Home Microwave-assisted synthesis of pyrrolidinone derivatives using 1,1’-butylenebis(3-sulfo-3H-imidazol-1-ium) chloride in ethylene glycol
Article Open Access

Microwave-assisted synthesis of pyrrolidinone derivatives using 1,1’-butylenebis(3-sulfo-3H-imidazol-1-ium) chloride in ethylene glycol

  • Nader Ghaffari Khaligh EMAIL logo , Taraneh Mihankhah , Mohd Rafie Johan and Salam J.J. Titinchi
Published/Copyright: May 18, 2019
Download Article (PDF)
Become an author with De Gruyter Brill
Submit Manuscript Author Information
Green Processing and Synthesis
From the journal Green Processing and Synthesis Volume 8 Issue 1

Abstract

The energy efficiency of the microwave-assisted synthesis of pyrrolidinones was demonstrated using catalytic loading of 1,1’-butylene-bis(3-sulfo-3H-imidazol-1-ium) chloride as a sulfonic acid functionalized ionic liquid in ethylene glycol as green solvent. The effect of electron donating and electron withdrawing groups on aniline derivatives was studied under conventional heating and microwave irradiation. Furthermore, the cation effect of ionic liquids containing sulfonic groups on the catalytic efficiency for the synthesis of ethyl-1-phenyl-2-(4-chlorophenyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyr-role-3-carboxylate was investigated under conventional heat. The experimental results exhibited that there is a relationship between catalytic efficiency and the number of sulfonic groups and imidazolium moieties linked by carbon spacer.

Keywords: microwave-assisted synthesis; pyrrolidinone; sulfonic-functionalized ionic liquid; electronic effect; cation effect

1 Introduction

Microwave irradiation is known as a non-conventional energy source that has been broadly applied in organic synthesis due to important advantages of this technology including spectacular acceleration, higher yield under milder reaction conditions, higher purity of product by reducing unwanted side reactions and the by-products, the reduction in utilization of solvents or reagents, and the reduction of environmental pollution. The effect of microwave irradiation can be supposed a combination of thermal effects viz. heating rate and ‘‘hot spots’’ along with specific effects, medium effects (the selective absorption of radiation by polar chemicals), superheating effect, and reaction mechanism effects. The reader can find excellent reviews microwave-assisted cycloaddition reactions have been reviewed in the literature [1], heterocyclic chemistry [2, 3,], homogeneous and heterogeneous catalysis [4, 5,], medicinal chemistry, drug discovery and combinatorial chemistry [6, 7, 8,], and green chemistry [9]. The controlled microwave-assisted organic synthesis usually needs shorter heating time, simple apparatus setup, which lead to the lowering of the energy costs. In general, this enabling technology is continuing to be an efficient and practical technique in the organic and medicinal chemistry communities [10, 11, 12,].

The task-specific ionic liquids (TSILs) have displayed promising results in a variety of areas including synthesis, catalysis, gas absorption, analysis, electrochemistry, spectroscopy, extracting, and material science due to very diverse, tunable, and designable properties [13, 14, 15,]. The functional groups can be incorporated into either the anion or the cation of the IL and their application efficiency can be studied on the basis of their specific interactions. Immiscibility of ILs with some organic solvents allows the simple separation of the catalysts and the respective products in different phases which lead to avoid the tedious and expensive procedures along with consuming high volumes of volatile, flammable, and toxic solvents [16, 17,].

The 2-pyrrolidinone core is a well-known heterocyclic scaffold which is found in natural products and pharmaceuticals such as piracetam, oxiracetam, aniracetam, nefiracetam, and levetiracetam. They have been interested over the past few years owing to their notable pharmaceutical effects and the promising results in medicinal chemistry, and drug designing [18]. 2-Pyrrolidinone derivatives substituted in position-4 were able to reduce the extracellular glutamate level, therefore effective for the prophylaxis and treatment of a large number of disorders such as stroke [19]. This fascinating scaffold has diverse pharmacological activities including antibacterial, antifungal, anticancer and anticonvulsant [20, 21, 22, 23,]; therefore, many procedures for the preparation of substituted pyrrolidinone have been reported and also their various reactions offer great scope in the field of medicinal chemistry [24, 25, 26, 27, 28, 29, 30,].

The imidazole-based ionic liquids containing SO3H-functionalized have been well-known to exhibit the catalysis activity for the multicomponent reactions [31, 32, 33, 34, 35, 36,]. Herein, we describe the synthesis of the 2-Pyrrolidinone derivatives in the presence of [BBSI]Cl as an efficient catalyst with a focus on the 6th principle of the twelve principles of green chemistry viz: design for energy efficiency. Also, the structure-activity relationship (SAR) of a variety of ionic liquids containing a common anion was studied.

2 Experiment

2.1 General

Unless specified, all chemicals were analytical grade and purchased from Merck, Aldrich, and Fluka Chemical Companies and used without further purification. Products were characterized by their physical constant and FT-IR, NMR and elemental analysis. All the reactions were carried out in the Discover SP microwave synthesizer which was purchased from CEM, Ltd. and the maximum output microwave power is 300 W. The purity determination of the substrates and products or the reaction monitoring were accompanied by TLC using silica gel SIL G/UV 254 plates or GC-MS on an Agilent 6890GC/5973MSD analysis instrument under 70 eV conditions. The FT-IR spectra were recorded on a Perkin Elmer 781 Spectrophotometer using KBr pellets for solid and neat for liquid samples in the range of 4000-400 cm−1. The 1H and 13C NMR spectra were recorded with Bruker Avance III 600 MHz and 400 MHz instruments. Microanalyses were performed on a Perkin- Elmer 240-B microanalyzer. Melting points were recorded on a Büchi B-545 apparatus in open capillary tubes.

2.2 Typical procedure for the synthesis of pyrrolidinones (2a-q) at room temperature

The diethyl acetylenedicarboxylate (2.0 mmol, 340 mg) and [BBSI]Cl catalyst (1.0 mmol%, 9.1 mg) were mixed in 2 mL ethanol. Then, the aromatic aldehyde and primary amine were added and the mixture was stirred at room temperature for 60 min. After the completion of the reaction (monitored by TLC), the crude products were extracted by EtOAc (3 × 10 mL). The extracted organic phases were collected and dried on anhydrous Na2SO4. The solvent was removed by a rotary evaporator. The purification of the product was performed by flash chromatography or recrystallization from hot ethanol. The spectra and physical data of known products were consistent with those previously reported in the literature.

2.3 Typical procedure for the controlled microwave-assisted synthesis of pyrrolidinones (3a-q)

A mixture of the aryl aldehyde (2.0 mmol), arylamine derivatives (2.0 mmol), diethyl acetylenedicarboxylate (2.0 mmol, 340 mg) and [BBSI]Cl catalyst (1.0 mmol%, 9.1 mg) was stirred in 2 mL ethylene glycol in a 10 mL sealed microwave reactor of Discover SP microwave synthesizer. The reaction mixture was subjected to microwave irradiation of 100 W at room temperature for 5 min. After cooling to room temperature, the crude products were extracted by EtOAc (3 × 10 mL) and the extracted organic phases were dried over anhydrous Na2SO4. The solvent was removed by a rotary evaporator. The pure products were obtained by flash chromatography or recrystallized from hot ethanol.

2.4 The spectral data of some known products

Ethyl-1-phenyl-2-(4-chlorophenyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (3a): FT-IR (KBr) νmax = 3300, 1715, 1690, 1660, 1495, 1370, 1310, 1255, 1210, 1135, 760, 520 cm−1; 1H NMR (400 MHz, CDCl3) δ = 1.20 (t, J =7.0 Hz, 3H), 4.20 (q, J = 7.0 Hz, 2H), 5.72 (s, 1H), 7.11-7.17 (m, 3H), 7.22-7.30 (m, 4H), 7.43 (d, J = 8.0 Hz, 2H), 9.04 (br s, 1H) ppm; 13C NMR (100 MHz, CDCl3) δ = 13.6, 60.5, 61.1, 112.5, 122.0, 125.8, 128.6, 128.7, 128.9, 133.4, 134.1, 135.8, 156.3, 162.4, 164.6 ppm; Anal. Calcd. for C19H16ClNO4: C, 63.78; H, 4.51; N, 3.91; Found: C, 63.73; H, 4.49; N, 3.86%.

