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Condensation Reaction (condensation + reaction)
Kinds of Condensation Reaction Selected AbstractsAn Organocatalytic Domino Thia-Michael/Aldol Condensation Reaction: Highly Enantioselective Synthesis of Functionalized DihydrothiophenesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Jie Tang Abstract An organocatalytic domino thia-Michael/aldol condensation reaction of ,, ,-unsaturated aldehydes with 1, 4-dithiane-2,5-diol catalyzed by chiral diphenylprolinol TMS ether has been developed, which provides a new practical and direct route to chiral dihydrothiophenes with high yields (up to 90%) and excellent enantioselectivities (up to>99% ee). The catalytic mechanism of the domino reaction was further confirmed through the APCI-MS detection of proposed reaction intermediates. [source] A Biocompatible Condensation Reaction for the Labeling of Terminal Cysteine Residues on Proteins,ANGEWANDTE CHEMIE, Issue 51 2009Hongjun Ren Dr. Lebendig markiert: Eine Proteinmarkierungsmethode, die einen einzelnen Aminosäurelinker in Form eines N-terminalen Cysteinrests sowie niedermolekulare Sonden mit einer Cyanbenzothiazol(CBT)-Einheit verwendet, wurde für die spezifische Fluoreszenzmarkierung von Proteinen in vitro und auf der Oberfläche lebender Zellen eingesetzt (siehe Schema). Diese einfache Ligationsreaktion verläuft hoch spezifisch unter physiologischen Bedingungen. Rd: ein Rhodamin-Farbstoff; TEV: Tabakmosaikvirus. [source] ChemInform Abstract: Indium Modified Mesoporous Zeolite AlMCM-41 as a Heterogeneous Catalyst for the Knoevenagel Condensation Reaction.CHEMINFORM, Issue 40 2010Santosh S. Katkar Abstract The indium-modified mesoporous zeolite AlMCM-41 is used as heterogeneous catalyst for the Knoevenagel reaction of aromatic aldehydes (I) and activated methylene compounds (II). [source] ChemInform Abstract: A Novel One-Pot Three-(in situ Five)-Component Condensation Reaction: An Unexpected Approach for the Synthesis of Tetrahydro-2,4-dioxo-1H-benzo[b][1,5]diazepine-3-yl-2-methylpropanamide Derivatives.CHEMINFORM, Issue 48 2009Ahmad Shaabani 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: Efficient Synthesis of Dibenzo[a,c]cyclohepten-5-ones via a Sequential Suzuki,Miyaura Coupling and Aldol Condensation Reaction.CHEMINFORM, Issue 39 2009Young Lok Choi 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: A Novel Pyridine-Based Three-Component Condensation Reaction: Synthesis of Highly Substituted Quinolizines.CHEMINFORM, Issue 24 2008Ahmad Shaabani 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] Template Synthesis of Peptidomimetics Composed of Aspartic Acid Moiety by Ugi Four-Component Condensation Reaction.CHEMINFORM, Issue 49 2005Xin Zhang Abstract For Abstract see ChemInform Abstract in Full Text. [source] Unexpected Condensation Reaction of Two Units of 1,2-Dihydrophosphinine 1-Oxides in the Presence of Tetracyanoethylene.CHEMINFORM, Issue 21 2003Gyoergy Keglevich Abstract For Abstract see ChemInform Abstract in Full Text. [source] One-Pot Three-Component Condensation Reaction in Water: An Efficient and Improved Procedure for the Synthesis of Furo[2,3-d]pyrimidine-2,4(1H,3H)-diones.CHEMINFORM, Issue 7 2003Ahmad Shaabani Abstract For Abstract see ChemInform Abstract in Full Text. [source] La(O-iPr)3 Catalyzed Three-Component Condensation Reaction: A Convenient Synthesis of N,N-Dialkyl-,-cyanoamines.CHEMINFORM, Issue 1 2003Peipei Sun No abstract is available for this article. [source] ChemInform Abstract: Mn(OAc)3×2H2O-Mediated Three-Component, One-Pot Condensation Reaction: An Efficient Synthesis of 4-Aryl-Substituted 3,4-Dihydropyrimidin-2-ones.CHEMINFORM, Issue 4 2002K. Ananda Kumar 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: Application of the Ugi Four-Component Condensation Reaction for the Synthesis of ,,,- and ,,,-Dipeptides Substituted with Fluoroarylalkyl Pendent Groups.CHEMINFORM, Issue 18 2001Norio Shibata 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] Rapid Organocatalytic Aldehyde-Aldehyde Condensation ReactionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 25 2007Anniina Erkkilä Abstract We report the results of the systematic optimization of the ,-methylenation of aldehydes with aqueous formaldehyde. A simple combination of a secondary amine catalyst and a weak acid co-catalyst has been identified, allowing access to ,-substituted acroleins in a matter of minutes. In the absence of formaldehyde, the catalytic system promoted the self-condensation reaction of ,,,-unsaturated aldehydes. Both of these reactions exhibited linear relationships between co-catalyst acidities and reaction rates. A second-order dependence of catalyst concentration was observed, pointing to the involvement of two molecules of the ammonium catalyst in the rate-determining step. