Aluminosilicates with Different Porous Structures in the Synthesis of 2-Ethyl-3-Methylquinoline

Article abstract of DOI:10.1134/S0965544119070065

Abstract: The catalytic properties of microporous zeolites of different structural types (FAU, BEA, MOR, and MFI), a micro–meso–macroporous zeolite (H-Ymmm), and an ASM mesoporous aluminosilicate in the reaction of aniline with propionic aldehyde have been studied. It has been found that the reaction proceeds with a high conversion of aniline (90–99% over zeolites and 71% over an ASM aluminosilicate) to form two main products, namely, 2-ethyl-3-methylquinoline (2) and 2-ethyl-3-methyl-N-phenyl-1,2,3,4-tetrahydroquinoline-4-amine (3). The most selective catalysts for the synthesis of quinoline 2 are H-Y (up to 64%) and H-Ymmm (59%) zeolites and the ASM aluminosilicate (50%). It has been shown that an increase in the quinoline 2 selectivity is promoted by an increase in the catalyst acidity, in the reaction temperature to 160°C, in the catalyst concentration to 20 wt %, and in the aniline : aldehyde molar ratio to 1 : 2.

Full text of DOI:10.1134/S0965544119070065

ISSN 0965-5441, Petroleum Chemistry, 2019, Vol. 59, No. 7, pp. 719–725. © Pleiades Publishing, Ltd., 2019.
Russian Text © The Author(s), 2019, published in Neftekhimiya, 2019, Vol. 59, No. 4, pp. 437–444.
Aluminosilicates with Different Porous Structures
in the Synthesis of 2-Ethyl-3-Methylquinoline
N. G. Grigor’evaa, *, S. A. Kostylevaa, A. R. Gataulina, A. N. Khazipovaa,
Nama Narenderb, and B. I. Kutepova
aInstitute of Petroleum Chemistry and Catalysis, Ufa Federal Research Center, Russian Academy of Sciences,
Ufa, Bashkortostan, 450075 Russia
bCSIR-Indian Institute of Chemical Technology, Hyderabad, Tarnaka, 500-007 India
*e-mail: ngg-ink@mail.ru
Received September 11, 2018; revised February 24, 2019; accepted March 14, 2019
Abstract—The catalytic properties of microporous zeolites of different structural types (FAU, BEA, MOR,
and MFI), a micro–meso–macroporous zeolite (H-Ymmm), and an ASM mesoporous aluminosilicate in
the reaction of aniline with propionic aldehyde have been studied. It has been found that the reaction pro-
ceeds with a high conversion of aniline (90–99% over zeolites and 71% over an ASM aluminosilicate) to form
two main products, namely, 2-ethyl-3-methylquinoline (2) and 2-ethyl-3-methyl-N-phenyl-1,2,3,4-tetra-
hydroquinoline-4-amine (3). The most selective catalysts for the synthesis of quinoline 2 are H-Y (up to
64%) and H-Ymmm (59%) zeolites and the ASM aluminosilicate (50%). It has been shown that an increase
in the quinoline 2 selectivity is promoted by an increase in the catalyst acidity, in the reaction temperature to
160°C, in the catalyst concentration to 20 wt %, and in the aniline : aldehyde molar ratio to 1 : 2.
Keywords: quinolines, 1,2,3,4-tetrahydroquinolines, aniline, aldehydes, condensation, zeolites, hierarchal
zeolites, mesoporous aluminosilicates
DOI: 10.1134/S0965544119070065
Quinoline and its derivatives are widely used for the
In this connection, the search for and development
production of highly efficient medicines possessing of highly efficient heterogeneous catalysts and meth-
antibacterial, fungicidal, antiparasitic, and antineo- ods for the synthesis of alkylquinolines on their basis
plastic activities [1–3]. Corrosion inhibitors, preserv- are important and relevant tasks.
ing agents, resin solvents, refinery defoamers [4], and
luminescent materials [5] are produced on the basis of
quinolines.