Ethyl-1-phenyl-4-hydroxy-5-oxo-2-(4-trifluoromethylphenyl)-2,5-dihydro-1H-pyrrole-3-carboxylate (3d): FT-IR (KBr) νmax = 3300, 2985, 1725, 1690, 1595, 1500, 1445, 1425, 1375, 1330, 1260, 1165, 1120, 1020 cm−1; 1H NMR (400 MHz, CDCl3) δ = 1.19 (t, J = 7.2 Hz, 3H), 4.20 (q, J = 7.2 Hz, 2H), 5.81 (s, 1H), 7.12 (t, J = 7.6 Hz, 1H), 7.30 (t, J = 7.6 Hz, 2H), 7.38 (d, J = 8.0 Hz, 2H), 7.47 (d, J = 8.0 Hz, 2H), 7.53 (d, J = 8.0, 2H), 9.10 (br s, 1H); 13C NMR (150 MHz, CDCl3) δ = 14.2, 60.2, 60.4, 112.0, 122.7, 124.3 (JC–F = 244.7 Hz),, 125.5, 125.7, 125.9, 128.4, 128.7, 129.0, 129.1, 129.2, 136.4, 142.0, 152.5, 162.3, 164.2 ppm; Anal. Calcd. for C20H16F3NO4: C, 61.38; H, 4.12; N, 3.58; Found: C, 61.42; H, 4.16; N, 3.53%.

Ethyl-1-(4-nitrophenyl)-4-hydroxy-5-oxo-2-(4-trifluoromethylphenyl)-2,5-dihydro-1H-pyrrole-3-carboxylate (3o): FT-IR (KBr) νmax = 3320, 2995, 1740, 1690, 1600, 1515, 1450, 1425, 1365, 1330, 1265, 1220, 1190, 1165, 1120, 1070, 1020 cm−1; 1H NMR (600 MHz, CDCl3) δ = 1.22 (t, J = 7.2 Hz, 3H), 4.23 (q, J = 7.2 Hz, 2H), 5.88 (s, 1H), 7.40 (d, J = 8.0 Hz, 2H), 7.57 (d, J = 8.0 Hz, 2H), 7.76 (d, J = 9.2 Hz, 2H), 8.14 (d, J = 9.2 Hz, 2H) ppm; 13C NMR (150 MHz, CDCl3) δ = 14.0, 60.5, 61.9, 113.5, 120.6, 123.5 (JC–F = 265.0 Hz), 126.0, 126.1, 127.8, 130.9, 131.2, 131.5, 138.7, 141.6, 144.4, 155.8, 163.0, 164.5 ppm; Anal. Calcd. for C20H15F3N2O6: C, 55.05; H, 3.46; N, 6.42; Found: C, 55.03; H, 3.42; N, 6.38%.

Ethyl-1-p-tolyl-4-hydroxy-5-oxo-2-(4-trifluoromethylphenyl)-2,5-dihydro-1H-pyrrole-3-carboxylate (3p): FT-IR (KBr) νmax = 3305, 2985, 1730, 1690, 1660, 1515, 1445, 1420, 1370, 1325, 1255, 1215, 1170, 1145, 1110, 1065, 1020 cm−1; 1H NMR (400 MHz, CDCl3) δ = 1.19 (t, J = 7.2 Hz, 3H), 2.26 (s, 3H), 4.20 (q, J = 7.2 Hz, 2H), 5.77 (s, 1H), 7.09 (d, J = 8.4 Hz, 2H), 7.34 (d, J = 8.4 Hz, 2H), 7.37 (d, J = 8.0 Hz, 2H), 7.53 (d, J = 8.0 Hz, 2H), 9.11 (br s, 1H) ppm; 13C NMR (100 MHz, CDCl3) δ = 13.8, 20.7, 61.0, 61.2, 112.3, 122.1, 123.8 (JC–F = 270.8 Hz), 125.5, 125.6, 125.7, 127.9, 129.5, 130.0, 130.4, 130.8, 133.2, 136.0, 139.5, 156.6, 162.5, 164.6 ppm; Anal. Calcd. for C21H18F3NO4: C, 62.22; H, 4.48; N, 3.46; Found: C, 62.19; H, 4.42; N, 3.38%.

Ethyl-1-(4-methoxyphenyl)-4-hydroxy-5-oxo-2-(4-trifluoromethylphenyl)-2,5-dihydro-1H-pyrrole-3-carboxylate (3q): FT-IR (KBr) νmax = 3300, 1715, 1690, 1660, 1495, 1370, 1310, 1255, 1210, 1135, 760, 520 cm−1; 1H NMR (400 MHz, CDCl3) δ = 1.14 (t, J = 7.2 Hz, 3H), 3.69 (s, 3H), 4.15 (q, J = 7.2 Hz, 2H), 5.72 (s, 1H), 6.77 (d, J = 9.2 Hz, 2H), 7.28 (t, J = 9.2 Hz, 2H), 7.33 (d, J = 8.4 Hz, 2H), 7.50 (d, J = 8.4 Hz, 2H) ppm; 13C NMR (100 MHz, CDCl3) δ = 14.4, 55.6, 60.2, 61.0, 111.8, 114.4, 124.0 (JC–F =269 Hz), 125.5, 125.6, 125.8, 128.4, 128.5, 128.7, 129.0, 129.2, 129.3, 142.2, 153.8, 157.4, 162.4, 164.2 ppm; Anal. Calcd. for C21H18F3NO5: C, 59.86; H, 4.31; N, 3.32; Found: C, 58.82; H, 4.25; N, 3.29%.

3 Results and discussion

In order to study and achieve the optimized reaction conditions, the 4-chlorobenzaldehyde, aniline, and diethyl acetylenedicarboxylate were chosen as the model reactants and their one-pot reaction was studied at room temperature in the absence of catalyst and under solvent free conditions. The model reaction was conducted by the planetary ball mill which afforded the corresponding product in trace yield after 4 h at room temperature (Table 1, entry 1). In the presence of water as green solvent, ethyl-1-phenyl-2-(4-chlorophenyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (3a) was afforded in 20% yield in catalyst-free condition (Table 1 entry 2). An improvement was displayed when the reaction was conducted in ethanol because the model reactants were more soluble in ethanol than in water (Table 1, entry 3). When 0.5 mol% of [BBSI]Cl was added to the model reaction in ethanol and the mixture was stirred for 2 h at room temperature, 3a afforded in 79% yield (Table 1, entry 4). Increasing amount of catalyst led to a significant improvement in yield (Table 1, entry 5) while further reduction of the reaction time afforded a lower yield of 3a (Table 1, entries 6 and 7).

Table 1

Optimization of the synthesis of ethyl-1-phenyl-2-(4-chlorophenyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (3a) under a variety of reaction conditions.a

EntryLoading of [BBSI]Cl (mol%)Solvent (2 mL)Reaction time (h)Yield (%)b
10.0–4Tracec
20.0H2O420
30.0EtOH (96%)426
40.5EtOH (96%)279
51.0EtOH (96%)189
61.0EtOH (96%)3088
71.0EtOH (96%)20 min70

  1. a Reaction conditions: 4-chlorobenzaldehyde (1a) (2.0 mmol), aniline (2.0 mmol), diethyl acetylenedicarboxylate (2.0 mmol), room temperature.

    b Isolated yield.

    c Monitored by GC-MS.

Table 2

Optimization of the synthesis of ethyl-1-phenyl-2-(4-chlorophenyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (2a) under microwave irradiation.a

EntryLoading of [BBSI]Cl (mol%)Solvent (2 mL)MW (W)Temp. (°C)Reaction time (min)Yield (%)b
11.0EtOH (96%)–r.t.3088
21.0EtOH (96%)100r.t.1592
30.5EtOH (96%)100r.t.1591
40.5Ethylene glycol100r.t.591
50.5Ethylene glycol150r.t.592
60.5Ethylene glycol300r.t.585
70.5Ethylene glycol10050591

  1. a Reaction conditions: 4-chlorobenzaldehyde (1a) (2.0 mmol), aniline (2.0 mmol), diethyl acetylenedicarboxylate (2.0 mmol).

    b Isolated yield.

