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One Pot (one + pot)
Selected AbstractsStereoselective Synthesis of 2-Deoxyglycosides from Sulfanyl Alkenes by Consecutive "One Pot" Cyclization and Glycosylation ReactionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2007Miguel A. Rodríguez Abstract 2-Deoxy-2-iodopyranosides 3, and 9,12 were synthesized from sulfanyl alkenes using a "one pot" consecutive cyclization,glycosylation process. Compared with the stepwise procedure, the "one pot" process gave significantly improved yields with similar or slightly lower selectivities. The "onepot" procedure was applied to the synthesis of 2,6-dideoxy-2-iodoglycoside 22, which was successfully deiodinated to afford the 2,6-dideoxyglycoside 23. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Tandem Enzyme/Gold-Catalysis: From Racemic ,-Allenic Acetates to Enantiomerically Enriched 2,5-Dihydrofurans in One PotADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Martta Asikainen Abstract We report the first example of a tandem kinetic resolution/cycloisomerization of racemic allenic acetates in the presence of Burkholderia cepacia lipase (PS Amano SD) and catalytic amounts of chloroauric acid (HAuCl4) which affords 2,5-dihydrofurans, as well as unreacted starting material, in one pot with high enantiomeric excess and moderate to good yield. [source] ChemInform Abstract: A "One Pot" Synthesis of 2-Aryl-4H-1-benzopyran-4-ones under Coupled Microwave Phase Transfer Catalysis (PTC) and Ultrasonic Irradiation PTC.CHEMINFORM, Issue 29 2008Vijai N. Pathak 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] Microwave-Assisted "Green" Synthesis of 2-Alkyl/Arylbenzothiazoles in One Pot: A Facile Approach to Antitumor Drugs.CHEMINFORM, Issue 12 2007Sukanta Kamila 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] Rare-Earth Silylamide-Catalyzed Selective Dimerization of Terminal Alkynes and Subsequent Hydrophosphination in One Pot.CHEMINFORM, Issue 1 2006Kimihiro Komeyama Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis and Anion-Binding Properties of Novel Redox-Active Calixarene ReceptorsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 25 2008Estelle Métay Abstract A novel synthetic approach towards redox-active calixarene-based receptors is described in which ferrocene fragments were introduced at the lower rim through anion-binding urea or amide connections. These derivatives were prepared in one pot by treating an amine-containing calixarene with ferrocenecarboxylic acid in the presence of diphenylphosphoryl azide and diisopropylethylamine. This method allows a convergent approach to these receptors and is readily adaptable to the introduction of other urea substituents. The anion-binding properties of these artificial receptors have been revealed by NMR spectroscopy and thoroughly investigated by electrochemical methods. We have assessed the importance of the urea,phosphate bonds in the observed electrochemical response by studying receptors in which the ferrocene reporters and binding fragments are closely associated or fully disconnected through a long alkyl chain. The experimental results clearly show the utmost importance of ion-pairing effects in the electrochemical recognition process, which account for most of the transduction signal in organic apolar media. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Stereoselective Synthesis of 2-Deoxyglycosides from Sulfanyl Alkenes by Consecutive "One Pot" Cyclization and Glycosylation ReactionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2007Miguel A. Rodríguez Abstract 2-Deoxy-2-iodopyranosides 3, and 9,12 were synthesized from sulfanyl alkenes using a "one pot" consecutive cyclization,glycosylation process. Compared with the stepwise procedure, the "one pot" process gave significantly improved yields with similar or slightly lower selectivities. The "onepot" procedure was applied to the synthesis of 2,6-dideoxy-2-iodoglycoside 22, which was successfully deiodinated to afford the 2,6-dideoxyglycoside 23. