, G. Song, A. R. Moores
and C.-J. Li, Org. Lett., 2011, 13, 442; f) H. Sharghi, R. Khalifeh, F.
Moeini, M. H. Beyzavi, A. SalimiBeni and M. M. Doroodmand, J.
Iran. Chem. Soc., 2011, 8, 89; g) C. Wei and C.-J. Li, J. Am. Chem.
Figure 1. TEM image of Au@PMO-IL after the 3rd reaction cycle (Scale
5
Soc. 2002, 124, 5638.
65
bar: 100 nm).
5
6
S. Sakaguchi, T. Kubo and Y. Ishii, Angew. Chem.Int. Ed., 2001,
113, 2602.
K. Namitharan and K. Pitchumani, Eur. J. Org. Chem. 2010, 411.
It has been well-documented that cationic gold species in the
form of either AuI or AuIII exhibit higher catalytic performance
7. a) T. Zeng,W,-W. Chen, C. M. Cirtiu, A. Moores, G. Songand C.-J
Li, Green Chem., 2010, 12, 570; b) P. Li, Y. Zhang and L. Wang, 70
Chem. Eur. J. 2009, 15, 2045.
than metallic gold in the A3 coupling reactions. To assess whether 10
the cationic gold species are functioning as actual catalyst in our
system or not, we have prepared a reduced Au@PMO-IL sample
by treating the pristine catalyst with an excess of NaBH4. We
interestingly found that this catalyst system provided significantly
decreased conversion (<15%) as compared to untreated 15
Au@PMO-IL (88 %) when using in the A3 Coupling of p-
tolualdehyde with piperidine and phenyl acetylene under
essentially identical conditions. To gain more insight into the
exact gold oxidation state in our catalyst, we have studied both
the pristine Au@PMO-IL and the reduced catalyst by employing 20
X-ray photoelectron spectroscopy (XPS) analysis. XPS spectra of
the region corresponding to the binding energy range of 80-90 eV
for both materials were recorded, which include Au 4f5/2, and Au
4f7/2 peaks. The peaks located around 83.0/86.8 eV and 85.2/88.9
eV were assigned to the spin–orbit splitted components of the Au 25
4f level in the pure Au metalic form (84 eV for pure bulk metallic
Au) and cationic Au(III) species, respectively.19 This spectrum
clearly indicates the reduced samples (inactive catalyst) contained
only Au0 species, whereas the pristine catalyst is only comprising
ionic Au(III) species. In the basis of this observation it is very 30
likely that ionic gold species most probably in the form of Au(III)
is the active component in our active catalyst system, while we
could not exclude some catalysis by metallic gold.
8
9
Y. Zhang, P. Li, M. Wang and L. Wang, J. Org. Chem. 2009, 74,
4364.
a) D. J. Gorinl and F. Dean Toste, Nature, 2007, 446, 395; b) A.
Corma and H. Garcia, Chem. Soc. Rev., 2008, 37, 2096; c) A. Corma, 75
A. Leyva-Perez and M; J. Sabater, Chem. Rev., 2011, 111, 1657; d)
A. Stephen, K. Hashmi, Chem. Rev., 2007, 107, 3180.
10 Y. Zhang, X. Cui, F. Shi and Y. Deng, Chem. Rev., 2012, 112, 2467.
11 J. Gong, Chem. Rev., 2012, 112, 2987.
12 a) C. D. Pina, E. Falletta and M. Rossi, Chem. Soc. Rev., 2012, 41, 80
350; b) C. D. Pina, E. Falletta, L. Prati and M. Rossi, Chem. Soc.
Rev., 2008, 37, 2077; c) B. K. Min and C. M. Friend, Chem. Rev.,
2007, 107, 2709; d) B. Karimi and F. K. Esfahani, Chem. Commun.,
2009, 5555. e) B. Karimi and F. K. Esfahani, Adv. Synth. Catal.
2012, 354, 1319.
85
13 M. Ewana, M. Juliusa, S. Robertsa and J. C.Q. Fletcher, Gold Bull.,
2010,43, 298.
14 a) K. M. Parida, S. Singha, P.C. Sahoo, S. Sahu, J. Mol. Catal. A:
Chem. 2011, 342–343, 11; b) J. Han, Y. Liu and R. Guo, J. Am.