In this paper we present the results of the investiga-
tion of the activity and selectivity of various crystalline
and amorphous aluminosilicates differing in texture,
porosity, and acid properties, namely, microporous
zeolites (H-Y, H-Beta, H-MOR, and H-ZSM-5), a
H-Ymmm micro–meso–macroporous zeolite, as well
as an ASM mesoporous aluminosilicate in the synthe-
sis of 2-ethyl-3-methylquinoline 2 via the reaction of
aniline with propionic aldehyde.
Various methods have been proposed for the syn-
thesis of quinolines, namely, Skraup, Knorr, Doeb-
ner–Miller, Friedländer, Combes, Pfitzinger, and
Conrad–Limpach [6]; however, most of them are
characterized by the use of acids or bases as catalysts,
multistage nature, harsh reaction conditions, and
low yields. The preparation of 2-ethyl-3-methylquin-
oline 2 (yield, 59%) from aniline and propionic alde-
hyde in the presence of the metal complex catalyst
[Rh(norbornadiene)Cl]2 is known [7].
EXPERIMENTAL
Chemicals and Catalysts
Aniline (99.8 wt %) and propionic aldehyde
(97 wt %) (Acros) were used in this study.
Zeolites of the FAU (H-Y and H-Ymmm),
BEA (H-Beta), MFI (H-ZSM-5), and mordenite
(H-MOR) structural types and an ASM amorphous
mesoporous aluminosilicate were investigated as
the catalysts.
Zeolite Na-Y (SiO2/Al2O3 = 5.0) was synthesized
according to a procedure described in [11] and con-
Works, in which zeolites were used for the synthesis
of quinoline derivatives, are still scarce [8, 9]. Thus,
the synthesis of 2- and 4-methylquinolines via the
reaction of aniline with acetaldehyde over H-Beta
zeolite with an overall yield of 83% was reported [9].
Guo et al. [10] developed a method for the synthesis of
substituted alkylquinolines in a yield of 29–81%
from arylamines and aldehydes over a mesoporous
MCM-41/Cp2ZrCl2 material.
719

720
GRIGOR’EVA et al.
verted into the H-form by triple ion exchange in a autoclave. Upon completion of the reaction, the reac-
solution of NH4NO3 at 70°C to the degree of deca-
tionation of αNa = 0.80. Samples of H-Beta
(SiO2/Al2O3 = 40) and H-ZSM-5 (SiO2/Al2O3 = 50)
tion mixture was cooled to room temperature, the cat-
alyst was filtered off, and the residue was chromato-
graphed on a SiO2 column (the eluent is hexane →
zeolites were prepared using ion exchange of Na+ cat- hexane–ethyl acetate blend).
+
ions to
cations in the samples of Na-Beta and
NH4
The GLC analysis of the products was performed
on a Shimadzu GC-9A chromatograph with a flame
ionization detector, a 3-m packed column, the SE-30
phase, programming at 50–250°C, and helium as the
carrier gas.
Na-ZSM-5 (Zeolyst) followed by the thermal treat-
ment of the obtained ammonium form. A Na-MOR
zeolite (SiO2/Al2O3 = 10.0) was synthesized according
to a procedure described in [12] and transformed to
+
the H-form using ion exchange of Na+ cations to
NH4
The 1H and 13C NMR spectra in the COSY,
HSQC, and HMBC homo- and heteronuclear modes
were recorded on Bruker Avance-400 (operating fre-
quency of 400.13 MHz for 1H and 100.62 MHz for 13C)
and Bruker Avance III 500 HD Ascend (operating fre-
quency of 500.17 MHz for 1H and 125.78 MHz for 13C)
instruments; the solvent was CDCl3.
cations followed by the thermal treatment of the
obtained ammonium form.
The procedure for preparing Ymmm micro–
meso–macroporous zeolite in the H-form
(SiO2/Al2O3 = 7.2) is described in [13] and is based on
the selective crystallization of granules consisting of
finely divided Na-Y zeolite and amorphous binder
(metakaolin) in sodium silicate solutions at 96–98°C.
