Mg FERRITE AS A RECYCLABLE, MAGNETICALLY ...

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Knoevenagel condensation of arylaldehydes with 2,4-thiazolidinedione. The catalyst was prepared by simple co precipitation method and calcined at 550 °C.

South -Asian Journal of Multidisciplinary Studies (SAJMS) ISSN:2349-7858:SJIF:2.246:Volume 3 Issue 6

Ni – Mg FERRITE AS A RECYCLABLE, MAGNETICALLY SEPARABLE HETEROGENEOUS CATALYST FOR THE SYNTHESIS OF 5-ARYLIDENE-2,4-THIAZOLIDINEDIONES. Santosh Khillare 1, Machhindra Lande 1, Nitin Shinde2, Balasaheb Arbad 1* 1

Department of Chemistry, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad (M.S.), 431004, India. Fax: +91-240-2403335; Tel: +91-240-2403311

2

Shardabai Pawar Mahila Mahavidyalaya Shardanagar, Malegaon (Bk), Tal- Baramati, Dist – Pune (M.S.), 413115, India. Tel: 02112-254250 E-mail: [email protected]

ABSTRACT An eco-friendly Ni – Mg Ferrite solid heterogeneous catalyst has been employed for the Knoevenagel condensation of arylaldehydes with 2,4-thiazolidinedione. The catalyst was prepared by simple co precipitation method and calcined at 550 °C. The calcined sample was characterized by XRD, FT-IR, SEM and EDS, techniques. The catalytic activity results suggest that, the methodology adopted to offer significant improvements in the synthesis of substituted 5-arylidene-2,4thiazolidinediones with regards to short reaction times, high yields and the catalyst was successfully reused for three cycles without significant loss of activity. Keywords: Aromatic aldehyde, Ferrite, Heterogeneous catalysis, Metal oxide, One pot synthesis. 1. INTRODUCTION: Knoevenagel products viz. 5-arylidene derivatives of 2,4-thiazolidinedione have several potential activities such as pharmaceutical [1], aldose reductase inhibitors [2], fungistatic [3], antihistaminic [4], and also used in oral combination therapy in management of patients with type II diabetes [5]. There are several methods which have been used for the synthesis of 5-arylidene- 2,4thiazolidinediones by changing catalysts and reaction conditions such as sodium acetate [6], piperidinium acetate in DMF under microwave irradiation [7], KAl(SO4)2・12H2O in H2O at 90 0C [8], baker‟s yeast [9] and polyethylene glycol- 300 at 100–120 0C [10]. Recently, ionic liquids catalyzed synthesis of 5-arylidene-2,4-thiazolidinediones have also been reported [11,12]. Each of these methods have their own advantages but also have some disadvantages such as long reaction times, low to moderate yields, difficulty in recovery and reusability of the catalyst. Efforts are being made by the researchers are still in progress to improve the synthetic protocols of 5-arylidene-2,4thiazolidinediones, considering its importance in different fields. Present work is a part of our earlier efforts in the synthesis, characterization and applications of mixed metal oxides of transition metals in organic synthesis reactions. Recently, there has been an increased importance on the use of environmentally benign heterogeneous catalyst over conventional catalyst. Mixed metal oxides are inexpensive; easy to synthesize and recycle and effectively used to accelerate many organic reactions. Therefore in recent past, metal and mixed metal oxides specially ferrites have attracted much attention because of their many significant applications in various areas such as catalysis [13], to supports of catalysts [14], and can be used in biomedicine [15]. Especially, the magnetic properties of these materials makes possible the complete recovery by means of an external Copyright © Universal Multidisciplinary Research Institute Pvt Ltd

