Gold-Decorated 3D 2,6-Diaminopyridine Network: A Robust Catalyst

Jul 12, 2018 - Subsequently, TCT (1.0 g) and DAP (1.63 g) were added to the flask, and the mixture was stirred at 0 °C. Afterward, K2CO3 (1.0 g) was ...
0 downloads 0 Views 3MB Size
Download PDF
Article Cite This: Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

pubs.acs.org/IECR

Gold-Decorated 3D 2,6-Diaminopyridine Network: A Robust Catalyst for the Bromination of Aromatic Compounds Ali Pourjavadi,*,† Nahid Keshavarzi,† Seyed Hassan Hosseini,‡ and Firouz Matloubi Moghaddam§ †

Polymer Research Laboratory, Department of Chemistry, Sharif University of Technology, Tehran, Iran Department of Chemical Engineering, University of Science and Technology of Mazandaran, Behshahr, Iran § Laboratory of Organic Synthesis and Natural Products, Department of Chemistry, Sharif University of Technology, Tehran, Iran ‡

Ind. Eng. Chem. Res. Downloaded from pubs.acs.org by UNIV OF NEW ENGLAND on 07/13/18. For personal use only.

S Supporting Information *

ABSTRACT: This article reports the synthesis of a magnetic heterogeneous catalyst through the decoration of gold ions onto the cross-linked polymeric nanocomposite from 2,6-diaminopyridine. The activity of the resulting catalyst was then evaluated in the bromination of aromatic compounds. The nitrogen rich support showed a high affinity to gold ions, and the measured content of Au was 0.76 mmol g−1. The structure of the catalyst was fully characterized by using Fourier-transform infrared spectroscopy, thermogravimetric analysis, atomic absorption spectroscopy, transmission electron microscopy, scanning electron microscope, energy-dispersive X-ray spectroscopy, Brunauer− Emmett−Teller surface area analysis, a vibrating sample magnetometer, and X-ray diffraction techniques. Various substituted arenes were converted to the corresponding Br-containing aromatic compounds in a good to excellent yield using 300 mg of catalyst. It is worth mentioning, that the catalyst was simply collected from the solution and reused in eight cycles without significant loss of its activity.

■

INTRODUCTION Haloarenes have been used as intermediates in biologically active compounds. These compounds are specifically useful for the synthesis of drugs, pharmaceuticals, agrochemicals, pigments, and photographic materials.1 Aryl bromides are starting materials in several important organic reactions, including Heck, Suzuki, and Sonogashira reactions.2 The direct method for the bromination of aromatic systems uses Br2 as a reagent. However, the main problem of this reaction is that the generation of highly corrosive and toxic HBr as a byproduct, which causes serious environmental issues.3 Different types of protocols have been developed for the bromination of aromatic substrates, but the most commonly used reagent, N-bromosuccinic imide (NBS), possesses easy handling and low toxicity.4 However, when NBS is used for the bromination of aromatic compounds, a large amount of a strong Lewis or Bronsted acid is usually required as the catalyst in harsh reaction conditions.5 Wang and co-workers have reported a mild protocol for efficient bromination of various types of arenes by using AuCl3 as the catalyst.6 They reported that only a tiny amount of AuCl3 catalyst enhanced the bromination reaction, and the reaction can be performed at lower temperatures.7 The mechanism of the reaction showed that a gold atom could create a complex with an aromatic compound and NBS, which enhanced the reactivity of both substrates.7a In the past several decades, numerous papers have reported the application of Au as catalyst in various organic transformations.8 Major problems © XXXX American Chemical Society

in the Au-catalyzed reactions are the high cost of gold and the difficult recycling of the catalyst, which have limited the widespread industrial application of Au-catalysts. To solve these drawbacks, a versatile approach is the heterogneization of Au.9 Various types of solid beds have been introduced for immobilization of gold ions, such as magnetic nanoparticles,10 silica,11 cross-linked polymers,12 and alumina.9f,13 Magnetic nanoparticles have advantages, such as easy separation, high surface area, good dispersibility, and excellent stability in various conditions, compared to those of mesoporous silica compounds for the immobilization of gold.15 In spite of the several advantages of heterogeneous catalytic systems, the remaining problem is the low loading amount of the active spices (gold). In the recent decade, use of threedimensional (3D) polymeric networks for the immobilization of active catalysts has been developed as an ideal way to increase the loading amount of metal ions.14 The main reasons for choosing the 3D polymeric networks as metal supports are the porosity and the presence of numerous chelating sites.14g Since each polymeric chain is composed of several coordinating monomers, the final 3D polymeric network can carry a large number of metal ions. The decoration of magnetic nanoparticles into the 3D polymeric network resulted in the Received: March 16, 2018 Revised: June 22, 2018 Accepted: June 26, 2018

A

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research

Figure 1. Preparation of the MNP@DAPN/Au catalyst.

production of a magnetic polymeric support which has the benefits of both a magnetic collection and high loading capacity. Moreover, by the incorporation of magnetic nanoparticles into the polymeric network, the thermal, mechanical, and chemical stability of the resulted nanocomposite could be improved in comparison with the cross-linked networks without any nanoparticle fillers.16 Herein, we prepare a heterogeneous magnetic catalyst based on 3D cross-linked 2,6-diaminopyridine (DAP) for the immobilization of Au. The applicability of the catalyst was probed through aromatic bromination.

