Chinese Chemical Letters  2016, Vol.27 Issue (01): 114-118   PDF    
Rapid and mild synthesis of quinazolinones and chromeno[d]pyrimidinones using nanocrystalline copper(I) iodide under solvent-free conditions
Shahrzad Abdolmohammadi , Samira Karimpour    
Department of Chemistry, Faculty of Science, East Tehran Branch, Islamic Azad University, PO Box 33955-163 Tehran, Iran
Abstract: This paper describes a very simple, efficient synthesis of quinazolinones and chromeno[d]pyrimidinones from the reaction of aryl aldehydes, urea/thiourea and active methylene compounds(dimedone/4-hydroxycoumarin) using nano-sized CuI particles under solvent-free conditions. The highlights of this new method are based on using an effective and recyclable catalyst, affording high yields of products, mild reaction conditions, facile work-up and purification.
Key words: Chromeno[d]pyrimidinones     Copper(I) iodide nanoparticles     Quinazolinones     Solvent-free conditions    
1. Introduction

The quinazolinone moiety is found,as alterative in a wide variety of biologically active compounds which can be used as hypnotic/sedative drugs for treatment of cancer [1]. Furthermore, quinazolinone derivatives are of interest because they exhibit a broad spectrum of biological properties,such as analgesic [2],antiinflammatory [3],antimicrobial and anti-tubercular [4, 5],anti-HIV [6],antimalarial and antihistamine [7]. Chromenes are also an important class of nitrogen containing heterocycles,which possess a range of diverse pharmacological properties,such as antioxidant [8, 9],anticancer [10, 11, 12, 13],antimicrobial [14, 15, 16, 17],hypotensive [18], and local anesthetic [19]. In addition,they have been used as cognitive enhancers [20, 21] in the treatment of neurodegenerative diseases,including Alzheimer’s disease [22] and schizophrenia [23].

Recent reports reveal that the utility of nanostructured metal salts,as efficient heterogeneous catalysts,have emerged as a powerful synthetic tools for the synthesis of many organic compounds [24, 25, 26, 27, 28, 29, 30]. Copper(I) iodide nanoparticles (CuI NPs) as a Lewis acid catalyst,has attracted intense interest due to its unique and improved properties [31, 32, 33, 34, 35, 36, 37, 38].

Thus,the synthesis of heterocycles with a quinazolinone or chromene framework is of particular importance to chemists and, hence,various methods have been developed for the synthesis of these compounds as described in the literature [39, 40, 41, 42, 43]. Although, most of these procedures offer several advantages,there are also related disadvantages,such as longer reaction times,unsatisfactory yields,harsh reaction conditions and use of high cost or toxic catalysts. To the best of our knowledge,however,no reports to date have revealed the synthesis of these compounds using a CuI NPs catalyst. With this in mind,the central focus of the present article is to investigate the role of nano-sized CuI particles as an inexpensive,readily prepared,recoverable and high yielding heterogeneous catalyst for the synthesis of quinazolinones (4) and chromeno[d]pyrimidinones (6) via a condensation reaction of aryl aldehydes 1,urea/thiourea 2 and active methylene compounds including dimedone (3) or 4-hydroxycoumarin (5) under solvent-free conditions (Scheme 1).

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Scheme 1.Synthesis of quinazolinone and chromeno[d]pyrimidinone derivatives.
2. Experimental 2.1. Materials and methods

All of the chemical materials used in this work were purchased from Merck or Sigma-Aldrich and used without further purification. Melting points were determined on an Electrothermal 9100 apparatus and are uncorrected. IR spectra were obtained on an ABB FT-IR (FTLA 2000) spectrometer. The 1H NMR spectra were recorded on a Bruker DRX-400 AVANCE at 400 MHz,using TMS as internal standard and DMSO-d6 as solvent. Elemental analyses were carried out using a Heraeus CHN rapid analyzer.