To the best of our knowledge, no report exists concerning the use of sulfonic acid functionalized ionic liquid in a green solvent for the controlled microwave-assisted synthesis of pyrrolidinones; therefore, the model reaction was performed under microwave irradiation in ethanol at room temperature (Table 2, entries 1-3). A higher yield was obtained under microwave irradiation within a very shorter reaction time as it was expected (Table 2, entry 2) [37, 38,]. The 3a was obtained in 91% yield when amount of catalyst was decreased to 0.5 mol% of [BBSI] Cl (Table 2, entry 3). In general, polar solvents and ionic compounds are appropriate solvents for the microwave-assisted reactions [39]. Ethylene glycol exhibits a low vapor pressure and as a polar solvent thereby enhance its suitability for microwave heating. A significant improvement was obtained in the reaction time when ethylene glycol was used as a solvent (Table 2, entry 4). Increasing the power of microwave irradiation led to a drop in the yield of 3a (Table 2, entries 5 and 6), while we observed no improvement in 3a yield within a longer reaction time (Table 2, entry 7).

It is supposed that the improvements in yield and an increase in the reaction rate is related to the peculiarities of the substance heating under microwave exposure, which lies in the rapid and uniform heating of the whole reaction mixture. The heat generated in their volume is a result of direct interaction of electromagnetic irradiation with the reactants, ionic liquid, and solvent. Therefore microwave heating is an effective tool for promoting the multi-component reactions and using energy more efficiently.

Then, a variety of aldehydes 1(a-q) and amines were investigated under optimized conditions for both methods viz. conventional (A) and non-conventional (B) processes and as shown in Table 3, the substituted pyrrolidinones (3a-m) were afforded in good to excellent yield (Scheme 1). The electron-withdrawing substituents on aromatic ring of aryl aldehydes afforded higher yields of pyrrolidinones than electron-donating substituents at

Scheme 1 Synthesis of pyrrolidinone derivatives in the presence of [BBSI]Cl under optimal conditions.
Scheme 1

Synthesis of pyrrolidinone derivatives in the presence of [BBSI]Cl under optimal conditions.

Table 3

Synthesis of 2-pyrrolidinones in the presence of [BBSI]Cl under optimized reaction conditions.a

EntryAldehyde (1)amine (2)Product (3)Yield (%)bMelting point (°C)
Method AMethod BFoundReported (ref.)
14-Cl-C6H4-C6H5-NH2a8891188-190190-192 (40)
2C 6H5-C6H5-NH2b8690174-176174-176 (40)
34-CH3-C6H4-C6H5-NH2c8488180-182179-181 (42)
44-CF3-C6H4-C6H5-NH2d9497170-172172-174 (41)
54-CH3O-C6H4-C6H5-NH2e8290140-142138-140 (40)
62-CH3O-C6H4-C6H5-NH2f7784190-192193-195 (41)
74-HO-C6H4-C6H5-NH2g8190240-242243-245 (42)
84-NO2-C6H4-C6H5-NH2h9697180-182181-183 (42)
92-NO2-C6H5-C6H5-NH2i9195175-177178-180 (41)
102-Cl-C6H4-C6H5-NH2j8290200-202204-207 (42)
114-Br-C6H4-C6H5-NH2k8893190-192190-193 (42)
12C6H5-C6H5-NH2l8190190-191190-192 (40)
133,4(OCH2O)C6H3-C6H5-CH2-NH2m8490170-172170-172 (40)
144-[(CH3)2N]-C6H4-C6H5-NH2n––––
154-CF3-C6H4-4-NO2-C6H4-o52c88170-172175-177 (41)
164-CF3-C6H4-4-CH3-C6H4-p8292172-173176-178 (41)
174-CF3-C6H4-4-CH3O-C6H4-q8392165-167162-164 (41)

  1. a Reaction conditions for method A: aryl aldehyde (1) (2.0 mmol), aniline (2.0 mmol), diethyl acetylenedicarboxylate (2.0 mmol), [BBSI]Cl (1.0 mol%), ethanol (96%) (2 mL), temperature (reflux), room temperature, reaction time (30 min).

    Reaction conditions for method B: aryl aldehyde (1) (2.0 mmol), aniline (2.0 mmol), diethyl acetylenedicarboxylate (2.0 mmol), [BBSI]Cl (1.0 mol%), ethylene glycol (2 mL), microwave power (100 W), room temperature, reaction time (5 min).

    bIsolated yield.

    cReaction time (240 min).

the same position (Table 3, entries 4 and 8 vs. 5) probably because the electrophilic property of aryl aldehyde increase [43]. No decomposition and isomerization were observed when the acid sensitive aldehydes were treated with aniline and diethyl acetylenedicarboxylate under optimal conditions (Table 3, entries 5 and 13). A few spots along with aryl aldehyde spot was observed on TLC when 4-(dimethylamino)-benzaldehyde (1n) was utilized as aryl aldehyde under optimized conditions in both method A and B and the corresponding product was not isolated (Table 3, entry 14) which may be owing to deactivation of 1nvia resonance stabilization in the presence of [BBSI]Cl (Scheme 2).

Scheme 2 Plausible deactivation of 4-(dimethylamino) benzaldehyde for the imine (Schiff base) formation in the presence of [BBSI]Cl under optimized reaction conditions.
Scheme 2

Plausible deactivation of 4-(dimethylamino) benzaldehyde for the imine (Schiff base) formation in the presence of [BBSI]Cl under optimized reaction conditions.

The effect of electron-donating and electron-withdrawing substituents in para-position of aniline derivatives were studied for the reaction 4-triflourobenzaldeyde, diethyl acetylenedicarboxylate, and Furthermore, A variety of aryl amines containing electron-donating and electron-withdrawing substituents reacted with 4-trifluoro benzaldehyde and diethyl acetylenedicarboxylate through method A and

B under optimal conditions (Table 3, entries 15-17). The results demonstrated that the electron-withdrawing groups deactivated amino group and led to decrease the product yield and the reaction rate (Table 4, entry 15), while the electron-donating groups activated amino group and afforded a high yield of the corresponding products under optimal reaction conditions (Table 4, entries 16 and 17).

Table 4

The comparative study of present vs. previously reported methodology for the synthesis of ethyl-1,2-diphenyl-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (2b).

EntryCatalystCatalyst loading (mol%)SolventTemp. (°C)Reaction time (h)Yield (%)RecyclableRef.
1––Ethanol/H2O (1:1 v/v)r.t.1587–46
2Citric acid mono hydrate200Ethanolr.t.1085No42
3Citric acid mono hydrate200Ethanol40 (US, 100 W)b20 min90No42
4p-toluenesulfonic acid20Ethanolr.t.4862No29
5Lactic acid1140 (1mL)Lactic acid (85% wt/wt)30260aNo41
6Glacial acetic acid1746 (1 mL)Glacial acetic acid30224aNo41
7[BBSI]Cl1.0Ethanol (96%)r.t.30 min86YesThis work
8[BBSI]Cl0.5Ethylene glycolr.t. (MW, 100 W)c5 min90YesThis work

  1. a 4-methylbenzaldehyde

    b Ultrasound irradiation (power 100 W)

    c Microwave irradiation (power 100 W)

A possible mechanism is shown in Scheme 3. In the first step, the carbonyl group of aldehyde is activated by C-2 hydrogen atom of imidazole moieties and the acidic hydrogen of sulfonic groups of [BBSI]Cl through the formation of hydrogen bond. As shown in Scheme 3, the [BBSI]Cl can probably act as dehydrating agents which will facilitate the formation of imine (I) from the reaction of as-activated aryl aldehyde and arylamine [44, 45,]. The addition reaction of water and diethyl acetylenedicarboxylate forms the intermediate

Scheme 3 The proposed mechanism for the synthesis of pyrrolidinone derivatives in the presence of [BBSI]Cl.
Scheme 3

The proposed mechanism for the synthesis of pyrrolidinone derivatives in the presence of [BBSI]Cl.

(II) followed by a Micheal addition of imine (I) and intermediate (II) which led to forming intermediate (III). An intermolecular cyclization and elimination of ethanol molecule afford the final product.

Finally, a 2.0 g scale of the model reactants was performed in the presence of 0.2 mmol of [BBSI]Cl in 20 mL of ethanol and ethylene glycol for method A and B, respectively; and 3a was isolated in 82% and 86% yield after 1.5 h and 10 min.

