Propargylic substitution reactions with various nucleophilic compounds using efficient and recyclable mesoporous silica spheres embedded with FeCo/graphitic shell nanocrystals
Tóm tắt
Phosphomolybdic acid (PMA, H3PMo12O40) functioned as a catalyst for reactions of secondary propargylic alcohols and nucleophiles. Highly stable and magnetically recyclable mesoporous silica spheres (MMS) embedded with FeCo-graphitic carbon shell nanocrystals (FeCo/GC@MSS) were fabricated by a modified Stöber process and chemical vapor deposition (CVD) method. The FeCo/GC@MSS were loaded with phosphomolybdic acid (PMA@FeCo/GC@MSS), and their catalytic activity was investigated. Propargylic reactions of 1,3-diphenyl-2-propyn-1-ol with a wide range of nucleophiles bearing activating substituents were catalyzed under mild conditions. It was found that the MMS possess mesoporosities and have enough inner space to load FeCo and phosphomolybdic acid. The FeCo/GC@MSS were found to be chemically stable against acid etching and oxidation. This suggests that the nanocrystals can be used as a support for an acid catalyst. Moreover, the magnetic property of the nanocrystals enabled the facile separation of catalysts from the products.
Tài liệu tham khảo
Olah GA, Torok B, Joschek JP, Bucsi I, Esteves PM, Rasul G, Surya Prakash GK: Efficient chemoselective carboxylation of aromatics to arylcarboxylic acids with a superelectrophilically activated carbon dioxide-Al 2 Cl 6 /Al system.J Am Chem Soc 2002, 124:11379–91. 10.1021/ja020787o
Schnatter WF, Rogers DW, Zavitsas AA: Electrophilic aromatic substitution: enthalpies of hydrogenation of the ring determine reactivities of C 6 H 5 X. The direction of the C 6 H 5 -X bond dipole determines orientation of the substitution.J Phys Chem A 2013, 117:13079–88. 10.1021/jp409623j
Jayaraman A, Sterenberg BT: Electrophilic aromatic substitution reactions of a tungsten-coordinated phosphirenyl triflate.Organometallics 2014, 33:522–30. 10.1021/om401050w
Yadav JS, Reddy BVS, Rao KVR, Narender R: InBr 3 -catalyzed annulations of cyclic 1,3-diketones with aryl propargyl alcohols: a novel synthesis of 2,4-diaryldihydropyrans.Tetrahedron Lett 2009, 50:3963–5. 10.1016/j.tetlet.2009.04.088
Srihari P, Bhunia DC, Sreedhar P, Mandal SS, Reddy JSS, Yadav JS: Iodine-catalyzed C- and O-nucleophilic substitution reactions of aryl-propargyl methanols.Tetrahedron Lett 2007, 48:8120–4. 10.1016/j.tetlet.2007.09.123
Misono M, Ono I, Koyano G, Aoshima A: Heteropolyacids. Versatile green catalysts usable in a variety of reaction media.Pure Appl Chem 2000, 72:1305–11.
Reddy BVS, Narasimhulu G, Lakshumma PS, Reddy YV, Yadav JS: Phosphomolybdic acid: a highly efficient solid acid catalyst for the synthesis of trans-4,5-disubstituted cyclopentenones.Tetrahedron Lett 2012, 53:1776–9. 10.1016/j.tetlet.2012.01.115
Azizi N, Torkiyan L, Saidi MR: Highly efficient one-pot three-component Mannich reaction in water catalyzed by heteropoly acids.Org Lett 2006, 8:2079–82. 10.1021/ol060498v
Kumar GD, Baskaran S: Heteropoly acid as a novel nitrene transfer agent: a facile and practical aziridination of olefins with Chloramine-T.Chem Commun 2004, 8:1026–7.
Hamamoto H, Anilkumar G, Tohma H, Kita Y: A novel and useful oxidative intramolecular coupling reaction of phenol ether derivatives on treatment with a combination of hypervalent iodine(III) reagent and heteropoly acid.Chem Eur J 2002, 8:5377–83. 10.1002/1521-3765(20021202)8:23<5377::AID-CHEM5377>3.0.CO;2-H
Rafiee E, Jafari H: A practical and green approach towards synthesis of dihydropyrimidinones: using heteropoly acids as efficient catalysts.Bioorg Med Chem Lett 2006, 16:2463–6. 10.1016/j.bmcl.2006.01.087
Seo MH, Choi SM, Kim HJ, Kim JH, Cho BK, Kim WB: A polyoxometalate-deposited Pt/CNT electrocatalyst via chemical synthesis for methanol electrooxidation.J Power Sources 2008, 179:81–6. 10.1016/j.jpowsour.2007.12.107
Cui Z, Li CM, Jiang SP: PtRu catalysts supported on heteropolyacid and chitosan functionalized carbon nanotubes for methanol oxidation reaction of fuel cells.Phys Chem Chem Phys 2011, 13:16349–57. 10.1039/c1cp21271k
Srihari P, Reddy JSS, Mandal SS, Satyanarayana K, Yadav JS: PMA-silica gel catalyzed propargylation of aromatic compounds with arylpropargyl alcohols under solvent-free conditions.Synthesis-Stuttgart 2008, 12:1853–60.
Mallik S, Dash SS, Parida KM, Mohapatra BK: Synthesis, characterization, and catalytic activity of phosphomolybdic acid supported on hydrous zirconia.J Colloid Interf Sci 2006, 300:237–43. 10.1016/j.jcis.2006.03.047
Li Y, Kim YJ, Kim AY, Lee K, Jung MH, Hur NH, Park KH, Seo WS: Highly stable and magnetically recyclable mesoporous silica spheres embedded with FeCo/graphitic shell nanocrystals for supported catalysts.Chem Mater 2011, 23:5398–403. 10.1021/cm202451n
Cullity BD: Elements of X-ray Diffraction. 2nd edition. MA: Addison-Wesley Publishing Company; 1978.
Brunauer S, Deming LS, Deming WE, Teller E: A theory of the van der Waals adsorption of gases.J Am Chem Soc 1940, 62:1723–32. 10.1021/ja01864a025
Wang T, Ma R-d, Liu L, Zhan Z-p: Solvent-free solid acid-catalyzed nucleophilic substitution of propargylic alcohols: a green approach for the synthesis of 1,4-diynes.Green Chem 2010, 12:1576–9. 10.1039/c0gc00117a
Masuyama Y, Hayashi M, Suzuki N: SnCl 2 -catalyzed propargylic substitution of propargylic alcohols with carbon and nitrogen nucleophiles.Eur J Org Chem 2013, 2013:2914–21. 10.1002/ejoc.201201673