Samples of H-Ymmm zeolites with αNa of 0.5, 0.6,
0.75, and 0.95 were prepared using ion exchange of a
sample of Na-Ymmm; hereinafter, these samples are
denoted as 0.5H-Ymmm, 0.6H-Ymmm, 0.75H-
Ymmm, and 0.95H-Ymmm.
The amorphous mesoporous aluminosilicate ASM
(SiO2/Al2O3 = 20) was obtained via sol–gel synthesis
according to a procedure described in [14, 15].
Prior to catalytic tests, the catalysts were subjected
to high-temperature treatment in a dry air atmosphere
at 540°C for 3 to 4 h.
N-Propylaniline (1). Yield 2–11% depending on
the catalyst type. An oily yellow liquid. Tb
1
96°C/10 mmHg. H NMR spectrum (500.17 MHz,
CDCl3, δ, ppm): 1.04 (t, J = 7.3 Hz, 3H), 1.69 (m,
2H), 3.12 (t, J = 7.0 Hz, 1H), 6.70 (d, J = 7.5 Hz, 2H),
6.73 (t, J = 7.3 Hz, 1H), 7.21 (t, J = 7.8 Hz, 2H).
13C NMR spectrum (125.78 MHz, CDCl3, δ, ppm):
11.67, 22.75, 45.83, 112.73, 117.11, 129.24, 129.41,
148.52. The obtained data correspond to the published
data [17].
2-Ethyl-3-methylquinoline (2). Yield 23–62%
depending on the catalyst type. An oily yellow liquid.
Tb 97–99°C/2 mmHg. 1H NMR spectrum
(500.17 MHz, CDCl3, δ, ppm): 1.41 (t, J = 7.5 Hz,
3H), 2.48 (s, 3H), 3.01 (quartet, J = 7.5 Hz, 2H), 7.46
(t, J = 7.5 Hz, 1H), 7.62 (t, J = 8.0 Hz, 1H), 7.70 (d,
J = 8.0 Hz, 1H), 7.81 (s, 1H), 8.06 (d, J = 8.5 Hz, 1H).
13C NMR spectrum (125.78 MHz, CDCl3, δ, ppm):
Catalyst Investigation Methods
To study the physicochemical properties of the pre-
pared samples of zeolites and mesoporous aluminosil-
icate, X-ray fluorescent, X-ray phase, and X-ray
structural analyses, 27Al MAS NMR spectroscopy,
scanning electron microscopy, low-temperature
adsorption–desorption of nitrogen, and temperature-
programmed desorption of ammonia (TPD-NH3) 12.86, 19.11, 29.51, 125.61, 126.71, 127.34, 128.30,
128.54, 129.41, 135.75, 146.67, 163.28. The obtained
data correspond to the published data [18].
were used. Methods for the investigation of the physi-
cochemical properties of the studied zeolite catalysts
are described in [13, 16], and the mesoporous alumi-
nosilicate, in [14, 15].
2-Ethyl-3-methyl-N-phenyl-1,2,3,4-tetrahydro-
quinoline-4-amine (3). Yield 5–34% depending on the
catalyst type. Transparent crystals. Tm 104–106°C.
Synthesis of N-Propylaniline, 2-Ethyl-3-
Methylquinoline, and 2-Ethyl-3-Methyl-N-Phenyl-
1,2,3,4-Tetrahydroquinoline-4-Amine
A metal autoclave was charged with 0.25 mL
(2.8 mmol) of aniline and then 0.20–0.60 mL (2.8–
8.4 mmol) of propionic aldehyde depending on the
required molar ratio, 1 mL of chlorobenzene, and the
test catalyst in an amount of 10–50% of weight of the
reactant mixture; tightly sealed; and placed into a
thermostated cabinet. The reaction was carried out at
1H NMR spectrum (500.17 MHz, CDCl3, δ, ppm):
1.01 (t, J = 9.5 Hz, 3H), 1.11 (d, J = 8.5 Hz, 3H), 1.61–
1.67 (m, 2H), 1.88–1.94 (m, 1H), 3.14–3.18 (m, 1H),
3.85 (br. s, 2H), 4.34 (d, J = 11.5 Hz, 1H), 6.55 (d, J =
10.0 Hz, 2H), 6.62–6.77 (m, 2H), 7.06 (t, J = 8.8 Hz,
1H), 7.19–7.27 (m, 4H). 13C NMR spectrum
(125.78 MHz, CDCl3, δ, ppm): 9.12, 15.76, 26.49,
37.39, 56.44, 57.86, 112.50, 113.25, 113.86, 116.85,
117.36, 123.38, 128.05, 128.31, 129.40, 129.45, 144.37,
25–200°C for 6 h with continuous rotation of the 148.76.
