CuO hollow nanosphere-catalyzed cross-coupling of aryl iodides with thiols
© Woo et al.; licensee Springer. 2013
Received: 17 July 2013
Accepted: 12 September 2013
Published: 17 September 2013
New functionalized CuO hollow nanospheres on acetylene black (CuO/AB) and on charcoal (CuO/C) have been found to be effective catalysts for C-S bond formation under microwave irradiation. CuO catalysts showed high catalytic activity with a wide variety of substituents which include electron-rich and electron-poor aryl iodides with thiophenols by the addition of two equivalents of K2CO3 as base in the absence of ligands.
KeywordsMicrowave Copper oxide Acetylene black Heterogeneous Ullmann
Sulfur-containing aromatic compounds, notably aryl sulfides and their derivatives, are prominent in fields such as biological, pharmaceutical, and materials fields. In particular, their use in synthesizing biologically and pharmaceutically important organosulfur compounds such as HIV protease inhibitors  (Viracept, Nelfinavir Mesylate, AG 1343), LFA-1/ICAM-1 antagonists , and arylthioindoles  (potent inhibitors of tubulin assembly) is still not fully understood by synthetic chemists. In general, molecules containing one or more carbon-sulfur bonds can be used as molecular precursors for the synthesis of new materials . However, compared to C-N and C-O bonds, the transition metal-catalyzed C(aryl)-S bond formation has not been well studied. This bond formation is thought to be partial because of the formation of an S-S coupled product and a concurrent deactivation of the metal catalyst due to the strong coordinative and adsorptive properties of sulfur, which can decrease catalytic activity . General methods for C-S cross-coupling involve the condensation of aryl halides with thiols and, usually, require temperatures greater than 200°C. These methods also require strongly basic, toxic, high-boiling, polar solvents, namely HMPA, quinolone, or N,N-dimethylacetamide. In order to circumvent these complications, a meticulous effort has been focused on the development of transition metal-catalyzed coupling of thiophenols with aryl halides. Previously, iron , nickel [7, 8], palladium [9, 10], cobalt , and copper-based [12–16] catalytic systems have been reported for this purpose. Even though significant improvements have been made, appropriate techniques are still needed for the synthesis of diaryl thioethers. To date, metal and metal oxide nanoparticles have often been used as metal catalysts because of their physical and chemical stability. In addition, the advantage of nanoparticles including large surface area and heterogeneous nature make them applicable to a broad range of scientific fields and functions such as the immobilization of biomolecules , catalysis of organic [18–23] and electrochemical reactions , use in electrochemical sensors and biosensors , enhancement of electron transfer , labeling of biomolecules , and synthesis of nanofluids , antibacterial materials , photocatalysts [25, 26], solar cells , and so on. Among the various available metal oxide nanoparticles, two copper oxides (Cu2O, CuO) have been studied for use in p-type semiconductor materials with narrow band gaps. This is because copper oxides are less expensive, recyclable, and non-toxic and have suitable optical and electronic properties [28–32]. Thus, as part of the effort to find new catalytic systems and better understand the role of transition metal nanoparticles in organic transformations, we report herein the use of CuO hollow nanoparticles as catalysts for efficient syntheses of diaryl thioethers. These CuO hollow nanoparticles have advantages in terms of large-scale synthesis and uniform shape compared to previous reported CuO nanoparticles [33, 34]. In recent times, microwave-irradiated organic reactions have become increasingly popular as valuable alternatives to the use of conductive heating for promoting chemical reactions. Besides, improved yields within short reaction time were observed. Microwave activation, as a non-conventional energy source, is becoming a very popular and valuable technique in organic synthesis, as evidenced by the increasing number of annual publications on this topic. In continuation of our previous reports , we discovered that microwave irradiation can even accelerate the Ullmann coupling of activated aryl iodides and thiophenols.
