Nano CoFe2O4 supported antimony(III) as an efficient and recyclable catalyst for one-pot three-component synthesis of multisubstituted pyrroles

Article abstract of DOI:10.1039/c3ra47855f

A novel magnetic nano-CoFe₂O₄ supported Sb ([CoFe₂O₄@SiO₂-DABCO-Sb]) was successfully constructed, which exhibited high catalytic activity for one-pot three-component synthesis of multisubstituted pyrroles in the reaction of amines, nitroolefin and 1,3-dicarbonyl compounds. The magnetic heterogeneous catalyst could be easily recovered using an external magnet and reused many times without significant loss of catalytic activity. This journal is the Partner Organisations 2014.

Full text of DOI:10.1039/c3ra47855f

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Nano CoFe2O4 supported antimony(III) as an
efficient and recyclable catalyst for one-pot three-
component synthesis of multisubstituted pyrroles†
Cite this: RSC Adv., 2014, 4, 12929
*
Bao-Le Li, Hai-Chuan Hu, Li-Ping Mo and Zhan-Hui Zhang
A
novel magnetic nano-CoFe2O4 supported Sb ([CoFe2O4@SiO2–DABCO–Sb]) was successfully
Received 21st December 2013
Accepted 18th February 2014
constructed, which exhibited high catalytic activity for one-pot three-component synthesis of
multisubstituted pyrroles in the reaction of amines, nitroolefin and 1,3-dicarbonyl compounds. The
magnetic heterogeneous catalyst could be easily recovered using an external magnet and reused many
times without significant loss of catalytic activity.
DOI: 10.1039/c3ra47855f
www.rsc.org/advances
antioxidant, and antifungal properties.8 Furthermore, the pyrrole
ring has been frequently found in a broad range of natural
products and biologically active compounds.9 In addition, pyrrole
Introduction
The development of environmentally benign, sustainable and
efficiently reusable catalysts is considered as a key point of green
chemistry for providing both economic and ecological benets.1
From this aspect, nanocatalysts have received a lot of attention
because of their unusual properties of a larger surface area to
volume ratio which enhanced the contact between reactants and
catalyst. They may effectively bridge the gap between homoge-
neous and heterogeneous catalysis due to their high dispersion
properties, good catalytic activity and selectivity. Specically,
magnetic nanocatalysts are the most interesting owing to their
easy and efficient isolation and recovery with an external
magnetic eld, which avoids loss of the catalyst associated with
ltration or centrifugation and they have been widely applied in
organic reactions.2–5 Among various magnetic nanoparticles,
cobalt ferrite (CoFe2O4) is a well-known magnetic material with
the properties of high magnetocrystalline anisotropy, moderate
saturation magnetization, excellent chemical stability, low
toxicity, readily accessibility and inexpensiveness which make it
a promising material as catalysts support.6 Recently, anti-
mony(III) chloride has been applied in organic synthesis due to
its accessibility and easier to handle than other metal halides.7
However, antimony trichloride reacts violently with water
because of its property of hygroscopic in the air. The immobi-
lization of antimony(III) chloride on magnetic nanoparticles may
overcome this defect, simplied process set-ups, and eventually
allowed straightforward catalyst recovery and further reuse.
Pyrrole is one of the most important simple heterocycles
owing to its antitumor, anti-inammatory, antibacterial,
derivatives are also particularly important in materials science.10
These utilities continue to drive the interest in the development
of new synthetic methods for pyrroles. The traditional routes to
their preparation are multistep reactions, as illustrated by the
Paal–Knorr cyclization of 1,4-dicarbonyls with ammonia or
primary amines.11 This methods suffer from several drawbacks,
such as stepwise reactions, narrow substrate scope, and lacking
the variation of substituents on the pyrrole ring due to the unity
of starting materials. For all these reasons, the search for new
atom-economical and green synthetic methods, which avoid the
use of special reagents, cost, time, and steps from readily avail-
able and inexpensive materials for the synthesis of functionalized
pyrrole derivatives has attracted much attention.12,13 Very
recently, multicomponent coupling reactions (MCRs) which lead
to the connection of three or more starting materials in a single
synthetic operation with high atom economy and bond-forming
efficiency offer signicant advantages over classical stepwise
methods. For this reasons, the development of new multicom-
ponent reactions is rapidly becoming one of the important tools
in modern organic synthesis.14 Combining both advantages of
multicomponent reaction and the magnetic supported nano-
catalysts, the development of a new atom-efficient and environ-
mentally friendly synthetic procedure for the efficient
preparation of structurally diverse pyrroles is therefore an inter-
esting challenge.
In conjunction with our studies on the design of magnetic
nanocatalysts15 and sustainable synthesis development,16 we
wish to report here a novel magnetic nanoparticle-supported Sb
([CoFe2O4@SiO2–DABCO–Sb]) and its application for the
synthesis of N-protected functionalized pyrroles via three-
component reactions of amines, nitroolen and 1,3-dicarbonyl
compounds (Scheme 1).
College of Chemistry and Material Science, Hebei Normal University, Shijiazhuang
050024, China. E-mail: zhanhui@mail.nankai.edu.cn; Fax: +86 31180787431
† Electronic supplementary information (ESI) available: 1H NMR and 13C NMR
spectra of all compounds. CCDC 964609. For ESI and crystallographic data in
CIF or other electronic format see DOI: 10.1039/c3ra47855f
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Scheme 1 Synthesis of functionalized pyrroles in the presence of
CoFe2O4@SiO2–DABCO–Sb.
Results and discussion
Firstly, we prepared CoFe2O4 nanoparticles as described in our
previous work15d by a chemical co-precipitation technique using
FeCl3$6H2O and CoCl2$6H2O as precursors. CoFe2O4 nano-
particles were easily coated with a layer of SiO2 though chemical
bonds by sonication of CoFe2O4 suspension in a 1 L solution
with the molar composition of 292NH4OH : 1 CTABr : 2773H2O
and tetraethyl orthosilicate (TEOS).17 The obtained CoFe2O4@
SiO2 was then treated with an excess amount of 3-chlor-
opropyltrimethoxysilane and triethylamine in dry toluene at
110 ꢀC to give CoFe2O4@SiO2 bonded 3-propylchloride.18 Then,
3-chloropropyl CoFe2O4@SiO2 reacted with 1,4-diazabicyclo
[2.2.2]octane (DABCO) in reuxing acetone to afford
CoFe2O4@SiO2–DABCO. Finally, CoFe2O4@SiO2–DABCO and
antimony trichloride was added in a round-bottomed ask
contained acetone under reux conditions to yield MNPs sup-
ported Sb catalyst ([CoFe2O4@SiO2–DABCO–Sb])19 (Scheme 2).
As determined by inductively coupled plasma mass spec-
trometry (ICP-MS), the content of antimony in the CoFe2O4@
SiO2–DABCO–Sb catalyst was 6.32 wt%, which provides direct
evidences for the fact that antimony was immobilized onto the
silica-coated magnetic nanoparticles. The EDS elemental anal-
ysis indicated the presence of Fe, Co, Si, Cl, O, C, N and Sb
(Fig. 1). Fig. 2 shows Fourier transform infrared (FT-IR) spec-
trum of CoFe2O4@SiO2 and CoFe2O4@SiO2–DABCO–Sb. The
presence of Co–O and Fe–O bonds in the magnetic particles was
Fig. 1 EDS spectrum of CoFe2O4@SiO2–DABCO–Sb.
Fig. 2 IR spectra of the (a) CoFe2O4@SiO2 and (b) CoFe2O4@SiO2–
DABCO–Sb.
bending modes respectively. The band that presents at near
2948 cmꢁ1 provides direct evidences to support the existence of
stretching of alkyl C–H. New peaks near 1474 cmꢁ1 is due to
CH2, and a characteristic broad absorbance at 1000–1200 cmꢁ1
shows the existence of C–N stretching, which clearly indicates
the presence of DABCO. As shown in Fig. 3, the SEM of the
magnetic CoFe2O4@SiO2–DABCO–Sb catalyst demonstrates
conrmed by the characteristic peak appeared at 597 cmꢁ1
,
which are the evidence to verify the presence of magnetic
nanoparticles. The obvious broad peak near 1200 cmꢁ1 is anti
symmetric Si–O–Si stretching. Two bands are present at 797 and
462 cmꢁ1 assignable to symmetric Si–O–Si stretching and
Scheme 2 Synthesis of CoFe2O4@SiO2–DABCO–Sb.
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Fig. 3 SEM image of CoFe2O4@SiO2–DABCO–Sb (a) “fresh” catalyst
and (b) “recovered” catalyst after the fifth run.
that the particles is spherical or quasi-spherical shape with a
mean particle diameter of 1.00 mm, which was also in a good
agreement with the results from TEM (Fig. 4). In addition, the
TEM image apparently shows the core–shell structure, giving
the indirect evidence to verify the formation of silica shell on
the surface of cobalt ferrite (Fig. 4b). The powder X-ray diffrac-
tion pattern of prepared catalyst CoFe2O4@SiO2–DABCO–Sb in
Fig. 5 was conrmed that the sample is typical CoFe2O4 crystals
phases. It displays diffraction peaks at around 18.4ꢀ, 30.1ꢀ,
35.6ꢀ, 43.3ꢀ, 57.3ꢀ and 62.6ꢀ corresponding to the (111), (220),
(311), (400), (511) and (440), which can be well indexed to the
cubic spinel phase of CoFe2O4 in accordance with literature
data (JCPDS 22-1086).
Fig. 4 TEM images of (a) CoFe2O4@SiO2–DABCO–Sb (b) a typically
core–shell structure of CoFe2O4@SiO2 NPs.
The activity of the immobilized antimony catalyst was
initially evaluated for the model reaction of (E)-(2-nitroprop-1-
en-1-yl)benzene (1 mmol), aniline (1 mmol) and acetylacetone
(1 mmol) in ethanol at 80 ꢀC. The reaction, as shown in Table 1,
proceeded very slowly in the absence of catalyst and only a trace
of desired product was found aer heating for more than 12 h
(Table 1, entry 1). Gratifyingly, CoFe2O4@SiO2–DABCO–Sb
exhibited very high activity, leading to the formation of 1-(2,5-
dimethyl-1,4-diphenyl-1H-pyrrol-3-yl)ethanone (4b) in 80%
Fig. 5 XRD pattern of CoFe2O4@SiO2–DABCO–Sb.