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Chemoselective and Regiospecific Synthesis of Iminospiro- , -lactones from Maleic Anhydride or Citraconic Anhydride and Alkyl Isocyanides with Dialkyl AcetylenedicarboxylatesHELVETICA CHIMICA ACTA, Issue 4 2010Mohammad Bayat Abstract Isocyanides, dialkyl acetylenedicarboxylates (=dialkyl but-2-ynedioates), and anhydrides such as maleic anhydride (=furan-2,3-dione) or citraconic anhydride (=3-methylfuran-2,3-dione) react in one pot to afford novel iminospiro- , -lactones in fairly good yields at room temperature (Schemes,1 and 3). [source] Combining Designer Cells and Click Chemistry for a One-Pot Four-Step Preparation of Enantiopure ,-HydroxytriazolesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Wiktor Szymanski Abstract The multistep catalytic process using designer cells, either added as freshly prepared suspensions or as stable lyophilized powder, and click reaction can be performed in one pot. The sequence of four reactions allows the production of both enantiomers of ,-hydroxytriazoles with high enantiomeric excess. [source] Facile and Efficient Synthesis of Hydrophenanthren-1(2H)-ones and Naphtho[2,1- c]furan-3(1H)-ones by a Palladium-Catalyzed Aryne Annulation StrategyADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Xian Huang Abstract Novel palladium-catalyzed carboannulation reactions of arynes with functionalized vinyl iodides are reported. By applying allyl-substituted iodocycloenones and iodofuranones, a series of hydrophenanthren-1(2H)-ones and naphtho[2,1- c]furan-3(1H)-ones were efficiently constructed in one pot under mild conditions. [source] Tandem Enzyme/Gold-Catalysis: From Racemic ,-Allenic Acetates to Enantiomerically Enriched 2,5-Dihydrofurans in One PotADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Martta Asikainen Abstract We report the first example of a tandem kinetic resolution/cycloisomerization of racemic allenic acetates in the presence of Burkholderia cepacia lipase (PS Amano SD) and catalytic amounts of chloroauric acid (HAuCl4) which affords 2,5-dihydrofurans, as well as unreacted starting material, in one pot with high enantiomeric excess and moderate to good yield. [source] Immobilization of Porphyrinatocopper Nanoparticles onto Activated Multi-Walled Carbon Nanotubes and a Study of its Catalytic Activity as an Efficient Heterogeneous Catalyst for a Click Approach to the Three-Component Synthesis of 1,2,3-Triazoles in WaterADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Hashem Sharghi Abstract An efficient, regioselective, one-pot and two-step synthesis of ,-hydroxy 1,4-disubstituted 1,2,3-triazoles from a wide range of non-activated terminal alkynes and epoxides and sodium azide by way of a three-component click reaction using a catalytic amount of [meso -tetrakis(o -chlorophenyl)porphyrinato]copper(II) (5,mol%) in excellent isolated yields is described. The reactions were performed in water as a green solvent at ambient temperature without any additives. By performing two reaction steps in one pot and purifying only at the final step, this procedure excludes any interim purification of in situ generated organic azide intermediates, which significantly improves the overall yield and reduces the reaction time. To benefit from the recovery and reuse of the catalyst, a new heterogeneous catalyst was prepared by simple and successful impregnation of the catalyst onto activated multi-walled carbon nanotubes (AMWCNT). The heterogeneous catalyst was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic forced microscopy (AFM), and thermogravimetric (TG) analysis to estimate the amount of nitrogen adsorption, and Raman and FT-IR spectroscopy. Leaching experiments after ten successive cycles showed that the catalyst is most strongly anchored to the AMWCNT support. Mechanistically, porphyrinatocopper catalyzes each step of the reaction in different ways as a bifunctional catalyst including epoxide ring opening by azide delivery to epoxide, forming in situ generated 2-azido alcohols followed by activation of the CC triple bond of the starting terminal alkynes by forming a porphyrinatocopper-acetylide intermediate and thereby promoting the [3+2]-cycloaddition reaction as the key step to form the triazole framework. [source] Promiscuous Zinc-Dependent Acylase-Mediated One-Pot Synthesis of Monosaccharide-Containing Pyrimidine Derivatives in Organic MediumADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Qi Wu Abstract A facile one-pot synthesis route to monosaccharide-containing pyrimidine derivatives was developed by combining the two types of catalytic activities of one enzyme in an organic medium, i.e., the Michael addition/acylation activities of zinc-dependent D -aminoacylase (DA) from