Table 4 showed a comparison of present and reported methods in the literature. As observed, the catalytic efficiency of [BBIS]Cl is superior to the reported solvent-catalysts in terms of catalyst loading, product yields, reaction times and recyclability (Table 4).

As shown in Table 5, the structure of the cationic moiety plays a crucial role on the catalytic efficiency of the ILs derived from pyrazinium, piperazinium, benzimidazolium, imidazolium cation containing chloride as counter anion as previously reported [46]. The [BBSI]Cl showed the best result comparing to pyrazinium and piperazinium ILs while the [PiS]Cl and [PzS]Cl exhibited a moderate catalytic activity which can be assigned to the presence of two sulfonic groups per IL molecules. Based on the catalytic efficiency of [PzPS]Cl and [PzS]Cl, it seems that carbon spacer can be also considered as an important parameter on the catalytic efficiency of ILs (Table 5, entries 2 and 3). In general, it seems that the presence and number of the C-2 hydrogen and acid sites per imidazole-based IL, as well as the carbon spacer between the imidazolium moieties, increased their catalytic efficiency (Table 5, entries 4-6).

Table 5

Comparison of result obtained for the synthesis of ethyl-1-phenyl-2-(4-chlorophenyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylate (3a) in the presence of some sulfonic-functionalized ionic liquid containing mono- and di- cationic nucleus with [BBSI]Cl.a

EntryIL as solvent-catalystAbbreviationYield (%)
1[PiS]Cl66
2[PzS]Cl61
3[PzPS]Cl72
4[DSI]Cl77
5[DSBI]Cl80
6[BBSI]Cl89

  1. a Reaction conditions: 4-chlorobenzaldehyde (1a) (2.0 mmol), aniline (2.0 mmol), diethyl acetylenedicarboxylate (2.0 mmol), ionic liquid containing sulfonic acid (1.0 mol% mL), ethanol (96%, 2 mL), room temperature, reaction time (30 min).

    [PiS]Cl = Sulfonic acid-functionalized piperizanium chloride, [PzS] Cl = Sulfonic acid-functionalized pyrazinium chloride, [PzPS]Cl = Sulfonic acid-functionalized pyrazinium propyl chloride, [DSI]Cl = Sulfonic acid-functionalized imidazolium chloride.

Recycling and reusability of the TSILs are very important for economic and environmental reasons when it comes to large-scale applications. After completion of the reaction, the solvent was removed in vacuum and the desired pyrrolidinones were readily extracted using EtOAc. The residue was recharged with new model reactants for the next run. The desired product was afforded in an average 82% and 86% yield for three successive runs in method A and B, respectively. The recycled [BBSI]Cl exhibited almost a constant catalytic activity even after three sequential runs. Furthermore, the 1H NMR analysis of recycled [BBSI]Cl showed no considerable change under the present workup after the third run (Figures 1 and 2).

Figure 1 1H NMR of [BBSI]Cl after the second run of the reaction under optimized reaction conditions.
Figure 1

1H NMR of [BBSI]Cl after the second run of the reaction under optimized reaction conditions.

Figure 2 1H NMR of [BBSI]Cl after the third run of the reaction under optimized reaction conditions.
Figure 2

1H NMR of [BBSI]Cl after the third run of the reaction under optimized reaction conditions.

4 Conclusion

In summary, the catalytic efficiency of [BBSI]Cl and the energy efficiency of microwave irradiation were approved for the synthesis of pyrrolidinone derivatives. The advantages of current protocol included simple experimental and sustainable procedure, high reaction rate, good to excellent yield, and recyclability of the

ionic liquid. Its application for the one-pot multi components reaction has highlighted the importance of task-specific ionic liquids (TSILs) as efficient catalyst and microwave irradiation as a green energy in organic synthesis, and we hope that the present method will find applications in academic and industrial processes owing to its broad substrate scope, improved yields, time saver, energy efficiency, and environmentally friendly transformation.

and also , Tel.: +98-21-6643-1738; Fax: +98-21-6693-4046

Acknowledgements

This work was supported by NANOCAT RU-Geran (Project no. RU001-2018) for Scientific Research from the University of Malaya, Malaysia. The authors are grateful to staff members in the Analytical and Testing Center of Iran University of Science and Technology for partial support.

References

[1] de la Hoz A., Díaz-Ortiz A., Moreno A., Langa F., Cycloadditions under microwave irradiation conditions: Methods and applications. Eur. J. Org. Chem., 2000, 4, 3659-3673.10.1002/1099-0690(200011)2000:22<3659::AID-EJOC3659>3.0.CO;2-0Search in Google Scholar

[2] Xu Y., Guo Q.X., Syntheses of heterocyclic compounds under microwave irradiation. Heterocycles, 2004, 63, 903-974.10.1002/chin.200424266Search in Google Scholar

[3] Romanova N.N., Kudan P.V., Gravis A.G., Bundel Y.G., The use of microwave activation in the chemistry of heterocyclic compounds. (Review). Chem. Heterocycl. Compd., 2000, 36, 1130-1140.10.1023/A:1002898029145Search in Google Scholar

[4] Larhed M., Moberg C., Hallberg A., Microwave-accelerated homogeneous catalysis in organic chemistry. Acc. Chem. Res., 2002, 35, 717-727.10.1021/ar010074vSearch in Google Scholar

[5] Will H., Scholz P., Ondruschka B., Heterogene Gasphasenkatalyse im Mikrowellenfeld. Chem. Ing. Tech., 2002, 74, 1057-1067.10.1002/1522-2640(20020815)74:8<1057::AID-CITE1057>3.0.CO;2-3Search in Google Scholar

[6] Lew A., Krutzik P.O., Hart M.E., Chamberlin A.R., Increasing rates of reaction: microwave-assisted organic synthesis for combinatorial chemistry. J. Comb. Chem., 2002, 4, 95-105.10.1021/cc010048oSearch in Google Scholar

[7] Wathey B, Tierney J, Lidström P, Westman J., The impact of microwave-assisted organic chemistry on drug discovery. Drug Discov. Today, 2002, 7, 373-380.10.1016/S1359-6446(02)02178-5Search in Google Scholar

[8] Blackwell H.E., Out of the oil bath and into the oven–microwave-assisted combinatorial chemistry heats up. Org. Biomol. Chem., 2003, 1, 1251-1255.10.1039/b301432kSearch in Google Scholar

[9] Varma R.S., In Advances in green chemistry: Chemical syntheses using microwave irradiation. Astra Zeneca Research Foundation, Kavitha Printers, Bangalore, India, 2002, 35-38.Search in Google Scholar

[10] Kappe C.O., Stadler A., Microwaves in Organic and Medicinal Chemistry. Wiley-VCH, Weinheim, 2005.10.1002/3527606556Search in Google Scholar

[11] Colombo M., Peretto I., Chemistry strategies in early drug discovery: an overview of recent trends. Drug Discov. Today, 2008, 13, 677-684.10.1016/j.drudis.2008.03.007Search in Google Scholar

[12] Santagada V., Frecentese F., Perissutti E., Fiorino F., Severino B., Caliendo G., Microwave assisted synthesis: A new technology in drug discovery. Mini-Rev. Med. Chem., 2009, 9, 340-358.10.2174/1389557510909030340Search in Google Scholar PubMed

[13] Amarasekara A.S., Acidic ionic liquids. Chem. Rev., 2016, 116, 6133-6183.10.1021/acs.chemrev.5b00763Search in Google Scholar PubMed

[14] Giernoth R., Task-specific ionic liquids. Angew. Chem. Int. Ed., 2010, 49, 2834-2839.10.1002/anie.200905981Search in Google Scholar PubMed

[15] Sun X., Luo H., Dai S., Ionic liquids-based extraction: A promising strategy for the advanced nuclear fuel cycle. Chem. Rev., 2012, 112, 2100-2128.10.1021/cr200193xSearch in Google Scholar PubMed

[16] Sawant A.D., Raut D.G., Darvatkar N.B., Salunkhe M.M., Recent developments of task-specific ionic liquids in organic synthesis. Green Chem. Lett. Rev., 2011, 4, 41-54.10.1080/17518253.2010.500622Search in Google Scholar

