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Primary Alcohols (primary + alcohol)
Selected AbstractsDirect Functionalization of Arenes by Primary Alcohol Sulfonate Esters Catalyzed by Gold(III).CHEMINFORM, Issue 9 2005Zhangjie Shi No abstract is available for this article. [source] Iron Chloride/4-Acetamido-TEMPO/Sodium Nitrite-Catalyzed Aerobic Oxidation of Primary Alcohols to the AldehydesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2010Weili Yin Abstract A variety of 4-substituted 2,2,6,6-tetramethylpiperidyl-1-oxy (TEMPO) derivatives has been screened for their ability in the oxidation of primary alcohols to the aldehydes with dioxygen under mild conditions. An evaluation of the efficiency of these 4-substituted TEMPO derivatives in the alcohol oxidation may allow an insight into the effect of the structural variations of TEMPO on the oxidation of alcohols, which should facilitate catalyst design and screening efforts. Based on the screening results of 4-substituted TEMPO derivatives, the catalyst comprised of 4-acetamido-TEMPO, iron chloride and sodium nitrite, has been developed for the highly efficient oxidation of a wide range of primary alcohols including primary aliphatic alcohols to the corresponding aldehydes under mild conditions. [source] One-Pot Synthesis of Carbamoyl Azides Directly from Primary Alcohols and Oxidation of Secondary Alcohols to Ketones Using Iodobenzene Dichloride in Combination with Sodium AzideADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Xiao-Qiang Li Abstract An effective synthesis of carbamoyl azides directly from primary alcohols using iodobenzene dichloride in combination with sodium azide has been developed. Moreover, the same regent combination was also efficient for the oxidation of secondary alcohols to the corresponding ketones. [source] Titelbild: Catalytic Oxidative Synthesis of Nitriles Directly from Primary Alcohols and Ammonia (Angew. Chem.ANGEWANDTE CHEMIE, Issue 34 200934/2009) Trägerfixiertes Rutheniumhydroxid erwies sich als effizienter Heterogenkatalysator für die aerobe oxidative Synthese von Nitrilen, wichtigen Ausgangsverbindungen für die Produktion von Pharmaka, Agro- und Feinchemikalien. N. Mizuno et,al. zeigen in ihrer Zuschrift auf S.,6404,ff., dass mit diesem Verfahren Nitrile direkt aus Alkoholen oder Aldehyden und Ammoniak hergestellt werden können, was es zu einer neuen Möglichkeit für eine "grüne" Nitrilsynthese macht. [source] Catalytic Oxidative Synthesis of Nitriles Directly from Primary Alcohols and Ammonia,ANGEWANDTE CHEMIE, Issue 34 2009Takamichi Oishi Gute Grundlage: Der Rutheniumhydroxid-Trägerkatalysator Ru(OH)x/Al2O3 vermittelt effizient die aerobe oxidative Synthese von Nitrilen direkt aus primären Alkoholen (oder Aldehyden) und Ammoniak. Der zurückgewonnene Katalysator konnte ohne merklichen Leistungsverlust wiederverwendet werden. [source] ChemInform Abstract: Iron Chloride/4-Acetamido-TEMPO/Sodium Nitrite-Catalyzed Aerobic Oxidation of Primary Alcohols to the Aldehydes.CHEMINFORM, Issue 23 2010Weili Yin Abstract 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. [source] ChemInform Abstract: TEMPO-Mediated Oxidation of Primary Alcohols to Carboxylic Acids by Exploitation of Ethers in an Aqueous,Organic Biphase System.CHEMINFORM, Issue 52 2009Zhen-Wu Mei Abstract ChemInform 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. [source] ChemInform Abstract: Catalytic Oxidative Synthesis of Nitriles Directly from Primary Alcohols and Ammonia.CHEMINFORM, Issue 52 2009Takamichi Oishi Abstract ChemInform 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. [source] ChemInform Abstract: Iridium-Catalyzed Coupling Reaction of Primary Alcohols with 1-Aryl-1-propynes Leading to Secondary Homoallylic Alcohols.CHEMINFORM, Issue 49 2009Yasushi Obora Abstract ChemInform 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. [source] ChemInform Abstract: Recyclable Gold Nanoparticle Catalyst for the Aerobic Alcohol Oxidation and C,C Bond Forming Reaction Between Primary Alcohols and Ketones under Ambient