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magnetic field. In this paper it is planned to report the catalytic application of Ni-Mg Ferrite in synthesis of 5-arylidene-2,4-thiazolidinediones by simple and eco-friendly methodology. 2. MATERIALS AND METHODS: 2.1 MATERIALS The entire chemicals used were of synthesis grade reagents (Merck) and used as received. 2.2 PREPARATION OF CATALYST In a typical reaction, stoichiometric amounts of iron (III), nickel (II) and magnesium (II) nitrates were dissolved in deionized water. The pH of the solution was adjusted to 9 by the addition of aqueous ammonia, and then the solution was stirred vigorously for 4 h at 80oC and the precipitate so appeared was filtered, washed, and dried. Thus, the composite hydroxide of mixed metals so formed is calcined at 550oC for 5 hrs. After calcination NixMg1-xFe2O4 (Ni – Mg Ferrite) is formed. The catalytic material was synthesized by varying composition of Ni (II) and Mg (II) such as (a) x = 0.8, (b) x = 0.6, (c) x = 0.4 and (d) x = 0.2. 2.3 KNOEVENAGEL REACTION: A TYPICAL PROCEDURE In a typical reaction, aromatic aldehyde 1(5mmol) and 2,4-thiazolidinedione 2(5mmol) was added in a mixture of ethanol : water (1:1) (20 ml). To this a catalytic amount of synthesized Ni – Mg ferrite (0.2 gm) was added. The reaction mixture was refluxed (scheme 1). When reaction was completed as indicated by TLC, the catalyst was separated by magnet and dried for its next use and the reaction mixture was filtered. The crude product was purified by recrystalization from ethanol to give the corresponding pure compound 3. The pure products were characterized by IR, 1H- NMR and physical data (M.P.) and compound with those reported in the literature. 3a: IR (KBr) - 3129, 3030, 2786, 1772, 1737, 856 cm-1. 1HNMR (ä inDMSO) 8.53 (s, 1H), 7.88 (s, 1H), 7.27 (m, 5H). 3b: IR (KBr)- 3366, 3045, 2769, 1838, 1732, 868 cm-1. 1HNMR (ä inDMSO) 8.54 (s, 1H), 7.86 (s, 1H), 7.40 (d, 2H), 7.28 (d, 2H), 2.42 (s, 3H). 3. RESULTS AND DISCUSSION: 3.1 CHARACTERIZATION OF SYNTHESIZED FERRITE The X-ray diffraction (XRD) patterns of the catalysts were recorded on a Bruker D8 advance Xray diffractometer using Cu Kα radiation with a wavelength of 0.154056 nm. To study the surface morphology of synthesized ferrite scanning electron microscopy (SEM) analyses were carried out with a JEOL JSM-6330 LA operated at 20.0kV and 1.0nA. The elemental composition of the metals in the synthesized Ni – Mg ferrite was examined using an energy dispersive spectrophotometer (EDS). BET surface area has been measured by means of N2 adsorption at 77.68 K performed on a micromeritics ASAP 2010 and temperature programmed desorption of ammonia (NH3-TPD) measurements were carried out on a micromeritics chemisoft TPx V1.02. 3.2 XRD ANALYSIS. The powder X-ray diffraction pattern of Ni - Mg ferrite calcined at 550 oC for 5 hrs is shown in Figure 1. While analyzing XRD pattern, it is observed that there are slight differences between the relative intensities and width of reflexes, which indicates the differences of crystallite size. The sharp peaks represents that all Ni-Mg ferrites are crystalline in nature. The highly intense and sharp peaks are present at 2Ө =38, 41, 44.20, 50.68, 66.39 from the reflection planes indexed as (220) (311) (431) (400) (620) respectively indicates the cubic structure of Ni-Mg ferrites. The X-ray diffraction pattern were material with standard data (ICPDS PDF card no 00-008-0234) also confirms the formation of cubic Ni - Mg ferrite. The lattice parameter „a‟ of Ni-Mg ferrites are given in Table 1 which are in close agreement with standard data (8.34Ao) [16]. The size of crystallite was evaluated by measuring the FWHM of the Copyright © Universal Multidisciplinary Research Institute Pvt Ltd