[17] Qureshi Z.S., Deshmukh K.M., Bhanage B.M., Clean technologies and environmental policy. Clean Technol. Envir., 2014, 16, 1487-1513.10.1007/s10098-013-0660-0Search in Google Scholar

[18] Hosseinzadeh Z., Ramazani A., Hosseinzadeh K., Razzaghi-Asl N., Gouranlou F., An overview on chemistry and biological importance of pyrrolidinone. Current Org. Syn., 2018, 15, 166-178.10.2174/1570179414666170908165445Search in Google Scholar

[19] Feuerstein T.J., Knoerle R., Position-4 substituted 2-pyrrolidinone derivatives to reduce the level of extracellular glutamate. 2002, Patent US 6,384,069 B1.Search in Google Scholar

[20] Geng Y., Wang X., Yang L., Sun H., Wang Y., Zhao Y., et al., Antitumor activity of a 5-hydroxy-1H-Pyrrol-2-(5H)-one-based synthetic small molecule in vitro and in vivo PLoS One, 2015, 10, 1-15.10.1371/journal.pone.0128928Search in Google Scholar PubMed PubMed Central

[21] Ma K., Wang P., Fu W., Wan X., Zhou L., Chu Y., et al., Rational design of 2-pyrrolinones as inhibitors of HIV-1 integrase. Bioorg. Med. Chem. Lett., 2011, 21, 6724-6727.10.1016/j.bmcl.2011.09.054Search in Google Scholar PubMed

[22] Pendri A., Troyer T.L., Sofia M.J., Walker M.A., Naidu B.N., Banville J., et al., Solid phase synthesis of novel pyrrolidinedione analogs as potent HIV-1 integrase inhibitors. J. Comb. Chem., 2010, 12, 84-90.10.1021/cc9001026Search in Google Scholar PubMed

[23] Gein V.L., Armisheva M.N., Rassudikhina N.A., Vakhrin M.I., Voronina E.V., Synthesis and antimicrobial activity of 1-(4-hydroxyphenyl)-4-acyl-5-aryl-3-hydroxy-3-pyrrolin-2-ones. Pharm. Chem. J., 2011, 45, 162-164.10.1007/s11094-011-0584-0Search in Google Scholar

[24] Franco M.S.F., Casagrande G.A., Raminelli C., Moura S., Rossatto M., Quina F.H., et al., Ultrasound-promoted environmentally friendly synthesis of 5-(3,3,3-trifluoro-2-oxopropylidene) pyrrolidin-2-ones. Synth. Commun., 2015, 45, 692-701.10.1080/00397911.2014.978504Search in Google Scholar

[25] Choi D.R., Lee K.Y., Chung Y.S., Joo J.E., Kim Y.H., Oh C.Y., et al., Diastereoselective synthesis of polysubstituted pyrrolidinone as a key intermediate for the anticancer agents by palladium(II)-catalyzed carboxylation. Arch. Pharm. Res., 2005, 28, 151-158.10.1007/BF02977706Search in Google Scholar PubMed

[26] Overman L.E., Remarchuk T.P., Catalytic asymmetric intramolecular aminopalladation: Enantioselective synthesis of vinyl-substituted 2-oxazolidinones, 2-imidazolidinones, and 2-pyrrolidinones. J. Am. Chem. Soc., 2002, 124, 12-13.10.1021/ja017198nSearch in Google Scholar PubMed

[27] Singh V., Saxena R., Batra S., Simple and efficient synthesis of substituted 2-pyrrolidinones, 2-pyrrolones, and pyrrolidines from enaminones of Baylis−Hillman derivatives of 3-isoxazolecarbaldehydes. J. Org. Chem., 2005, 70, 353-356.10.1021/jo048411bSearch in Google Scholar PubMed

[28] Sarkar R., Mukhopadhyay C., Admicellar catalysis in multicomponent synthesis of polysubstituted pyrrolidinones. Tetrahedron Lett., 2013, 54, 3706-3711.10.1016/j.tetlet.2013.05.017Search in Google Scholar

[29] Sun J., Wu Q., Xia E.Y., Yan C.G., Molecular diversity of three‐ component reactions of aromatic aldehydes, arylamines, and acetylenedicarboxylates. Eur. J. Org. Chem., 2011, 2011, 2981-2986.10.1002/ejoc.201100008Search in Google Scholar

[30] Zhu Q., Jiang H., Li J., Liu S., Xia C., Zhang M., Concise and versatile multicomponent synthesis of multisubstituted polyfunctional dihydropyrroles. J. Comb. Chem., 2009, 11, 685-696.10.1021/cc900046fSearch in Google Scholar PubMed

[31] Khaligh N.G., 4-(Succinimido)-1-butane sulfonic acid as a Brönsted acid catalyst for synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions. Chin. Chem. Lett., 2015, 26, 26-30.10.1016/j.cclet.2014.10.009Search in Google Scholar

[32] Khaligh N.G., Abd Hamid S.B., Titinchi S.J.J., Succinimide-N-sulfonic acid as a recyclable Brönsted acid catalyst for synthesis of pyrano[4,3-b]pyran derivatives by using solar energy under solvent-free conditions. Polycycl. Arom. Comp., 2017, 37, 31-38.10.1080/10406638.2015.1076010Search in Google Scholar

[33] Khaligh N.G., 1,1′-butylenebis(3-methyl-3H-imidazol-1-ium) hydrogen sulfate catalyzed one-pot multi-component synthesis of unsymmetrical polyhydroquinoline derivatives. Polycycl. Arom. Comp., 2016, 36, 284-294.10.1080/10406638.2014.980432Search in Google Scholar

[34] Khaligh N.G., Synthesis and characterization of novel binuclear task-specific ionic liquid: an efficient and sustainable sulfonic-functionalized ionic liquid for one-pot synthesis of xanthenes. Res. Chem. Intermed., 2018, 44, 4045-4062.10.1007/s11164-018-3354-8Search in Google Scholar

[35] Khaligh N.G., Mihankhah T., Johan M.R., Ching J.J., Two novel binuclear sulfonic-functionalized ionic liquids: Influence of anion and carbon-spacer on catalytic efficiency for one-pot synthesis of bis(indolyl)methanes. J. Mol. Liq., 2018, 259, 260-273.10.1016/j.molliq.2018.03.044Search in Google Scholar

[36] Strauss C.R., Rooney D.W., Accounting for clean, fast and high yielding reactions under microwave conditions. Green Chem., 2010, 12, 1340-1344.10.1039/c0gc00024hSearch in Google Scholar

[37] Kappe C.O., Microwave dielectric heating in synthetic organic chemistry. Chem. Soc. Rev., 2008, 37, 1127-1139.10.1039/b803001bSearch in Google Scholar

[38] Lidström P., Tierney J., Wathey B., Wetman J., Microwave assisted organic synthesis–A review. Tetrahedron, 2001, 57, 9225-9283.10.1016/S0040-4020(01)00906-1Search in Google Scholar

[39] Castellano T.G., Neo A.G., Marcaccini S., Marcos C.F., Enols as feasible acid components in the Ugi condensation. Org. Lett., 2012, 14, 6218-6221.10.1021/ol302976gSearch in Google Scholar PubMed

[40] Yang J., Tan J.N., Gu Y., Lactic acid as an invaluable bio-based solvent for organic reactions. Green Chem., 2012, 14, 3304-3317.10.1039/c2gc36083gSearch in Google Scholar

[41] Ahankar H., Ramazani A., Ślepokura K., Lis T., Joo S.W., Synthesis of pyrrolidinone derivatives from aniline, an aldehyde and diethyl acetylenedicarboxylate in an ethanolic citric acid solution under ultrasound irradiation. Green Chem., 2016, 18, 3582-3593.10.1039/C6GC00157BSearch in Google Scholar

[42] Connors K.A., Structure Reactivity Relationships: the Study of reaction rates in solution (Chapter 7). VCH Publishers, New York, 1990, p 311.Search in Google Scholar

[43] Flores A.C., Flores E.A., Hernández E., Castro L.V., García A., Alvarez F., et al., Anion and cation effects of ionic liquids and ammonium salts evaluated as dehydrating agents for super-heavy crude oil: Experimental and theoretical points of view. J. Mol. Liq., 2014, 196, 249-257.10.1016/j.molliq.2014.03.044Search in Google Scholar

[44] Krannich M., Heym F., Jess A., Characterization of six hygroscopic ionic liquids with regard to their suitability for gas dehydration: Density, viscosity, thermal and oxidative Stability, vapor pressure, diffusion coefficient, and activity coefficient of water. J. Chem. Eng. Data, 2016, 61, 1162-1176.10.1021/acs.jced.5b00806Search in Google Scholar

[45] Zonouz A.M., Eskandari I., Notash B., Efficient synthesis of 3-pyrrolin-2-one derivatives in aqueous media. Synth. Commun., 2015, 45, 2115-2121.10.1080/00397911.2015.1065506Search in Google Scholar

Received: 2018-05-25
Accepted: 2018-09-21
Published Online: 2019-05-18
Published in Print: 2019-01-28

© 2019 N.G. Khaligh et al., published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 Public License.