ꢀ
yield in ethanol at 80 C (Table 1, entry 17). Solvent screening
revealed a signicant solvent effect. When shiing the solvent
to water, THF, methanol, CH3CN or toluene, 4b was obtained in
ꢀ
ꢀ
30, 45, 40, 70, or 38% yield, respectively (Table 1, entries 7–11). Decreasing the reaction temperature from 80 C to 60 C, the
The EtOH–H2O (1 : 1) system was also examined for this reac- yield suffered an obvious decrease (52%, Table 1, entry 14).
tion, showing lower yield of the product (Table 1, entry 12). Lowering the catalyst loading to 0.5%, the yield decreased to
Among all these solvents, ethanol was found to be the best one 64%, whereas an increasing in catalyst concentration to 1 mol%
and afforded the highest yield. Furthermore, the reaction was did not produce better results.
investigated under solvent-free condition, the yield of product
Besides, the reactivities of different magnetical nano cata-
was not improved (Table 1, entry 13). Finally, reaction temper- lysts such as nano g-Fe2O3@SiO2–TfOH,15c g-Fe2O3@HAP–
ature and catalyst amount were further examined in ethanol. SO3H,15a g-Fe2O3@SiO2–NHC–Cu(II),11d g-Fe2O3@SiO2–NHC–
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Table 1 Reaction of (E)-(2-nitroprop-1-en-1-yl)benzene, aniline and acetylacetone in different conditionsa
Entry
Catalyst
Solvent
Temperature [ꢀC]
Yield [%]
1
2
3
4
5
6
7
8
No
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
H2O
THF
MeCN
MeOH
Toluene
EtOH–H2O (1 : 1)
Solvent-free
EtOH
EtOH
EtOH
EtOH
EtOH
80
80
80
80
80
80
80
80
Reux
Reux
80
80
80
60
80
80
80
Trace
46
48
57
60
40
30
45
40
70
38
36
78
52
64
75
80
80
82b
g-Fe2O3@SiO2–TfOH
g-Fe2O3@HAP–SO3H
g-Fe2O3@SiO2–NHC–Cu(II)
g-Fe2O3@SiO2–NHC–Zn(II)
CoFe2O4@SiO2
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb
CoFe2O4@SiO2–DABCO–Sb (0.1 mol%)
CoFe2O4@SiO2–DABCO–Sb (0.3 mol%)
CoFe2O4@SiO2–DABCO–Sb (0.5 mol%)
CoFe2O4@SiO2–DABCO–Sb (1 mol%)
CoFe2O4@SiO2–DABCO–Sb (0.5 mol%)
9
10
11
12
13
14
15
16
17
18
19
80
80
EtOH
a
Reaction condition: (E)-(2-nitroprop-1-en-1-yl)benzene (1 mmol), aniline (1 mmol) and acetylacetone (1 mmol), catalyst (0.5 mol%), solvent (1 ml),
b
12 h. 50 mmol scale.
Zn(II),11d and CoFe2O4@SiO2 were investigated. It was observed substrates with heteroaryl groups such as 2-furyl and 2-thienyl
that CoFe2O4@SiO2–DABCO–Sb served as the best catalyst to groups afforded 4i, 4j and 4n, 4o respectively in high yield.
provide 4b in optimum yield. Therefore, the optimal conditions Moreover, examination of nitroolen with a larger aromatic
were established as follows: use of 0.5 mol% CoFe2O4@SiO2– group, such as naphthyl, was also applied to this reaction to
DABCO–Sb as the catalyst and ethanol as the solvent to perform afford the desired product 4k, albeit in relatively lower yield.
the reaction at 80 ꢀC. To exploit the potential of the current
Next, we set out to test the reactivity of various substituted
catalytic system, the model reaction was scaled up to 50 mmol. amines. As depicted in Table 2, most of aniline with electron-
As expected, the desired product could be obtained in 82% yield donating or weakly electron-withdrawing substituents were
(Table 1, entry 19).
found to be applicable to this reaction and gave the expected
Having identied the optimized reaction conditions, the products in high to excellent yields. The nature of the substit-
scope and limitations of this three-component reaction were uent on the benzene ring of aniline had a slight impact on the
next explored by variation of substituents R and Ar of the yields. For example, for substrates with a methyl or methoxy
nitroolen component. Satisfactorily as shown in Table 2, when group attached on the benzene ring, the corresponding prod-
R is hydrogen in nitroolens, the reaction was completed in 0.25 ucts were obtained in yields of 82% and 88%, respectively (Table
h to afford 4a in 93% yield (Table 2, entry 1). The alkyl group of 2, entries 19 and 20). Aniline with strongly electron-withdrawing
nitroolens exhibited an inuence for this three-component group such as triuoromethyl decreased the reactivity and gave
reaction. The reaction with methyl-substituted nitroolens was lower but still acceptable yield. However, the target product
slower, but high yield of product was also maintained (Table 2, could not be obtained when a strong electron-withdrawing
entry 2). Early experiments using the conditions reported by group such as nitro was present. Moreover, amines containing
Silveira showed that CeCl3$7H2O promoted this reaction to give heteroaromatic groups such as furan-2-ylmethanamine also
4b in only 45% yield.20 Nitroolens with ethyl group smoothly underwent the reaction, affording the desired products 4ab and
produced the corresponding products 4l–4n, although longer 4as in high yield. Also, 9H-uoren-2-amine was well tolerated to
reaction times were required as the steric hindrance of R give 4r and 4ac in good yield. Additionally, different kinds of
increased. Aryl groups with electron-rich or electron-poor aliphatic amines gave the desired products in excellent yield.
substituents in nitroolens revealed little impact on the reaction
To further explore the substrate scope, we then extended the
times and the yields of the products. Furthermore, the scope of this reaction to several b-ketoesters such as methyl
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Table 2 Synthesis of functionalized pyrroles 4
Entry
1
Nitroolen
Amine
PhNH2
R2
R3
Product
Time (h)
0.25
Yielda (%)
mp (ꢀC)
Me
Me
4a
93
80
106–107
2
3
4
PhNH2
PhNH2
PhNH2
Me
Me
Me
Me
Me
Me
4b
4c
4d
12
12
14
102–103
Oil
87
86
75
127–128
5
6
PhNH2
PhNH2
Me
Me
Me
Me
4e
4f
16
16
Oil
78
108–110
7
8
PhNH2
PhNH2
Me
Me
Me
Me
4g
4h
14
16
85
75
146–147
Oil
9
PhNH2
PhNH2
Me
Me
Me
Me
4i
4j
15
15
88
82
101–102
81–82
10
11
PhNH2
Me
Me
4k
12
47
133–134
12
13
14
PhNH2
PhNH2
PhNH2
Me
Me
Me
Me
Me
Me
4l
20
20
20
80
80
76
Oil
Oil
Oil
4m
4n
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Table 2 (Contd.)
Entry
15
Nitroolen
Amine
PhNH2
R2
R3
Product
Time (h)
20
Yielda (%)
mp (ꢀC)
Oil
Me
Me
4o
78
92
16
17
4-CMe3C6H4NH2
Me
Me
Me
Me
4p
4q
0.5
1
146–148
142–143
75
18
19
20
21
22
23
24
25
26
27
28
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
Me
4r
1
12
12
14
15
16
16
15
16
14
6
80
82
88
82
75
70
72
77
51
85
90
148–149
112–113
130–132
95–96
Oil
4-CH3C6H4NH2
4-OCH3C6H4NH2
4-FC6H4NH2
4s
4t
4u
4v
4-ClC6H4NH2
2-BrC6H4NH2
3-BrC6H4NH2
4-BrC6H4NH2
4-CF3C6H4NH2
4-OCF3C6H4NH2
4w
4x
Oil
Oil
4y
106–107
Oil
4z
4aa
4ab
125–126
120–121
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Table 2 (Contd.)
Entry
29
Nitroolen
Amine
R2
R3
Product
Time (h)
14
Yielda (%)
mp (ꢀC)
Me
Me
4ac
73
91
90
92
153–155
30
31
32
H2C]CHCH2NH2
PhCH2NH2
Me
Me
Me
Me
Me
Me
4ad
4ae
4af
6
6
6
Oil
Oil
PhCH2CH2NH2
124–125
33
Me
Me
4ag
6
87
92–93
34
35
36
37
38
39
40
41
42
43
Me
Me
Me
Me
Me
Me
Me
Me
Et
Me
4ah
4ai
6
12
6
89
72
88
86
82
85
80
78
76
83
Oil
Me
61–62
Oil
Me
4aj
Me
4ak
4al
6
Oil
PhNH2
PhNH2
PhNH2
PhNH2
PhNH2
PhNH2
OMe
8
108–109
83–84
72–73
Oil
OEt
4am
4an
4ao
4ap
4aq
8
OCH2CH2OMe
OCH2CH]CH2
OMe
8
10
10
8
100–101
96–97
Me
OCMe3
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Table 2 (Contd.)
Entry
44
Nitroolen
Amine
PhNH2
R2
R3
Product
Time (h)
8
Yielda (%)
mp (ꢀC)
Me
OCH2CH(CH3)2
4ar
81
89
86
82
70–71
45
46
47
Me
Me
Me
Me
Me
Me
4as
4at
4au
12
12
12
103–104
Oil
PhCH2NH2
Oil
48
Me
Me
4av
12
83
Oil
a
Isolated yield.
acetoacetate, ethyl acetoacetate, 2-methoxyethyl acetoacetate,
The magnetic CoFe2O4@SiO2–DABCO–Sb catalyst exhibited
allyl acetoacetate, tert-butyl-3-oxobutanoate, isobutyl-3-oxobu- high reactivity in the reaction of synthesis of multisubstituted
tanoate and methyl-3-oxopentanoate. In general, b-ketoesters pyrroles owing to its high dispersion in EtOH and easy accessi-
were also found to be suitable reaction partners in this reaction bility to the active sites. Upon completion of the reaction, the
and gave the desired products in high yields (Table 2, entries catalyst can be easily removed using an external magnetic from
38–44). Thus, these successful results greatly proved that this the reaction mixture, avoiding a ltration step. The recover
procedure was extendable to various substrates in three- catalyst was washed with ethyl acetate, air-dried and then reused
component reactions, generating moderate to high yields of the directly in model reaction for the next round without further
functionalized pyrroles.
purication. The results showed that the catalyst can be recycled
The structures of the prepared products were identied from for up to ve times with essentially no loss of catalytic activity,
their IR, 1H NMR, 13C NMR spectra and elemental analysis. The which indicates that the prepared catalyst possessed excellent
structure of the corresponding product 4o has also been eluci- activity and reusability (Table 3). Furthermore, the SEM image of
dated by single-crystal X-ray crystallographic analysis (Fig. 6).
recovered catalysts aer h cycle does not show any signicant
change in the shape and size of the magnetic nanoparticles,
which provides hard evidence to demonstrate that MNPs-sup-
ported Sb catalyst was high chemical stable (Fig. 3).