confirmed by a nuclear magnetic resonance (NMR) (Bruker, Avance DRX-500) spectrometer using CDCl3 as the solvent. Synthesis of Modified Magnetic Nanoparticles (MNP@APTS). A chemical co-precipitation method was used to produce Fe3O4 according to a previous report.17 At first, a solution of 13.6 g of Fe(III) and 5.0 g of Fe(II) in 500 mL of deionized (DI) water under an N2 atmosphere was vigorously stirred. Then, the pH of the solution was adjusted to 12 by the addition of the NH3 solution. The black precipitate of Fe3O4 was immediately formed. In a silica coating procedure, the resulting Fe3O4 nanoparticles (3.0 g) and a mixture of ethanol/ water (4:1, 400 mL) were added to a 500 mL round-bottom flask. The nanoparticles were ultrasonically dispersed, and then NH3 was added to the flask until the solution reached a pH of 10. Afterward, 15 mL of TEOS was added dropwise to the solution, and the flask was heated at 50 °C under a nitrogen atmosphere. The solution was vigorously stirred for 6 h to allow the complete coating of the magnetic particles with silica shells. Finally, black nanoparticles were magnetically separated and washed three times with ethanol (30 mL for each time). To prepare amine-coated MNPs (MNP@APTS), Fe3O4@ SiO2 (2.0 g), APTS (4.0 mL), and toluene (60 mL) were poured into a 100 mL round-bottom flask equipped with a condenser. Then the flask was placed in an oil bath and heated to 110 °C while the solution was stirred using a magnetic stirrer for 2 h. The final products were separated by using an external magnet and washed with water and ethanol; then, they were dried in an oven at 60 °C. Synthesis of the Catalyst (MNP@DAPN/Au). For the synthesis of the catalyst, MNP@APTS (0.50 g) was ultrasonically dispersed for 20 min in dry toluene (20 mL) in a roundbottom flask. Subsequently, TCT (1.0 g) and DAP (1.63 g) were added to the flask, and the mixture was stirred at 0 °C. Afterward, K2CO3 (1.0 g) was added to the flask, and stirring was continued for 4 h at room temperature. Then the flask was heated to 90 °C, and stirring was continued for another 24 h. The resulting MNP@DAPN were magnetically collected from the solution washed with methanol (3 × 20 mL) to remove

■

EXPERIMENTAL SECTION Reagents and Analyses. Iron(III) chloride (FeCl3· 6H2O), iron(II) chloride (FeCl2·4H2O), tetraethylorthosilicate (TEOS), NH3 (25%), 2,4,6-trichloro-1,3,5-triazine (TCT), DAP, (3-amino propyl)triethoxysilane (APTS), and tetrachloroauric(III) acid trihydrate (AuHCl4·3H2O) were purchased from Merck. Toluene (Merck) was super dried over sodium before use. Samples were mixed with KBr to produce a tablet to record their Fourier-transform infrared (FT-IR) spectra (ABB Bomem MB 100 spectrophotometer). Thermogravimetric analysis (TGA) (Netzsch-TGA 209 F1 instrument) was performed at a heating rate of 10 °C under a nitrogen atmosphere. The crystalline structure of the sample was investigated using X-ray diffraction (XRD) (STOE-IPDS 2T diffractometer, using Cu Kα radiation). The surface morphology of the sample was observed by a scanning electron microscope (SEM) (Mira3 Tescan microscope). A transmission electron microscope (TEM) (Philips CM30 electron microscope) was used to identify the nanoparticles in the sample. A vibrating sample magnetometer (VSM) instrument (Meghnatis Daghigh Kavir Co., Kashan, Iran) was applied to measure the magnetic properties of the samples. The surface area was measured using a Brunauer−Emmett−Teller (BET) surface analysis instrument (Belsorp mini II). The structures of the products were B

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research unreacted materials. The solid brown products were dried at 60 °C for 12 h. For the loading of gold ions onto the support (MNP@DAPN), a solution of HAuCl4 (1.0 mL, 0.2 M) and MNP@ DAPN (0.30 g) was added to 20 mL of DI water, and the solution was stirred for 24 h. Then, the final catalyst (MNP@ DAPN/Au) was magnetically separated, washed with water and ethanol, and then dried at 60 °C for 10 h. In order to measure gold content in the catalyst, 0.05 g of catalyst (MNP@ DAPN/Au) was dissolved in 3 mL of a mixture of HCl/HNO3 (2:1). Then, the mixture was heated to destroy the polymeric network. The solution was diluted to 50 mL with distilled water. The amount of gold in the solution was determined by atomic absorption spectroscopy. General Procedure for the Bromination Reaction. In a 10 mL round-bottom flask, NBS (1.2 mmol), substrate (1.0 mmol), DCE (2 mL), and MNP@DAPN/Au (0.30 g) were added, and then the reaction mixture was stirred under a reflux condition at 80 °C for an appropriate time. After completion of the reaction (monitored by TLC), the catalyst was magnetically separated, washed three times with methanol, and dried. The reaction mixture was concentrated under reduced pressure, and the product was purified by column chromatography.

Figure 3. TGA analysis of MNP@APTS (a) and MNP@DAPN (b).