PETROLEUM CHEMISTRY
Vol. 59
No. 7
2019

ALUMINOSILICATES WITH DIFFERENT POROUS STRUCTURES
Table 1. Physicochemical characteristics of the catalysts
721
Acid properties
concentration of acid sites, μmol g−1
Equilibrium adsorption capacity (20°C
and P/Ps = 0.8), cm3/g, for vapors of
Crystallinity,
rel. %
SBET, m2/g
*
Catalyst
H2O
C6H6
CI
CII
C
H-Y
H-Beta
H-MOR
H-ZSM-5
0.5H-Ymmm
0.6H-Ymmm
0.75H-Ymmm
0.95H-Ymmm
ASM
100
100
100
100
93
93
93
93
0
870
625
393
360
–
–
–
741
640
0.30
0.12
0.18
0.14
0.30
0.29
0.29
0.25
–
0.30
0.32
0.16
0.15
0.30
0.30
0.31
0.30
–
610
520
651
270
450
460
480
515
350
520
310
349
190
340
390
410
460
120
1130
830
1000
460
790
850
890
975
470
* C , C , and C are the concentrations of weak and strong acid sites and the total concentration, respectively.
I
II
RESULTS AND DISCUSSION
[19]. In the series of microporous zeolites, the concentra-
tion of strong acid sites, which are the most important for
catalytic transformations, decreases in the following
order: H-Y > H-MOR > H-Beta > H-ZSM-5. The total
concentration of acid sites changes in a similar manner.
There are two peaks in the acidity spectra of the sam-
ples of a H-Ymmm zeolite, which characterize weak acid
sites with a temperature maximum in the temperature
range of 250–280°C and strong acid sites at temperatures
of 350–420°C. The concentration of strong acid sites in
the H-Ymmm zeolite increases with an increase in the
degree of decationation.
According to the data presented in Table 1, the meso-
porous aluminosilicate ASM possesses the lowest acidity
among the studied catalysts because (a) it contains the
smallest number of strong acid sites (they are generally
responsible for the occurrence of reactions) and (b) the
strength of the specified acid sites is lower compared to
the zeolites, as evidenced by the shift of the high-tem-
perature peak to lower temperatures.
Catalyst Characterization
The physicochemical properties of the studied H-Y,
H-Beta, H-ZSM-5, H-MOR, and H-Ymmm zeolites
with different αNa values and the ASM mesoporous alu-
minosilicate are presented in Table 1.
According to the XRD data and values of the adsorp-
tion capacity for H2O and C6H6 vapors, H-Y, H-Beta,
H-MOR, and H-ZSM-5 zeolites are characterized by
crystallinity close to 100% whereas for the H-Ymmm
zeolite samples have a crystallinity of 93%, which is
explained by the partial crystallization of its amorphous
component.
According to the data of low-temperature adsorp-
tion–desorption of nitrogen, the “apparent” BET
specific surface area of the zeolites is 870 (H-Y), 625
(H-Beta), 360 (H-ZSM-5), 393 (H-MOR), or 741
(H-Ymmm) m2/g (Table 1). The specific surface area
of H-Ymmm zeolite macropores determined
using mercury porosimetry is 12.1 m2/g. The micro-,
meso-, and macropore volumes are 0.28, 0.15, and
0.15 cm3/g, respectively.
Detailed information about the texture and acid
properties of the ASM aluminosilicate is set forth in [15].
Note that the ASM sample is characterized by narrow
distribution of mesopores from 2 to 5 nm with a volume
of 0.70 cm3/g.