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] ChemInform Abstract: Synthesis of Novel Dendritic 2,2,-Bipyridine Ligands and Their Application to Lewis Acid Catalyzed Diels,Alder and Three-Component Condensation Reactions.CHEMINFORM, Issue 8 2008Takahito Muraki 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] Condensation Reactions at the Methylene Group of 1-(4-Nitrophenyl)pyrrolin-2-one and 1-(4-Nitrophenyl)pyrrolin-2-onium Perchlorate.CHEMINFORM, Issue 17 2007M. A. Sibiryakova 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] Condensation Reactions of Various Nucleophiles with 3-Formylchromone (I)CHEMINFORM, Issue 19 2006V. B. Halnor 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] KHSO4 -Mediated Condensation Reactions of tert-Butanesulfinamide with Aldehydes.CHEMINFORM, Issue 41 2005Preparation of tert-Butanesulfinyl Aldimines. Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Lewis Acid Catalyzed Three-Component Condensation Reactions of Aldehydes, Alkoxysilanes, and Allenylsilanes: Synthesis of ,-Propargyl Ethers.CHEMINFORM, Issue 26 2002Lui Niimi 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: On Condensation Reactions of Aceanthrene Quinone: Novel Heterocycles.CHEMINFORM, Issue 19 2002Atef M. Amer 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: Henry and Knoevenagel Type Condensation Reactions Initiated by Tetraethylammonium Superoxide in Aprotic Medium.CHEMINFORM, Issue 33 2001Ajay Kumar Shukla 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] Carboxyl terminated polyamide 12 chain extension by reactive extrusion using a dioxazoline coupling agent.POLYMER ENGINEERING & SCIENCE, Issue 12 2002Part II: Effects of extrusion conditions Condensation reactions between a carboxyl terminated polyamide 12 and a dioxazoline carried out by reactive extrusion have been characterized in the first part of this study. In the present paper, we focus on the influence of extrusion conditions on reaction progress. Influences of screw profile, screw speed, barrel temperature and feed rate have been established. The use of a flow computation software permitted confirmation of the importance of thermal and mechanical degradations in the condensation process. [source] Synthesis and characterization of 4,4,-dihydroxy-,-methylstilbene crystalCRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2006K. Rameshbabu Abstract 4,4,-dihydroxy-,-methylstilbene (DHAMS) was synthesized by condensation reaction with chloroacetone and phenol in the presence of concentrated sulfuric acid, and has been successfully grown by solution growth technique. This is the first report in the literature on the crystallization of DHAMS and exhibited the birefringent melt (liquid crystal property) of the optical properties. FTIR and FTNMR studies are in accordance with the structure. Good quality crystals were grown by slow evaporation technique by acetone as solvent. A transmission spectrum of the crystal was obtained in the region of 285 nm. The structural and optical properties were studied. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Titanium dioxide nanoparticles-coated column for capillary electrochromatographic separation of oligopeptidesELECTROPHORESIS, Issue 21 2005Yi-Ling Hsieh Abstract A novel column made through the condensation reaction of TiO2 nanoparticles (TiO2,NPs) with silanol groups of the fused-silica capillary is described. EOF measurements under various buffer constitutions were used to monitor the completion of reactions. The results indicated that the EOF was dependent on the interactions between buffers and the bonded TiO2,NPs. With formate/Tris buffer, EOF reversal at pH below,5 and cathodic EOF at pH above,5 were indicated. The pI of the bonded TiO2,NPs was found at ,ph,5. Only cathodic EOF was illustrated by substituting the mobile phase with either glutamate or phosphate buffer. It was elucidated that both glutamate and phosphate buffer yield a negative charge layer on the surface of TiO2,NPs attributable to the formation of a titanium complex. The CEC performance of the column was tested with angiotensin-type oligopeptides. Some parameters that would affect the retention behavior were investigated. The interactions between the bonded phases and the analytes were explicated by epitomized acid,base functional groups of the oligopepetides and the speciation of the surface oxide in different pH ranges. The average separation efficiencies of 3.1×104,plates/m is readily achieved with a column of 70,cm (50,cm)×50,,m,ID under an applied voltage of 15,kV, phosphate buffer (pH,6.0, 40,mM), and UV detection at 214,nm. [source] Self-Assembled Lanthanide Salicylaldimines with a Unique Coordination ModeEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2010gorzata T. Kaczmarek Abstract New lanthanide salicylaldimine complexes of the formula [Ln(H2L)3(NO3)3](H2L), where Ln = La3+ (1), Nd3+ (2), Eu3+ (3), Gd3+ (4), Ho3+ (5), Er3+ (6), Tb3+ (7) or Yb3+ (8), and H2L = N,N,-bis(salicylidene)-4-methyl-1,3-phenylenediamine, were formed in a self-assembly process involving the lanthanide template-induced one-step [2+1] Schiff base condensation reaction between salicylaldehyde and 4-methyl-1,3-phenylenediamine. The unusual coordination pattern of salen-type ligands in these complexes, in which the three potentially tetradentate N2O2 salicylaldimines function as undeprotonated, monodentate, exclusively O-donor ligands