■

RESULTS AND DISCUSSION Preparation of the Catalyst. The MNP@DAPN/Au catalyst was prepared in a few steps through Au immobilization

Figure 4. TEM (a) SEM (b) image of MNP@DAPN/Au.

through the reaction between TCT and DAP in the presence of MNP@APTS. The cross-linking occurs by the substitution of each of three chlorides of TCT by two amine groups of DAP. The 3D structure of the polymeric network was completely formed when the reaction mixture was heated, which led to the complete substitution of all three chlorides in TCT. The immobilization of Au on the surface of the magnetic nanocomposite was carried out by dispersion of the MNP@ DAPN in a solution of Au ions. The Au ions were effectively adsorbed onto the resulting support by coordination with NNN pincer-like groups. This high nitrogen-rich support, which bears the NNN pincer ligand, can strongly hold a large amount of Au on it while no leaching can occur (Figure. 1). Characterization of the Catalyst. Figure 2a−d shows the FT-IR spectra of the magnetic nanoparticles Fe3O4, MNPs, MNP@APTS, and MNP@DAPN. The absorption peak at 621 cm −1 corresponded to the stretching vibration of the Fe−O bond (Figure 2a). A strong absorption band at 1100 cm −1 is related to the stretching vibration of Si−O coated onto the surface of Fe3O4 (Figure 2b).18 The IR spectrum of MNP@ APTS clearly shows the bending and stretching vibration of the N−H bond at 1517 and 3414 cm −1, respectively, confirming the successful amine coating of MNPs (Figure 2c).19 The formation of the final catalyst is confirmed by the appearance of peaks at 1400 and 1600 cm −1, which are attributed to the stretching vibration of N−H and CN in DAP rings. The IR spectrum of MNP@DAPN has an absorption band at 1517 cm −1 , which is assigned to the CN stretching vibration of triazine rings (Figure 2d).20 In addition, the peaks at 2919 and 3386 cm −1 are assigned to the C−H and NH2 stretching, which confirms the proposed structure of the prepared support. The thermal stabilities of MNP@APTS and MNP@DAPN were investigated by TGA in the temperature range of 25−900 °C, as presented in Figure 3. The weight loss below 300 °C is

Figure 2. FT-IR spectra of Fe3O4 (a), MNPs (b), MNP@APTS (c), and MNP@DAPN (d).

into the cross-linked polymeric network which contains DAP groups, as shown in Figure 1. The first step involves the synthesis of magnetic nanoparticles (Fe3O4) through the coprecipitation technique based on a reported method.13a The surface of Fe3O4 was functionalized by TEOS to improve its chemical and thermal stabilities and to make the functionalization easier. Afterward, the surfaces of the magnetic particles were modified by amine groups to ensure that the particles were covalently attached to the polymeric network in the next steps. The final magnetic bed (MNP@DAPN) was prepared C

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research

Figure 5. EDS analysis of MNP@DAPN/Au (a). XRD pattern of MNP@ DAPN/Au (b).

Figure 6. The N2 adsorption−desorption isotherm (a) and the BJH pore size distribution plot of MNP@DAPN/Au (b).

catalyst has an excellent stability, which is crucial for the catalyst applicability under harsh reaction conditions. The loading amount of Au in MNP@DAPN was calculated to be 0.76 mmol g−1, according to the results of atomic absorption spectroscopy. The morphology of the synthesized catalyst was confirmed using TEM and SEM (Figure. 4a,b, respectively). TEM images of the catalyst showed that the Au was dispersed well in the polymeric network. Also, the dark MNPs with 12 nm diameters can be clearly seen in the polymeric network. The SEM image shows that the surface of the catalyst is porous, which improved the substrate adsorption in the catalytic reactions. Energy-dispersive X-ray spectroscopy (EDS) analysis of MNP@DAPN/Au is depicted in Figure. 5a, which clearly establishes the presence of Au in the catalyst structure. The XRD patterns of MNP@DAPN/Au (Figure. 5b) show peaks at 2θ values of 35, 38, 43, 53, 57, 62, and 64°, which are characteristic peaks of Fe3O4. This XRD pattern confirms that the modification did not affect the crystalline structure of Fe3O4 nanoparticles. The observed peak at 38° is matched for Au in the structure of the catalyst.24 The surface area and pore size distribution of the composite can be obtained by the N2 adsorption−desorption isotherm, as shown in Figure 6a,b. The porous structure of MNP@DAPN was confirmed by BET gas adsorption studies. The average pore diameter of 5 nm is calculated by the Barrett−Joyner− Halenda (BJH) analysis, which also suggests the porous structure. The prepared magnetic nanocomposite in this work has a specific surface area of 16.59 m2g−1. Catalytic Performance of MNP@DAPN/Au. In order to investigate the catalytic activity of MNP@DAPN/Au, the

Table 1. Optimization of the Reaction Conditions for Aromatic Brominationa

entry

catalyst

cat amount (mg)

1 2 3 4 5 6 7 8 9 10 11 12 13

TCT@DAPN/Au MNP@DAPN MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au MNP@DAPN/Au

100 100 100 100 100 200 200 50 100 200 300 100 50

solvent

T (°C)

time (h)

yield (%)b

DCE DCE CHCl3 CH2Cl2 CH2Cl2 CH2Cl2 DCE DCE DCE DCE DCE DCE DCE

80 80 RT RT 60 60 60 80 80 80 80 80 80

24 48 48 48 36 24 24 12 12 12 8 48 72

73 nr nr trace 25 32 56 30 78 87 97 93 69

a

Reaction condition: Anisole (1 mmol), NBS (1.2 mmol), solvent (2 mL), and reflux. bIsolated yield.