Catalytic Properties of the Zeolites and the Mesoporous
Aluminosilicate in the Reaction of Aniline
with Propionic Aldehyde
It has been found that the main products of the
reaction of aniline with propionic aldehyde in the
presence of the studied catalysts are 2-ethyl-3-meth-
ylquinoline
2
and 2-ethyl-3-methyl-N-phenyl-
The acid properties of the samples of the zeolites and
a mesoporous aluminosilicate were studied by TPD-
NH3. Two peaks are observed in the TPD-NH3 spectra
of the microporous zeolites, namely, a low-temperature
peak with a maximum at 250–300°C and a high-tem-
perature peak with a maximum in the range of 410–
480°C. This gives evidence for the presence of two types
of acid sites, namely, weak sites that are characterized by
a low-temperature peak and strong sites characterized by
1,2,3,4-tetrahydroquinoline-4-amine 3 (Scheme 1).
In addition to them, N-propylaniline 1, condensation
products of propionic aldehyde, and 2,3-dialkyldihy-
droquinoline were identified in the reaction mass. In
Table 2 that presents the results of the investigation of
the catalytic properties of the zeolites and a meso-
porous aluminosilicate, all the reaction products
except for compounds 1–3 are summarized and
a high-temperature peak, in the samples under study denoted as “others”.
PETROLEUM CHEMISTRY Vol. 59 No. 7 2019

722
GRIGOR’EVA et al.
Table 2. Reaction of aniline with propionic aldehyde in the presence of zeolites and mesoporous aluminosilicate
Synthesis conditions: molar ratio aniline : aldehyde = 1 : 2, 20 wt % catalyst, 160°C, the solvent is chlorobenzene, 6 h
selectivity of formation, %
conversion
of aniline, %
catalyst
1
2
3
Others
H-Y
H-Beta
H-MOR
H-ZSM-5
0.95H-Ymmm
ASM
97
99
99
90
95
71
5
2
1
7
4
64
46
32
39
59
50
15
20
34
28
14
7
16
32
33
26
23
28
15
Ar
HN
O
+
NH2
+
+
N
H
H
N
N
H
1
2
3
Scheme 1. The reaction of aniline with propionic aldehyde.
The product composition indicates that in the case hyde proceeds through Schiff base (4) which is then
of aniline reaction with propionic aldehyde, the reac-
tions of linear homo- and heterocondensation, cyclo-
condensation, dimerization, rearrangement, etc. pro-
ceed simultaneously. The presence of tetrahydroquin-
oline 3 among the products confirms the 2-ethyl-3-
methylquinoline formation mechanism proposed in
[20] and depicted in Scheme 2. According to this
transformed to N-propylamine 1 and dimer (5). The
latter forms a complex with the catalyst (6), from
which compound (7) is produced as a result of intra-
molecular cyclization. The subsequent reductive elim-
ination of the catalyst in compound 7 leads to tetrahy-
droquinoline 3, which transforms into desired dial-
mechanism, the interaction of aniline with the alde- kylquinoline 2 as a result of elimination of aniline.
N
N
O
N
N
−H2O
NH2
4
5
H
[Kt]
H
[Kt]
N
N
HN
[Kt]
−H2
−[Kt]
−ArNH2
N
N
H
N
H
N
H
6
7
3
2
Scheme 2. The proposed mechanism of formation of 2-ethyl-3-methylquinoline 2.
The reaction of aniline with propionic aldehyde in oporous aluminosilicate, which is apparently due to
the low acidity of this catalyst.