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most intense peak (311) mentioned in Table 1. Using the Debye Scherrer‟s formula [17] the mean crystalline size of the sample was calculated and that lies in the range of 28-45 nm. 3.3 FT-IR ANALYSIS: The FT –IR spectra of series of Ni-Mg ferrites using dry KBr as a standard reference lies in the range of 4000-500 cm-1 are shown in Figure 2. From the IR spectrum, it is observed that in each sample (a-d) the broad peak is present in the range 3200-3500cm-1 which is due to the hydroxyl group adsorbed on the surface of catalyst, similarly in all the cases the peak in the range of 1500-1600 and 1380- 1460 cm1 is due to the deformation of the surface hydroxyl groups [18]. In the range from 1000-400, two main metal-oxygen bands are seen in IR spectra of all samples. The higher one generally observed in the range 600-550cm-1 is caused by the stretching vibrations of the tetrahedral metal-oxygen bond (MtetraO) and the lowest band usually observed in the range 450-400cm-1 is caused by the metal oxygen vibrations in the octahedral sites.(Mocta-O) [19]. 3.4 SEM AND EDS ANALYSIS The surface morphology of the synthesized Ni - Mg Ferrite is studied by scanning electron micrograph and are shown in Figure 3. The SEM micrograph of Ni-Mg ferrite catalyst shows agglomeration of particles and irregular in shape. The as prepared samples have spongy and fragile network structure with voids and pores. EDS pattern obtained for all the samples which gives the elemental composition in the samples. Table 2 shows the elemental composition of Ni - Mg Ferrite samples. The compound shows the presence of Ni, Mg, Fe and O. 3.5 BET AND NH3-TPD ANALYSIS NH3-TPD measurements were carried out by i) preheating 200 mg sample to 10oC/min heating rate in helium with flow rate 20 cm3/min. ii) adsorption of NH3 at room temperature. iii) desorption of adsorbed NH3 with an heating rate 10oC/min from room temperature to 550oC. NH3-TPD curve of catalytically active sample Ni0.8Mg0.2Fe2O4 calcined at 550°C is shown in figure 4. The acidity of sample Ni0.2Mg0.8Fe2O4 was detected by temperature programmed desorption of ammonia. Total acidity of NiMg ferrite is found to be 0.3763 mmol/g. BET theory aims to explain the physical adsorption of gas molecules on solid surface and serves as the basis for the measurement of the specific surface area of a catalytic material. The calculated BET surface area of Ni-Mg ferrite is 1.6665 m2/g. 3.6. CATALYTIC ACTIVITY RESULTS The synthesis of 5-arylidene derivatives of 2,4-thiazolidinedione via condensation of arylaldehydes with 2,4-thiazolidinedione catalyzed by Ni - Mg Ferrite, is shown in scheme 1. The effect of solvents and the addition of water on the Knoevenagel condensation reaction is given in Table 3. These results shows that the reaction in aprotic solvents such as Toluene, CH2Cl2, THF and CH3CN gives only 30-45% conversion after 3 h while the reaction in alcoholic and non polar solvents gives moderate yield Table 3. However, the addition of water as co-solvent to the alcoholic solvents significantly enhanced the rate of reaction with excellent yield. The reaction gives maximum yield i.e. up to 90%, when the ratio of ethanol and water was 1:1. Thus the ratio of water to ethanol played vital role in the Ni-Mg Ferrite catalyzed Knoevenagel condensation reaction. The possibility of recycling the catalyst was examined using the reaction of 4-methyl benzaldehyde and 2,4-thiazolidinedione under the optimized conditions. After completion of reaction the catalyst was separated by putting external magnet, washed with ethyl acetate, dried at 60oC and activated at 120oC for 1hr before the next catalytic run. During washing with the solvent, it was clearly observed that there was no loss of catalyst. In present work, it is observed that Ni-Mg Ferrite catalyst shows excellent to good reactivity with better yield even after four cycles for the same reaction. The results are listed in table 4. Copyright © Universal Multidisciplinary Research Institute Pvt Ltd

