Catalysts For Organic Reactions Research Articles

ChemInform Abstract: An Efficient Hydrogenation of Various Alkenes Using Scrap Automobile Catalyst.

AbstractA used automobile catalytic converter is taken from a Fiat Siena.

Synthesis, characterization and use of polymer‐supported phase transfer catalyst in organic reactions

AbstractA polymer‐supported (PS) phase transfer catalyst, polyethylene‐g‐quaternary ammonium salt (PE‐g‐QN+), is prepared through a three‐step graft copolymerization of maleic anhydride (MAn) onto polyethylene (PE) by photochemical method using 1% benzophenone (Bz) as photosensitizer. Post grafted acid hydrolysis of polyethylene‐g‐maleic anhydride (PE‐g‐MAn) results in the preparation of PE‐g‐succinic acid which on further treatment with tetrabutylammonium bromide (TBAB) under basic conditions in tetrahydrofuran (THF) gives PE‐g‐QN+. Optimum conditions pertaining to maximum percentage of grafting have been evaluated as a function of concentration of maleic anhydride, amount of photosensitizer, and time of reaction. Maximum percentage of grafting (25%) was obtained using 3.57 mol of MAn and 0.5 mL of 1% Bz in 120 min. The PE and graft copolymers, PE‐g‐MAn, and PE‐g‐QN+ were characterized by FTIR Spectroscopy and thermogravimetric analysis (TGA). The ionic nature of quaternary ammonium salt, PE‐g‐QN+ has also been confirmed by conductance measurements. PE‐g‐QN+ reagent have been used successfully for polymerization, amidation, and esterification reactions. The products obtained were characterized by FTIR and H1NMR spectral methods. The reagent was reused for the further reactions and it was observed that the polymeric reagent polymerize, amidate, and esterificate the compounds successfully but with little lower product yield. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

An efficient hydrogenation of various alkenes using scrap automobile catalyst

An efficient, easy, cheap, convenient, and safe procedure for the reduction of various alkenes to the corresponding alkanes is developed by using scrap automobile catalyst as an efficient hydrogenation catalyst. This procedure not only gives high yields, but also allows recycling of automobile wastes as a catalyst in organic reactions and is representative of green chemistry.

Synthesis, Characterization and Application of Poly(4-vinylpyridine)-Supported Brønsted Acid as Reusable Catalyst for Acetylation Reaction

Poly(4-vinylpyridine)-supported Bronsted acids (P4VP-HX) were prepared by wet impregnation technique. These supported acids were found as efficient heterogeneous green catalysts for acetylation of alcohol, amine and phenol with different catalytic activities. The wide application of P4VP-HX as reusable solid acid catalyst in organic reactions is possible because of its simple preparation and handling, stability, simple work up procedure.

ChemInform Abstract: Recent Uses of Iron Catalysts in Organic Reactions

AbstractReview: 221 refs.

Recent progress in the preparation and application of carbon nanocapsules

In this review paper, the processes for the fabrication of carbon nanoparticles, carbon nanospheres, carbon onions, onion-like carbons and metal-filled carbon nanocapsules are reviewed. These processes include carbon arc discharge, metal catalysed chemical vapour deposition, thermal pyrolysis of organometallics and nanodiamonds, electric arc in liquid (e.g. liquid N2, H2O and organic solvents), and microwave arcing. The applications of both hollow and metal-filled carbon nanocapsules/nanoparticles as x-ray target materials, nanolubricants, broadband electromagnetic wave absorbers, catalysts for organic reactions, electrode materials for batteries and electrochemical immunoassays, biomedical gene/drug transporters, etc are also reviewed. The future prospects are also discussed.