Escherichia coli. First, the stepwise approach was investigated. DA showed higher activity towards the Michael addition than acylation in this reaction system. The enzymatic Michael additions of pyrimidines to vinyl acrylate proceeded very rapidly and the initial reaction rates for the Michael addition of pyrimidines to vinyl acrylate were 7.2,16.5,mM,min,1. The catalytic specificity of aminoacylases toward Michael addition was demonstrated by the combination of different control experiments. Then, the two steps could be performed in one pot and a single aminoacylase catalyzed one-pot biotransformation was constructed. Using this strategy, a series of saccharide-pyrimidine complexes with potentially biological and pharmacological applications was prepared efficiently. This high Michael addition activity of zinc-dependent aminoacylases and the novel single aminoacylase-catalyzed one-pot synthesis combining two catalytic activities in vitro is of practical significance in expanding the application of enzymes and in the evolution of new biocatalysts. [source] Regioselective Palladium(0)-Catalyzed Cross-Coupling Reactions and Metal-Halide Exchange Reactions of Tetrabromothiophene: Optimization, Scope and LimitationsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009ng Thanh Tůng Abstract The Suzuki reaction of tetrabromothiophene with arylboronic acids provides a regioselective approach to various 5-aryl-2,3,4-tribromothiophenes, symmetrical 2,5-diaryl-3,4-dibromothiophenes, and tetraarylthiophenes. Unsymmetrical 2,5-diaryl-3,4-dibromothiophenes are prepared by Suzuki reaction of 5-aryl-2,3,4-tribromothiophenes. Tetraarylthiophenes containing two different types of aryl groups are obtained by Suzuki reactions of 2,5-diaryl-3,4-dibromothiophenes. During the optimization of the conditions of each individual reaction, the solvent, the catalyst and the temperature play an important role. In several cases, classical conditions [use of tetrakis(triphenylphosphane)palladium(0), Pd(PPh3)4, as the catalyst] gave excellent yields. The yields of those transformations which failed or proceeded sluggishly could be significantly improved by application of a new biarylmonophosphine ligand developed by Buchwald and co-workers. Regioselective metal-halide exchange reactions of tetrabromothiophene provide a convenient approach to various 2,5-disubstituted 3,4-dibromothiophenes. 5-Alkyl-2-trimethylsilyl-3,4-dibromothiophenes could be prepared in one pot by sequential addition of trimethylchlorosilane and alkyl bromides. The reaction of tetrabromothiophene with methyl chloroformate and subsequent Suzuki reactions afforded 3,4-diaryl-2,5-bis(methoxycarbonyl)thiophenes. [source] Highly Convenient, Clean, Fast, and Reliable Sonogashira Coupling Reactions Promoted by Aminophosphine-Based Pincer Complexes of Palladium Performed under Additive- and Amine-Free Reaction ConditionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2009Jeanne Abstract Sequential addition of 1,1,,1,,-phosphinetriyltripiperidine and 1,3-diaminobenzene or resorcinol to toluene solutions of (cyclooctadiene)palladium dichloride [Pd(cod)(Cl)2] under nitrogen in "one pot" almost quantitatively yielded the aminophosphine-based pincer complexes {[C6H3 -2,6-(XP{piperidinyl}2)2]Pd(Cl)} (X=NH 1; X=O 2). Complex 1 (and to a minor extent 2) proved to be efficient Sonogashira catalysts, which allow the quantitative coupling of various electronically deactivated and/or sterically hindered and functionalized aryl iodides and aryl bromides with several alkynes as coupling partners within very short reaction times and low catalyst loadings. Importantly, in contrast to most of the Sonogashira catalysts, which either are both air- and moisture-sensitive and/or require the addition of co-catalysts, such as copper(I) iodide [CuI], for example, or a large excess of an amine, the coupling reactions were carried out without the use of amines, co-catalysts or other aditives and without exclusion of air and moisture. Moreover, the desired products were exclusively formed (no side-products were detected) without employing an excess of one of the substrates. Ethylene glycol and potassium phosphate (K3PO4) were found to be the ideal solvent and base for this transformation. Experimental observations strongly indicate that palladium nanoparticles are not the catalytically active form of 1 and 2. On the other