Reagents were purchased from Aldrich Chemical Co. (St. Louis, MO, USA) and Strem Chemical Co. (Bischheim, France) and used as received. Reaction products were analyzed by the literature values of known compounds. CuO, CuO/AB, and CuO/C were characterized by transmission electron microscopy (TEM) (Philips F20 Tecnai operated at 200 kV, KAIST, Amsterdam, the Netherlands). Samples were prepared by placing a few drops of the corresponding colloidal solution on carbon-coated copper grids (Ted Pellar, Inc., Redding, CA, USA). The X-ray diffractometer (XRD) patterns were recorded on a Rigaku D/MAX-RB (12 kW; Shibuya-ku, Japan) diffractometer. The copper loading amounts were measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Elemental compositions of CuO/AB were obtained using energy-dispersive X-ray spectroscopy (EDS) (550i, IXRF Systems, Inc., Austin, TX, USA).
Preparation of Cu2O nanocubes
Poly(vinylpyrrolidone) (PVP, Aldrich, Mw 55,000; 5.3 g), dissolved in 45 mL of 1,5-pentanediol (PD, Aldrich, 96%), was heated to 240°C under inert conditions. Then, 4.0 mmol of Cu(acac)2 (Strem, 98%), dissolved in 15 mL of PD, was injected into the hot PVP solution at 240°C, and the mixture was stirred for 15 min at the same temperature. The resulting colloidal dispersion was cooled to room temperature, and the product was separated by adding 150 mL of acetone, with centrifugation at 8,000 rpm for 20 min. The precipitates were washed with ethanol several times and re-dispersed in 50 mL of ethanol.
Synthesis of CuO hollow nanostructures
An appropriate concentration of aqueous ammonia solution was added to 25 mL of the Cu2O cube dispersion in ethanol (16 mM with respect to the precursor concentration). The mixture was subjected to stirring at room temperature for 2 h. The volume and concentration of the aqueous ammonia solution used for each structure were 1.0 mL and 14.7 M, respectively, for hollow cubes; 2.0 mL and 7.36 M, respectively, for hollow spheres; and 6.0 mL and 2.45 M for urchin-like particles, respectively. For shape optimization of the hollow spheres, a 3.68-M aqueous ammonia solution was used. After the reaction, the products were collected by centrifugation at 6,000 rpm for 20 min.
Synthesis procedures of CuO/AB and CuO/C
The acetylene carbon black (STREM, 99.99%, 1.2 g) was mixed with 100 mL of the CuO hollow nanosphere dispersion in ethanol (17.0 mM), and the reaction mixture was sonicated for 1 h at room temperature. After 1 h, the product CuO/AB was washed with ethanol several times and vacuum dried at room temperature. For the synthesis of CuO/C, the mixture solution of charcoal (0.8 g) and 50.0 mL of CuO hollow nanosphere dispersion in ethanol (50.0 mM) was refluxed for 4 h. After 4 h, the black suspension was cooled to room temperature and precipitated by centrifugation. The product CuO/C was washed with ethanol thoroughly and dried in a vacuum oven at room temperature.
General procedure for cross-coupling of aryl halides with thiophenol
Into a 10-mL glass vial, 4.0 mg of CuO/AB and CuO/C, iodobenzene (0.11 mL, 1.0 mmol), thiophenol (0.11 mL, 1.1 mmol), and solvent (5.0 ml) were placed. The reaction mixture was irradiated with a microwave stove (MAS II, Sineo Microwave Chemistry Technology Co., Ltd., Shanghai, China) for 10 to 30 min. After reaction, the vial was cooled to RT. The solution was then filtered, concentrated under reduced pressure, and characterized by Gas chromatography–mass spectrometry (GC-MS) spectra. Yields were based on the amount of iodobenzene used in each reaction.
Results and discussion
Ullmann reaction of aryl halides with thiols catalyzed by CuO hollow nanoparticles
In conclusion, CuO hollow nanospheres were synthesized by controlled oxidation of Cu2O nanocubes using aqueous ammonia solutions. Ullmann coupling reactions of aryl iodide with thiols were conducted to check the respective catalytic activities of CuO, CuO/AB, and CuO/C hollow nanosphere catalysts under microwave irradiation. Various diaryl thioethers were obtained from electron-deficient aryl iodides, while diaryl disulfide was produced from electron-rich aryl iodides. Transition metals loaded on acetylene black or charcoal have significant importance in the field of organic synthesis. Furthermore, it is noteworthy that these heterogeneous systems are characterized by high chemical atomic efficiency, which is advantageous in industrial catalysts.