ChemInform Abstract: Zeolites as Catalysts in Organic Reactions: Condensation of Aldehydes with Benzene Derivatives.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Recent Uses of Iron Catalysts in Organic Reactions

Iron catalysts are extensively used in organic reactions in recent years since iron is one of the most abundant metals on earth, consequently one of the most inexpensive, and environmentally friendly ones, and many iron salts and complexes are commercially available. This comprehensive review attempts to cover the advances of iron-catalyzed organic reactions in the literature from 2007 to Sept 2009, particularly focusing on the formation of carbon-carbon bond. Simultaneously, the iron-catalyzed formation of carbon- heteroatom and heteroatom- heteroatom bond also are commented briefly.

1,4-Diazabicyclo[2.2.2]octane (DABCO) as a useful catalyst in organic synthesis

1,4-diazabicyclo[2.2.2]octane (DABCO) has been used in many organic preparations as a good solid catalyst. DABCO has received considerable attention as an inexpensive, eco-friendly, high reactive, easy to handle and non-toxic base catalyst for various organic transformations, affording the corresponding products in excellent yields with high selectivity. In this review, some applications of this catalyst in organic reactions were discussed.

Half sandwich complexes of Ru(II) and complexes of Pd(II) and Pt(II) with seleno and thio derivatives of pyrrolidine: Synthesis, structure and applications as catalysts for organic reactions

The reactions of PhSe −, PhS − and Se 2− with N-{2-(chloroethyl)}pyrrolidine result in N-{2-(phenylseleno)ethyl}pyrrolidine ( L1), N-{2-(phenylthio)ethyl}pyrrolidine ( L2), and bis{2-pyrrolidene- N-yl)ethyl selenide ( L3), respectively, which have been explored as ligands. The complexes [PdCl 2( L1/ L2)] ( 1/ 7), [PtCl 2( L1/ L2)] ( 2/ 8), [RuCl(η 6-C 6H 6)( L1/ L2)][PF 6] ( 3/ 9), [RuCl(η 6- p-cymene)( L1/ L2)][PF 6] ( 4/ 10), [RuCl(η 6- p-cymene)(NH 3) 2][PF 6] ( 5) and [Ru(η 6- p-cymene)( L1)(CH 3CN)][PF 6] 2·CH 3CN ( 6) have been synthesized. The L1– L3 and complexes were found to give characteristic NMR (Proton, Carbon-13 and Se-77). The crystal structures of complexes 1, 3– 6, 9 and 10 have been solved. The Pd–Se and Ru–Se bond lengths have been found to be 2.353(2) and 2.480(11)/2.4918(9)/2.4770(5) Å, respectively. The complexes 1 and 7 have been explored for catalytic Heck and Suzuki–Miyaura coupling reactions. The value of TON has been found up to 85 000 with the advantage of catalyst’s stability under ambient conditions. The efficiency of 1 is marginally better than 7. The Ru-complexes 3 and 9 are good for catalytic oxidation of primary and secondary alcohols in CH 2Cl 2 in the presence of N-methylmorpholine- N-oxide (NMO). The TON value varies between 8.0 × 10 4 and 9.7 × 10 4 for this oxidation. The 3 is somewhat more efficient catalyst than 9.

ChemInform Abstract: Surfactant‐Type Catalysts in Organic Reactions.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Supported Gold Nanoparticles as Catalysts for Organic Reactions

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Lewis Base Catalysis in Organic Synthesis

The legacy of Gilbert Newton Lewis (1875-1946) pervades the lexicon of chemical bonding and reactivity. The power of his concept of donor-acceptor bonding is evident in the eponymous foundations of electron-pair acceptors (Lewis acids) and donors (Lewis bases). Lewis recognized that acids are not restricted to those substances that contain hydrogen (Brønsted acids), and helped overthrow the "modern cult of the proton". His discovery ushered in the use of Lewis acids as reagents and catalysts for organic reactions. However, in recent years, the recognition that Lewis bases can also serve in this capacity has grown enormously. Most importantly, it has become increasingly apparent that the behavior of Lewis bases as agents for promoting chemical reactions is not merely as an electronic complement of the cognate Lewis acids: in fact Lewis bases are capable of enhancing both the electrophilic and nucleophilic character of molecules to which they are bound. This diversity of behavior leads to a remarkable versatility for the catalysis of reactions by Lewis bases.