2.2. General procedure for preparation of compounds 4a-h and 6a-f

A mixture of aryl aldehyde (1 mmol),urea/thiourea (1.2 mmol), active methylene compound (dimedone/4-hydroxycoumarin) (1 mmol) and CuI NPs (1.9 mg,10 mol%) was stirred at 70 ℃ for appropriate times. After completion of the reaction,indicated by TLC,the reaction mixture was diluted with DMF (5 mL) and centrifuged for 5 min at 2000-3000 rpm,to separate the catalyst by filtration which then was washed with EtOH,and dried under vacuum for several hours. The filtrate was then poured into icecold water (10 mL) to give a solid precipitate,which was filtered, washed with water and recrystallized from EtOH to generate the pure product.

7,7-Dimethyl-4-phenyl-4,6,7,8-tetrahydro-2,5(1H,3H)-quinazolinedione (4a): Yield 254 mg (94%). White powder. M.p. 285- 287 ℃. IR (KBr,cm-1): νmax 3333,3254,2960,1706,1678,1611, 1474,1364. 1H NMR (400 MHz,DMSO-d6): δ 0.98 (s,3H,CH3),1.09 (s,3H,CH3),2.21 (q,2H,J = 16.0 Hz,CH2),2.38 (q,2H,J = 16.7 Hz, CH2),5.29 (d,1H,J = 2.8 Hz,CH),7.27 (m,5H,HAr),7.46 (s,1H,NH), 9.35 (s,1H,NH). Anal. Calcd. for C16H18N2O2 (270.33): C 71.09,H 6.71,N 10.36; found: C 70.86,H 6.61,N 10.58.

7,7-Dimethyl-4-(2-chlorophenyl)-4,6,7,8-tetrahydro- 2,5(1H,3H)-quinazolinedione (4b): Yield 283 mg (93%). White powder. M.p. 269-270 ℃. IR (KBr,cm-1): νmax 3427,3211,1680, 16=,1619,1447,1370. 1H NMR (400 MHz,DMSO-d6): δ 0.78 (s, 3H,CH3),0.83 (s,3H,CH3),1.85 (m,2H,CH2),2.16 (m,2H,CH2), 5.33(s,1H,CH),7.12 (m,4H,HAr),7.51 (s,1H,NH),9.29 (s,1H,NH). Anal. Calcd. for C16H17ClN2O2 (304.78): C 63.05,H 5.62,N 9.19; found: C 63.23,H 5.77,N 9.38.

7,7-Dimethyl-4-phenyl-2-thioxo-2,3,4,6,7,8-hexahydro-5(1H)- quinazolinone (4f): Yield 263 mg (92%). White powder. M.p. 281- 283 ℃. IR (KBr,cm-1): νmax 3280,3204,1711,1620,1572,1451, 1383. 1H NMR (400 MHz,DMSO-d6): δ 0.90 (s,3H,CH3),1.02 (s,3H, CH3),2.21 (m,2H,CH2),2.42 (m,2H,CH2),5.23 (s,1H,CH),7.26 (m, 3H,HAr),7.33 (m,2H,HAr),9.70 (s,1H,NH),10.61 (s,1H,NH). Anal. Calcd. for C16H18N2OS (286.39): C 67.10,H 6.33,N 9.78; found: C 66.91,H 6.41,N 9.56.

7,7-Dimethyl-4-(4-methylphenyl)-2-thioxo-2,3,4,6,7,8-hexahydro- 5(1H)-quinazolinone (4h): Yield 273 mg (91%). White powder. M.p. 279-280 ℃. IR (KBr,cm-1): νmax 3307,3184, 1639,1565,1431,1344. 1H NMR (400 MHz,DMSO-d6): δ 0.91 (s,3H,CH3),1.04 (s,3H,CH3),2.08 (m,2H,CH2),2.20 (s,2H,CH2), 2.26 (s,3H,CH3),5.17 (s,1H,CH),7.13 (m,4H,HAr),9.63 (s,1H, NH),10.56 (s,1H,NH). Anal. Calcd. for C17H20N2OS (300.42): C 67.97,H 6.71,N 9.32; found: C 67.61,H 6.53,N 9.23.