without involving the nitrogen atoms in the coordination environment, was proved by single-crystal X-ray diffraction analysis and correlated with spectroscopic characterization. In this species with the nine-coordinate distorted tricapped trigonal prism geometry, the nitrates act as bidentate chelators occupying six coordination sites and leaving the remaining sites available for salicylaldimine ligands formed in situ in the template process. The additional salicylaldimine molecule acts as a guest for the salicylaldimine complex host and stabilizes the overall self-assembled supramolecular network. [source] One-Pot Synthesis of 3-Aryltetramic AcidsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2010Aurélie Mallinger Abstract Tetramic acids substituted in the 3-position by various aryl groups were prepared in one-pot from amino esters and methyl arylacetates, by treatment with potassium tert -butoxide. A tandem process, involving the formation of an amide and a condensation reaction, is likely to occur. N -Unsubstituted tetramic acids were obtained from adducts containing a N -(2,4-dimethoxybenzyl) group. [source] Highly Efficient Fluorine-Promoted Intramolecular Condensation of Benzo[c]phenanthrene: A New Prospective on Direct Fullerene SynthesisEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 36 2009Konstantin Yu. Abstract Various functional groups have been tested as alternative promoters of the intramolecular condensation of benzo[c]phenanthrene under flash vacuum pyrolysis conditions. Methyl and fluorine functionalization were found to be promising approaches. Unexpectedly high selectivity was observed in the cyclization of fluorinated benzo[c]phenanthrenes. The mechanism for the condensation reaction and the advantages of fluorine as a promoter for the rational synthesis of fullerenes are discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Synthesis and Physicochemical Characterization of meso -Functionalized Corroles: Precursors of Organic,Inorganic Hybrid MaterialsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 21 2005Jean-Michel Barbe Abstract Cobalt(III) corroles exhibit an infinite selectivity for the coordination of carbon monoxide towards dioxygen and dinitrogen. This peculiar property thus allows their use as sensing devices for CO detection. Here are described the syntheses and physico-chemical characterization of meso mono-, bis- and tris(triethoxysilyl)-functionalized corroles, precursors of organic,inorganic materials. The corrole ring formation was achieved in every case using the "2+1" method involving the reaction of two equivalents of an encumbered dipyrromethane with one equivalent of an aromatic aldehyde in the presence of a catalytic amount of trifluoroacetic acid. The functionalization of the corrole by triethoxysilyl chains was carried out by a condensation reaction of an isocyanate, bearing a triethoxysilyl termination, either on an amino or hydroxy group. Each final compound and intermediate were characterized by various physico-chemical techniques such as 1H NMR, UV/Vis, MALDI/TOF or EI mass spectrometry and elemental analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] A Simple Route to a Pyridinyl[2.2]paracyclophaneEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2005Henning Hopf Abstract 4-Acetyl[2.2]paracyclophane (1) is converted into the nitrone 2 by treatment with N -methylhydroxylamine·hydrochloride. When 2 is reacted with (E)-1,2-dibenzoylethene (4) the pyridinyl[2.2]paracyclophane 13 is formed in a novel condensation reaction. The structures of 2 and 13, and the mechanism of formation of the latter are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Convergent Approaches to Saudin IntermediatesHELVETICA CHIMICA ACTA, Issue 8 2003Raquel Different convergent approaches to the highly oxygenated sesquiterpene natural product saudin (1), has been investigated. Our strategy has included a Michael addition and aldol condensation reaction as key steps. During the synthetic development, we have found serious steric hindrance when an , -Me-substituted alkyl vinyl ketone was used. Such steric hindrance has been overcome by synthesizing the vinyl ketone 16 through an anionic fragmentation, which was carefully studied. Finally, the intermediate 18 has been synthesized in a one-pot reaction from the vinyl ketone 16 and has been cyclized to obtain the promising tricyclic intermediate 20. [source] An Organocatalytic Domino Thia-Michael/Aldol Condensation Reaction: Highly Enantioselective Synthesis of Functionalized DihydrothiophenesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Jie Tang Abstract An organocatalytic domino thia-Michael/aldol condensation reaction of ,, ,-unsaturated aldehydes with 1, 4-dithiane-2,5-diol catalyzed by chiral diphenylprolinol TMS ether has been developed, which provides a new practical and direct route to chiral dihydrothiophenes with high yields (up to 90%) and excellent enantioselectivities (up to>99% ee). The catalytic mechanism of the domino reaction was further confirmed through the APCI-MS detection of proposed reaction intermediates. [source] |