Supported gold nanoparticles as catalysts for organic reactions

This critical review is intended to attract the interest of organic chemists and researchers on green and sustainable chemistry on the catalytic activity of supported gold nanoparticles in organic transformations. In the general part of this critical review, emphasis is given to the different procedures to form supported gold nanoparticles and to the importance of the support cooperating in the catalysis. Also the convergence of homogeneous and heterogeneous catalysis in the study of gold nanoparticles has been discussed. The core part of this review is constituted by sections in which the reactions catalyzed by supported gold nanoparticles are described. Special emphasis is made on the unique ability of gold catalysts to promote additions to multiple C-C bonds, benzannulations and alcohol oxidation by oxygen (282 references).

β-Cyclodextrin as Supramolecular Catalyst in Organic Synthesis

By the end of the 1960s, the methods for the laboratory-scale preparation of cyclodextrins, their structure, physical and chemical properties had been discovered. Literature survey reveals that cyclodextrins are very interesting, promising molecules in supramolecular chemistry as well as for their industrial importance. In recent years cyclodextrins have been used as catalysts in organic reactions. In this spotlight the use of cyclodextrin in organic reactions as a supramolecular catalyst is highlighted.

Novel Hydrophobic Brønsted Acidic Ionic-liquids as Efficient and Reusable Catalysts for Organic Reactions in Water

Abstract Novel hydrophobic Brønsted acidic ionic liquids (HBAIL) were prepared and utilized as acid catalysts in organic reactions in water. HBAILs were demonstrated, for the first time, to be effective catalysts for Prins cyclization of styrene derivatives in water with a formaldehyde water solution. Many styrene derivatives could be successfully converted to the corresponding 1,3-dioxanes. Other dehydration reactions also proceeded well using HBAILs in water. After reactions, HBAILs could be easily recovered and reused without significant loss of activity.

Heteropoly Acids, Their Salts and Polyoxometalates as Heterogeneous, Efficient and Ecofriendly Catalysts in Organic Reactions: Some Recent Advances

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

Heteropoly acids, their salts and polyoxometalates as heterogenous, efficient and eco-friendly catalysts in organic reactions: Some recent advances

In this review article, some recent advances of applying heteropoly acids and polyoxometalates as heterogeneous, reusable and eco-friendly catalysts in organic synthesis are discussed.

Recent Advances in Organic Synthesis Using Transition Metal-Catalyzed Hydroborations

Among the most significant advances in organic synthesis over the past few decades are those associated with the development of transition metal complexes for their use as catalysts in organic reactions. The discovery that transition metals can also be used to catalyze the addition of B-H bonds to unsaturated substrates has provided the synthetic community with another valuable tool. This review examines recent advances in the field of catalyzed hydroborations and their applications in organic synthesis. Keywords: organoboranes, hydroboration, regioselectivity, chiral oxazaborolidine reagent, catalyst development, enynes, matteson-brown homologation, vinylarenes, deoxygenation, natural products

Preparation of Polyoxetane Resins Having Polyoxirane Segments in the Pendant and Cross-Linking Chains and Uses as Polymeric Solvents for Alkali-Metal Ions

Several polyoxirane–polyoxetane composite resins were prepared by BF3–initiated cationic polymerizatons of α-mono- and α,ω-dioxetanyl-substituted polyoxiranes with an ordinary bisoxetane or without adding it at 0 °C for 50 h. The resins obtained were examined as a phase-transfer catalyst in organic reactions, such as halogen-exchange, Williamson-type etherification, alkene-forming elimination, and C-alkylation of malonic esters, using NaI, KI, NaOH, or KOH as a source of a nucleophile or a base. Thus, it was indicated that the pendant and cross-linking polyoxirane segments acted as polymeric solvents capable of catching sodium and potassium cations in the manner of cooperative coordination. Herein, polyether matrices may play an important role in forming reaction stages, possibly due to self-assembled oxyethylene segments and due to moderately flexible polyoxetane backbones.