Articles in the same Issue

  1. Regular Articles
  2. Studies on the preparation and properties of biodegradable polyester from soybean oil
  3. Flow-mode biodiesel production from palm oil using a pressurized microwave reactor
  4. Reduction of free fatty acids in waste oil for biodiesel production by glycerolysis: investigation and optimization of process parameters
  5. Saccharin: a cheap and mild acidic agent for the synthesis of azo dyes via telescoped dediazotization
  6. Optimization of lipase-catalyzed synthesis of polyethylene glycol stearate in a solvent-free system
  7. Green synthesis of iron oxide nanoparticles using Platanus orientalis leaf extract for antifungal activity
  8. Ultrasound assisted chemical activation of peanut husk for copper removal
  9. Room temperature silanization of Fe3O4 for the preparation of phenyl functionalized magnetic adsorbent for dispersive solid phase extraction for the extraction of phthalates in water
  10. Evaluation of the saponin green extraction from Ziziphus spina-christi leaves using hydrothermal, microwave and Bain-Marie water bath heating methods
  11. Oxidation of dibenzothiophene using the heterogeneous catalyst of tungsten-based carbon nanotubes
  12. Calcined sodium silicate as an efficient and benign heterogeneous catalyst for the transesterification of natural lecithin to L-α-glycerophosphocholine
  13. Synergistic effect between CO2 and H2O2 on ethylbenzene oxidation catalyzed by carbon supported heteropolyanion catalysts
  14. Hydrocyanation of 2-arylmethyleneindan-1,3-diones using potassium hexacyanoferrate(II) as a nontoxic cyanating agent
  15. Green synthesis of hydratropic aldehyde from α-methylstyrene catalyzed by Al2O3-supported metal phthalocyanines
  16. Environmentally benign chemical recycling of polycarbonate wastes: comparison of micro- and nano-TiO2 solid support efficiencies
  17. Medicago polymorpha-mediated antibacterial silver nanoparticles in the reduction of methyl orange
  18. Production of value-added chemicals from esterification of waste glycerol over MCM-41 supported catalysts
  19. Green synthesis of zerovalent copper nanoparticles for efficient reduction of toxic azo dyes congo red and methyl orange
  20. Optimization of the biological synthesis of silver nanoparticles using Penicillium oxalicum GRS-1 and their antimicrobial effects against common food-borne pathogens
  21. Optimization of submerged fermentation conditions to overproduce bioethanol using two industrial and traditional Saccharomyces cerevisiae strains
  22. Extraction of In3+ and Fe3+ from sulfate solutions by using a 3D-printed “Y”-shaped microreactor
  23. Foliar-mediated Ag:ZnO nanophotocatalysts: green synthesis, characterization, pollutants degradation, and in vitro biocidal activity
  24. Green cyclic acetals production by glycerol etherification reaction with benzaldehyde using cationic acidic resin
  25. Biosynthesis, characterization and antimicrobial activities assessment of fabricated selenium nanoparticles using Pelargonium zonale leaf extract
  26. Synthesis of high surface area magnesia by using walnut shell as a template
  27. Controllable biosynthesis of silver nanoparticles using actinobacterial strains
  28. Green vegetation: a promising source of color dyes
  29. Mechano-chemical synthesis of ammonia and acetic acid from inorganic materials in water
  30. Green synthesis and structural characterization of novel N1-substituted 3,4-dihydropyrimidin-2(1H)-ones
  31. Biodiesel production from cotton oil using heterogeneous CaO catalysts from eggshells prepared at different calcination temperatures
  32. Regeneration of spent mercury catalyst for the treatment of dye wastewater by the microwave and ultrasonic spray-assisted method
  33. Green synthesis of the innovative super paramagnetic nanoparticles from the leaves extract of Fraxinus chinensis Roxb and their application for the decolourisation of toxic dyes
  34. Biogenic ZnO nanoparticles: a study of blueshift of optical band gap and photocatalytic degradation of reactive yellow 186 dye under direct sunlight
  35. Leached compounds from the extracts of pomegranate peel, green coconut shell, and karuvelam wood for the removal of hexavalent chromium
  36. Enhancement of molecular weight reduction of natural rubber in triphasic CO2/toluene/H2O systems with hydrogen peroxide for preparation of biobased polyurethanes
  37. An efficient green synthesis of novel 1H-imidazo[1,2-a]imidazole-3-amine and imidazo[2,1-c][1,2,4]triazole-5-amine derivatives via Strecker reaction under controlled microwave heating
  38. Evaluation of three different green fabrication methods for the synthesis of crystalline ZnO nanoparticles using Pelargonium zonale leaf extract
  39. A highly efficient and multifunctional biomass supporting Ag, Ni, and Cu nanoparticles through wetness impregnation for environmental remediation
  40. Simple one-pot green method for large-scale production of mesalamine, an anti-inflammatory agent
  41. Relationships between step and cumulative PMI and E-factors: implications on estimating material efficiency with respect to charting synthesis optimization strategies
  42. A comparative sorption study of Cr3+ and Cr6+ using mango peels: kinetic, equilibrium and thermodynamic
  43. Effects of acid hydrolysis waste liquid recycle on preparation of microcrystalline cellulose
  44. Use of deep eutectic solvents as catalyst: A mini-review
  45. Microwave-assisted synthesis of pyrrolidinone derivatives using 1,1’-butylenebis(3-sulfo-3H-imidazol-1-ium) chloride in ethylene glycol
  46. Green and eco-friendly synthesis of Co3O4 and Ag-Co3O4: Characterization and photo-catalytic activity
  47. Adsorption optimized of the coal-based material and application for cyanide wastewater treatment
  48. Aloe vera leaf extract mediated green synthesis of selenium nanoparticles and assessment of their In vitro antimicrobial activity against spoilage fungi and pathogenic bacteria strains
  49. Waste phenolic resin derived activated carbon by microwave-assisted KOH activation and application to dye wastewater treatment
  50. Direct ethanol production from cellulose by consortium of Trichoderma reesei and Candida molischiana
  51. Agricultural waste biomass-assisted nanostructures: Synthesis and application