4-Phenyl-3,4-dihydro-2H-chromeno[4, 3, d]pyrimidine- 2,5(1H)-dione (6a): Yield 278 mg (95%). White powder. M.p. 162- 163 ℃. IR (KBr,cm-1): νmax 3404,2952,2677,2344,1673,1439, 1391. 1H NMR (400 MHz,DMSO-d6): δ 6.31 (s,1H,CH),7.38 (m,9H, HAr),7.90 (s,1H,NH),8.03 (s,1H,NH). Anal. Calcd. for C17H12N2O3 (292.29): C 69.86,H 4.14,N 9.58; found: C 69.64,H 3.96,N 9.69.

4-(Dimethylaminophenyl)-3,4-dihydro-2H-chromeno[4,3- d]pyrimidine-2,5(1H)-dione (6c): Yield 322 mg (96%). Brick-red powder. M.p. 242-244 ℃. IR (KBr,cm-1): νmax 3412,3115,2904, 2716,2584,1685,1606,1560,1536,1441,1359. 1H NMR (400 MHz,DMSO-d6): δ 3.17 (s,6H,CH3),6.50 (s,1H,CH),7.30 (m,8H,HAr),7.84 (s,1H,NH),8.01 (s,1H,NH). Anal. Calcd. for C19H17N3O3 (335.36): C 68.05,H 5.11,N 12.53; found: C 68.21,H 5.24,N 12.60.

4-(4-Methoxyphenyl)-2-thioxo-1,2,3,4-tetrahydro-5H-chromeno[ 4,3-d]pyrimidine-5-one (6f): Yield 315 mg (93%). White powder.M.p. 265-267 ℃. IR (KBr,cm-1): νmax 3389,3102,1953, 1705,1622,1605,1578,1491,1450,1326. 1H NMR (400MHz, DMSO-d6): δ 3.77 (s,3H,OCH3),6.44 (s,1H,CH),6.94 (m,8H, HAr),8.04 (s,1H,NH),8.07 (s,1H,NH). Anal. Calcd. for C18H14N2O3S (338.38): C 63.89,H 4.17,N 8.28; found: C 63.71,H 4.07,N 8.11.

3. Results and discussion

In continuation of our research program towards highly expedient methodologies for the synthesis of heterocyclic compounds using nanostructured catalysts,we have found that CuI nanoparticles (CuI NPs) are suitable for the preparation of quinazolinones 4(a-h) and chromeno[d]pyrimidinones 6(a-f) by the three-component coupling reaction of aryl aldehydes,urea/thiourea and active methylene compounds (dimedone/4- hydroxycoumarin) at 70 ℃ under solvent-free conditions.

In a preliminary study,CuI NPs were prepared according to the published procedure of Salavati-Niasari et al. [44]. The crystalline structure and purity of the CuI NPs was confirmed from XRD analyses. The XRD results (Fig. 1) confirmed the presence of CuI NPs with high crystallinity and a cubic structure with space groupings of F-43m and cell constants 6.0545A˚ (JCPDS 82-2111 of CuI for confirmation). The SEM image of CuI NPs is presented in Fig. 2 which shows triangular shapes with a size range of 30-40 nm of nanoparticles. The TEM image of CuI NPs is also shown in Fig. 3.

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Fig. 1.XRD pattern of the synthesized CuI NPs.

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Fig. 2.SEM image of the synthesized CuI NPs.

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Fig. 3.TEM image of the synthesized CuI NPs.