Table 3 Recycling of the catalyst
Entry
Recycle
Yielda (%)
1
2
3
4
5
1st
80
80
78
78
76
2nd
3rd
4th
5th
Fig.
964609).
6 Single-crystal X-ray structural of compound 4o (CCDC
a
Isolated yield.
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double-distilled water and anhydrous ethanol, and dried at
100 C for 5 h to give the 3-chloropropyl CoFe2O4@SiO2.
Conclusions
ꢀ
For the preparation of CoFe2O4@SiO2–DABCO: 3-chlor-
opropyl CoFe2O4@SiO2 (0.5 g) and DABCO (0.56 g, 5 mmol) were
added in a 50 ml round-bottomed ask contained dry acetone
(30 ml) and reuxed for 36 h. The solid was collected using a
permanent magnet, followed by washing with acetone, ethanol,
and methanol in turn. Finally, the obtained CoFe2O4@SiO2–
In summary, a new type of magnetically separable and easily
recyclable heterogeneous Sb catalyst have been successfully
prepared by immobilizing Sb onto DABCO-modied MNPs,
which has demonstrated a promising catalytic activity for the
one-pot three-component coupling reaction of amines, nitro-
olen and 1,3-dicarbonyl compounds. This environmentally
friendly, atom-economical and efficient methodology allows
preparation of various multisubstituted pyrroles with good to
excellent yields starting from readily available materials under
mild conditions. This magnetic nanoparticle CoFe2O4 supported
Sb catalyst can easily be separated and recovered from the reac-
tion mixture by decantation using an external magnet. And no
signicant loss of activity occurred aer ve consecutive cycles,
indicating great potential in large-scale industrial processes.
ꢀ
DABCO was dried under vacuum at 60 C for 24 h.
The obtained CoFe2O4@SiO2–DABCO (0.25 g) were added to
the solution of antimony(III) chloride (0.225 g) in dry acetone
(10 ml) in a 25 ml round-bottomed ask equipped with a reux
condenser, and reuxed for 12 h. The resulting solid was
collected using a permanent magnet, followed by washing three
times with acetone and dried under vacuum at 50 ꢀC for 12 h to
give CoFe2O4@SiO2–DABCO–Sb as a black powder.
Experimental section
General procedure for synthesis of functionalized pyrroles 4
To a mixture of amines (1 mmol), nitroolen (1 mmol) and 1,3-
dicarbonyl compound (1 mmol) in EtOH (1 ml), CoFe2O4@
SiO2–DABCO–Sb (0.5 mol%) was added. The reaction mixture
was stirred at 80 ꢀC (monitored by TLC). Aer completion of the
reaction, the reaction mixture was cooled to room temperature
and the catalyst was separated magnetically, washed with ethyl
acetate, and used for subsequent cycles aer drying under
vacuum. The crude products were obtained by evaporation of
the solvent and puried by column chromatography on silica
gel using ethyl acetate/hexane as the eluent.
All solvents and chemicals were obtained commercially and were
used as received. IR spectra were recorded using KBr pellets or as
liquid lms on KBr pellets with a Bruker-TENSOR 27 spec-
trometer. X-ray diffraction analysis was carried out using a
PANalytical X'Pert Pro X-ray diffractometer. Surface morphology
and particle size were studied using a Hitachi S-4800 SEM
instrument. Transmission electron microscope (TEM) observa-
tion was performed using Hitachi H-7650 microscope at 80 kV.
Elemental compositions were determined with a Hitachi S-4800
scanning electron microscope equipped with an INCA 350
energy dispersive spectrometer (SEM-EDS) presenting a 133 eV
resolution at 5.9 keV. The ICP-MS analyses were carried out with
an X Series 2 spectrometer. Melting points were measured on an
X-4 digital melting point apparatus are uncorrected. NMR
spectra were recorded with a Bruker DRX-500 spectrometer at
500 MHz for 1H NMR and 125 MHz for 13C NMR using CDCl3 as
the solvent and TMS as an internal standard. Elemental analyses
were performed on a Vario EL III CHNOS elemental analyzer.
1-(2-Methyl-1,4-diphenyl-1H-pyrrol-3-yl)ethanone
(4a).
White solid, 106–107 ꢀC; IR (KBr): 3037, 2928, 1657, 1498, 1412,
1228, 752, 700 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 2.08 (s, 3H),
2.41 (s, 3H), 6.67 (s, 1H), 7.30–7.34 (m, 3H), 7.38–7.39 (m, 4H),
7.42 (t, J ¼ 7.5 Hz, 1H), 7.49 (t, J ¼ 7.0 Hz, 2H); 13C NMR (CDCl3,
125 MHz) d 12.9, 31.1, 120.6, 122.6, 126.2, 126.3, 126.8, 128.1,
128.3, 129.3, 129.3, 135.3, 136.0, 138.7, 197.6 ppm. Anal. calcd
for C19H17NO: C, 82.88; H, 6.22; N, 5.09. Found: C, 82.72; H,
6.04; N, 4.95; ESI-MS: m/z ¼ 276 (M + 1)+.
1-(2,5-Dimethyl-1,4-diphenyl-1H-pyrrol-3-yl)ethanone (4b).
Preparation of CoFe2O4@SiO2–DABCO–Sb magnetic
nanoparticles
ꢀ
White solid, mp 102–103 C; IR (KBr): 2920, 1641, 1496, 1383,
1165, 952, 704 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 1.85 (s, 3H),
CoFe2O4 NPs were prepared by a chemical co-precipitation 1.93 (s, 3H), 2.28 (s, 3H), 7.25–7.32 (m, 5H), 7.40 (t, J ¼ 7.5 Hz,
technique using FeCl3$6H2O and CoCl2$6H2O as precursors 2H), 7.46 (t, J ¼ 7.0 Hz, 1H), 7.51 (t, J ¼ 7.5 Hz, 2H) ppm; 13C
according to our previously reported procedure.15d Coating of a NMR (CDCl3, 125 MHz) d 11.1, 13.0, 31.0, 121.8, 122.1, 126.6,
layer of silica on the surface of the CoFe2O4 NPs was prepared 126.7, 128.1, 128.2, 128.6, 129.4, 130.5, 134.9, 136.9, 137.6, 197.3
according to the procedure of Chen et al.17 The CoFe2O4 NPs ppm; anal. calcd for C20H19NO: C, 83.01; H, 6.62; N, 4.84; found:
(0.5 g) were dispersed in a 1 L solution with the molar compo- C, 82.92; H, 6.47; N, 4.71; ESI-MS: m/z ¼ 290 (M + 1)+.
sition of 292NH4OH : 1 CTABr : 2773H2O under vigorous mix-
1-(2,5-Dimethyl-1-phenyl-4-(p-tolyl)-1H-pyrrol-3-yl)ethanone
ing. Tetraethyl orthosilicate was then added successively. Aer (4c). Yellow sticky liquid; IR (KBr): 2920, 1653, 1518, 1458, 1383,
stirring for 24 h at room temperature, the black CoFe2O4 NPs 1165, 950, 700 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 1.84 (s, 3H),
were collected with a permanent magnet, followed by washing 1.95 (s, 3H), 2.28 (s, 3H), 2.39 (s, 3H), 7.18–7.21 (m, 4H), 7.25
three times with ethanol, diethyl ether and drying at 100 ꢀC in a (d, J ¼ 7.5 Hz, 2H), 7.45 (t, J ¼ 7.5 Hz, 1H), 7.50 (t, J ¼ 7.5 Hz, 2H)
vacuum for 24 h. The obtained CoFe2O4@SiO2 (0.5 g) was added ppm; 13C NMR (CDCl3, 125 MHz) d 11.2, 13.0, 21.2, 31.0, 121.8,
to the solution of 3-chloropropyltrimethoxysilane (5 mmol) and 122.0, 126.6, 128.2, 128.6, 128.9, 130.3, 133.8, 134.8, 136.1,
triethylamine (0.25 ml) in dry toluene (20 ml) and reuxed for 48 137.6, 197.5 ppm; anal. calcd for C21H21NO: C, 83.13; H, 6.98;
h. Aer the reaction nished, the 3-chloropropyl CoFe2O4@SiO2 N, 4.62; found: C, 83.02; H, 6.79; N, 4.58; ESI-MS: m/z ¼ 304
NPs were separated by a permanent magnet, washed with (M + 1)+.