  52. Biodiesel production from rubber seed oil using calcium oxide derived from eggshell as catalyst – optimization and modeling studies
  53. Study of fabrication of fully aqueous solution processed SnS quantum dot-sensitized solar cell
  54. Assessment of aqueous extract of Gypsophila aretioides for inhibitory effects on calcium carbonate formation
  55. An environmentally friendly acylation reaction of 2-methylnaphthalene in solvent-free condition in a micro-channel reactor
  56. Aegle marmelos phytochemical stabilized synthesis and characterization of ZnO nanoparticles and their role against agriculture and food pathogen
  57. A reactive coupling process for co-production of solketal and biodiesel
  58. Optimization of the asymmetric synthesis of (S)-1-phenylethanol using Ispir bean as whole-cell biocatalyst
  59. Synthesis of pyrazolopyridine and pyrazoloquinoline derivatives by one-pot, three-component reactions of arylglyoxals, 3-methyl-1-aryl-1H-pyrazol-5-amines and cyclic 1,3-dicarbonyl compounds in the presence of tetrapropylammonium bromide
  60. Preconcentration of morphine in urine sample using a green and solvent-free microextraction method
  61. Extraction of glycyrrhizic acid by aqueous two-phase system formed by PEG and two environmentally friendly organic acid salts - sodium citrate and sodium tartrate
  62. Green synthesis of copper oxide nanoparticles using Juglans regia leaf extract and assessment of their physico-chemical and biological properties
  63. Deep eutectic solvents (DESs) as powerful and recyclable catalysts and solvents for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones/thiones
  64. Biosynthesis, characterization and anti-microbial activity of silver nanoparticle based gel hand wash
  65. Efficient and selective microwave-assisted O-methylation of phenolic compounds using tetramethylammonium hydroxide (TMAH)
  66. Anticoagulant, thrombolytic and antibacterial activities of Euphorbia acruensis latex-mediated bioengineered silver nanoparticles
  67. Volcanic ash as reusable catalyst in the green synthesis of 3H-1,5-benzodiazepines
  68. Green synthesis, anionic polymerization of 1,4-bis(methacryloyl)piperazine using Algerian clay as catalyst
  69. Selenium supplementation during fermentation with sugar beet molasses and Saccharomyces cerevisiae to increase bioethanol production
  70. Biosynthetic potential assessment of four food pathogenic bacteria in hydrothermally silver nanoparticles fabrication
  71. Investigating the effectiveness of classical and eco-friendly approaches for synthesis of dialdehydes from organic dihalides
  72. Pyrolysis of palm oil using zeolite catalyst and characterization of the boil-oil
  73. Azadirachta indica leaves extract assisted green synthesis of Ag-TiO2 for degradation of Methylene blue and Rhodamine B dyes in aqueous medium
  74. Synthesis of vitamin E succinate catalyzed by nano-SiO2 immobilized DMAP derivative in mixed solvent system
  75. Extraction of phytosterols from melon (Cucumis melo) seeds by supercritical CO2 as a clean technology
  76. Production of uronic acids by hydrothermolysis of pectin as a model substance for plant biomass waste
  77. Biofabrication of highly pure copper oxide nanoparticles using wheat seed extract and their catalytic activity: A mechanistic approach
  78. Intelligent modeling and optimization of emulsion aggregation method for producing green printing ink
  79. Improved removal of methylene blue on modified hierarchical zeolite Y: Achieved by a “destructive-constructive” method
  80. Two different facile and efficient approaches for the synthesis of various N-arylacetamides via N-acetylation of arylamines and straightforward one-pot reductive acetylation of nitroarenes promoted by recyclable CuFe2O4 nanoparticles in water
  81. Optimization of acid catalyzed esterification and mixed metal oxide catalyzed transesterification for biodiesel production from Moringa oleifera oil
  82. Kinetics and the fluidity of the stearic acid esters with different carbon backbones
  83. Aiming for a standardized protocol for preparing a process green synthesis report and for ranking multiple synthesis plans to a common target product
  84. Microstructure and luminescence of VO2 (B) nanoparticle synthesis by hydrothermal method
  85. Optimization of uranium removal from uranium plant wastewater by response surface methodology (RSM)
  86. Microwave drying of nickel-containing residue: dielectric properties, kinetics, and energy aspects
  87. Simple and convenient two step synthesis of 5-bromo-2,3-dimethoxy-6-methyl-1,4-benzoquinone
  88. Biodiesel production from waste cooking oil
  89. The effect of activation temperature on structure and properties of blue coke-based activated carbon by CO2 activation
  90. Optimization of reaction parameters for the green synthesis of zero valent iron nanoparticles using pine tree needles
  91. Microwave-assisted protocol for squalene isolation and conversion from oil-deodoriser distillates
  92. Denitrification performance of rare earth tailings-based catalysts
  93. Facile synthesis of silver nanoparticles using Averrhoa bilimbi L and Plum extracts and investigation on the synergistic bioactivity using in vitro models
  94. Green production of AgNPs and their phytostimulatory impact
  95. Photocatalytic activity of Ag/Ni bi-metallic nanoparticles on textile dye removal
  96. Topical Issue: Green Process Engineering / Guest Editors: Martine Poux, Patrick Cognet
  97. Modelling and optimisation of oxidative desulphurisation of tyre-derived oil via central composite design approach
  98. CO2 sequestration by carbonation of olivine: a new process for optimal separation of the solids produced
  99. Organic carbonates synthesis improved by pervaporation for CO2 utilisation
  100. Production of starch nanoparticles through solvent-antisolvent precipitation in a spinning disc reactor
  101. A kinetic study of Zn halide/TBAB-catalysed fixation of CO2 with styrene oxide in propylene carbonate
  102. Topical on Green Process Engineering
https://doi.org/10.1515/gps-2019-0004
Keywords for this article
microwave-assisted synthesis; pyrrolidinone; sulfonic-functionalized ionic liquid; electronic effect; cation effect
Creative Commons
BY 4.0