CuO hollow nanospheres on acetylene black
CuO hollow nanospheres on charcoal
Energy-dispersive X-ray spectroscopy
Inductively coupled plasma atomic emission spectroscopy
Transmission electron microscopy
This work was supported by a 2-year Research Grant of Pusan National University and National Research Foundation of Korea (NRF) through the Human Resource Training Project for Regional Innovation.
- Kaldor SW, Kalish VJ, Davies JFII, Shetty BV, Fritz JE, Appelt K, Burgess JA, Campanale M, Chirgadze NY, Clawson DK, Dressman BA, Hatch SD, Khalil DA, Kosa MB, Lubbehusen PP, Muesing MA, Patick AK, Reich SH, Su KS, Tatlock JH: Viracept (nelfinavir mesylate, AG1343): a potent, orally bioavailable inhibitor of HIV-1 protease. J Med Chem 1997, 40: 3979–3985. 10.1021/jm9704098View ArticleGoogle Scholar
- Liu G, Huth JR, Olejniczak ET, Mendoza R, DeVries P, Leitza S, Reilly EB, Okasinski GF, Fesik SW, von Geldern TW: Novel p-arylthio cinnamides as antagonists of leukocyte function-associated antigen-1/intracellular adhesion molecule-1 interaction. 2. mechanism of inhibition and structure-based improvement of pharmaceutical properties. J Med Chem 2001, 44: 1202–1210. 10.1021/jm000503fView ArticleGoogle Scholar
- Martino GD, Edler MC, Regina GL, Coluccia A, Barbera MC, Barrow D, Nicholson RI, Chiosis G, Brancale A, Hamel E, Artico M, Silvestri R: New arylthioindoles: potent nhibitors of tubulin polymerization. 2. structure − activity relationships and molecular modeling studies. J Med Chem 2006, 49: 947–954. 10.1021/jm050809sView ArticleGoogle Scholar
- Wang Y, Chackalamannil S, Hu Z, Clader JW, Greenlee W, Billard W, Binch H, Crosby G, Ruperto V, Duffy RA, McQuade R, Lachowicz JE: Design and synthesis of piperidinyl piperidine analogues as potent and selective M2 muscarinic receptor antagonists. Bioorg Med Chem Lett 2000, 10: 2247–2250. 10.1016/S0960-894X(00)00457-1View ArticleGoogle Scholar
- Kondo T, Mitsudo TA: Metal-catalyzed carbon-sulfur bond formation. Chem Rev 2000, 100: 3205–3220. 10.1021/cr9902749View ArticleGoogle Scholar
- Correa A, Carril M, Bolm C: Iron-catalyzed S-arylation of thiols with aryl iodides. Angew Chem Int Ed 2008, 47: 2880–2883. 10.1002/anie.200705668View ArticleGoogle Scholar
- Zhang Y, Ngeow KN, Ying JY: The first N-heterocyclic carbene-based nickel catalyst for C-S coupling. Org Lett 2007, 9: 3495–3499. 10.1021/ol071248xView ArticleGoogle Scholar
- Jammi S, Barua P, Rout L, Saha P, Punniyamurthy T: Efficient ligand-free nickel-catalyzed C–S cross-coupling of thiols with aryl iodides. Tetrahedron Lett 2008, 49: 1484–1487. 10.1016/j.tetlet.2007.12.118View ArticleGoogle Scholar
- Fernandez-Rodriguez MA, Shen Q, Hartwig JF: Highly efficient and functional-group-tolerant catalysts for the falladium-catalyzed coupling of aryl chlorides with thiols. Chem Eur J 2006, 12: 7782–7796. 10.1002/chem.200600949View ArticleGoogle Scholar
- Fernandez-Rodriguez MA, Shen Q, Hartwig JF: A general and long-lived catalyst for the palladium-catalyzed coupling of aryl halides with thiols. J Am Chem Soc 2006, 128: 2180–2181. 10.1021/ja0580340View ArticleGoogle Scholar