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1-(4-(4-Fluorophenyl)-2,5-dimethyl-1-phenyl-1H-pyrrol-3-yl)-
1-(2,5-Dimethyl-1-phenyl-4-(thiophen-2-yl)-1H-pyrrol-3-yl)-
ꢀ
ethanone (4d). Yellow solid, mp 127–128 ꢀC; IR (KBr): 2922, 1649, ethanone (4j). Yellow solid, mp 81–82 C; IR (KBr): 2918, 1647,
1514, 1415, 1383, 1215, 954, 698 cmꢁ1; 1H NMR (CDCl3, 500 MHz) 1498, 1383, 1261, 1076, 945, 698 cmꢁ1 1H NMR (CDCl3, 500
;
d 1.82 (s, 3H), 1.94 (s, 3H), 2.28 (s, 3H), 7.09 (t, J ¼ 8.5 Hz, 2H), MHz) d 1.88 (s, 3H), 2.05 (s, 3H), 2.27 (s, 3H), 6.94 (dd, J ¼ 1.0,
7.24–7.28 (m, 4H), 7.47 (t, J ¼ 7.0 Hz, 1H), 7.52 (t, J ¼ 8.0 Hz, 2H) 3.5 Hz, 1H), 7.07 (dd, J ¼ 3.5, 5.0 Hz, 1H), 7.23 (d, J ¼ 7.0 Hz,
ppm; 13C NMR (CDCl3, 125 MHz) d 11.0, 13.0, 31.0, 115.1 (d, 2JCF
21.2 Hz), 120.9, 121.7, 126.8, 128.1, 128.7, 129.5, 131.9 (d, 3JCF
¼
¼
2H), 7.33 (dd, J ¼ 1, 5.0 Hz, 1H), 7.45–7.52 (m, 3H) ppm; 13C
NMR (CDCl3, 125 MHz) d 11.2, 13.1, 30.3, 113.5, 122.3, 125.8,
7.5 Hz), 132.8 (d, 4JCF ¼ 3.2 Hz), 135.0, 137.5, 161.8 (d, 1JCF ¼ 244.1 127.1, 127.9, 128.1, 128.8, 128.9, 129.5, 135.3, 137.3, 137.6, 196.8
Hz), 196.9 ppm; anal. calcd for C20H18FNO: C, 78.15; H, 5.90; N, ppm; anal. calcd for C18H17NOS: C, 73.19; H, 5.80; N, 4.74;
4.56; found: C, 78.01; H, 5.76; N, 4.45; ESI-MS: m/z ¼ 308 (M + 1)+. found: C, 73.02; H, 5.65; N, 4.59; ESI-MS: m/z ¼ 296 (M + 1)+.
1-(4-(2-Chlorophenyl)-2,5-dimethyl-1-phenyl-1H-pyrrol-3-yl)-
1-(2,5-Dimethyl-4-(naphthalen-1-yl)-1-phenyl-1H-pyrrol-3-yl)-
ethanone (4e). Yellow sticky liquid; IR (KBr): 2920, 1647, 1516, ethanone (4k). Yellow solid, mp 133–134 ꢀC; IR (KBr): 2918,
1
1406, 1384, 1168, 950, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d 1647, 1498, 1383, 1276, 949, 702 cmꢁ1
;
1H NMR (CDCl3, 500
1.76 (s, 3H), 1.91 (s, 3H), 2.32 (s, 3H), 7.24–7.34 (m, 5H), 7.45– MHz) d 1.63 (s, 3H), 1.71 (s, 3H), 2.39 (s, 3H), 7.32 (d, J ¼ 7.5 Hz,
7.49 (m, 2H), 7.51 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR (CDCl3, 125 2H), 7.43–7.55 (m, 7H), 7.82 (d, J ¼ 8.5 Hz, 1H), 7.85 (d, J ¼ 8.5
MHz) d 11.1, 13.3, 30.1, 119.0, 121.3, 126.6, 127.2, 128.1, 128.3, Hz, 1H), 7.89 (d, J ¼ 8.0 Hz, 1H) ppm; 13C NMR (CDCl3, 125
128.6, 128.7, 129.5, 132.8, 135.0, 135.3, 136.0, 137.4, 196.2 ppm; MHz) d 11.2, 13.4, 30.1, 119.5, 122.3, 125.5, 125.8, 126.2, 126.3,
anal. calcd for C20H18ClNO: C, 74.18; H, 5.60; N, 4.33; found: C, 127.5, 128.2, 128.3, 128.6, 128.7, 129.1, 129.5, 133.6, 133.7,
74.09; H, 5.47; N, 4.19; ESI-MS: m/z ¼ 324 (M + 1)+.
134.8, 135.6, 137.6, 196.9 ppm; anal. calcd for C24H21NO: C,
1-(4-(3-Chlorophenyl)-2,5-dimethyl-1-phenyl-1H-pyrrol-3-yl)- 84.92; H, 6.24; N, 4.13; found: C, 84.81; H, 6.19; N, 4.02; ESI-MS:
ethanone (4f). Yellow solid, mp 108–110 ꢀC; IR (KBr): 2920, m/z ¼ 340 (M + 1)+.
1
1647, 1595, 1516, 1383, 1168, 952, 696 cmꢁ1; H NMR (CDCl3,
1-(5-Ethyl-2-methyl-1,4-diphenyl-1H-pyrrol-3-yl)ethanone (4l).
500 MHz) d 1.84 (s, 3H), 1.97 (s, 3H), 2.27 (s, 3H), 7.19 (d, J ¼ 7.5 Yellow sticky liquid; IR (KBr): 2929, 1653, 1496, 1253, 1166, 1028,
Hz, 1H), 7.23–7.34 (m, 5H), 7.47 (t, J ¼ 7.0 Hz, 1H), 7.52 (t, J ¼ 7.5 700 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 0.71 (t, J ¼ 7.5 Hz, 3H),
Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.1, 13.0, 31.0, 1.89 (s, 3H), 2.26 (s, 3H), 2.27 (q, J ¼ 7.5 Hz, 2H), 7.28–7.33 (m,
120.7, 121.7, 126.7, 127.0, 128.1, 128.7, 128.8, 129.4, 129.5, 5H), 7.39 (t, J ¼ 8.0 Hz, 2H), 7.46–7.53 (m, 3H) ppm; 13C NMR
130.4, 134.0, 135.2, 137.3, 138.9, 196.7 ppm; anal. calcd for (CDCl3, 125 MHz) d 12.9, 14.9, 17.9, 31.0, 121.7, 121.9, 126.7,
C
20H18ClNO: C, 74.18; H, 5.60; N, 4.33; found: C, 74.08; H, 5.44; 128.2, 128.5, 128.7, 129.3, 130.6, 132.9, 135.1, 137.0, 137.6, 197.2
N, 4.25; ESI-MS: m/z ¼ 324 (M + 1)+.
ppm; anal. calcd for C21H21NO: C, 83.13; H, 6.98; N, 4.62; found:
1-(4-(4-Chlorophenyl)-2,5-dimethyl-1-phenyl-1H-pyrrol-3-yl)- C, 82.99; H, 6.79; N, 4.55; ESI-MS: m/z ¼ 304 (M + 1)+.
ethanone (4g). Yellow solid, mp 146–147 ꢀC; IR (KBr): 2914, 1647,
1-(5-Ethyl-2-methyl-1-phenyl-4-(p-tolyl)-1H-pyrrol-3-yl)ethanone
1489, 1383, 1166, 1087, 952, 698 cmꢁ1; 1H NMR (CDCl3, 500 MHz) (4m). Yellow sticky liquid; IR (KBr): 2929, 1653, 1498, 1363, 1165,
d 1.85 (s, 3H), 1.98 (s, 3H), 2.30 (s, 3H), 7.26–7.28 (m, 4H), 7.40 (d, 950, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.71 (t, J ¼ 7.5 Hz,
1
J ¼ 8.0 Hz, 2H), 7.49 (t, J ¼ 7.0 Hz, 1H), 7.54 (t, J ¼ 7.5 Hz, 2H) 3H), 1.91 (s, 3H), 2.26 (s, 3H), 2.27 (q, J ¼ 7.5 Hz, 2H), 2.39 (s, 3H),
ppm; 13C NMR (CDCl3, 125 MHz) d 11.1, 13.0, 31.1, 120.8, 121.7, 7.18–7.22 (m, 4H), 7.27–7.29 (m, 2H), 7.45–7.52 (m, 3H) ppm; 13
C
126.9, 128.1, 128.4, 128.7, 129.5, 131.7, 132.5, 135.1, 135.4, 137.4, NMR (CDCl3, 125 MHz) d 12.9, 14.9, 18.0, 21.2, 31.0, 121.7, 121.8,
196.8 ppm; anal. calcd for C20H18ClNO: C, 74.18; H, 5.60; N, 4.33; 128.5, 128.6, 128.9, 129.3, 130.4, 132.9, 133.9, 135.0, 136.2, 137.6,
found: C, 74.06; H, 5.48; N, 4.25; ESI-MS: m/z ¼ 324 (M + 1)+.
197.3 ppm; anal. calcd for C22H23NO: C, 83.24; H, 7.30; N, 4.41;
1-(2,5-Dimethyl-4-(4-nitrophenyl)-1-phenyl-1H-pyrrol-3-yl)- found: C, 82.90; H, 7.28; N, 4.27; ESI-MS: m/z ¼ 318 (M + 1)+.
ethanone (4h). Yellow sticky liquid; IR (KBr): 2922, 1647, 1527,
1-(5-Ethyl-4-(furan-2-yl)-2-methyl-1-phenyl-1H-pyrrol-3-yl)-
1
1348, 1174, 954, 690 cmꢁ1; H NMR (CDCl3, 500 MHz) d 1.86 ethanone (4n). Yellow sticky liquid; IR (KBr): 2931, 1647, 1508,
(s, 3H), 2.01 (s, 3H), 2.29 (s, 3H), 7.25 (d, J ¼ 7.0 Hz, 2H), 7.49– 1432, 1151, 1010, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.82
1
7.58 (m, 4H), 7.64 (d, J ¼ 7.5 Hz, 1H), 8.18 (d, J ¼ 7.5 Hz, 2H) (t, J ¼ 7.5 Hz, 3H), 2.03 (s, 3H), 2.24 (s, 3H), 3.35 (q, J ¼ 7.5 Hz,
ppm; 13C NMR (CDCl3, 125 MHz) d 11.1, 13.2, 31.1, 119.8, 121.5, 2H), 6.33 (d, J ¼ 3.0 Hz, 1H), 6.47–6.48 (m, 1H), 7.23–7.25
121.6, 125.0, 127.6, 128.1, 129.0, 129.6, 135.6, 136.7, 137.2, 138.8, (m, 2H), 7.46–7.53 (m, 4H) ppm; 13C NMR (CDCl3, 125 MHz) d
195.9 ppm; anal. calcd for C20H18N2O3: C, 71.84; H, 5.43; N, 8.38; 12.8, 15.0, 18.3, 29.4, 109.2, 110.8, 110.9, 121.1, 128.3, 128.9,
found: C, 71.76; H, 5.32; N, 8.25; ESI-MS: m/z ¼ 335 (M + 1)+.