due to the evaporation of water, solvent, and volatile materials.21 The weight loss at around 250 °C is attributed to the decomposition of aminopropyl groups in the TGA curve of MNP@APTS (Figure 3a).22 The polymeric network was decomposed completely at 500−600 °C.23 According to the TGA results, the content of MNPs was evaluated acutely at 43.91 wt % of the support. The TGA results confirm that the D

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research Table 2. Bromination of Aromatics with the MNP@DAPN/Au Catalysta

E

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research Table 2. continued

a e

DCE (2 mL), substrate (1.0 mmol), NBS (1.2 mmol), catalyst (300 mg), and reflux. bIsolated yields. cSelectfluor: 1.2 mmol. dNCS: 1.2 mmol. NIS: 1.2 mmol.

yield was obtained when the TCT@DAP/Au (2,4,6-trichloro1,3,5-triazine@2,6-diaminopyridine) catalyst (100 mg) was used at 80 °C after 24 h (entries 1, Table 1). When MNP@ DAPN (100 mg) was used as the catalyst, no product was formed even after 48 h (entries 2, Table 1), indicating the catalytic role of Au. Using MNP@DAPN/Au (100 mg) as the catalyst in CH3Cl at room temperature after 48 h gave no product. The reaction gave a trace amount of product in CH2Cl2 solvent at room temperature after 48 h. When the temperature was increased to 60 °C, a small amount of aromatic bromination product was obtained (entries 5, Table 1). However, increasing the amount of catalyst (200 mg) in CH2Cl2 did not show any significant change in the product yield at 60 °C after 24 h (entries 7, Table 1). The results showed that the best condition for the aromatic bromination by MNP@DAPN/Au is using 300 mg of the catalyst in DCE (1, 2-dichloroethane) under a reflux condition in an oil at 80 °C. Using 50 mg of catalyst in DEC after 72 h gave 69% of the products. In addition, the results showed that 93% yield was obtained when using 100 mg of catalyst after 48 h. At the optimized reaction condition, the scope of the protocol was explored with various substituted arenes, and the results are shown in Table 2. The bromination reaction efficiently performed, giving the corresponding aryl bromides in good to excellent yields. The products of the bromination of electron-rich aromatic compounds (entries 3, 4, 5, and 9) were obtained in excellent yields (92−97%). The aromatic compounds containing halogen groups (I, Cl, and F) also gave the products in good yields (72−86%). The aromatic compounds with electron-withdrawing groups, such as NO2 and CO2H, gave lower yields, even in longer reaction times. In addition, we examined the fluorination, chlorination, and iodination of 1,3-dinitrobenzene using selectfluor, NCS, and NIS respectively. 1HNMR and 13CNMR data of all of the products are provided in the Supporting Information. Reusability of the Catalyst. The reusability of the catalysts is an important advantage which should be examined in the catalytic reactions. In this work, the activity of MNP@DAPN/ Au was investigated in the bromination of anisole, and the

Figure 7. Recycling capability of MNPs@DAPN/Au.

Table 3. Comparison of MNP@DAPN/Au with Other Catalysts Reported for Aromatic Bromination

catalyst (mol %) HCl (20) HZSM-5 (100 mg) Fe(NO3)3·1.5N2O4(10) [bmim]PF6 (20) ZrCl4 (20) AuCl3 (1) MNP@DAPN/Au (300 mg)

solvent acetone CCl4 CH2Cl2 CH2Cl2 DCE DCE

T (°C)

time (min)

yield (%)

ref

RT RT RT RT RT 80 80

15 100 20 25 300 1200 240

98 70 98 92 98 96 97

5a 1 5e 4g 3 23 this work

aromatic bromination reaction of anisole in the presence of NBS was chosen as a model reaction. In order to obtain the best reaction conditions for aromatic bromination, several factors, such as the amount of catalyst, solvent, and temperature, were optimized. The results showed that 73% F