the presence of all the zeolite catalysts studied pro-
ceeds with a high aniline conversion (Table 2), which
is almost complete over H-Y, H-Beta, and H-MOR
zeolites and is somewhat lower (90–95%) over
H-ZSM-5 and H-Ymmm zeolites. The lowest conver-
Dialkylquinoline 2 is the most selectively formed
over H-Y and H-Ymmm zeolites (64% and 59%,
respectively). The mesoporous aluminosilicate ASM
has selectivity (50%) close to that of the aforemen-
sion of aniline (71%) was observed over the ASM mes- tioned zeolites. The other catalysts were less selective
PETROLEUM CHEMISTRY
Vol. 59
No. 7
2019

ALUMINOSILICATES WITH DIFFERENT POROUS STRUCTURES
723
97
95
100
90
80
70
60
50
40
30
20
10
0
95
93
93
Aniline conversion, %
N-Propylaniline 1
64
59
2-Ethyl-3-methylquinoline 2
43
40
38 38
21
31
28
25
2-Ethyl-3-methyl-N-phenyl-
1,2,3,4-THQ-4-amine 3
26
23
14
16
15
Others
5
4
4
3
3
B
C
D
E
Catalyst
А
Fig. 1. The influence of the degree of decationation α of a H-Ymmm zeolite on the conversion of aniline and the product com-
Na
position. The catalyst is (A) H-Y, (B) 0.5H-Ymmm, (C) 0.6H-Ymmm, (D) 0.75H-Ymmm, and (E) 0.95H-Ymmm. Synthesis
conditions: aniline : aldehyde molar ratio = 1 : 2, 20 wt % catalyst, 160°C, the solvent chlorobenzene, 6 h.
for dialkylquinoline 2. A mixture of dialkylquinoline 2 increase in αNa, and the concentration of tetrahydro-
and tetrahydroquinoline 3 in a ~1 : 1 ratio was
obtained over the H-MOR zeolite, which exhibited
the lowest dialkylquinoline 2 selectivity.
quinoline 3 decreases. Such a character of change in
the concentration of 3 confirms that it is intermediate
in the course of formation of quinoline 2. With the
increase in αNa, the concentration of the acid sites in
the H-Ymmm zeolite increases (Table 1); therefore, a
higher concentration of acid sites is required for more
complete transformation of tetrahydroquinoline 3 to
quinoline 2.
Based on this, the low selectivity for quinoline 2 in
the presence of the H-MOR zeolite possessing a quite
high concentration of acid sites can be explained by
the inaccessibility of the active sites inside the chan-
nels for the bulky molecules of tetrahydroquinoline 3
and the occurrence of the reaction mainly over weaker
surface active sites.
The influence of temperature, molar ratio of the
reactants, and catalyst concentration on the aniline
conversion of and selectivity for the products was stud-
ied using the 0.95H-Ymmm zeolite as an example.
The reaction of aniline with propionic aldehyde
intensely occurs already at 20°C (Fig. 2), with the
selectivity for quinoline 2 being 40% and tetrahydro-
quinoline 3 appearing in a significant amount (28%)
in the reaction mixture. Increasing the temperature
from 20 to 180°C leads to an increase in the conversion
of aniline and a growth in the quinoline 2 selectivity ,
with the concentration of tetrahydroquinoline 3
decreasing to 9%.
The difference in selectivity for quinoline 2
between the catalysts is presumably due to the differ-
ences in their porous structure. Quinoline 2 is formed
most selectively over wide-pore catalysts, namely, the
H-Y zeolite possessing the greatest diameter of the
entrance windows in the series of the tested zeolite cat-
alysts; the H-Ymmm zeolite, the microporous struc-
ture of which is combined with meso- and macropo-
res; and the ASM amorphous mesoporous aluminos-
ilicate. The low selectivity for quinoline
2
demonstrated by H-MOR and H-ZSM-5 zeolites is
apparently associated with the structural characteris-
tics of their crystal lattice as well. The H-MOR zeolite
has a unidimensional channel structure rather than a
three-dimensional structure like the other catalysts
studied. This characteristic feature of the H-MOR
zeolite, as well as the presence of narrow tortuous
channels in the H-ZSM-5 zeolite lattice, can lead to
the complication of the diffusion of reactant and prod-
uct molecules inside the zeolite crystalline framework.