Conditions.CHEMINFORM, Issue 23 2009Sungjin Kim Abstract ChemInform 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. [source] ChemInform Abstract: An Efficient Method for the Selective Iridium-Catalyzed Monoalkylation of (Hetero)aromatic Amines with Primary Alcohols.CHEMINFORM, Issue 32 2008Benoit Blank Abstract ChemInform 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. [source] ChemInform Abstract: CuCl Catalyzed Selective Oxidation of Primary Alcohols to Carboxylic Acids with tert-Butyl Hydroperoxide at Room Temperature.CHEMINFORM, Issue 30 2008Sreedevi Mannam Abstract ChemInform 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. [source] The ,-Alkylation of Methyl Ketones with Primary Alcohols Promoted by Nickel Nanoparticles under Mild and Ligandless Conditions.CHEMINFORM, Issue 48 2007Francisco Alonso Abstract ChemInform 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. [source] A Mild and Efficient Chemoselective Protection of Primary Alcohols as Pivaloyl Esters Using La(NO3)3×6H2O as a Catalyst under Solvent-Free Conditions.CHEMINFORM, Issue 45 2007P. Prabhakar Abstract ChemInform 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. [source] Microwave-Assisted One-Pot Tandem Reactions for Direct Conversion of Primary Alcohols and Aldehydes to Triazines and Tetrazoles in Aqueous Media.CHEMINFORM, Issue 34 2007Jiu-Jie Shie Abstract ChemInform 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. [source] N-Hydroxysuccinimide-Promoted Oxidation of Primary Alcohols and Aldehydes to Form Active Esters with Hypervalent(III) Iodine.CHEMINFORM, Issue 44 2006Naiwei Wang Abstract ChemInform 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. [source] A Solid-Phase Self-Organized Catalyst of Nanopalladium with Main-Chain Viologen Polymers: ,-Alkylation of Ketones with Primary Alcohols.CHEMINFORM, Issue 32 2006Yoichi M. A. Yamada Abstract ChemInform 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. [source] Direct Oxidative Conversion of Primary Alcohols to Nitriles Using Molecular Iodine in Ammonia Water.CHEMINFORM, Issue 40 2005Naoshi Mori No abstract is available for this article. [source] Asymmetric Synthesis of Secondary Alcohols from Primary Alcohols via Intramolecular Carbenoid C,H Insertion Catalyzed by Rhodium(II) 3-Phenylcholestane-2-carboxylate.CHEMINFORM, Issue 33 2004Cheol Hee Hwang No abstract is available for this article. [source] Highly Efficient Liquid-Phase Oxidation of Primary Alcohols to Aldehydes with Oxygen Catalyzed by Ru,Co Oxide.CHEMINFORM, Issue 41 2003Mehdi Musawir Abstract For Abstract see ChemInform Abstract in Full Text. [source] Iridium-Catalyzed Oppenauer Oxidations of Primary Alcohols Using Acetone or 2-Butanone as Oxidant.CHEMINFORM, Issue 26 2003Takeyuki Suzuki Abstract For Abstract see ChemInform Abstract in Full Text. [source] Controlled Release of Perfumery Alcohols by Neighboring-Group Participation.HELVETICA CHIMICA ACTA, Issue 8 20032-(Hydroxymethyl)-, 2-Carbamoylbenzoates, Comparison of the Rate Constants for the Alkaline Hydrolysis of 2-Acyl- A series of 2-acylbenzoates 1 and 2, 2-(hydroxymethyl)benzoates 3, 2-carbamoylbenzoates 4,6, as well as the carbamoyl esters 7 or 8 of maleate or succinate, respectively (see Fig.,2), were prepared in a few reaction steps, and the potential use of these compounds as chemical delivery systems for the controlled release of primary, secondary, and tertiary fragrance alcohols was investigated. The rate constants for the neighboring-group-assisted alkaline ester hydrolysis were determined by anal. HPLC in buffered H2O/MeCN solution at different pH (Table,1). The rates of hydrolysis were found to depend on the structure of the alcohol, together with the precursor skeleton and the structure of the neighboring nucleophile that attacks the ester function. Primary alcohols were released more rapidly than secondary and tertiary alcohols, and benzoates of allylic primary alcohols (e.g., geraniol) were hydrolyzed 2,4 times faster than their homologous saturated alcohols (e.g., citronellol). For the