2979-28-4Relevant academic research and scientific papers
Cross-linked poly(N-vinylpyrrolidone)-titanium tetrachloride complex: A novel stable solid TiCl4 equivalent as a recyclable polymeric Lewis acid catalyst for regioselective ring-opening alcoholysis of epoxides
Rahmatpour, Ali,Sajjadinezhad, Seyed Mehrzad
, (2021/08/09)
Cross-linked poly(N-vinylpyrrolidone) resin beads were prepared as macromolecular ligand precursors by suspension copolymerization of N-vinyl-2-pyrrolidone and N,N′-methylenebisacrylamide (MBA) as a crosslinking agent in water. Subsequently, the resulting polymer carrier precursor was readily combined with titanium tetrachloride to form a stable polymeric coordination complex (PNVP/TiCl4), and this novel stable TiCl4 equivalent evaluated as a heterogeneous and reusable solid Lewis acid catalyst for the regio-and stereoselective nucleophilic ring opening of various epoxides with various alcohols to prepare β-alkoxy alcohols in excellent yields without generating any waste. The MBA-cross-linked PNVP and resultant catalyst were characterized by Fourier transform infrared spectroscopy (FT–IR), field-emission scanning electron microscope (FE–SEM), energy dispersive X-ray (EDX), inductively coupled plasma (ICP), and thermogravimetric analysis (TGA) techniques. Moreover, the catalyst is very stable, easily separated, and reused at least five times without significant loss of activity. In terms of scope, yields, the amount of catalyst used, and reaction time, the PNVP-TiCl4 complex catalyst is an improvement over previously reported heterogeneous catalysts for ring opening of epoxides methods. Further, the experimental outcome revealed that using the copolymer beads as carriers with a high percentage of crosslinking and the high mesh size leads had an adverse effect on the reaction rate.
MBA-cross-linked poly(N-vinyl-2-pyrrolidone)/ferric chloride macromolecular coordination complex as a novel and recyclable Lewis acid catalyst: Synthesis, characterization, and performance toward for regioselective ring-opening alcoholysis of epoxides
Rahmatpour, Ali,Zamani, Maryam
, (2021/09/30)
A novel macromolecular-metal coordination complex, MBA-cross-linked PNVP/FeCl3 material was fabricated by immobilization of water intolerant ferric chloride onto the porous cross-linked poly(N-vinyl-2-pyrrolidone) carrier beads as a macromolecular ligand or carrier which was prepared by suspension free-radical copolymerization of N-vinyl-2-pyrrolidone (NVP) and N,N′-methylene bis-acrylamide (MBA) as a crosslinking agent in water. The obtained PNVP/FeCl3 was characterized by UV/vis and FT-IR spectroscopies, TGA, FE-SEM, EDX, and ICP techniques. This heterogenized version of ferric chloride is a convenient and safe alternative to highly water intolerant ferric chloride. The catalytic performance of (PNVP/FeCl3) as an efficient and recyclable polymeric Lewis acid catalyst was appropriately probed in the regio-and stereoselective nucleophilic ring opening of various epoxides with various alcohols in excellent yields with TOF up to 182.48 h?1 without generating any waste. The activity data indicate that this heterogeneous catalyst is very active and could be easily recovered, and reused at least six times without appreciable loss of activity indicating its stability under experimental conditions.
A highly efficient protocol for regioselective ring-opening of epoxides with alcohols, water, acetic acid, and acetic anhydride catalyzed by SbF3
Zeynizadeh, Behzad,Gilanizadeh, Masumeh,Aminzadeh, Farkhondeh Mohammad
, p. 1051 - 1056 (2016/07/06)
SbF3as an efficient catalyst has been used for regioselective alcoholysis, acetolysis and hydrolysis of epoxides to the corresponding β-alkoxy, β-acetoxy alcohols, and 1,2-diols in high to excellent yields. This study also represents a convenient synthesis of vic-diacetates from ring-opening of epoxides with acetic anhydride.
Enhanced metal loading in SBA-15-type catalysts facilitated by salt addition: Synthesis, characterization and catalytic epoxide alcoholysis activity of molybdenum incorporated porous silica
Budhi, Sridhar,Peeraphatdit, Chorthip,Pylypenko, Svitlana,Nguyen, Vy H.T.,Smith, Emily A.,Trewyn, Brian G.