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research

catalyzed cross-coupling reactions of organoboron compounds. Chem. Rev. 1995, 95 (7), 2457−2483. (c) Cabri, W.; Candiani, I. Recent developments and new perspectives in the Heck reaction. Acc. Chem. Res. 1995, 28 (1), 2−7. (d) Chinchilla, R.; Nájera, C. Recent advances in Sonogashira reactions. Chem. Soc. Rev. 2011, 40 (10), 5084−5121. (e) Krause, S. B.; McAtee, J. R.; Yap, G. P.; Watson, D. A. A BenchStable, Single-Component Precatalyst for Silyl−Heck Reactions. Org. Lett. 2017, 19 (20), 5641−5644. (f) Gallop, C. W.; Chen, M.-T.; Navarro, O. Sonogashira couplings catalyzed by collaborative (Nheterocyclic carbene)-copper and-palladium complexes. Org. Lett. 2014, 16 (14), 3724−3727. (g) Chen, F.; Huang, M.; Li, Y. Synthesis of a novel cellulose microencapsulated palladium nanoparticle and its catalytic activities in Suzuki−Miyaura and Mizoroki−Heck reactions. Ind. Eng. Chem. Res. 2014, 53 (20), 8339−8345. (3) (a) Vyas, P. V.; Bhatt, A. K.; Ramachandraiah, G.; Bedekar, A. V. Environmentally benign chlorination and bromination of aromatic amines, hydrocarbons and naphthols. Tetrahedron Lett. 2003, 44 (21), 4085−4088. (b) Torii, S.; Tanaka, H.; Siroi, T.; Akada, M. Regiospecific electroacetoxylation of 4-methylphenyl acetate to form 4-acetoxybenzyl acetate. A significant procedure for vanillin synthesis involving novel etherification methods of aryl bromides. J. Org. Chem. 1979, 44 (19), 3305−3310. (c) Coburn, C. E.; Anderson, D. K.; Swenton, J. S. Convenient AB-ring segments for anthracyclinone synthesis via bishydroxylation of 2-ethyl-5, 8-dimethoxy-7-bromo-1tetralone. J. Org. Chem. 1983, 48 (9), 1455−1461. (d) Kumar, L.; Mahajan, T.; Agarwal, D. Bromination of deactivated aromatic compounds with sodium bromide/sodium periodate under mild acidic conditions. Ind. Eng. Chem. Res. 2012, 51 (36), 11593−11597. (4) (a) Joshi, G.; Adimurthy, S. Environment-Friendly Bromination of Aromatic Heterocycles Using a Bromide−Bromate Couple in an Aqueous Medium. Ind. Eng. Chem. Res. 2011, 50 (21), 12271−12275. (b) Majetich, G.; Hicks, R.; Reister, S. Electrophilic aromatic bromination using bromodimethylsulfonium bromide generated in situ. J. Org. Chem. 1997, 62 (13), 4321−4326. (c) Roy, S. C.; Guin, C.; Rana, K. K.; Maiti, G. An efficient chemo and regioselective oxidative nuclear bromination of activated aromatic compounds using lithium bromide and ceric ammonium nitrate. Tetrahedron Lett. 2001, 42 (39), 6941−6942. (d) Yanovskaya, L.; Terentyev, A.; Belenky, L. Bromination with Dioxane Dibromide. I. Bromination of Phenols. J. Gen. Chem. USSR (Engl. Transl.) 1952, 22, 1594−1598. (e) Rosenmund, K.; Kuhnhenn, W. A method for the bromination of organic compounds. Ber. Dtsch. Chem. Ges. B 1923, 56, 1262−1269. (f) Muathen, H. A. 1, 8-Diazabicyclo [5.4. 0] undec-7-ene hydrobromide perbromide: A new mild stable brominating agent for aromatic compounds. J. Org. Chem. 1992, 57 (9), 2740−2741. (g) Kajigaeshi, S.; Kakinami, T.; Okamoto, T.; Nakamura, H.; Fujikawa, M. Halogenation using quaternary ammonium polyhalides. IV. Selective bromination of phenols by use of tetraalkylammonium tribromides. Bull. Chem. Soc. Jpn. 1987, 60 (11), 4187−4189. (5) (a) Schmid, H. Bromierungen mit Brom-succinimid bei Gegenwart von Katalysatoren, II. Helv. Chim. Acta 1946, 29 (5), 1144−1151. (b) Lambert, F. L.; Ellis, W. D.; Parry, R. J. Halogenation of aromatic compounds by N-bromo-and N-chlorosuccinimide under ionic conditions. J. Org. Chem. 1965, 30 (1), 304−306. (c) Yadav, J.; Reddy, B.; Baishya, G.; Harshavardhan, S.; Chary, C. J.; Gupta, M. K. Green approach for the conversion of olefins into vic-halohydrins using N-halosuccinimides in ionic liquids. Tetrahedron Lett. 2005, 46 (20), 3569−3572. (d) Zanka, A.; Kubota, A. Practical and efficient chlorination of deactivated anilines and anilides with NCS in 2propanol. Synlett 1999, 1999 (12), 1984−1986. (e) Tanemura, K.; Suzuki, T.; Nishida, Y.; Satsumabayashi, K.; Horaguchi, T. Halogenation of Aromatic Compounds by N-chloro-, N-bromo-, and N-iodosuccinimide. Chem. Lett. 2003, 32 (10), 932−933. (f) Olah, G. A.; Wang, Q.; Sandford, G.; Surya Prakash, G. Synthetic methods and reactions. 181. Iodination of deactivated aromatics with N-iodosuccinimide in trifluoromethanesulfonic acid (NIS-CF3SO3H) via in situ generated superelectrophilic iodine (I) trifluoromethanesulfonate. J. Org. Chem. 1993, 58 (11), 3194−3195. (g) Olah, G.; Wang, Q.; Sandford, G.; Surya Prakash, G. Iodination of deactivated

result is depicted in Figure 7. After completion of the reaction, which was monitored by TLC, the catalyst was magnetically separated and washed with ethanol, and the residue was used for the next run. The recovered catalyst was reused 8 times without any significant decrease in the yield of the product. The results showed that the catalyst is stable under reaction conditions, and no significant leaching occurs. A comparison between the present catalyst and protocols and other reported catalysts is summarized in Table 3. The reaction of anisole with NBS was chosen as the model reaction. It was obvious that, in comparison with the homogeneous catalysts, the heterogeneous catalyst needs to be used at a higher weight percent because the lower activity of the supported catalysts resulted from the lower interaction with substrates. As it can be seen, the present catalysts have the advantage of heterogeneity, magnetic separation, and lower reaction time.

■

CONCLUSION In conclusion, the synthesis of a heterogeneous catalyst for an aromatic bromination reaction by anchoring Au onto a crosslinked polymeric nanocomposite was accomplished. The solid support was prepared by multiple cross-linkings of TCT and DAP in the presence of MNP@APTS. The results demonstrated that the nitrogen-rich support played a key role in adsorbing large amounts of gold ions, and it improved the gold catalyst activity in the aromatic bromination. The prepared heterogeneous catalyst was used as an efficient catalyst in the aromatic bromination with NBS. This catalyst has advantages, including high yield, high loading of Au, high stability, and easy recyclability.