1-(4-(Furan-2-yl)-2,5-dimethyl-1-phenyl-1H-pyrrol-3-yl)ethanone
129.4, 135.8, 137.1, 141.9, 148.8, 196.5 ppm; anal. calcd for
19H19NO2: C, 77.79; H, 6.53; N, 4.77; found: C, 77.62; H, 6.42;
C
(4i). White solid, mp 101–102 ꢀC; IR (KBr): 2922, 1643, 1516, 1383, N, 4.59; ESI-MS: m/z ¼ 194 (M + 1)+.
1172, 1076, 954, 705 cmꢁ1
;
1H NMR (CDCl3, 500 MHz) d 1.93
1-(5-Ethyl-2-methyl-1-phenyl-4-(thiophen-2-yl)-1H-pyrrol-3-yl)-
(s, 3H), 2.05 (s, 3H), 2.27 (s, 3H), 6.32 (d, J ¼ 3.0 Hz, 1H), 6.48 ethanone (4o). Yellow sticky liquid; IR (KBr): 2931, 1647, 1558,
1
(s, 1H), 7.21 (d, J ¼ 7.0 Hz, 2H), 7.45–7.52 (m, 4H) ppm; 13C NMR 1508, 1288, 1074, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.78
(CDCl3, 125 MHz) d 11.3, 12.9, 29.4, 109.1, 111.0, 111.4, 121.1, (t, J ¼ 7.5 Hz, 3H), 2.03 (s, 3H), 2.25 (s, 3H), 2.32 (q, J ¼ 7.5 Hz,
128.0, 128.8, 129.4, 129.5, 135.7, 137.2, 141.9, 148.9, 196.5 ppm; 2H), 6.96 (dd, J ¼ 1.5, 3.5 Hz, 1H), 7.08 (dd, J ¼ 3.5, 5.5 Hz, 1H),
anal. calcd for C18H17NO2: C, 77.40; H, 6.13; N, 5.01; found: C, 7.26–7.27 (m, 2H), 7.34 (dd, J ¼ 1.5, 5.5 Hz, 1H), 7.46–7.53 (m, 3H)
77.28; H, 6.07; N, 4.85; ESI-MS: m/z ¼ 280 (M + 1)+.
12938 | RSC Adv., 2014, 4, 12929–12943
ppm; 13C NMR (CDCl3, 125 MHz) d 12.9, 15.1, 18.2, 30.2, 112.9,
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122.2, 125.8, 127.0, 128.1, 128.4, 128.8, 129.4, 135.1, 135.5, 137.3, 7.33 (m, 3H), 7.39 (t, J ¼ 7.0 Hz, 2H) ppm; 13C NMR (CDCl3, 125
2
137.5, 196.9 ppm; anal. calcd for C19H19NOS: C, 73.75; H, 6.19; N, MHz) d 11.1, 12.9, 30.9, 116.3 (d, JCF ¼ 22.7 Hz), 121.9, 122.2,
4.53; found: C, 73.59; H, 6.00; N, 4.51; ESI-MS: m/z ¼ 310 (M + 1)+. 126.7, 128.2, 129.9 (d, 3JCF ¼ 8.7 Hz), 130.4, 133.5 (d, 4JCF ¼ 3.3
1
1-(1-(5-(tert-Butyl)phenyl)-2-methyl-5-phenyl-1H-pyrrol-3-yl)- Hz), 134.9, 136.7, 162.3 (d, JCF ¼ 247.5 Hz), 197.4 ppm; anal.
ꢀ
ethanone (4p). White solid, 146–148 C; IR (KBr): 2929, 1650, calcd for C20H18FNO: C, 78.15; H, 5.90; N, 4.56; found: C, 78.06;
1512, 1408, 1220, 843, 756, 702 cmꢁ1; 1H NMR (CDCl3, 500 MHz) H, 5.81; N, 4.49; ESI-MS: m/z ¼ 308 (M + 1)+.
d 1.37 (s, 9H), 2.07 (s, 3H), 2.41 (s, 3H), 6.65 (s, 1H), 7.25 (d, J ¼
1-(1-(4-Chlorophenyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)-
8.5 Hz, 2H), 7.30–7.32 (m, 1H), 7.37–7.38 (m, 4H), 7.58 (d, J ¼ 8.5 ethanone (4v). Yellow sticky liquid; IR (KBr): 2920, 1647, 1496,
Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 12.9, 31.1, 31.3, 34.7, 1384, 1166, 952, 690 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 1.85 (s,
120.7, 122.4, 125.7, 126.1, 126.2, 126.7, 128.2, 129.3, 135.4, 3H), 1.92 (s, 3H), 2.28 (s, 3H), 7.21 (d, J ¼ 8.5 Hz, 2H), 7.28–7.32
136.1, 136.1, 151.2, 197.6 ppm; anal. calcd for C23H25NO: C, (m, 3H), 7.39 (t, J ¼ 7.0 Hz, 1H), 7.48 (d, J ¼ 8.5 Hz, 2H) ppm; 13
C
83.34; H, 7.60; N, 4.23; found: C, 83.28; H, 7.56; N, 4.15; ESI-MS: NMR (CDCl3, 125 MHz) d 11.1, 13.0, 30.9, 122.1, 122.4, 126.5,
m/z ¼ 332 (M + 1)+.
126.7, 128.2, 129.5, 129.7, 130.4, 134.6, 134.7, 136.1, 136.6, 197.3
1-(2-Methyl-1-(naphthalen-1-yl)-4-phenyl-1H-pyrrol-3-yl)etha- ppm; anal. calcd for C20H18ClNO: C, 74.18; H, 5.60; N, 4.33;
none (4q). White solid, 142–143 ꢀC; IR: 3130, 2929, 1657, 1506, found: C, 74.05; H, 5.48; N, 4.26; ESI-MS: m/z ¼ 324 (M + 1)+.
1
1438, 1257, 1234, 1128, 806, 777; H NMR (CDCl3, 500 MHz) d
1-(1-(2-Bromophenyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)-
2.15 (s, 3H), 2.22 (s, 3H), 6.71 (s, 1H), 7.32 (t, J ¼ 7.5 Hz, ethanone (4w). Yellow sticky liquid; IR (KBr): 2918, 1508, 1481,
1
1H),7.38–7.48 (m, 6H), 7.50–7.53 (m, 1H), 7.57 (t, J ¼ 7.5 Hz, 2H), 1383, 1273, 1166, 952, 706 cmꢁ1; H NMR (CDCl3, 500 MHz) d
7.96 (t, J ¼ 9.0 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 12.4, 1.79 (s, 3H), 1.94 (s, 3H), 2.23 (s, 3H), 7.29–7.41 (m, 7H), 7.47 (t, J
31.2, 121.7, 121.8, 122.9, 125.2, 125.3, 126.1, 126.8, 126.9, 127.6, ¼ 7.5 Hz, 1H), 7.76 (d, J ¼ 8.0 Hz, 1H) ppm; 13C NMR (CDCl3,
128.2, 128.3, 129.3, 129.4, 130.6, 134.1, 135.3, 136.1, 137.0, 197.7 125 MHz) d 10.6, 12.6, 31.0, 121.7, 122.2, 123.8, 126.3, 126.6,
ppm; anal. calcd for C23H19NO: C, 84.89; H, 5.89; N, 4.30; found: 128.1, 128.5, 130.3, 130.5, 130.6, 133.6, 134.8, 136.8, 137.2, 197.3
C, 84.79; H, 5.81; N, 4.15; ESI-MS: m/z ¼ 326 (M + 1)+.
ppm; anal. calcd for C20H18BrNO: C, 65.23; H, 4.93; N, 3.80;
1-(1-(9H-Fluoren-2-yl)-2-methyl-4-phenyl-1H-pyrrol-3-yl)etha- found: C, 62.20; H, 4.87; N, 3.69; ESI-MS: m/z ¼ 368 (M + 1)+.
ꢀ
none (4r). White solid, 148–149 C; IR (KBr): 3035, 2920, 1657,
1-(1-(3-Bromophenyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)-
1
1512, 1404, 772, 732 cmꢁ1; H NMR (CDCl3, 500 MHz) d 2.09 ethanone hydrobromide (4x). Yellow sticky liquid; IR (KBr):
(s, 3H), 2.45 (s, 3H), 3.98 (s, 2H), 6.72 (s, 1H), 7.31–7.43 (m, 8H), 2920, 1647, 1508, 1479, 1383, 1273, 1166, 952, 698 cmꢁ1 1H
;
7.50 (s, 1H), 7.58 (d, J ¼ 7.5 Hz, 1H), 7.82 (d, J ¼ 7.5 Hz, 1H), 7.86 NMR (CDCl3, 500 MHz) d 1.86 (s, 3H), 1.92 (s, 3H), 2.29 (s, 3H),
(d, J ¼ 7.5 Hz, 1H) ppm; 13C NMR (CDCl3, 125 MHz) d 13.1, 31.2, 7.22 (d, J ¼ 8.0 Hz, 1H), 7.28–7.33 (m, 3H), 7.40 (t, J ¼ 8.0 Hz,
36.9, 120.2, 120.3, 120.8, 122.5, 123.0, 125.0, 125.2, 126.3, 126.8, 3H), 7.45 (s, 1H), 7.61 (d, J ¼ 8.0 Hz, 1H) ppm; 13C NMR (CDCl3,
127.1, 127.3, 128.3, 129.4, 135.5, 136.1, 137.2, 140.5, 141.7, 125 MHz) d 11.2, 13.0, 31.0, 122.1, 122.4, 122.8, 126.5, 126.7,
143.4, 145.3, 197.6 ppm; anal. calcd for C26H21NO: C, 85.92; H, 127.0, 128.3, 130.4, 130.7, 131.4, 131.9, 134.7, 136.6, 138.9, 197.3
5.82; N, 3.85; found: C, 85.86; H, 5.69; N, 3.78; ESI-MS: m/z ¼ 364 ppm; anal. calcd for C20H18BrNO: C, 65.23; H, 4.93; N, 3.80;
(M + 1)+.
found: C, 65.04; H, 4.81; N, 3.69; ESI-MS: m/z ¼ 368 (M + 1)+.