same leaving alcohol, 2-[(ethylamino)carbonyl]benzoates cyclized faster than the corresponding 2-(hydroxymethyl)benzoates, and much faster than their 2-formyl and 2-acetyl analogues (see, e.g., Fig.,4). Within the carbamoyl ester series, 2-[(ethylamino)carbonyl]benzoates were found to have the highest rate constants for the alkaline ester hydrolysis, followed by unsubstituted 2-(aminocarbonyl)benzoates, or the corresponding isopropyl derivatives. To rationalize the influence of the different structural changes on the hydrolysis kinetics, the experimental data obtained for the 2-[(alkylamino)carbonyl]benzoates were compared with the results of density-functional computer simulations (Table,2 and Scheme,4). Based on a preliminary semi-empirical conformation analysis, density-functional calculations at the B3LYP/6-31G** level were carried out for the starting precursor molecules, several reaction intermediates, and the cyclized phthalimides. For the same precursor skeleton, these simple calculations were found to model the experimental data correctly. With an understanding of the influence of structural parameters on the rate constants obtained in this work, it is now possible to influence the rates of hydrolysis over several orders of magnitude, to design tailor-made precursors for a large variety of fragrance alcohols, and to predict their efficiency as controlled-release systems in practical applications. [source] Synthesis and Electrochemical Study of an Original Copper(II)-Capped Salen,Cyclodextrin ComplexEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29 2010Elise Deunf Abstract A new metallocapped cyclodextrin (CD) was synthesized by the regioselective debenzylation, induced by diisobutylaluminium hydride (DIBAL-H), of perbenzylated cyclodextrins. This reaction allowed for the efficient preparation of an unprecedented CD,salen type copper(II) complex. The electrochemical behavior of both the bound and unbound CD,salen compounds was investigated by cyclic voltammetry. Notably, it was shown that the presence of tert -butyl groups at the ortho - and para -positions of the salen aromatic rings stabilized the copper(II) phenoxyl radical species that was generated upon the one-electron oxidation of the starting compound. Importantly, this stabilization remained effective when the salen-type ligand was covalently attached to the CD. This allowed for investigations of the reactivity of the copper(II) phenoxyl radical complex towards a primary alcohol to be performed by cyclic voltammetry. This reaction can be considered as mimicking the behavior of galactose oxidase. However, under these conditions, no reactivity was observed in the presence of benzyl alcohol. This may be due to distortion, either of the initially square planar salen ligand after its grafting to the CD primary face, and/or of the CD itself. On the other hand, the electrochemical reduction of the un-grafted copper(II) salen-type ligand led to a transient anionic species that exhibited significant stability on the time-scale of the slow cyclic voltammetry measurement in the absence of the CD, but was unstable in the presence of the CD. In the latter case, it was demonstrated that the anionic species was protonated by the CD. Importantly, this protonation was not fast enough to prevent catalytic activation of iodomethane by the electro-generated copper(I)-capped salen CD complex. [source] Synthesis of an Optically Active Decahydro-6-isoquinolone Scaffold with a Quaternary StereocenterEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 12 2004Jens Christoffers Abstract A straightforward synthesis of optically active decahydro-6-isoquinolone derivative 3, containing a quaternary stereocenter, is reported. The starting (R)-configured enantiopure enone 2, which is readily accessible through a copper-catalyzed, L -valine amide mediated Michael reaction and a subsequent Robinson annulation, was hydrogenated with Pd/C in iPrOH to give the decahydroisoquinolone 4. Treatment of 4 with ethyleneglycol in the presence of PPTS yielded the dioxolane-protected derivative 7. A sequence of ester reduction with LiAlH4 and subsequent Ley oxidation of the resulting primary alcohol 10 accomplished the synthesis. Enantiomerically pure aldehyde 3, with three groups for further functionalization, was thus obtained in 63% overall yield. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] A Novel Proline-Valinol Thioamide Small Organic Molecule for a Highly Enantioselective Direct Aldol ReactionADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Bing Wang Abstract A new prolinethioamide compound 4, prepared from readily available natural amino acid L -proline and amino alcohol L -valinol, has been found to be an active catalyst for the direct aldol reaction of various aldehydes with acetone, cyclohexanone or cyclopentanone at 0,°C. Using only 2,mol% loading of this organocatalyst, the reaction could give high enantioselectivity with up to 96% enantiomeric excess for the reaction of 2-nitrobenzaldehyde with acetone. And as for the cyclohexanone, the excellent diastereoselectivity (anti/syn: 99/1) and enantioselectivity (99% ee) could be achieved when reacted with 3-nitrobenzaldehyde in water in the presence of this thioamide 4. This structurally simple catalyst is a highly efficient prolinethioamide derivative, and the terminal hydroxy group in this catalyst is a primary alcohol which is different from the previously reported prerequisite secondary or tertiary alcohol of prolinamides. Our results suggest a new strategy in the design of diversiform organic catalysts for direct asymmetric aldol reactions and related transformations. [source] TEMPO and Carboxylic Acid Functionalized Imidazolium Salts/Sodium Nitrite: An Efficient, Reusable, Transition Metal-Free Catalytic System for Aerobic Oxidation of AlcoholsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2009Cheng-Xia Miao Abstract An effective catalytic system comprising a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) functionalized imidazolium salt ([Imim-TEMPO]+,X,), a carboxylic acid substituted imidazolium salt ([Imim-COOH]+,X,), and sodium nitrite (NaNO2) was developed for the aerobic oxidation of aliphatic, allylic, heterocyclic and benzylic alcohols to the respective carbonyl compounds with excellent selectivity up to >99%, even at ambient conditions. Notably, the catalyst system could preferentially oxidize a primary alcohol to the aldehyde rather than a secondary alcohol to the ketone. Moreover, the reaction rate is greatly enhanced when a proper amount of water is present. And a high turnover number (TON 5000) is achieved in the present transition metal-free aerobic catalytic system. Additionally, the functionalized imidazolium salts are successfully reused at least four times. This process thus represents a greener pathway for the aerobic oxidation of alcohols into carbonyl compounds by using the present task-specific ionic liquids in place of the toxic and volatile additive, such as hydrogen bromide, bromine, or hydrogen chloride (HBr, Br2 or HCl), which is commonly required for the transition metal-free aerobic oxidation of alcohols. [source] Synthesis of 14C-labeled and tritiated AMPA potentiator LY450108JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 2 2005Boris A. Czeskis Abstract Asymmetric synthesis of AMPA potentiator LY450108-[14C] containing 14C-label attached to the chiral center of the molecule, was accomplished based on Evans' chiral oxazolidinone auxiliary method. Diastereoselective methylation of p -nitrophenylacetic acid derivative was used as a key step. The auxiliary was reductively removed, and the resulting primary alcohol was converted into the corresponding amine. Its sulfonylation, reduction of the aromatic nitro group, and acylation with 3,5-difluorobenzoyl chloride led to the final product. The synthesis of tritiated LY450108 is also detailed. Copyright © 2005 John Wiley & Sons, Ltd. [source] Discovery of New Biocatalysts for the Glycosylation of Terpenoid ScaffoldsCHEMISTRY - A EUROPEAN JOURNAL, Issue 22 2008Lorenzo Caputi Abstract The