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Using the optimized reaction conditions, the common applicability of Ni-Mg Ferrite catalyst with 2,4-thiazolidinedione and aldehydes and containing electron withdrawing or donating substituents is investigated and summarized in Table 5. The Ni-Mg Ferrite catalyzed knoenenagel condensation reaction gives good results for a wide range of substituted aldehydes such as NO2, Me, Cl, OMe, and OH. The electron deficient aldehydes showed excellent reactivity with 2,4-thiazolidinedione and gaves high yields within short reaction times. Electron rich aldehydes required longer reaction time to give results. Both electron rich and electron deficient aldehydes gave products in good to excellent yield than ortho substituted aldehydes which gaves lower yields. 4. CONCLUSIONS: We have developed a simple protocol for preparing a magnetically separable and recyclable NiMg Ferrite catalyst by co-precipitation method and characterized using various techniques and confirmed its high activity in the condensation of various aldehydes and 2,4-thiazolidinedione. Moreover, we have also shown that the catalyst can be reused at least 5 times without loss of activity. Among the synthesized ferrites Ni0.8Mg0.2Fe2O4, shows better catalytic activity for the synthesis of 5arylidene-2,4-thiazolidinediones. 5. ACKNOWLEDGEMENT: We are grateful to UGC New Delhi for providing financial assistance through SAP-DRS1 and to the Head, Department of Chemistry, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad-431004 (MS), India for providing the laboratory facility. 6. References: [1] Malamas M. S., Sredy J., Gunawan I., (2000) “New azolidinediones as inhibitors of protein tyrosine phosphatase lb with antihyperglycemic properties,” Journal of Medicinal Chemistry, 43: 995–1010. [2] Bruno G., Costantino L., Curinga C., (2002) “Synthesis and aldose reductase inhibitory activity of 5-arylidene-2,4-thiazolidinediones,” Bioorganic and Medicinal Chemistry, 10: 1077–1084. [3] Ottan R., MacCari R., Barreca M. L., (2005) “5-arylidene-2-imino-4-thiazolidinones: design and synthesis of novel anti-inflammatory agents,” Bioorganic and medicinal chemistry, 13: 4243-4252. [4] Previtera T., Vigorita M. G., Bisila M.., Orsini F., Benetolla F. and Bombieri G., (1994) “3,3Di1,3-thiazolidene-4-one system, VI: structural and conformational studies on configurational isomers with antihistaminic activity,” European Journal of Medicinal Chemistry, 29: 317-324. [5] Saltiel, A. R.., Olefsky J. M., (1996) “thiazolidinediones in the treatment of insulin resistance and type II diabetes,” Diabetes 45: 1661-1669. [6] Wrobleski M. L., Reichard G. A., Paliwal S., Shah S., Tsui H. C., Duffy R. A., Lachowicz J. E., Morgan C. A., Varty G. B., and Shih N. Y., (2006) “Cyclobutane derivatives as potent NK1 selective antagonists,” Bioorganic and Medicinal Letters 16: 3859-3863. [7] Mahalle S., Ligampalle D., and Mane R., (2009) “Microwave-assisted synthesis of some 2,4thiazolidinedione derivatives,” Heteroatom Chemistry, 20: 151–156. [8] Shelke K. F., Sapkal S. B., Kakade G. K., Sadaphal S. A., Shingate B. B., Shingare M. S., (2010) “Alum catalyzed simple and efficient synthesis of 5-arylidene-2,4-thiazolidinedione in aqueous media,” Green Chemistry Letters and Reviews, 3: 17–21. [9] Pratap U. R., Jawale D. V., Waghmare R. A., Lingampalle D. L., and Mane R. A., (2011) “Synthesis of 5-arylidene-2,4-thiazolidinediones by Knoevenagel condensation catalyzed by baker‟s yeast,” New Journal of Chemistry, 35: 49–51.