1-(1-(4-Bromophenyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)-
1-(2,5-Dimethyl-4-phenyl-1-(p-tolyl)-1H-pyrrol-3-yl)ethanone
(4s). Yellow solid, mp 112–113 C; IR (KBr): 2920, 1647, 1508, ethanone (4y). Yellow solid, mp 106–107 ꢀC; IR (KBr): 2922,
ꢀ
1383, 1166, 950, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d 1.84 1658, 1519, 1489, 1384, 1263, 1168, 952, 705 cmꢁ1
;
1H NMR
1
(s, 3H), 1.93 (s, 3H), 2.28 (s, 3H), 2.43 (s, 3H), 7.13 (d, J ¼ 8.0 Hz, (CDCl3, 500 MHz) d 1.85 (s, 3H), 1.92 (s, 3H), 2.28 (s, 3H), 7.15
2H), 7.29–7.31 (m, 5H), 7.39 (t, J ¼ 7.5 Hz, 2H), ppm; 13C NMR (d, J ¼ 8.5 Hz, 2H), 7.28–7.33 (m, 3H), 7.39 (t, J ¼ 7.5 Hz, 2H),
(CDCl3, 125 MHz) d 10.9, 12.8, 20.9, 30.7, 121.4, 121.7, 126.3, 7.65 (d, J ¼ 8.5 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.1,
126.5, 127.6, 127.9, 129.8, 130.2, 134.6, 134.8, 136.7, 138.3, 197.0 13.0, 31.0, 122.1, 122.4, 122.7, 126.5, 126.7, 128.2, 129.8, 130.4,
ppm; anal. calcd for C21H21NO: C, 83.13; H, 6.98; N, 4.62; found: 132.7, 134.7, 136.6, 197.4 ppm; anal. calcd for C20H18BrNO: C,
C, 83.1; H, 6.79; N, 4.52; ESI-MS: m/z ¼ 304 (M + 1)+.
65.23; H, 4.93; N, 3.80; found: C, 65.07; H, 4.85; N, 3.72; ESI-MS:
1-(1-(4-Methoxyphenyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)- m/z ¼ 368 (M + 1)+.
ethanone (4t). Yellow solid, mp 130–132 ꢀC; IR (KBr): 2902, 1654,
1-(2,5-Dimethyl-4-phenyl-1-(4-(triuoromethyl)phenyl)-1H-
1
1514, 1383, 1247, 958, 707 cmꢁ1; H NMR (CDCl3, 500 MHz) d pyrrol-3-yl)ethanone (4z). Yellow sticky liquid; IR (KBr): 2926,
1.84 (s, 3H), 1.93 (s, 3H), 2.28 (s, 3H), 3.87 (s, 3H), 7.01 (d, J ¼ 9.0 1660, 1516, 1442, 1386, 1265, 960, 705 cmꢁ1; H NMR (CDCl3,
1
Hz, 2H), 7.17 (d, J ¼ 8.5 Hz, 2H), 7.29–7.31 (m, 3H), 7.39 (t, J ¼ 7.0 500 MHz) d 1.86 (s, 3H), 1.93 (s, 3H), 2.29 (s, 3H), 7.29–7.34 (m,
Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.1, 13.0, 30.9, 55.5, 3H), 7.41 (t, J ¼ 8.0 Hz, 4H), 7.80 (t, J ¼ 8.5 Hz, 2H) ppm; 13C
114.6, 121.6, 121.9, 126.5, 127.0, 128.2, 129.1, 130.1, 130.5, 135.2, NMR (CDCl3, 125 MHz) d 11.2, 13.0, 30.9, 122.4, 122.7, 123.6 (q,
136.9, 159.5, 197.2 ppm; anal. calcd for C21H21NO2: C, 78.97; H, 1JFC ¼ 270.7 Hz), 126.3, 126.7 (q, JFC ¼ 3.3 Hz), 126.8, 128.3,
3
6.63; N, 4.39; found: C, 78.88; H, 6.45; N, 4.32; ESI-MS: m/z ¼ 320 128.7, 130.4, 130.9 (q, 2JFC ¼ 36.0 Hz), 134.5, 136.4, 140.8, 197.3
(M + 1)+.
ppm; anal. calcd for C21H18F3NO: C, 70.58; H, 5.08; N, 3.92;
1-(1-(4-Fluorophenyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)- found: C, 70.50; H, 4.89; N, 3.82; ESI-MS: m/z ¼ 358 (M + 1)+.
ethanone (4u). Yellow solid, mp 95–96 ꢀC; IR (KBr): 2918, 1647,
1-(2,5-Dimethyl-4-phenyl-1-(4-(triuoromethoxy)phenyl)-1H-
1508, 1383, 1222, 952, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d pyrrol-3-yl)ethanone (4aa). White solid, mp 125–126 ꢀC; IR
1
1.84 (s, 3H), 1.92 (s, 3H), 2.27 (s, 3H), 7.19–7.24 (m, 4H), 7.28– (KBr): 2926, 1660, 1508, 1410, 1384, 1269, 956, 705 cmꢁ1 1H
;
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NMR (CDCl3, 500 MHz) d 1.85 (s, 3H), 1.92 (s, 3H), 2.28 (s, 3H),
7.29–7.33 (m, 5H), 7.36–7.41 (m, 4H) ppm; 13C NMR (CDCl3, 125
MHz) d 11.1, 12.9, 30.9, 119.4 (q, 1JFC ¼ 256.6 Hz), 121.8, 122.1,
122.4, 126.5, 126.7, 128.2, 129.7, 130.4, 134.7, 136.0, 136.6, 149.0,
197.3 ppm; anal. calcd for C21H18F3NO2: C, 67.55; H, 4.86; N,
3.75; found: C, 67.45; H, 4.80; N, 3.69; ESI-MS: m/z ¼ 374 (M + 1)+.
1-(1-(Furan-2-ylmethyl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)-
ethanone (4ab). White solid, mp 120–121 ꢀC; IR (KBr): 2922,
(S)-1-(2,5-Dimethyl-4-phenyl-1-(1-phenylethyl)-1H-pyrrol-3-yl)-
ethanone (4ag). Yellow solid, mp 92–93 ꢀC; IR (KBr): 2920, 1645,
1
1518, 1396, 1269, 950, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d
1.86 (s, 3H), 1.88 (s, 3H), 1.92 (d, J ¼ 7.5 Hz, 3H), 2.41 (s, 3H), 5.64
(q, J ¼ 7.0 Hz, 1H), 7.12 (d, J ¼ 7.5 Hz, 2H), 7.24 (d, J ¼ 8.0 Hz,
2H), 7.28 (t, J ¼ 6.5 Hz, 2H), 7.33–7.38 (m, 4H) ppm; 13C NMR
(CDCl3, 125 MHz) d 11.5, 12.6, 18.8, 31.2, 52.7, 122.0, 122.9,
125.9, 126.5, 127.2, 128.1, 128.7, 130.7, 134.0, 137.2, 140.9, 197.7
ppm; anal. calcd for C22H23NO: C, 83.24; H, 7.30; N, 4.41; found:
C, 83.07; H, 7.21; N, 4.30; ESI-MS: m/z ¼ 318 (M + 1)+.
1
1643, 1518, 1406, 1383, 1292, 941, 702 cmꢁ1; H NMR (CDCl3,
500 MHz) d 1.85 (s, 3H), 2.13 (s, 3H), 2.58 (s, 3H), 5.00 (s, 2H),
6.14 (d, J ¼ 7.5 Hz, 1H), 6.32 (dd, J ¼ 2.0 Hz, 3.0 Hz, 1H), 7.22–
1-(1-Cyclopropyl-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)etha-
none (4ah). Yellow sticky liquid; IR (KBr): 2924, 1647, 1516,
7.24 (m, 2H), 7.29 (t, J ¼ 7.5 Hz, 1H), 7.35–7.38 (m, 3H) ppm; 13
C
1
1465, 1384, 1151, 950, 702 cmꢁ1; H NMR (CDCl3, 500 MHz) d
NMR (CDCl3, 125 MHz) d 10.3, 11.7, 31.0, 40.6, 107.9, 110.4,
121.6, 122.2, 125.9, 126.6, 128.1, 130.6, 134.1, 137.0, 142.6, 149.9,
197.2 ppm; anal. calcd for C19H19NO2: C, 77.79; H, 6.53; N, 4.77;
found: C, 77.72; H, 6.47; N, 4.68; ESI-MS: m/z ¼ 294 (M + 1)+.
1-(1-(9H-Fluoren-2-yl)-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)-
ethanone (4ac). Yellow solid, mp 153–155 ꢀC; IR (KBr): 2922,
0.96 (q, J ¼ 5.5 Hz, 2H), 1.14 (q, J ¼ 7.0 Hz, 2H), 1.83 (s, 3H), 2.14
(s, 3H), 2.59 (s, 3H), 2.93–2.98 (m, 1H), 7.21 (d, J ¼ 7.5 Hz, 2H),
7.28 (t, J ¼ 7.5 Hz, 1H), 7.36 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR
(CDCl3, 125 MHz) d 8.1, 11.3, 13.0, 26.0, 31.0, 121.3, 121.9,
126.5, 127.9, 128.1, 130.5, 136.5, 137.1, 197.1 ppm; anal. calcd
for C17H19NO: C, 80.60; H, 7.56; N, 5.53; found: C, 80.48; H, 7.39;
N, 5.49; ESI-MS: m/z ¼ 254 (M + 1)+.