■

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.iecr.8b01179. XRD pattern of MNP@DAPN and 1H and 13C NMR spectral data of compounds (PDF)

■

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]; Phone/Fax: (982)166165311. ORCID

Ali Pourjavadi: 0000-0003-4180-4358 Firouz Matloubi Moghaddam: 0000-0002-8418-9888 Notes

The authors declare no competing financial interest.

■

REFERENCES

(1) (a) Paul, V.; Sudalai, A.; Daniel, T.; Srinivasan, K. Regioselective bromination of activated aromatic substrates with N-bromosuccinimide over HZSM-5. Tetrahedron Lett. 1994, 35 (38), 7055−7056. (b) Rahbæk, L.; Breinholt, J.; Frisvad, J. C.; Christophersen, C. Circumdatin A, B, and C: Three new benzodiazepine alkaloids isolated from a culture of the fungus Aspergillus ochraceus. J. Org. Chem. 1999, 64 (5), 1689−1692. (c) Zhang, Y.; Shibatomi, K.; Yamamoto, H. Lewis acid catalyzed highly selective halogenation of aromatic compounds. Synlett 2005, 2005 (18), 2837−2842. (2) (a) Xiao, J.; Lu, Z.; Li, Y. Carboxymethylcellulose-supported palladium nanoparticles generated in situ from palladium (II) carboxymethylcellulose: an efficient and reusable catalyst for Suzuki−Miyaura and Mizoroki−Heck reactions. Ind. Eng. Chem. Res. 2015, 54 (3), 790−797. (b) Miyaura, N.; Suzuki, A. PalladiumG

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research aromatics with N-iodosuccinimide in trifluoromethanesulfonic acid (NIC-CF3SO3H) via in situ generated superelectrophilic iodine (I) trifluoromethanesulfonate. J. Org. Chem. 1993, 58 (11), 3194−3195. (h) Ijam, M. J.; Al-Saleh, B. A.-L. Liquid Phase Bromination of Decane, Undecane, and Dodecane with N-Bromosuccinimide. Ind. Eng. Chem. Prod. Res. Dev. 1978, 17 (2), 144−148. (6) Mo, F.; Yan, J. M.; Qiu, D.; Li, F.; Zhang, Y.; Wang, J. GoldCatalyzed Halogenation of Aromatics by N-Halosuccinimides. Angew. Chem. 2010, 122 (11), 2072−2076. (7) (a) Li, B.; Gao, L.; Bian, F.; Yu, W. A new recoverable Au (III) catalyst supported on magnetic polymer nanocomposite for aromatic bromination. Tetrahedron Lett. 2013, 54 (9), 1063−1066. (b) Tang, R.-J.; Milcent, T.; Crousse, B., Regioselective Halogenation of Arenes and Heterocycles in Hexafluoroisopropanol. J. Org. Chem. 2018.83930 (8) (a) Hashmi, A. S. K. Gold-catalyzed organic reactions. Chem. Rev. 2007, 107 (7), 3180−3211. (b) Li, Z.; Brouwer, C.; He, C. Goldcatalyzed organic transformations. Chem. Rev. 2008, 108 (8), 3239− 3265. (c) Corma, A.; Leyva-Pérez, A.; Sabater, M. J. Gold-catalyzed carbon− heteroatom bond-forming reactions. Chem. Rev. 2011, 111 (3), 1657−1712. (d) Xiao, J.; Li, X. Gold α-Oxo Carbenoids in Catalysis: Catalytic Oxygen-Atom Transfer to Alkynes. Angew. Chem., Int. Ed. 2011, 50 (32), 7226−7236. (9) (a) Schwank, J.; Galvagno, S.; Parravano, G. Isotopic oxygen exchange on supported Ru and Au catalysts. J. Catal. 1980, 63 (2), 415−424. (b) Lin, S.; Vannice, M. Gold dispersed on TiO 2 and SiO 2: adsorption properties and catalytic behavior in hydrogenation reactions. Catal. Lett. 1991, 10 (1), 47−61. (c) Tanielyan, S. K.; Augustine, R. L. Effect of catalyst pretreatment on the oxidation of carbon monoxide over coprecipitated gold catalysts. Appl. Catal., A 1992, 85 (1), 73−87. (d) Tsunoyama, H.; Ichikuni, N.; Sakurai, H.; Tsukuda, T. Effect of electronic structures of Au clusters stabilized by poly (N-vinyl-2-pyrrolidone) on aerobic oxidation catalysis. J. Am. Chem. Soc. 2009, 131 (20), 7086−7093. (e) Cao, W.; Yu, B. A Recyclable Polystyrene-Supported Gold (I) Catalyst. Adv. Synth. Catal. 2011, 353 (11−12), 1903−1907. (f) Polshettiwar, V.; Luque, R.; Fihri, A.; Zhu, H.; Bouhrara, M.; Basset, J.-M. Magnetically recoverable nanocatalysts. Chem. Rev. 2011, 111 (5), 3036−3075. (10) (a) Polshettiwar, V.; Baruwati, B.; Varma, R. S. Nanoparticlesupported and magnetically recoverable nickel catalyst: a robust and economic hydrogenation and transfer hydrogenation protocol. Green Chem. 2009, 11 (1), 127−131. (b) Gawande, M. B.; Rathi, A. K.; Branco, P. S.; Nogueira, I. D.; Velhinho, A.; Shrikhande, J. J.; Indulkar, U. U.; Jayaram, R. V.; Ghumman, C. A. A.; Bundaleski, N.; Teodoro, O. M. N. D. Regio-and Chemoselective Reduction of Nitroarenes and Carbonyl Compounds over Recyclable Magnetic Ferrite Nickel Nanoparticles (Fe3O4 Ni) by Using Glycerol as a Hydrogen Source. Chem. - Eur. J. 2012, 18 (40), 12628−12632. (c) Liu, S.-Q.; Feng, L.R.; Xu, N.; Chen, Z.-G.; Wang, X.-M. Magnetic nickel ferrite as a heterogeneous photo-Fenton catalyst for the degradation of rhodamine B in the presence of oxalic acid. Chem. Eng. J. 2012, 203, 432− 439. (d) Nabid, M. R.; Bide, Y.; Niknezhad, M. Fe3O4−SiO2−P4VP pH-sensitive microgel for immobilization of nickel nanoparticles: An efficient heterogeneous catalyst for nitrile reduction in water. ChemCatChem 2014, 6 (2), 538−546. (11) (a) Okada, M.; Nakayama, Y.; Shiono, T. Heterogenization of an Anilinonaphthoquinone-Chelated Nickel Complex for Ethylene Polymerization Using Silica-Supported Modified Methylaluminoxane. Macromol. Chem. Phys. 2014, 215 (18), 1792−1796. (b) Bhunia, S.; Koner, S. Tethering of nickel (II) Schiff-base complex onto mesoporous silica: An efficient heterogeneous catalyst for epoxidation of olefins. Polyhedron 2011, 30 (11), 1857−1864. (c) Phan, N. T.; Brown, D. H.; Styring, P. A facile method for catalyst immobilisation on silica: nickel-catalysed Kumada reactions in mini-continuous flow and batch reactors. Green Chem. 2004, 6 (10), 526−532. (12) (a) Styring, P.; Grindon, C.; Fisher, C. M. A polymer-supported nickel (II) catalyst for room temperature Tamao−Kumada−Corriu coupling reactions. Catal. Lett. 2001, 77 (4), 219−225. (b) Poelmans, K.; Pinoie, V.; Verbruggen, I.; Biesemans, M.; Van Assche, G.; Deshayes, G.; Degée, P.; Dubois, P.; Willem, R. Catalytic properties of