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[10]

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[15] [16] [17] [18] [19]

Mahalle S. R., Netankar P. D., Bondge S. P., and Mane R. A., (2008). “An efficient method for Knoevenagel condensation: a facile synthesis of 5-arylidenyl 2,4-thiazolidinedione,” Green Chemistry Letters and Reviews, 1: 103–106. Shelke K. F., Sapkal S. B., Madje B. R., Shingate B. B., Shingare M.S., (2009) “Ionic liquid promoted an efficient synthesis of 5-arylidene-2,4-thiazolidinedione,” Bulletin of the Catalysis Society of India, , 8: 30–34. Jawale D. V., Pratap U. R., Lingampalle D. L., Mane R. A., (2011) “Dicationic ionic liquid mediated synthesis of 5-arylidine 2,4-thiazolidinedione,” Chinese Journal of Chemistry, 29: 942– 946. Borhade S. R., Waghmode S. B., (2011) “Studies on Pd/NiFe2O4 catalyzed ligand free Suzuki reaction in aqueous phase: synthesis of biaryls terphenyls and polyaryls,” Beilstein J. of Org. Chem. 7: 310-319. Jianming Liu, Xingao Peng, Wei Sun, Yongwei Zhao, Chungu Xia (2008) “Magnetically separable Pd catalyst for carbonylative sonogashira coupling reaction for the synthesis of α,βalkynyl ketones,” OrganicLetters 10: 2933-2936. Ito A., Shinkai M., Honda H., Kobayashi T., (2005) “Medical application of functionalized magnetic nanoparticles,” J. Biosci.and Bioeng., 100: 1-11. smit J, wijn HPJ, eds.(1959). ferrite The Netherlands: Philips technical library 137. Cullity B. D., 2nd ed (1978).Elements of X-ray diffraction. Addison-Wesley, California 102 A. Lagashetty, V. havanoor, S. Basavaraja, (2007) “Microwave assisted route for synthesis of nanosized metal oxides,” sci Technol. Adv .mater. 8: 484-493. Waldron R.D. (1955) “Infrared spectra of ferrites,” phys.Rev. 99: 1727.

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Figure Captions: 1. Figure 1. XRD pattern of series of Ni – Mg Ferrite (NixMg1-xFe2O4) where, (a) x=0.8, (b) x=0.6, (c) x=0.4 and (d) x=0.2 calcined at 550oC. 2. Figure 2. FT-IR spectra of Ni-mg ferrite (NixMg1-xFe2O4) where, (a) x = 0.8, (b) x = 0.6, (c) x = 0.4, (d) x=0.2 calcined at 550 oC. 3. Figure 3 SEM images of NixMg1-xFe2O4 (a) x = 0.8 (b) x = 0.6 (c) x = 0.4 (d) x=0.2 4. Figure 4. NH3-TPD curve for TCD signal (a. u.) vs. Temperature oC of the sample Ni0.8Mg0.2Fe2O4 5. Scheme 1. Synthesis of 5-arylidene, 2,4-thiazolidinediones catalyzed by Ni-Mg Ferrite solid heterogeneous catalyst. Table Captions: 1. Table 1. XRD analysis of Ni-Mg Ferrite (NixMg1-xFe2O4) samples. 2. Table 2. Elemental composition of Ni-Mg Ferrite (NixMg1-xFe2O4) sample. 3. Table 3. Synthesized Ni – Mg Ferrite catalyzed Knoevenagel condensation of Benzaldehyde, 2,4-thiazolidinediones in different solventsa. 4. Table 4. Recycle and reusability of Ni0.8Mg0.2Fe2O4a 5. Table 5. Synthesized Ni-Mg Ferrite catalyzed knoevenagel reaction of aromatic aldehydes and 2,4-thiazolidinediones a.

Figure 1. XRD pattern of series of Ni – Mg Ferrite (NixMg1-xFe2O4) where, (a) x=0.8, (b) x=0.6, (c) x=0.4 and (d) x=0.2 calcined at 550oC. Copyright © Universal Multidisciplinary Research Institute Pvt Ltd

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Figure 2. FT-IR spectra of Ni-mg ferrite (NixMg1-xFe2O4) where, (a) x = 0.8, (b) x = 0.6, (c) x = 0.4, (d) x=0.2 calcined at 550 oC.