, p. 469 - 476 (2014/03/21)
We report a novel method to increase the metal loading in SBA-15 silica matrix via direct synthesis. It was demonstrated through the synthesis and characterization of a series of molybdenum containing SBA-15 mesoporous silica catalysts prepared with and without diammonium hydrogen phosphate (DHP) as an additive. Catalysts prepared with DHP show a 2-3 times increase in incorporation of molybdenum in the silica matrix and pore size enlargement. The synthesized catalysts were characterized using nitrogen sorption, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma-optical emission spectroscopy (ICP-OES). The catalytic activity of catalysts prepared with DHP for alcoholysis of epoxides was superior than the catalyst prepared without DHP. Alcoholysis of epoxides was demonstrated for a range of alcohols and epoxides under ambient conditions in as little as 30 min with high selectivity.
Efficient and regioselective ring-opening of epoxides with alcohols and sodium azide by using catalytic amounts of gacl3/polyvinylpyrrolidone
Pourali, Ali Reza,Ghayeni, Samaneh,Afghahi, Fatemeh
, p. 1741 - 1744 (2013/07/26)
A new polymeric catalyst was prepared by supporting GaCl3 on cross-linked polyvinylpyrrolidone (GaCl3/ PVP). This catalyst was employed for efficient and regioselective ring-opening reaction of epoxides by various alcohols under solvent-free conditions at room temperature. In our procedure, this heterogeneous catalyst was used at neutral and mild reaction conditions to afford high yields of β-alkoxy alcohols. Also, regioselective conversion of epoxides to β-azidohydrines was accomplished by sodium azide in MeOH in the presence of GaCl3/PVP at room temperature. GaCl3/PVP is a non-hygroscopic and recoverable catalyst and is easily separated from reaction mixture by a simple filtration and re-used repeatedly. Also, this catalyst has good handling and can be stored for long time without any reducing of its reactivity.
Mild and efficient ring opening of epoxides catalyzed by potassium dodecatungstocobaltate(III)
Tangestaninejad, Shahram,Moghadam, Majid,Mirkhani, Valiollah,Yadollahi, Bahram,Mirmohammadi, S. Mohammad R.
, p. 235 - 242 (2007/10/03)
Efficient ring opening of epoxides under mild conditions is reported. Potassium dodecatungstocobaltate(III) trihydrate was used as an efficient catalyst for the alcoholysis and acetolysis of epoxides. Conversion of epoxides to thiiranes was also performed efficiently in the presence of this catalyst. Springer-Verlag 2005.
Aluminium triflate: A remarkable Lewis acid catalyst for the ring opening of epoxides by alcohols
Bradley,Williams,Lawton, Michelle
, p. 3269 - 3272 (2007/10/03)
Al(OTf)3 was found to be an extremely effective catalyst (at ppm levels) for ring opening reactions of epoxides using a range of alcohols. The Royal Society of Chemistry 2005.
Rapid and efficient ring opening of epoxides catalyzed by a new electron deficient tin(IV) porphyrin
Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Shaibani, Reza
, p. 6105 - 6111 (2007/10/03)
The new electron deficient tin(IV) tetraphenylporphyrinato trifluoromethanesulfonate, [SnIV(tpp)(OTf)2], was used as an efficient catalyst for the alcoholysis, hydrolysis and acetolysis of epoxides. Conversion of epoxides to thiiranes and acetonides were also performed efficiently in the presence of this catalyst.
Silica sulfuric acid; an efficient and reusable catalyst for regioselective ring opening of epoxides by alcohols and water
Salehi, Peyman,Dabiri, Minoo,Zolfigol, Mohammad Ali,Fard, Mohammad Ali Bodaghi
, p. 1113 - 1121 (2007/10/03)
The nucleophilic ring opening reactions of epoxides by aliphatic alcohols and water are achieved efficiently in the presence of catalytic amounts of silica sulfuric acid with high degree of regioselectivity. The catalyst is reusable and can be applied several times without any decrease in the yield of reactions.
Efficient regio- and stereoselective ring opening of epoxides with alcohols, acetic acid and water catalyzed by ammonium decatungstocerate(IV)
Mirkhani, Valiollah,Tangestaninejad, Shahram,Yadollahi, Bahram,Alipanah, Ladan
, p. 8213 - 8218 (2007/10/03)
Epoxides can be cleaved in a regio- and stereoselective manner under neutral conditions with alcohols and acetic acid in the presence of catalytic amounts of decatungstocerate(IV) ion, ([CeW10O36] 8-), affording the corresponding β-alkoxy and β-acetoxy alcohols in high yields. In water, ring opening of epoxides occurs with this catalyst to produce the corresponding diols in good yields.