We then studied on the optimization of the reaction conditions using a model reaction of 2-chlorobenzaldehyde (1b),urea (2b) and dimedone (3) to afford the corresponding product (4b) under various reaction conditions. The results are summarized in Table 1. First,we checked the efficiency of CuI NPs as a heterogeneous catalyst using different amounts of CuI NPs. The results in Table 1 show that using just 10 mol% of catalyst affected the efficiency of the reaction (Table 1,entries 1-4). In investigating the effect of the reaction media,several solvents were also examined. Thus,the best yield of product was obtained under solvent-free conditions (Table 1,entries 3 and 5-7). To determine the optimized reaction temperature,the model reaction was carried out at different temperatures. It was observed that the optimal temperature of 70 ℃ was best and higher temperatures up to 80 and 100 ℃ did not improve the yield of product (Table 1,entries 3 and 8-10). During optimization,we thenexplored the role ofmole ratio of the reactants and determined,that the present method is effective for large-scale synthesis as well as routine scale (Table 1,entries 3 and 11).

Table 1
Synthesis of 4b by the reaction of 2-chlorobenzaldehyde, urea and dimedone under different conditions.

To determine the utility of this new procedure,we examined some substituted benzaldehydes for the reaction with urea/ thiourea and active methylene compounds,including dimedone or 4-hydroxycoumarin,to obtain desired products under optimized conditions (Table 2). The isolated compounds 4(a-h) and 6(a-f) were characterized by IR and 1H NMR spectroscopic data and also by elemental analyses. The analytical,spectroscopic and physical data are in good agreement with those described in the literature. Selected spectroscopic data are reported in Section 2.2.

Table 2
CuI NPs catalyzed syntheses of quinazolinones 4(a–h) and chromeno[d]pyrimidinones 6(a–f) under solvent-free conditions.

A plausible mechanism for the formation of product 4 is given in Scheme 2. It is feasible that CuI NPs participates in two following catalytic cycles. The initial event is the formation of copper oxonium salt 7 which then undergoes a Knoevenagel condensation with dimedone 3,to generate alkene 9 via intermediate 8. The urea/thiourea 2 then adds to alkene 9 to produce the Michael adduct 10. Further cyclization of 10 gives product 4,after dehydration. The formation of product 6 is likely to occur via a tandem Knoevenagel-Michael condensation as that was explained in Scheme 2,for the formation of product 4.

Moreover,we evaluated separation,isolation and recycling of the CuI NPs catalyst,which was successfully recycled as mentioned in Section 2.2 and reused several times in the model reaction with no significant loss of activity (Fig. 4). From the XRD patterns of the second and third recycled catalyst reuse,the character of CuI in the cubic phase is not changed and could be compared to the original one (Fig. 5).

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Scheme 2.Proposed mechanism for the reaction of aryl aldehyde, urea/thiourea and dimedone as active methylene compound, catalyzed by CuI NPs.

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Fig. 4.Reuse of CuI NPs for the synthesis of 4b.

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Fig. 5.XRD patterns of (a) original catalyst, (b) 2nd recycled catalyst use, and (c) 3rd recycled catalyst use.
4. Conclusion

In summary,we have developed an efficient and less wasteful manufacturing method for the synthesis of some of quinazolinone and chromeno[d]pyrimidinone derivatives from aryl aldehydes,urea/thiourea and active methylene compounds, including dimedone or 4-hydroxycoumarin,using CuI NPs as reusable and inexpensive heterogeneous catalysts under solvent- free conditions. This new catalytic method has several advantages including high yields of products,short reaction time, simple operation and use of reusable,non-toxic and inexpensive catalyst.

Acknowledgment

Shahrzad Abdolmohammadi is pleased to acknowledge the financial support from the Research Council of East Tehran Branch, Islamic Azad University.