Since the catalytic properties of zeolites in the H-
form are associated with the presence of acid sites in
their cavities and channels, it was of interest to study
the influence of the concentration of acid sites of the
samples on their activity and selectivity in the reaction
of aniline with propionic aldehyde (Fig. 1). It has been
shown by the example of four H-Ymmm zeolite sam-
ples differing in the degree of exchange of Na+ for H+
ions (αNa = 0.5, 0.6, 0.75, and 0.95) that under the
studied conditions, the conversion of aniline little
depends on αNa and is high (93–95%) over all the
The study of the influence of the catalyst concen-
tration has shown that quinoline 2 is the most selec-
tively formed in the presence of 20% H-Ymmm zeolite
(Fig. 3). Both a decrease in the amount of the catalyst
to 10% and its increase to 50% lead to a decrease in
the quinoline 2 selectivity. The conversion of
samples. The concentration of quinoline 2 in the reac- aniline in the studied range of catalyst concentrations
tion products increases (from 25 to 59%) with the is 92–97%.
PETROLEUM CHEMISTRY Vol. 59 No. 7 2019

724
GRIGOR’EVA et al.
96
95
100
90
80
70
60
50
40
30
20
10
0
95
94
Aniline conversion, %
N-Propylaniline 1
89
60
59
52
2-Ethyl-3-methylquinoline 2
43
40
29
30
2-Ethyl-3-methyl-N-phenyl-
1,2,3,4-THQ-4-amine 3
28
26
19
25
23
14
22
9
10
Others
4
3
2
2
49
120
160
180
Temperature, °С
20
Fig. 2. The influence of the reaction temperature on the yield and composition of the products. Synthesis conditions: aniline :
aldehyde = molar ratio 1 : 2, 20 wt % catalyst, the solvent chlorobenzene, 6 h.
98
95
100
92
Aniline conversion, %
90
80
N-Propylaniline 1
70
59
60
50
2-Ethyl-3-methylquinoline 2
50
43
38
40
2-Ethyl-3-methyl-N-phenyl-
1,2,3,4-THQ-4-amine 3
30
25
23
20
14
14
12
11
Others
7
10
0
4
20
50
Concentration of H-Ymmm, %
10
Fig. 3. The influence of the concentration of the catalyst on the yield and composition of the products. Synthesis conditions: ani-
line : aldehyde molar ratio = 1 : 2, 160°C, the solvent chlorobenzene, 6 h.
Increasing the aniline : aldehyde molar ratio from sation reaction of aniline with propionic aldehyde. It
equimolar to 1 : 3 leads to an increase in the aniline
conversion (89–97%); however, a large excess of the
aldehyde promotes the formation of propanal conden-
sation products, so that the selectivity for the target
quinolines decreases. The optimum aniline : aldehyde
ratio is 1 : 2 (Fig. 4).
has been found that 2-ethyl-3-methylquinoline 2 and
2-ethyl-3-methyl-N-phenyl-1,2,3,4-tetrahydroquin-
oline-4-amine 3 are the main products in the presence
of the test catalysts. 2-Ethyl-3-methylquinoline 2 is
the most selectively formed over wide-pore catalysts,
namely, the H-Y zeolite (64% at an aniline conversion
of 97%), the micro–meso–macroporous zeolite H-
Ymmm (59% at an aniline conversion of 95%), and
the mesoporous aluminosilicate ASM (50% at an ani-
line conversion of 71%). Tetrahydroquinoline-4-
amine 3 formed converts into quinoline 2 during the
course of the reaction. The open three-dimensional
In summary, the study has revealed as a result an
interrelation of the acid properties and characteristics
of the porous structure of various zeolite catalysts
having microporous (H-Y, H-Beta, H-MOR, and
H-ZSM-5) and hierarchal (H-Ymmm) structures and
the amorphous mesoporous aluminosilicate ASM
with their activity and selectivity in the cycloconden- system of wide-pore channels or cavities, the presence
PETROLEUM CHEMISTRY
Vol. 59
No. 7
2019

ALUMINOSILICATES WITH DIFFERENT POROUS STRUCTURES
725
97
Aniline conversion, %
95
100
80
60
40
20
0
89
N-Propylaniline 1
59
49
2-Ethyl-3-methylquinoline 2
44
36
32
23
2-Ethyl-3-methyl-N-phenyl-
1,2,3,4-THQ-4-amine 3
14
14
10
9
6
4
Others
Molar ratio of reactants
1 : 1
1 : 2
1 : 3
Fig. 4. The influence of the molar ratio of reactants on the yield and composition of the products. Synthesis conditions: 20 wt %
H-Ymmm catalyst, 160°C, the solvent chlorobenzene, 6 h.