- Wong YC, Jayanth TT, Cheng CH: Cobalt-catalyzed aryl-sulfur bond formation. Org Lett 2006, 8: 5613–5616. 10.1021/ol062344lView ArticleGoogle Scholar
- Lv X, Bao WA: β-keto ester as a novel, efficient, and versatile ligand for copper(I)-catalyzed C-N, C-O, and C-S coupling reactions. J Org Chem 2007, 72: 3863–3867. 10.1021/jo070443mView ArticleGoogle Scholar
- Carril M, SanMartin R, Dominguez E, Tellitu I: Simple and efficient recyclable catalytic system for performing copper-catalysed S-arylation reactions in the presence of water. Chem Eur J 2007, 13: 5100–5105. 10.1002/chem.200601737View ArticleGoogle Scholar
- Verma AK, Singh J, Chaudhary R: A general and efficient CuI/BtH catalyzed coupling of aryl halides with thiols. Tetrahedron Lett 2007, 48: 7199–7202. 10.1016/j.tetlet.2007.07.205View ArticleGoogle Scholar
- Rout L, Saha P, Jammi S, Punniyamurthy T: Efficient copper(I)-catalyzed C–S cross coupling of thiols with aryl halides in water. Eur J Org Chem 2008, 4: 640–643.View ArticleGoogle Scholar
- Sperotto E, van Klink GPM, de Vries JG, van Koten G: Ligand-free copper-catalyzed C-S coupling of aryl iodides and thiols. J Org Chem 2008, 73: 5625–5628. 10.1021/jo800491kView ArticleGoogle Scholar
- Luo X, Morrin A, Killard AJ, Smyth MR: Application of nanoparticles in electrochemical sensors and biosensors. Electroanalysis 2006, 18: 319–326. 10.1002/elan.200503415View ArticleGoogle Scholar
- Harsha Vardhan Reddy K, Prakash Reddy V, Shankar J, Madhav B, Anil Kumar BSP, Nageswar YVD: Copper oxide nanoparticles catalyzed synthesis of aryl sulfides via cascade reaction of aryl halides with thiourea. Tetrahedron Lett 2011, 52: 2679–2682. 10.1016/j.tetlet.2011.03.070View ArticleGoogle Scholar
- Satish G, Harsha Vardhan Reddy K, Ramesh K, Karnakar K, Nageswar YVD: Synthesis of 2-N-substituted benzothiazoles via domino condensation-hetero cyclization process, mediated by copper oxide nanoparticles under ligand-free conditions. Tetrahedron Lett 2012, 53: 2518–2521. 10.1016/j.tetlet.2012.03.012View ArticleGoogle Scholar
- Prakash Reddy V, Vijay Kumar A, Rama Rao K: Copper oxide nanoparticles catalyzed vinylation of imidazoles with vinyl halides under ligand-free conditions. Tetrahedron Lett 2010, 51: 3181–3185. 10.1016/j.tetlet.2010.04.022View ArticleGoogle Scholar
- Lin K-S, Pan C-Y, Chowdhury S, Tu M-T, Hong W-T, Yeh C-T: Hydrogen generation using a CuO/ZnO-ZrO2 nanocatalyst for autothermal reforming of methanol in a microchannel reactor. Molecules 2011, 16: 348–366. 10.3390/molecules16010348View ArticleGoogle Scholar
- Monopoli A, Nacci A, Calò V, Ciminale F, Cotugno P, Mangone A, Giannossa LC, Azzone P, Cioffi N: Palladium/zirconium oxide nanocomposite as a highly recyclable catalyst for c-c coupling reactions in water. Molecules 2010, 15: 4511–4525. 10.3390/molecules15074511View ArticleGoogle Scholar
- Woo H, Kang H, Kim A, Jang S, Park JC, Park S, Kim B-S, Song H, Park KH: Azide-alkyne huisgen [3 + 2] cycloaddition using CuO nanoparticles. Molecules 2012, 17: 13235–13252. 10.3390/molecules171113235View ArticleGoogle Scholar
- Chang M-H, Liu H-S, Tai CY: Preparation of copper oxide nanoparticles and its application in nanofluid. Powder Technol 2011, 207: 378–386. 10.1016/j.powtec.2010.11.022View ArticleGoogle Scholar