References
[1] K. Chen, K. Wang, A.M. Kirichian, et al., In silico design, synthesis, and biological evaluation of radioiodinated quinazolinone derivatives for alkaline phosphatasemediated cancer diagnosis and therapy, Mol. Cancer Ther. 5(2006) 3001-3013.
[2] M.M. Aly, Y.A. Mohamed, W.M. Basyouni, Synthesis of some new 4(3H)-quinazolinone-2-carboxaldehyde thiosemicarbazones and their metal complexes and a study on their anticonvulsant, analgesic, cytotoxic and antimicrobial activities-part-1, Eur. J. Med. Chem. 45(2010) 3365-3373.
[3] A. Kumar, C.S. Rajput, Synthesis and anti-inflammatory activity of newer quinazolin-4-one derivatives, Eur. J. Med. Chem. 44(2009) 83-90.
[4] M. Kidwai, S. Saxena, M.K.R. Khan, S.S. Thukral, Synthesis of 4-aryl-77-dimethyl-1,2,3,4,5,6,7,8-octahydroquinazoline-2-one/thione-5-one derivatives and evaluation as antibacterials, Eur. J. Med. Chem. 40(2005) 816-819.
[5] R.Dahiya,A.Kumar,R.Yadav,Synthesis andbiologicalactivityofpeptide derivatives of iodoquinazolinones/nitroimidazoles, Molecules 13(2008) 958-976.
[6] V. Alagarsamy, U.S. Pathak, S.N. Pandaya, D. Sriram, E. De Clercq, Anti-HIV and anti bacterial activities of some disubstituted quinazolones and their bio-isoster disubstituted thienopyrimidones, Indian J. Pharm. Sci. 66(2000) 433-437.
[7] M.M. Ghorab, S.M.A. Gawad, M.S.A. El-Gaby, Synthesis and evaluation of some new fluorinated hydroquinazoline derivatives as antifungal agents, Farmaco 55(2000) 249-255.
[8] L. Alvey, S. Prado, V. Huteau, et al., A new synthetic access to furo[3,2-f]chromene analogues of an antimycobacterial, Bioorg. Med. Chem. 16(2008) 8264-8272.
[9] T. Symeonidis, M. Chamilos, J. Hadjipavlou-Litina, M. Kallitsakis, E. Litinas, Synthesis of hydroxycoumarins and hydroxybenzo[f]-or[h]coumarins as lipid peroxidation inhibitors, Bioorg. Med. Chem. Lett. 19(2009) 1139-1142.
[10] J.L. Wang, D. Liu, Z.J. Zhang, et al., Structure-based discovery of an organic compound that binds Bcl-2 protein and induces apoptosis of tumor cells, Proc. Natl. Acad. Sci. U.S.A. 97(2000) 7124-7129.
[11] J.F. Cheng, A. Ishikawa, Y. Ono, T. Arrheniusa, A. Nadzana, Novel chromene derivatives as TNF-α inhibitors, Bioorg. Med. Chem. Lett. 13(2003) 3647-3650.
[12] D. Grée, S. Vorin, L. Manthati, et al., The synthesis of new, selected analogues of the pro-apoptotic and anticancer molecule HA 14-1, Tetrahedron Lett. 49(2008) 3276-3278.
[13] W. Kemnitzer, S. Jiang, H. Zhang, et al., Discovery of 4-aryl-2-oxo-2H-chromenes as a new series of apoptosis inducers using a cell-and caspase-based highthroughput screening assay, Bioorg. Med. Chem. Lett. 18(2008) 5571-5575.
[14] M.M. Khafagy, A.H.F.A. El-Wahas, F.A. Eid, A.M. El-Agrody, Synthesis of halogen derivatives of benzo[h]chromene and benzo[a]anthracene with promising antimicrobial activities, Farmaco 57(2002) 715-722.
[15] M. Kidwai, S. Saxena, M.K. Rahman Khan, S.S. Thukral, Aqua mediated synthesis of substituted 2-amino-4H-chromenes and in vitro study as antibacterial agents, Bioorg. Med. Chem. Lett. 15(2005) 4295-4298.