5. S. Calus, E. Gondek, A. Danel, et al., Mater. Lett. 61,
of meso- and macropores, and an increase in the con-
centration of acid sites facilitate this process over zeo-
lite catalysts. The conditions found for producing 2-
ethyl-3-methylquinoline 2 over the H-Ymmm zeolite
with the maximum yield are as follows: the aniline :
aldehyde molar ratio of 1 : 2, 20 wt % catalyst, 160°C,
chlorobenzene as the solvent, 6 h.
3292 (2007).
6. V. V. Kouznetsov, L. Y. Mendez, and C. M. Gomez,
Curr. Org. Chem, No. 9, 141 (2005).
7. Y. Watanabe, M. Yamamoto, S. C. Shim, et al., Chem.
Lett., 1025 (1979).
8. J. Lopez-Sanz, E. Perez-Mayoral, D. Prochazkova,
et al., Top. Catal. 53, 1430 (2010).
9. R. Brosius, D. Gammon, F. van Laar, et al., J. Catal.
ACKNOWLEDGMENTS
239, 362 (2006).
10. Q. Guo, L. Liao, W. Teng, et al., Catal. Today 263, 117
The structural studies of compounds 1–3 were per-
formed at the Agidel’ center for shared use of the Institute of
Petroleum Chemistry and Catalysis, Ufa Federal Research
Center, Russian Academy of Sciences.
(2016).
11. A. N. Khazipova, I. N. Pavlova, N. G. Grigor’eva,
et al., Khim. Tekhnol., No. 1, 5 (2012).
12. K. K. Gorshunova, Ahmed Kanaan Ramadan,
O. S. Travkina, et al., Pet. Chem. 54, 132 (2014).
FUNDING
13. B. I. Kutepov, O. S. Travkina, I. N. Pavlova, et al.,
Russ. J. Appl. Chem. 88, 65 (2015).
This work was supported by the Russian Science Foun-
dation and Department of Science and Technology of the
Government of India, grant no. 16-43-02010, and per-
formed in accordance with state task no. AAAA-A17-
117012610058-4.
14. M. R. Agliullin, N. G. Grigor’eva, I. G. Danilova,
et al., Kinet. Catal. 56, 501 (2015).
15. M. R. Agliullin, I. G. Danilova, A. V. Faizullin, et al.,
Microporous Mesoporous Mater. 230, 118 (2016).
16. M. L. Pavlov, O. S. Travkina, A. N. Khazipova, et al.,
Pet Chem. 55, 552 (2015).
17. R. G. Rice and E. J. Kohn, J. Am. Chem. Soc. 77, 4052
REFERENCES
(1955).
1. U. Desai, S. Mitragotri, T. Thopate, et al., Arkivoc 15,
18. Y. Watanabe, S. C. Shim, and T. Mitsudo, Bull. Chem.
198 (2006).
Soc. Jpn. 54, 3460 (1981).
2. S. Bawa, S. Kumar, S. Drabu, and R. Kumar, J. Pharm.
BioAllied Sci., No. 2, 64 (2010).
3. S. Jain, V. Chandra, P. K. Jain, et al., Arab. J. Chem. 9,
19. N. G. Grigor’eva, E. A. Paukshtis, B. I. Kutepov, et al.,
Pet. Chem. 45, 419 (2005).
20. R. I. Khusnutdinov, A. R. Bayguzina, and U. M. Dzhe-
1878 (2016).
milev, J. Organomet. Chem. 768, 75 (2014).
4. E. E. Ebenso, I. B. Obot, and L. C. Murulana, Int. J.
Electrochem. Sci., No. 5, 1574 (2010).
Translated by E. Boltukhina
PETROLEUM CHEMISTRY Vol. 59 No. 7 2019