- Akhavan O, Ghaderi E: Cu and CuO nanoparticles immobilized by silica thin films as antibacterial materials and photocatalysts. Surf Coat Technol 2010, 205: 219–223. 10.1016/j.surfcoat.2010.06.036View ArticleGoogle Scholar
- Meng Z-D, Zhu L, Ye S, Sun Q, Ullah K, Cho K-Y, Oh W-C: Fullerene modification CdSe/TiO2 and modification of photocatalytic activity under visible light. Nanoscale Res Lett 2013, 8: 189–199. 10.1186/1556-276X-8-189View ArticleGoogle Scholar
- Yeo CI, Kim JB, Song YM, Lee YT: Antireflective silicon nanostructures with hydrophobicity by metal-assisted chemical etching for solar cell applications. Nanoscale Res Lett 2013, 8: 159–166. 10.1186/1556-276X-8-159View ArticleGoogle Scholar
- Ma D, Cai Q: N, N-dimethyl glycine-promoted Ullmann coupling reaction of phenols and aryl halides. Org Lett 2003, 5: 3799–3802. 10.1021/ol0350947View ArticleGoogle Scholar
- Altman RA, Shafir A, Choi A, Lichtor PA, Buchwald SL: An improved Cu-based catalyst system for the reactions of alcohols with aryl halides. J Org Chem 2008, 73: 284–286. 10.1021/jo702024pView ArticleGoogle Scholar
- Huang F, Quach TD, Batey RA: Copper-catalyzed nondecarboxylative cross coupling of alkenyltrifluoroborate salts with carboxylic acids or carboxylates: synthesis of enol esters. Org Lett 2013, 15: 3150–3153. 10.1021/ol4013712View ArticleGoogle Scholar
- Zhang Y, Yang X, Yao Q, Ma D: CuI/DMPAO-catalyzed N-arylation of acyclic secondary amines. Org Lett 2012, 14: 3056–3059. 10.1021/ol301135cView ArticleGoogle Scholar
- Kumar RV, Elgamiel R, Diamant Y, Gedanken A, Norwig J: Sonochemical preparation and characterization of nanocrystalline copper oxide embedded in poly(vinyl alcohol) and its effect on crystal growth of copper oxide. Langmuir 2001, 17: 1406–1410. 10.1021/la001331sView ArticleGoogle Scholar
- Gou L, Murphy CJ: Solution-phase synthesis of Cu2O nanocubes. Nano Lett 2003, 3: 231–234. 10.1021/nl0258776View ArticleGoogle Scholar
- Chang Y, Teo JJ, Zeng HC: Formation of colloidal CuO nanocrystallites and their spherical aggregation and reductive transformation to hollow Cu2O nanospheres. Langmuir 2005, 21: 1074–1079. 10.1021/la047671lView ArticleGoogle Scholar
- Kang H, Lee HJ, Park JC, Song H, Park KH: Solvent-free microwave promoted [3 + 2] cycloaddition of alkyne-azide in uniform CuO hollow nanospheres. Top Catal 2010, 53: 523–528. 10.1007/s11244-010-9481-0View ArticleGoogle Scholar
- Park JC, Kim J, Kwon H, Song H: Gram-scale synthesis of Cu2O nanocubes and subsequent oxidation to CuO hollow nanostructures for lithium-ion battery anode materials. Adv Mater 2009, 21: 803–807. 10.1002/adma.200800596View ArticleGoogle Scholar
- Wu CK, Yin M, O’Brien S, Koberstein JT: Quantitative analysis of copper oxide nanoparticle composition and structure by X-ray photoelectron spectroscopy. Chem Mater 2006, 18: 6054–6058. 10.1021/cm061596dView ArticleGoogle Scholar
- Sperotto E, van Klink GPM, van Koten G, de Vries JG: The mechanism of the modified Ullmann reaction. Dalton Trans 2010, 39: 10338–10351. 10.1039/c0dt00674bView ArticleGoogle Scholar
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