[16] B.S. Kumar, N. Srinivasulu, R.H. Udupi, et al., Efficient synthesis of benzo[g]-and benzo[h]chromene derivatives by one-pot three-component condensation of aromatic aldehydes with active methylene compounds and naphthols, Russ. J. Org. Chem. 42(2006) 1813-1815.
[17] R.R. Kumar, S. Perumal, P. Senthilkumar, P. Yogeeswari, D. Sriramm, An atom efficient, solvent-free, green synthesis and antimycobacterial evaluation of 2-amino-6-methyl-4-aryl-8-[(E)-arylmethylidene]-5,6,7,8-tetrahydro-4H-pyrano[3,2-c]pyridine-3-carbonitriles, Bioorg. Med. Chem. Lett. 17(2007) 6459-6462.
[18] V.K. Tandon, M. Vaish, S. Jain, D.S. Bhakuni, R.C. Srimal, Synthesis, carbon-13 NMR and hypotensive action of 2,3-dihydro-2,2-dimethyl-4H-naphtho[1,2-b]pyran-4-one, Indian J. Pharm. Sci. 53(1991) 22-23.
[19] M. Longobardi, A. Bargagna, E. Mariani, P. Schenone, E. Marmo, 2H-[1] benzothiepino[5,4-b]pyran derivatives with local anesthetic and antiarrhythmic activities, Farmaco 45(1990) 399-413.
[20] H. Bedair, A. El-Hady, S. Abd El-Latif, H. Fakery, M. El-Agrody, 4-Hydroxycoumarin in heterocyclic synthesis part ⅡI. Synthesis of some new pyrano[2,3-d]pyrimidine, 2-substituted[1,2,4] triazolo[1,5-c]pyrimidine and pyrimido[1,6-b][1,2,4] triazine derivatives, Farmaco 55(2000) 708-714.
[21] M.M. Heravi, K. Bakhtiari, V. Zadsirjan, F. Bamoharram, Aqua mediated synthesis of substituted 2-amino-4H-chromenes catalyzed by green and reusable Preyssler heteropolyacid, Bioorg. Med. Chem. Lett. 17(2007) 4262-4265.
[22] C. Bruhlmann, F. Ooms, P. Carrupt, et al., Coumarins derivatives as dual inhibitors of acetylcholinesterase and monoamine oxidase, J. Med. Chem. 44(2001) 3195-3198.
[23] S.R. Kesten, T.G. Heffner, S.J. Johnson, et al., Design, synthesis, and evaluation of chromen-2-ones as potent and selective human dopamine D4 antagonists, J. Med. Chem. 42(1999) 3718-3725.
[24] V.P. Reddy, A.V. Kumar, K. Swapna, K.R. Rao, Copper oxide nanoparticle-catalyzed coupling of diaryl diselenide with aryl halides under ligand-free conditions, Org. Lett. 11(2009) 951-953.
[25] N.Mittapelly,B.R.Reguri,K.Mukkanti,Copperoxidenanoparticles-catalyzeddirect N-alkylation of amines with alcohols, Der Pharma Chemica 3(2011) 180-189.
[26] S. Abdolmohammadi, M. Afsharpour, Facile one-pot synthesis of pyrido[2,3-d]pyrimidine derivatives over ZrO2 nanoparticles catalyst, Chin. Chem. Lett. 23(2012) 257-260.
[27] S. Abdolmohammadi, S. Balalaie, A clean procedure for synthesis of pyrido[d]pyrimidine derivatives under solvent-free conditions catalyzed by ZrO2 nanoparticles, Comb. Chem. High Throughput Screen. 15(2012) 395-399.
[28] S. Abdolmohammadi, M. Mohammadnejad, F. Shafaei, TiO2 nanoparticles as an efficient catalyst for the one-pot preparation of tetrahydrobenzo[c]acridines in aqueous media, Z. Naturforsch. B 68b(2013) 362-366.