synthesis of terpenoid glycosides typically uses a chemical strategy since few biocatalysts have been identified that recognise these scaffolds. In this study, a platform of 107 recombinant glycosyltransferases (GTs), comprising the multigene family of small molecule GTs of Arabidopsis thaliana have been screened against a range of model terpenoid acceptors to identify those enzymes with high activity. Twenty-seven GTs are shown to glycosylate a diversity of mono-, sesqui- and diterpenes, such as geraniol, perillyl alcohol, artemisinic acid and retinoic acid. Certain enzymes showing substantial sequence similarity recognise terpenoids containing a primary alcohol, irrespective of the linear or cyclical structure of the scaffold; other GTs glycosylate scaffolds containing secondary and tertiary alcohols; the carboxyl group of other terpenoids also represents a feature that is recognized by GTs previously known to form glucose esters with many different compounds. These data underpin the rapid prediction of potential biocatalysts from GT sequence information. To explore the potential of GTs as biocatalysts, their use for the production of terpenoid glycosides was investigated by using a microbial-based whole-cell biotransformation system capable of regenerating the cofactor, UDP-glucose. A high cell density fermentation system was shown to produce several hundred milligrams of a model terpenoid, geranyl-glucoside. The activities of the GTs are discussed in relation to their substrate recognition and their utility in biotransformations as a complement or alternative to chemical synthesis. [source] Total Synthesis of (+)-Batzelladine A and (,)-Batzelladine D, and Identification of Their Target ProteinCHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2005Jun Shimokawa Abstract Asymmetric total synthesis of batzelladine A (1) and batzelladine D (2) has been achieved. Our synthesis of batzelladines features 1) stereoselective construction of the cyclic guanidine system by means of successive 1,3-dipolar cycloaddition reaction and subsequent cyclization, 2) direct esterification of the bicyclic carboxylic acid 35 with the guanidine alcohol 8 or 59 to construct the whole carbon skeleton of batzelladines, and 3) one-step formation of the ,,,-unsaturated aldehyde 53 from the primary alcohol 47 with tetra- n -propylammoniumperruthenate (TPAP), providing an efficient route to the left-hand bicyclic guanidine alcohol of batzelladine A (1). With the synthetic compounds 1 and 2 in hand, their target protein was examined by using immobilized CD4 and gp120 affinity gels. The results indicated that batzelladines A (1) and D (2) bind specifically to CD4. [source] Hydrido-Osmium(II), -Osmium(IV) and-Osmium(VI) Complexes with Functionalized Phosphanes as Ligands,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 35 2009Birgit Richter Abstract Reaction of five-coordinate [OsHCl(CO)(PiPr3)2] (1) with the chelating phosphane iPr2PCH2CO2Me gave six-coordinate [OsHCl(CO)(PiPr3){,2(P,O)- iPr2PCH2C(=O)OMe}] (2), which upon treatment with CO and O2 afforded the 1:1 adducts [OsHCl(CO)(L)(PiPr3){,(P)- iPr2PCH2CO2Me}] (3, 4) by partial opening of the chelate ring. The vinyl complex [OsCl(CH=CHPh)(CO)(PiPr3){,2(P,O)- iPr2PCH2C(=O)OMe}] (5) was obtained from 2 and PhC,CH by insertion of the alkyne into the Os,H bond. Reaction of 2 with sodium acetate led to metathesis of the anionic ligands and formation of [OsH(,2 -O2CCH3)(CO)(PiPr3){,(P)- iPr2PCH2CO2Me}] (6). Osmium(VI) compounds [OsH6(PiPr2R)2] with R = CH2CH2OMe (12), CH2CO2Me (13) and CH2CO2Et (14), and [OsH6(PiPr3){,(P)- iPr2PCH2CH2NMe2}] (16) were prepared from osmium(IV) precursors and shown to rapidly react with O2 and primary alcohols. Exploratory studies revealed that the catalytic activity of the hexahydrido complexes in the hydrogen transfer reaction from 2-propanol to cyclohexanone and acetophenone depends on the type of the functionalized phosphane and is best for R = CH2CH2OMe. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] | ||||||||||||||||||||||||||||