Chem. Soc. 2009, 131, 2060; c) C. González-Arellano, A. Corma, M. 90
Iglesias, F. Sánchez, J. Catal.2006, 238, 497–501; d) Y. Li, X. Fan, J.
Qi, J. Ji, S. Wang, G. Zhang and F. Zhang, Mat. Res. Bull. 2010, 45,
1413.
15 a)T. Lauterbach, M. Livendahl, A. Rosellon and P. Espinet, Org.
Lett., 2010, 12, 3006; b) S. K. Beaumont, G. Kakou, R. M. Lambert 95
and A. M. Echavarren, J. Am. Chem. Soc. 2010, 132, 12246; c) C.
Gonzalez-Arellano, A. Abad, A. Corma, H. Garcia, Angew. Chem.
Int. Ed. 2007, 46, 1536; d) V. K. Kanuru, G. Kyriakou, S. K.
Beaumont, A. C. Papageorgiou, D. J. Watson and R. M. Lambert, J.
Am. Chem. Soc. 2010, 132, 8081; e) P. Li, L. Wang, M. Wang and 100
Feng You, Eur.J. Org. Chem. 2008, 5946; f) A. Corma, R. Juarez, M.
Boronat, F. Sanchez, M. Iglesiasc and H. Garcıa, Chem. Commun.,
2011, 47, 1446.
The authors acknowledge IASBS Research Councils and Iranian
National Science Foundation (INSF) for support of this work. We 35
also appreciate Dr. H. Vali from McGill University for TEM
analysis
16 B. Karimi, and F. K. Esfahani, Chem. Commun., 2011, 47, 10452.
17 a) C. Wei and C.-J. Li, J. Am. Chem. Soc. 2003, 125, 9584; b) B. 105
Huang, X. Yao and C.-J. Li, Adv. Synth. Catal. 2006, 348, 1528; c)
V. K.-Y. Lo, Y. Liu, M.-K. Wong and C.-M. Che, Org. Lett., 2006, 8,
1529; d) L. L. Chng, J. Yang, Y. Wei and J. Y. Ying, Adv.
Synth.Catal. 2009, 351, 2887;e) B. T. Elie, C. Levine, I. Ubarretx-
Belandia, A. Varela-Ramírez, R. J. Aguilera, R. Ovalle and M. 110
Contel, Eur. J. Inorg. Chem. 2009, 3421; f) X. Zhang and A. Corma,
Angew. Chem. 2008, 120, 4430; g) K. K. R. Datta, B. V. S. Reddy, K.
Ariga and A. Vinu, Angew. Chem. Int. Ed. 2010, 49, 5961; h) Y.
Suzuki, S. Naoe, S. Oishi, N. Fujii, and H. Ohno. Org. Lett., 2012,
Notes and References
aDepartment of Chemistry, Institute for Advanced Studies in Basic
Sciences (IASBS), PO-Box 45195-1159, Gava zang, Zanjan 45137-6731, 40
Iran. Fax: +98-241-4214949; Tel: 241 415-3133; E-mail:
karimi@iasbs.ac.ir and gholinejad@iasbs.ac.ir
†
Electronic Supplementary Information (ESI) available: [The
experimental details for the preparation of catalyst, TEM images, FT-IR
14, 326.
115
spectrum for PMO-IL and Au@PMO-IL, XPS spectra, nitrogen 45
adsorption-desorption isotherms, 1H- and 13C-NMR for products]
See DOI: 10.1039/b000000x/
18 a) B. Karimi, D. Elhamifar, J. H. Clark, and A. J. Hunt, Chem. Eur. J.
2010, 16, 8047-8053; b) B. Karimi, D. Elhamifar, J. H. Clark and A.
J. Hunt. Org. Biomol. Chem. 2011, 9, 7420.
1
M. Syamala, Organic Preparations and Procedures International,
2009, 41, 1.
19. B. Koslowski, H. G. Boyen, C. Wilderotter, G. Kastle, P. Ziemann, R.
Wahrenberg and P. Oelhafen, Surf. Sci. 2001, 475, 1
120
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Graphical Abstract