cross-linked polystyrene grafted diorganotins in a model transesterification and the ring-opening polymerization of ε-caprolactone. Appl. Organomet. Chem. 2007, 21 (7), 504−513. (13) (a) Zohreh, N.; Hosseini, S. H.; Pourjavadi, A.; Bennett, C. Cross-linked poly (dimethylaminoethyl acrylamide) coated magnetic nanoparticles: a high loaded, retrievable, and stable basic catalyst for the synthesis of benzopyranes in water. RSC Adv. 2014, 4 (91), 50047−50055. (b) Shamim, T.; Paul, S. Silica Functionalized Cu (I) as a green and recyclable heterogeneous catalyst for the Huisgen 1, 3dipolar cycloaddition in water at room temperature. Catal. Lett. 2010, 136 (3−4), 260−265. (c) Taher, A.; Nandi, D.; Islam, R. U.; Choudhary, M.; Mallick, K. Microwave assisted azide−alkyne cycloaddition reaction using polymer supported Cu (I) as a catalytic species: a solventless approach. RSC Adv. 2015, 5 (59), 47275− 47283. (d) Moghaddam, F. M.; Ayati, S. E. Copper immobilized onto a triazole functionalized magnetic nanoparticle: a robust magnetically recoverable catalyst for “click” reactions. RSC Adv. 2015, 5 (5), 3894−3902. (14) (a) Jiang, J. X.; Su, F.; Trewin, A.; Wood, C. D.; Campbell, N. L.; Niu, H.; Dickinson, C.; Ganin, A. Y.; Rosseinsky, M. J.; Khimyak, Y. Z.; Cooper, A. I. Conjugated microporous poly (aryleneethynylene) networks. Angew. Chem., Int. Ed. 2007, 46 (45), 8574−8578. (b) Dong, Z.; Ye, Z. Heterogeneous palladium catalyst constructed with cross-linked hyperbranched poly (phenylacetylene) as polymer support: A reusable highly active ppm-level catalyst for multiple crosscoupling reactions. Appl. Catal., A 2015, 489, 61−71. (c) Saha, B.; Gupta, D.; Abu-Omar, M. M.; Modak, A.; Bhaumik, A. Porphyrinbased porous organic polymer-supported iron (III) catalyst for efficient aerobic oxidation of 5-hydroxymethyl-furfural into 2, 5furandicarboxylic acid. J. Catal. 2013, 299, 316−320. (d) Pourjavadi, A.; Hosseini, S. H.; Doulabi, M.; Fakoorpoor, S. M.; Seidi, F. Multilayer functionalized poly (ionic liquid) coated magnetic nanoparticles: highly recoverable and magnetically separable Brønsted acid catalyst. ACS Catal. 2012, 2 (6), 1259−1266. (e) Pourjavadi, A.; Hosseini, S. H.; Moghaddam, F. M.; Foroushani, B. K.; Bennett, C. Tungstate based poly (ionic liquid) entrapped magnetic nanoparticles: a robust oxidation catalyst. Green Chem. 2013, 15 (10), 2913−2919. (f) Pourjavadi, A.; Tajbakhsh, M.; Farhang, M.; Hosseini, S. H. Copper-loaded polymeric magnetic nanocatalysts as retrievable and robust heterogeneous catalysts for click reactions. New J. Chem. 2015, 39 (6), 4591−4600. (g) Maradur, S. P.; Jo, C.; Choi, D. H.; Kim, K.; Ryoo, R. Mesoporous Polymeric Support Retaining High Catalytic Activity of Polyoxotungstate for Liquid-Phase Olefin Epoxidation using H2O2. ChemCatChem 2011, 3 (9), 1435−1438. (h) Henthorn, D. B.; Peppas, N. A. Molecular simulations of recognitive behavior of molecularly imprinted intelligent polymeric networks. Ind. Eng. Chem. Res. 2007, 46 (19), 6084−6091. (15) (a) Li, Y.; Lan, J. Y.; Liu, J.; Yu, J.; Luo, Z.; Wang, W.; Sun, L. Synthesis of gold nanoparticles on rice husk silica for catalysis applications. Ind. Eng. Chem. Res. 2015, 54 (21), 5656−5663. (b) Chandra, D.; Jena, B. K.; Raj, C. R.; Bhaumik, A. Functionalized mesoporous cross-linked polymer as efficient host for loading gold nanoparticles and its electrocatalytic behavior for reduction of H2O2. Chem. Mater. 2007, 19 (25), 6290−6296. (16) Pourjavadi, A.; Hosseini, S. H.; Moghaddam, F. M.; Ayati, S. E. Copper loaded cross-linked poly (ionic liquid): robust heterogeneous catalyst in ppm amount. RSC Adv. 2015, 5 (38), 29609−29617. (17) Zohreh, N.; Hosseini, S. H.; Pourjavadi, A.; Bennett, C. Crosslinked poly(dimethylaminoethyl acrylamide) coated magnetic nanoparticles: a high loaded, retrievable, and stable basic catalyst for the synthesis of benzopyranes in water. RSC Adv. 2014, 4 (91), 50047− 50055. (18) Le, X.; Dong, Z.; Jin, Z.; Wang, Q.; Ma, J. Suzuki−Miyaura cross-coupling reactions catalyzed by efficient and recyclable Fe3O4@ SiO2@ mSiO2−Pd (II) catalyst. Catal. Commun. 2014, 53, 47−52. (19) Sharma, R. K.; Dutta, S.; Sharma, S. Nickel (ii) complex covalently anchored on core shell structured SiO 2@ Fe 3 O 4 nanoparticles: a robust and magnetically retrievable catalyst for direct H