[29] S. Abdolmohammadi, S. Balalaie, M. Barari, F. Rominger, Three-component green reaction of arylaldehydes 6-amino-1,3-dimethyluracil and active methylene compounds catalyzed by Zr(HSO4)4 under solvent-free conditions, Comb. Chem. High Throughput Screen. 16(2013) 150-159.
[30] M. Tajbakhsh, E. Alaee, H. Alinezhad, et al., Titanium dioxide nanoparticles catalyzed synthesis of Hantzsch esters and polyhydroquinoline derivatives, Chin. J. Catal. 33(2012) 1517-1522.
[31] D. Ma, C. Xia, CuI-catalyzed coupling reaction of β-amino acids or esters with aryl halides at temperature lower than that employed in the normal Ullmann reaction. Facile synthesis of SB-214857, Org. Lett. 3(2001) 2583-2586.
[32] H. Zhang, Q. Cai, D. Ma, Amino acid promoted CuI-catalyzed C-N bond formation between aryl halides and amines or N-containing heterocycles, J. Org. Chem. 70(2005) 5164-5173.
[33] V.D. Bock, H. Hiemstra, J.H. van Maarseveen, CuI-catalyzed alkyne-azide "click" cycloadditions from a mechanistic and synthetic perspective, Eur. J. Org. Chem. 1(2006) 51-68.
[34] J. Safaei-Ghomi, A. Ziarati, R. Teymuri, CuI nanoparticles as new, efficient and reusable catalyst for the one-pot synthesis of 1,4-dihydropyridines, Bull. Korean Chem. Soc. 33(2012) 2679-2682.
[35] H.R. Kalita, A.J. Borah, P. Phukan, Mukaiyama aldol reaction of trimethylsilyl enolate with aldehyde catalyzed by CuI, Indian J. Chem. 52B(2013) 289-292.
[36] Y.F. Liu, J.H. Zhan, J.H. Zeng, et al., Ethanolthermal synthesis to gamma-Cul nanocrystals at low temperature, J. Mater. Sci. Lett. 20(2001) 1865-1867.
[37] M. Ferhat, A. Zaoui, M. Certier, J.P. Dufour, B. Khelifa, Electronic structure of the copper halides CuCl, CuBr and Cul, Mater. Sci. Eng. B 39(1996) 95-100.
[38] H. Feraoun, H. Aourag, M. Certier, Theoretical studies of substoichiometric CuI, Mater. Chem. Phys. 82(2003) 597-601.
[39] M. Kidwai, S. Rastogi, Reaction of coumarin derivatives with nucleophiles in aqueous medium, Z. Naturforsch. B 63(b)(2008) 71-76.
[40] K.S. Niralwad, B.B. Shingate, M.S. Shingare, Ultrasound-assisted one-pot synthesis of octahydroquinazolinone derivatives catalyzed by acidic ionic liquid[tbmim]Cl2/AlCl3, J. Chin. Chem. Soc. 57(2010) 89-92.
[41] P.V. Badadhe, A.V. Chate, D.G. Hingane, et al., Microwave-assisted one-pot synthesis of octahydroquinazolinone derivatives catalyzed by thiamine hydrochloride under solvent-free condition, J. Korean Chem. Soc. 55(2011) 936-939.
[42] S. Karami, B. Karami, S. Khodabakhshi, Solvent-free synthesis of novel and known octahydroquinazolinones/thiones by the use of ZrOCl2·8H2O as a highly efficient and reusable catalyst, J. Chin. Chem. Soc. 60(2013) 22-26.
[43] A.M.A. Al-Kadasi, G.M. Nazeruddin, A facile and efficient ultrasound-assisted chlorosulfonic acid catalyzed one-pot synthesis of benzopyranopyrimidines under solvent-free conditions, J. Chem. Pharm. Res. 5(2013) 204-210.
[44] F. Tavakoli, M. Salavati-Niasari, D. Ghanbari, K. Saberyan, S.M. HosseinpourMashkani, Application of glucose as a green capping agent and reductant to fabricate CuI micro/nanostructures, Mater. Res. Bull. 49(2014) 14-20.