Articles in the same Issue

  1. Regular Articles
  2. Studies on the preparation and properties of biodegradable polyester from soybean oil
  3. Flow-mode biodiesel production from palm oil using a pressurized microwave reactor
  4. Reduction of free fatty acids in waste oil for biodiesel production by glycerolysis: investigation and optimization of process parameters
  5. Saccharin: a cheap and mild acidic agent for the synthesis of azo dyes via telescoped dediazotization
  6. Optimization of lipase-catalyzed synthesis of polyethylene glycol stearate in a solvent-free system
  7. Green synthesis of iron oxide nanoparticles using Platanus orientalis leaf extract for antifungal activity
  8. Ultrasound assisted chemical activation of peanut husk for copper removal
  9. Room temperature silanization of Fe3O4 for the preparation of phenyl functionalized magnetic adsorbent for dispersive solid phase extraction for the extraction of phthalates in water
  10. Evaluation of the saponin green extraction from Ziziphus spina-christi leaves using hydrothermal, microwave and Bain-Marie water bath heating methods
  11. Oxidation of dibenzothiophene using the heterogeneous catalyst of tungsten-based carbon nanotubes
  12. Calcined sodium silicate as an efficient and benign heterogeneous catalyst for the transesterification of natural lecithin to L-α-glycerophosphocholine
  13. Synergistic effect between CO2 and H2O2 on ethylbenzene oxidation catalyzed by carbon supported heteropolyanion catalysts
  14. Hydrocyanation of 2-arylmethyleneindan-1,3-diones using potassium hexacyanoferrate(II) as a nontoxic cyanating agent
  15. Green synthesis of hydratropic aldehyde from α-methylstyrene catalyzed by Al2O3-supported metal phthalocyanines
  16. Environmentally benign chemical recycling of polycarbonate wastes: comparison of micro- and nano-TiO2 solid support efficiencies
  17. Medicago polymorpha-mediated antibacterial silver nanoparticles in the reduction of methyl orange
  18. Production of value-added chemicals from esterification of waste glycerol over MCM-41 supported catalysts
  19. Green synthesis of zerovalent copper nanoparticles for efficient reduction of toxic azo dyes congo red and methyl orange
  20. Optimization of the biological synthesis of silver nanoparticles using Penicillium oxalicum GRS-1 and their antimicrobial effects against common food-borne pathogens
  21. Optimization of submerged fermentation conditions to overproduce bioethanol using two industrial and traditional Saccharomyces cerevisiae strains
  22. Extraction of In3+ and Fe3+ from sulfate solutions by using a 3D-printed “Y”-shaped microreactor
  23. Foliar-mediated Ag:ZnO nanophotocatalysts: green synthesis, characterization, pollutants degradation, and in vitro biocidal activity
  24. Green cyclic acetals production by glycerol etherification reaction with benzaldehyde using cationic acidic resin
  25. Biosynthesis, characterization and antimicrobial activities assessment of fabricated selenium nanoparticles using Pelargonium zonale leaf extract
  26. Synthesis of high surface area magnesia by using walnut shell as a template
  27. Controllable biosynthesis of silver nanoparticles using actinobacterial strains
  28. Green vegetation: a promising source of color dyes
  29. Mechano-chemical synthesis of ammonia and acetic acid from inorganic materials in water
  30. Green synthesis and structural characterization of novel N1-substituted 3,4-dihydropyrimidin-2(1H)-ones
  31. Biodiesel production from cotton oil using heterogeneous CaO catalysts from eggshells prepared at different calcination temperatures
  32. Regeneration of spent mercury catalyst for the treatment of dye wastewater by the microwave and ultrasonic spray-assisted method
  33. Green synthesis of the innovative super paramagnetic nanoparticles from the leaves extract of Fraxinus chinensis Roxb and their application for the decolourisation of toxic dyes
  34. Biogenic ZnO nanoparticles: a study of blueshift of optical band gap and photocatalytic degradation of reactive yellow 186 dye under direct sunlight
  35. Leached compounds from the extracts of pomegranate peel, green coconut shell, and karuvelam wood for the removal of hexavalent chromium
  36. Enhancement of molecular weight reduction of natural rubber in triphasic CO2/toluene/H2O systems with hydrogen peroxide for preparation of biobased polyurethanes
  37. An efficient green synthesis of novel 1H-imidazo[1,2-a]imidazole-3-amine and imidazo[2,1-c][1,2,4]triazole-5-amine derivatives via Strecker reaction under controlled microwave heating
  38. Evaluation of three different green fabrication methods for the synthesis of crystalline ZnO nanoparticles using Pelargonium zonale leaf extract
  39. A highly efficient and multifunctional biomass supporting Ag, Ni, and Cu nanoparticles through wetness impregnation for environmental remediation
  40. Simple one-pot green method for large-scale production of mesalamine, an anti-inflammatory agent
  41. Relationships between step and cumulative PMI and E-factors: implications on estimating material efficiency with respect to charting synthesis optimization strategies
  42. A comparative sorption study of Cr3+ and Cr6+ using mango peels: kinetic, equilibrium and thermodynamic
  43. Effects of acid hydrolysis waste liquid recycle on preparation of microcrystalline cellulose
  44. Use of deep eutectic solvents as catalyst: A mini-review
  45. Microwave-assisted synthesis of pyrrolidinone derivatives using 1,1’-butylenebis(3-sulfo-3H-imidazol-1-ium) chloride in ethylene glycol
  46. Green and eco-friendly synthesis of Co3O4 and Ag-Co3O4: Characterization and photo-catalytic activity
  47. Adsorption optimized of the coal-based material and application for cyanide wastewater treatment
  48. Aloe vera leaf extract mediated green synthesis of selenium nanoparticles and assessment of their In vitro antimicrobial activity against spoilage fungi and pathogenic bacteria strains
  49. Waste phenolic resin derived activated carbon by microwave-assisted KOH activation and application to dye wastewater treatment
  50. Direct ethanol production from cellulose by consortium of Trichoderma reesei and Candida molischiana
  51. Agricultural waste biomass-assisted nanostructures: Synthesis and application
  52. Biodiesel production from rubber seed oil using calcium oxide derived from eggshell as catalyst – optimization and modeling studies
  53. Study of fabrication of fully aqueous solution processed SnS quantum dot-sensitized solar cell
  54. Assessment of aqueous extract of Gypsophila aretioides for inhibitory effects on calcium carbonate formation
  55. An environmentally friendly acylation reaction of 2-methylnaphthalene in solvent-free condition in a micro-channel reactor
  56. Aegle marmelos phytochemical stabilized synthesis and characterization of ZnO nanoparticles and their role against agriculture and food pathogen
  57. A reactive coupling process for co-production of solketal and biodiesel
  58. Optimization of the asymmetric synthesis of (S)-1-phenylethanol using Ispir bean as whole-cell biocatalyst
  59. Synthesis of pyrazolopyridine and pyrazoloquinoline derivatives by one-pot, three-component reactions of arylglyoxals, 3-methyl-1-aryl-1H-pyrazol-5-amines and cyclic 1,3-dicarbonyl compounds in the presence of tetrapropylammonium bromide
  60. Preconcentration of morphine in urine sample using a green and solvent-free microextraction method
  61. Extraction of glycyrrhizic acid by aqueous two-phase system formed by PEG and two environmentally friendly organic acid salts - sodium citrate and sodium tartrate
  62. Green synthesis of copper oxide nanoparticles using Juglans regia leaf extract and assessment of their physico-chemical and biological properties
  63. Deep eutectic solvents (DESs) as powerful and recyclable catalysts and solvents for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones/thiones
  64. Biosynthesis, characterization and anti-microbial activity of silver nanoparticle based gel hand wash
  65. Efficient and selective microwave-assisted O-methylation of phenolic compounds using tetramethylammonium hydroxide (TMAH)
  66. Anticoagulant, thrombolytic and antibacterial activities of Euphorbia acruensis latex-mediated bioengineered silver nanoparticles
  67. Volcanic ash as reusable catalyst in the green synthesis of 3H-1,5-benzodiazepines
  68. Green synthesis, anionic polymerization of 1,4-bis(methacryloyl)piperazine using Algerian clay as catalyst
  69. Selenium supplementation during fermentation with sugar beet molasses and Saccharomyces cerevisiae to increase bioethanol production
  70. Biosynthetic potential assessment of four food pathogenic bacteria in hydrothermally silver nanoparticles fabrication
  71. Investigating the effectiveness of classical and eco-friendly approaches for synthesis of dialdehydes from organic dihalides
  72. Pyrolysis of palm oil using zeolite catalyst and characterization of the boil-oil
  73. Azadirachta indica leaves extract assisted green synthesis of Ag-TiO2 for degradation of Methylene blue and Rhodamine B dyes in aqueous medium
  74. Synthesis of vitamin E succinate catalyzed by nano-SiO2 immobilized DMAP derivative in mixed solvent system
  75. Extraction of phytosterols from melon (Cucumis melo) seeds by supercritical CO2 as a clean technology
  76. Production of uronic acids by hydrothermolysis of pectin as a model substance for plant biomass waste
  77. Biofabrication of highly pure copper oxide nanoparticles using wheat seed extract and their catalytic activity: A mechanistic approach
  78. Intelligent modeling and optimization of emulsion aggregation method for producing green printing ink
  79. Improved removal of methylene blue on modified hierarchical zeolite Y: Achieved by a “destructive-constructive” method
  80. Two different facile and efficient approaches for the synthesis of various N-arylacetamides via N-acetylation of arylamines and straightforward one-pot reductive acetylation of nitroarenes promoted by recyclable CuFe2O4 nanoparticles in water
  81. Optimization of acid catalyzed esterification and mixed metal oxide catalyzed transesterification for biodiesel production from Moringa oleifera oil
  82. Kinetics and the fluidity of the stearic acid esters with different carbon backbones
  83. Aiming for a standardized protocol for preparing a process green synthesis report and for ranking multiple synthesis plans to a common target product
  84. Microstructure and luminescence of VO2 (B) nanoparticle synthesis by hydrothermal method
  85. Optimization of uranium removal from uranium plant wastewater by response surface methodology (RSM)
  86. Microwave drying of nickel-containing residue: dielectric properties, kinetics, and energy aspects
  87. Simple and convenient two step synthesis of 5-bromo-2,3-dimethoxy-6-methyl-1,4-benzoquinone
  88. Biodiesel production from waste cooking oil
  89. The effect of activation temperature on structure and properties of blue coke-based activated carbon by CO2 activation
  90. Optimization of reaction parameters for the green synthesis of zero valent iron nanoparticles using pine tree needles
  91. Microwave-assisted protocol for squalene isolation and conversion from oil-deodoriser distillates
  92. Denitrification performance of rare earth tailings-based catalysts
  93. Facile synthesis of silver nanoparticles using Averrhoa bilimbi L and Plum extracts and investigation on the synergistic bioactivity using in vitro models
  94. Green production of AgNPs and their phytostimulatory impact
  95. Photocatalytic activity of Ag/Ni bi-metallic nanoparticles on textile dye removal
  96. Topical Issue: Green Process Engineering / Guest Editors: Martine Poux, Patrick Cognet
  97. Modelling and optimisation of oxidative desulphurisation of tyre-derived oil via central composite design approach
  98. CO2 sequestration by carbonation of olivine: a new process for optimal separation of the solids produced
  99. Organic carbonates synthesis improved by pervaporation for CO2 utilisation
  100. Production of starch nanoparticles through solvent-antisolvent precipitation in a spinning disc reactor
  101. A kinetic study of Zn halide/TBAB-catalysed fixation of CO2 with styrene oxide in propylene carbonate
  102. Topical on Green Process Engineering
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 27.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/gps-2019-0004/html
Scroll to top button