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Figure 3 SEM images of NixMg1-xFe2O4 (a) x = 0.8 (b) x = 0.6 (c) x = 0.4 (d) x=0.2

Figure 4. NH3-TPD curve Ni0.8Mg0.2Fe2O4 calcined at 5500C Copyright © Universal Multidisciplinary Research Institute Pvt Ltd

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CHO

O

O NH

+

1

O

O Reflux EtOH : Water

S R

NH

0.2 g Ni-Mg Ferrite

S

R

2

3a -h

Scheme 1. Synthesis of 5-arylidene, 2,4-thiazolidinediones catalyzed by Ni-Mg Ferrite solid heterogeneous catalyst.

Table 1. XRD analysis of Ni-Mg Ferrite (NixMg1-xFe2O4) samples. Sample

Crystallite size (nm)

Lattice constant (Ao)

x = 0.8

45.13

8.4412

x = 0.6

36.38

8.4412

x = 0.4

28.05

8.4412

x = 0.2

40.19

8.4412

Table 2. Elemental composition of Ni-Mg Ferrite (NixMg1-xFe2O4) samples. Mass % Catalyst

Total Ni

Mg

Fe

O

X = 0.8

18.31

2.01

47.09

32.59

100

X = 0.6

13.96

3.65

49.53

32.86

100

X = 0.4

9.87

6.95

51.25

31.93

100

X = 0.2

4.93

9.03

54.19

31.85

100

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Table 3. Synthesized Ni - Mg Ferrite catalyzed Knoevenagel condensation of Benzaldehyde, 2,4thiazolidinediones in different solventsa. Entry

Solvent

Isolated Yieldb %

1

EtOH

55

2

CH3CN

40

3

Toluene

30

4

THF

45

5

CH2Cl2

35

6

H2O

50

7

EtOH:H2O

90

8

CH3CN:H2O

65

a

Reaction condition: benzaldehyde (5mmol) and 2,4-thiazolidinediones (5mmol), Ni-Mg Ferrite 0.2

gm, 20 ml solvent, refluxed 180 min. b Isolated Yield Table 4. Recycle and reusability of Ni0.8Mg0.2Fe2O4a Entry

Ni-Mg Ferrite

Time (min)

Isolated Yieldb %

1

Ni0.8Mg0.2Fe2O4

180

90

2

Ni0.8Mg0.2Fe2O4

180

90

3

Ni0.8Mg0.2Fe2O4

180

88

4

Ni0.8Mg0.2Fe2O4

180

86

5

Ni0.8Mg0.2Fe2O4

180

86

Reaction condition: 4-CH3benzaldehyde (5mmol) and 2,4-thiazolidinediones (5mmol), Ni-Mg Ferrite 0.2 gm, EtOH:H2O as solvent 20 ml, stirred 180 min. b Isolated Yield

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Table 5. Synthesized Ni-Mg Ferrite catalyzed knoevenagel reaction of aromatic aldehydes and 2,4thiazolidinediones a. Time

Isolated Yieldb

M. P. (oC)

(min)

(%)

Found

Reported

Entry

R

3a

H

180

83

240-242

241-242 [12]

3b

4-CH3

180

90

222-224

225-226 [12]

3c

4-NO2

200

75

184-186

183-184 [8]

3d

4-OCH3

175

90

215-217

218-219 [12]

3e

4-Cl

170

85

275-277

278-280 [8]

3f

4-OH

180

85

282-284

282-285 [8]

3g

3-NO2

200

80

183-185

183-184 [8]

3h

2-OH

210

75

276-278

278-280 [8]

a

Reaction condition: aromatic aldehyde (5mmol) and 2,4-thiazolidinediones (5mmol), Ni-Mg Ferrite

0.2 gm, 20 ml water as solvent, stirred. bIsolated Yield,

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