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX

Article

Industrial & Engineering Chemistry Research one-pot reductive amination of ketones. New J. Chem. 2016, 40 (3), 2089−2101. (20) Pourjavadi, A.; Motamedi, A.; Marvdashti, Z.; Hosseini, S. H. Magnetic nanocomposite based on functionalized salep as a green support for immobilization of palladium nanoparticles: Reusable heterogeneous catalyst for Suzuki coupling reactions. Catal. Commun. 2017, 97, 27−31. (21) (a) Mostafalu, R.; Kaboudin, B.; Kazemi, F.; Yokomatsu, T. Narylation of amines: C−N coupling of amines with arylboronic acids using Fe 3 O 4 magnetic nanoparticles-supported EDTA−Cu (ii) complex in water. RSC Adv. 2014, 4 (90), 49273−49279. (b) Ghorbani-Choghamarani, A.; Norouzi, M. Synthesis and characterization of ionic liquid immobilized on magnetic nanoparticles: A recyclable heterogeneous organocatalyst for the acetylation of alcohols. J. Magn. Magn. Mater. 2016, 401, 832−840. (c) Zarnegaryan, A.; Moghadam, M.; Tangestaninejad, S.; Mirkhani, V.; Mohammdpoor-Baltork, I. A graphene oxide immobilized Cu (II) complex of 1, 2-bis (4-aminophenylthio) ethane: an efficient catalyst for epoxidation of olefins with tert-butyl hydroperoxide. New J. Chem. 2016, 40 (3), 2280−2286. (22) Kassaee, M.; Masrouri, H.; Movahedi, F. Sulfamic acidfunctionalized magnetic Fe3O4 nanoparticles as an efficient and reusable catalyst for one-pot synthesis of α-amino nitriles in water. Appl. Catal., A 2011, 395 (1−2), 28−33. (23) Chen, B.; Liu, Y.; Chen, S.; Zhao, X.; Yue, W.; Pan, X. Nitrogen-rich core/shell magnetic nanostructures for selective adsorption and separation of anionic dyes from aqueous solution. Environ. Sci.: Nano 2016, 3 (3), 670−681. (24) Huang, H.; Yao, J.; Chen, H.; Zeng, X.; Chen, C.; She, X.; Li, L. Facile preparation of halloysite/polyaniline nanocomposites via in situ polymerization and layer-by-layer assembly with good supercapacitor performance. J. Mater. Sci. 2016, 51 (8), 4047−4054.

I

DOI: 10.1021/acs.iecr.8b01179 Ind. Eng. Chem. Res. XXXX, XXX, XXX−XXX