1
1654, 1518, 1489, 1357, 1265, 952, 709 cmꢁ1; H NMR (CDCl3,
500 MHz) d 1.89 (s, 3H), 1.95 (s, 3H), 2.32 (s, 3H), 3.99 (s, 2H),
7.27–7.44 (m, 9H), 7.59 (d, J ¼ 7.5 Hz, 1H), 7.83 (d, J ¼ 7.5 Hz,
1H), 7.89 (d, J ¼ 8.0 Hz, 1H) ppm; 13C NMR (CDCl3, 125 MHz) d
11.3, 13.2, 31.1, 36.9, 120.3, 120.5, 121.8, 122.2, 124.9, 125.2,
126.6, 126.9, 126.9, 127.1, 127.4, 128.3, 130.6, 135.2, 136.0,
137.0, 140.5, 142.2, 143.5, 144.5, 197.3 ppm; anal. calcd for
1-(1-Cyclopentyl-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)etha-
none (4ai). Yellow solid, mp 61–62 ꢀC; IR (KBr): 2924, 1647,
1508, 1406, 1383, 1161, 950, 704 cmꢁ1 1H NMR (CDCl3, 500
;
MHz) d 1.65–1.75 (m, 4H), 1.82 (s, 3H), 1.92–2.05 (m, 4H), 2.11
(s, 3H), 2.57 (s, 3H), 4.63–4.70 (m, 1H), 7.22 (d, J ¼ 7.0 Hz, 2H),
7.29 (t, J ¼ 7.5 Hz, 1H), 7.36 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR
(CDCl3, 125 MHz) d 11.8, 12.9, 25.2, 31.1, 56.3, 121.9, 122.9,
125.7, 126.5, 128.1, 130.6, 133.9, 137.3, 197.5 ppm; anal. calcd
for C19H23NO: C, 81.10; H, 8.24; N, 4.98; found: C, 81.10; H, 8.15;
N, 4.79; ESI-MS: m/z ¼ 282 (M + 1)+.
C
27H23NO: C, 85.91; H, 6.14; N, 3.71; found: C, 85.88; H, 6.01; N,
3.56; ESI-MS: m/z ¼ 378 (M + 1)+.
1-(1-Allyl-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)ethanone (4ad).
Yellow sticky liquid; IR (KBr): 2920, 1647, 1516, 1406, 1384, 1155,
941, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d 1.86 (s, 3H), 2.03
1
(s, 3H), 2.48 (s, 3H), 4.46 (s, 2H), 4.83 (d, J ¼ 17.0 Hz, 1H), 5.18 (d, J
¼ 10.5 Hz, 1H), 5.87–5.94 (m, 1H), 7.23 (d, J ¼ 7.0 Hz, 2H), 7.29 (t, J
¼ 7.0 Hz, 1H), 7.37 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR (CDCl3, 125
MHz) d 10.0, 11.4, 31.0, 45.7, 116.4, 121.3, 122.1, 125.7, 126.5,
128.1, 130.6, 132.6, 134.0, 137.1, 197.2 ppm; anal. calcd for
C17H19NO: C, 80.60; H, 7.56; N, 5.53; found: C, 80.57; H, 7.48; N,
5.47; ESI-MS: m/z ¼ 254 (M + 1)+.
1-(2,5-Dimethyl-4-phenyl-1-propyl-1H-pyrrol-3-yl)ethanone
(4aj). Yellow sticky liquid; IR (KBr): 2933, 1647, 1506, 1408,
1383, 1155, 950, 704 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 0.99 (t,
J ¼ 7.5 Hz, 3H), 1.67–1.74 (m, 2H), 1.84 (s, 3H), 2.06 (s, 3H), 2.52
(s, 3H), 3.77 (t, J ¼ 8.0 Hz, 2H), 7.22 (d, J ¼ 7.5 Hz, 2H), 7.28 (t,
J ¼ 7.0 Hz, 1H), 7.36 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR (CDCl3,
125 MHz) d 10.3, 11.3, 11.8, 23.8, 30.9, 45.3, 121.2, 122.1, 125.4,
126.4, 128.1, 130.6, 133.7, 137.2, 197.1 ppm; anal. calcd for
1-(1-Benzyl-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)ethanone
(4ae). Yellow sticky liquid; IR (KBr): 2918, 1647, 1516, 1406,
1155, 945, 704 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 1.90 (s, 3H),
2.00 (s, 3H), 2.47 (s, 3H), 5.11 (s, 2H), 6.97 (d, J ¼ 7.5 Hz, 2H),
7.26–7.35 (m, 6H), 7.38 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR (CDCl3,
125 MHz) d 10.3, 11.8, 31.1, 46.9, 121.6, 122.4, 125.7, 126.0,
126.6, 127.5, 128.2, 128.9, 130.6, 134.2, 136.8, 137.1, 197.3 ppm;
anal. calcd for C21H21NO: C, 83.13; H, 6.98; N, 4.62; found: C,
83.02; H, 6.91; N, 4.49; ESI-MS: m/z ¼ 304 (M + 1)+.
C
17H21NO: C, 79.96; H, 8.29; N, 5.49; found: C, 79.89; H, 8.21; N,
5.39; ESI-MS: m/z ¼ 256 (M + 1)+.
1-(1-Butyl-2,5-dimethyl-4-phenyl-1H-pyrrol-3-yl)ethanone (4ak).
Yellow sticky liquid; IR (KBr): 2931, 1647, 1512, 1408, 1383, 1155,
952, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.98 (t, J ¼ 7.5 Hz,
1
3H), 1.37–1.44 (m, 2H), 1.62–1.68 (m, 2H), 1.84 (s, 3H), 2.06 (s, 3H),
2.52 (s, 3H), 3.80 (t, J ¼ 7.0 Hz, 2H), 7.22 (d, J ¼ 7.5 Hz, 2H), 7.29 (t,
J ¼ 7.0 Hz, 1H), 7.36 (t, J ¼ 7.5 Hz, 2H) ppm; 13C NMR (CDCl3, 125
MHz) d 10.3, 11.8, 13.8, 20.1, 30.9, 32.6, 43.5, 121.2, 122.1, 125.3,
126.4, 128.1, 130.6, 133.7, 137.2, 197.1 ppm; anal. calcd for
C18H23NO: C, 80.26; H, 8.61; N, 5.20; found: C, 80.18; H, 8.47; N,
5.12; ESI-MS: m/z ¼ 270 (M + 1)+.
1-(2,5-Dimethyl-1-phenethyl-4-phenyl-1H-pyrrol-3-yl)etha-
ꢀ
none (4af). White solid, mp 124–125 C; IR (KBr): 2939, 1639,
1510, 1410, 1151, 1026, 952, 700 cmꢁ1 1H NMR (CDCl3, 500
;
MHz) d 1.86 (s, 3H), 1.93 (s, 3H), 2.49 (s, 3H), 2.94 (t, J ¼ 7.5 Hz,
2H), 4.04 (t, J ¼ 7.5 Hz, 2H), 7.11 (d, J ¼ 7.5 Hz, 2H), 7.21 (d, J ¼
Methyl-2,5-dimethyl-1,4-diphenyl-1H-pyrrole-3-carboxylate
7.5 Hz, 2H), 7.24–7.32 (m, 4H), 7.37 (t, J ¼ 7.5 Hz, 2H) ppm; 13
C
ꢀ
(4al). Yellow solid, mp 108–109 C; IR (KBr): 2918, 1685, 1525,
1
1379, 1165, 1072, 952, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d
NMR (CDCl3, 125 MHz) d 10.2, 11.8, 31.0, 36.9, 45.3, 121.5,
122.2, 125.6, 126.5, 127.0, 128.2, 128.7, 128.8, 130.6, 133.7,
137.2, 137.7, 197.1 ppm; anal. calcd for C22H23NO: C, 83.24; H,
7.30; N, 4.41; found: C, 83.07; H, 7.22; N, 4.25; ESI-MS: m/z ¼ 318
(M + 1)+.
1.88 (s, 3H), 2.31 (s, 3H), 3.61 (s, 3H), 7.24–7.30 (m, 5H), 7.36 (t, J
¼ 7.5 Hz, 2H), 7.46 (t, J ¼ 7.0 Hz, 1H), 7.51 (t, J ¼ 7.5 Hz, 2H)
ppm; 13C NMR (CDCl3, 125 MHz) d 11.3, 12.8, 50.4, 110.7, 122.4,
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126.0, 126.9, 127.5, 128.3, 128.6, 129.5, 130.4, 135.9, 136.4, 137.8, 1384, 1276, 1078, 949, 698 cmꢁ1; H NMR (CDCl3, 500 MHz) d
166.4 ppm; anal. calcd for C20H19NO2: C, 78.66; H, 6.27; N, 4.59; 0.67 (d, J ¼ 7.0 Hz, 6H), 1.63–1.68 (m, 1H), 1.86 (s, 3H), 2.33
found: C, 78.47; H, 6.09; N, 4.48; ESI-MS: m/z ¼ 306 (M + 1)+.
(s, 3H), 3.82 (d, J ¼ 6.5 Hz, 2H), 7.22–7.35 (m, 7H), 7.45 (t, J ¼ 7.5
Ethyl-2,5-dimethyl-1,4-diphenyl-1H-pyrrole-3-carboxylate Hz, 1H), 7.50 (t, J ¼ 7.0 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz)
(4am). Yellow solid, mp 83–84 ꢀC; IR (KBr): 2922, 1681, 1533, d 11.2, 12.8, 19.1, 27.6, 69.8, 111.0, 122.4, 126.0, 126.8, 127.5,
1381, 1280, 974, 702 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 1.01 (t, 128.3, 128.6, 129.5, 130.5, 135.9, 136.7, 137.8, 166.1 ppm; anal.
J ¼ 7.0 Hz, 3H), 1.87 (s, 3H), 2.31 (s, 3H), 4.07 (q, J ¼ 7.0 Hz, 2H), calcd for C23H25NO2: C, 79.51; H, 7.25; N, 4.03; found: C, 79.23;
7.23–7.26 (m, 3H), 7.29 (d, J ¼ 7.0 Hz, 2H), 7.33 (t, J ¼ 7.0 Hz, 2H), H, 7.07; N, 3.95; ESI-MS: m/z ¼ 348 (M + 1)+.
7.44 (t, J ¼ 7.5 Hz, 1H), 7.50 (t, J ¼ 8.0 Hz, 2H) ppm; 13C NMR
1-(5-Ethyl-1-(furan-2-ylmethyl)-2-methyl-4-phenyl-1H-pyrrol-3-
ꢀ
(CDCl3, 125 MHz) d 11.3, 12.7, 14.0, 59.1, 111.1, 122.4, 125.9, yl)ethanone (4as). White solid, mp 103–104 C; IR (KBr): 2929,
126.7, 127.4, 128.3, 128.6, 129.5, 130.5, 135.7, 136.5, 137.8, 165.9 1647, 1498, 1406, 1151, 1010, 704 cmꢁ1; H NMR (CDCl3, 500
1
ppm; anal. calcd for C21H21NO2: C, 78.97; H, 6.63; N, 4.39; found: MHz) d 1.01 (t, J ¼ 7.5 Hz, 3H), 1.82 (s, 3H), 2.49 (q, J ¼ 7.5 Hz,
C, 78.89; H, 6.56; N, 4.28; ESI-MS: m/z ¼ 320 (M + 1)+.
2H), 2.55 (s, 3H), 5.02 (s, 2H), 6.09 (t, J ¼ 2.5 Hz, 1H), 6.32 (dd, J ¼
2-Methoxyethyl
2,5-dimethyl-1,4-diphenyl-1H-pyrrole-3- 1.5, 3.0 Hz, 1H), 7.24–7.26 (m, 2H), 7.30 (t, J ¼ 7.0 Hz, 1H), 7.35–
carboxylate (4an). Yellow solid, mp 72–73 ꢀC; IR (KBr): 2922, 7.38 (m, 3H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.7, 15.3, 17.6,
1701, 1384, 1274, 1078, 846, 702 cmꢁ1 1H NMR (CDCl3, 500 31.0, 40.6, 107.7, 110.4, 121.8, 122.0, 126.7, 128.1, 130.5, 131.8,
;
MHz) d 1.85 (s, 3H), 2.30 (s, 3H), 3.18 (s, 3H), 3.34 (t, J ¼ 5.0 Hz, 134.3, 137.1, 142.4, 150.1, 197.2 ppm; anal. calcd for C20H21NO2:
2H), 4.17 (t, J ¼ 5 Hz, 2H), 7.22–7.26 (m, 3H), 7.29 (d, J ¼ 7.0 Hz, C, 78.15; H, 6.89; N, 4.56; found: C, 78.11; H, 6.76; N, 6.82;
2H), 7.33 (t, J ¼ 7.5 Hz, 2H), 7.44 (t, J ¼ 7.5 Hz, 1H), 7.49 (t, J ¼ ESI-MS: m/z ¼ 308 (M + 1)+.
7.5 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.2, 12.7, 58.7,
1-(1-Benzyl-5-ethyl-2-methyl-4-phenyl-1H-pyrrol-3-yl)ethanone
62.3, 70.3, 110.6, 122.4, 125.9, 126.8, 127.4, 128.3, 128.6, 129.4, (4at). Yellow sticky liquid; IR (KBr): 2931, 1653, 1498, 1398, 1415,
1
130.5, 136.1, 136.4, 137.8, 165.7 ppm; anal. calcd for C22H23NO3: 952, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.95 (t, J ¼ 7.5 Hz,
C, 75.62; H, 6.63; N, 4.01; found: C, 76.48; H, 6.45; N, 3.92; ESI- 3H), 1.87 (s, 3H), 2.37 (q, J ¼ 7.5 Hz, 2H), 2.42 (s, 3H), 5.13 (s, 2H),
MS: m/z ¼ 350 (M + 1)+.
6.94 (t, J ¼ 7.5 Hz, 2H), 7.25–7.34 (m, 6H), 7.38 (t, J ¼ 7.5 Hz, 2H)
Allyl-2,5-dimethyl-1,4-diphenyl-1H-pyrrole-3-carboxylate (4ao). ppm; 13C NMR (CDCl3, 125 MHz) d 11.8, 15.6, 17.7, 31.1, 46.8,
Yellow sticky liquid; IR (KBr): 2920, 1685, 1508, 1384, 1273, 1172, 121.7, 122.2, 125.5, 126.7, 127.4, 128.1, 128.9, 130.6, 132.1, 134.4,
1
927, 698 cmꢁ1; H NMR (CDCl3, 500 MHz) d 1.88 (s, 3H), 2.32 137.1, 137.2, 197.3 ppm; anal. calcd for C22H23NO: C, 83.24; H,
(s, 3H), 4.55 (d, J ¼ 5.0 Hz, 2H), 4.97 (dd, J ¼ 1.5, 17.0 Hz, 1H), 7.30; N, 4.41; found: C, 83.29; H, 7.25; N, 4.33; ESI-MS: m/z ¼ 318
5.01 (d, J ¼ 10.5 Hz, 1H), 5.68–5.76 (m, 1H), 7.45–7.26 (m, 3H), (M + 1)+.
7.30 (d, J ¼ 7.0 Hz, 2H), 7.34 (t, J ¼ 7.5 Hz, 2H), 7.46 (t, J ¼ 7.0 Hz,
1-(1-Cyclopropyl-5-ethyl-2-methyl-4-phenyl-1H-pyrrol-3-yl)-
1H), 7.51 (t, J ¼ 7.0 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d ethanone (4au). Yellow sticky liquid; IR (KBr): 2931, 1647, 1516,
11.2, 12.8, 64.1, 110.7, 116.8, 122.4, 126.0, 126.9, 127.5, 128.3, 1413, 1163, 1016, 704 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.99
1
128.6, 129.5, 130.5, 132.6, 136.1, 136.4, 137.8, 165.6 ppm; anal. (q, J ¼ 5.0 Hz, 2H), 1.08 (t, J ¼ 7.5 Hz, 3H), 1.15 (q, J ¼ 7.0 Hz,
calcd for C22H21NO2: C, 79.73; H, 6.39; N, 4.23; found: C, 79.70; H, 2H), 1.80 (s, 3H), 2.56 (q, J ¼ 7.5 Hz, 2H), 2.58 (s, 3H), 2.97–3.01
6.25; N, 4.11; ESI-MS: m/z ¼ 332 (M + 1)+.
(m, 1H), 7.22 (d, J ¼ 7.0 Hz, 2H), 7.29 (t, J ¼ 7.0 Hz, 2H), 7.36 (d,
Methyl-2-ethyl-5-methyl-1,4-diphenyl-1H-pyrrole-3-carboxylate J ¼ 7.0 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 8.0, 13.3,
ꢀ
(4ap). Yellow solid, mp 100–101 C; IR (KBr): 2916, 1685, 1523, 14.8, 18.1, 26.2, 31.0, 121.4, 121.7, 126.6, 128.1, 130.5, 133.8,
1
1284, 1155, 1072, 983, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d 136.7, 137.2, 197.1 ppm; anal. calcd for C18H21NO: C, 80.86; H,
1.04 (t, J ¼ 7.0 Hz, 3H), 1.85 (s, 3H), 2.74 (q, J ¼ 7.5 Hz, 2H), 3.61 7.92; N, 5.24; found: C, 80.71; H, 7.75; N, 5.08; ESI-MS: m/z ¼ 268
(s, 3H), 7.24–7.31 (m, 5H), 7.36 (t, J ¼ 7.5 Hz, 2H), 7.46–7.52 (M + 1)+.
(m, 3H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.2, 14.7, 19.5, 50.4,
1-(5-Ethyl-2-methyl-4-phenyl-1-propyl-1H-pyrrol-3-yl)ethanone
109.8, 122.3, 125.9, 126.9, 127.4, 128.5, 128.7, 129.4, 130.4, 136.4, (4av). Yellow sticky liquid; IR (KBr): 2974, 1647, 1550, 1452, 1288,
1
137.8, 142.0, 166.1 ppm; anal. calcd for C21H21NO2: C, 78.97; H, 952, 700 cmꢁ1; H NMR (CDCl3, 500 MHz) d 0.99 (t, J ¼ 7.5 Hz,
6.63; N, 4.39; found: C, 78.90; H, 6.55; N, 4.29; ESI-MS: m/z ¼ 320 3H), 1.03 (t, J ¼ 7.5 Hz, 3H), 1.68–1.76 (m, 2H), 1.81 (s, 3H), 2.42
(M + 1)+.
(q, J ¼ 7.5 Hz, 2H), 2.52 (s, 3H), 3.77 (t, J ¼ 8.0 Hz, 3H), 7.23–7.26
tert-Butyl-2,5-dimethyl-1,4-diphenyl-1H-pyrrole-3-carboxylate (m, 2H), 7.30 (t, J ¼ 7.5 Hz, 1H), 7.36 (t, J ¼ 7.5 Hz, 2H) ppm; 13
C
(4aq). Yellow solid, mp 96–97 ꢀC; IR (KBr): 2926, 1685, 1541, NMR (CDCl3, 125 MHz) d 11.3, 11.9, 15.5, 17.6, 24.2, 30.9, 45.2,
1384, 1288, 1159, 1080, 698 cmꢁ1; 1H NMR (CDCl3, 500 MHz) d 121.5, 121.8, 126.5, 128.1, 130.6, 131.4, 133.7, 137.4, 197.0 ppm;
1.26 (s, 9H), 1.87 (s, 3H), 2.30 (s, 3H), 7.23–7.26 (m, 3H), 7.29 (d, anal. calcd for C18H23NO: C, 80.26; H, 8.61; N, 5.20; found: C,
J ¼ 7.0 Hz, 2H), 7.35 (t, J ¼ 7.5 Hz, 2H), 7.44 (t, J ¼ 7.5 Hz, 1H), 80.15; H, 8.47; N, 5.02; ESI-MS: m/z ¼ 270 (M + 1)+.
7.49 (t, J ¼ 8.0 Hz, 2H) ppm; 13C NMR (CDCl3, 125 MHz) d 11.2,
12.4, 28.0, 79.2, 112.7, 122.1, 125.8, 126.4, 127.5, 128.3, 128.5,
129.4, 130.4, 135.2, 136.9, 137.9, 165.5 ppm; anal. calcd for
Acknowledgements
C23H25NO2: C, 79.51; H, 7.25; N, 4.03; found: C, 79.33; H, 7.09; N, We gratefully acknowledge the nancial supports by the
3.92; ESI-MS: m/z ¼ 348 (M + 1)+.
National Natural Science Foundation of China (NNSFC) (no.
21272053 and 21072042) and Nature Science Foundation of
Isobutyl-2,5-dimethyl-1,4-diphenyl-1H-pyrrole-3-carboxylate
(4ar). Yellow solid, mp 70–71 ꢀC; IR (KBr): 2933, 1685, 1527, Hebei Province (no. B2011205031).
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