hand, their transformation into another homogeneous catalytically active species cannot be excluded. [source] Nanocrystalline Titanium(IV) Oxide as an Efficient Heterogeneous Catalyst for Tandem Michael and Nucleophilic 1,2-Addition to EnonesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2006Lakshmi Kantam Abstract Nanocrystalline titanium(IV) oxide was found to be an efficient heterogeneous catalyst for the conjugate 1,4-addition of indoles with ,,, - unsaturated ketones to afford ,-indolyl ketones in excellent yields. The subsequent catalytic 1,2-addition of Me3SiCN to carbonyl compounds can be performed in one pot with moderate to good yields. Low sensitivity towards traces of moisture and high tolerance of different functional groups make nanocrystalline titanium(IV) oxide suitable for carrying out multistep synthetic sequences. [source] One-Pot Homogeneous and Heterogeneous Oxidation of Glycerol to Ketomalonic Acid Mediated by TEMPOADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2003Rosaria Ciriminna Abstract Glycerol, an increasingly abundant by-product of biodiesel production, is selectively converted to ketomalonic acid in one pot at pH 10 using NaOCl as regenerating oxidant in water at 2,°C in the presence of catalytic Br, along with the radical TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl). The reaction can also be conducted at completion over a sol-gel silica glass doped with the nitroxyl radical. Considering the stability and versatility of such doped glasses, these materials show real promise as reusable metal-free catalysts for the conversion of a readily available and renewable biofeedstock into a highly valued compound. [source] Microwave-assisted "green" synthesis of 2-alkyl/arylbenzothiazoles in one pot: A facile approach to anti-tumor drugsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2006Sukanta Kamila A series of new 2-alkyl/arylbenzothiazoles has been synthesized on the basis of the potent and selective in vitro anti-tumor properties of 2-(3,4-diethoxyphenyl)-5-fluorobenzothiazole. The synthesis of benzothiazole analogs was achieved via microwave irradiation of a 1:1 mixture of o -aminothiophenol and alkyl/aryl acylacetonitriles at temperature of 200°C for 10 min. The yields are very good to excellent. All the products were characterized by 1H nmr, 13C nmr and elemental analysis. [source] Block copolymers by chemoenzymatic cascade polymerization: A comparison of consecutive and simultaneous reactionsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 14 2006Matthijs de Geus Abstract The synthetic parameters for the chemoenzymatic cascade synthesis of block copolymers combining enzymatic ring-opening polymerization (EROP) and atom transfer radical polymerization (ATRP) in one pot were investigated. A detailed analysis of the mutual interactions between the single reaction components revealed that the ATRP catalyst system could have a significant inhibiting effect on the enzyme activity. The inhibition of the enzyme was less pronounced in the presence of multivalent ligands such as dinonyl bipyridine, which thus could be used in this reaction as an ATRP catalyst. Moreover, the choice of the ATRP monomer was investigated. Methyl methacrylate interfered with EROP by transesterification, whereas t -butyl methacrylate was inert. Block copolymers were successfully synthesized with this cascade approach by the activation of ATRP after EROP by the addition of the ATRP catalyst and, with lower block copolymer yields, by the mixing of all the components before the copolymerization. Adetailed kinetic analysis of the reactions and the structure of the block copolymers showed that the first procedure proceeded smoothly to high block copolymer yields, whereas in the latter a noteworthy amount of the poly(t -butyl methacrylate) homopolymer was detected. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4290,4297, 2006 [source] Synthesis of star-shaped copolymers with methyl methacrylate and n -butyl methacrylate by metal-catalyzed living radical polymerization: Block and random copolymer arms and microgel cores,JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 5 2002Kyung-Youl Baek Abstract Various star-shaped copolymers of methyl methacrylate (MMA) and n -butyl methacrylate (nBMA) were synthesized in one pot with RuCl2(PPh3)3 -catalyzed living radical polymerization and subsequent polymer linking reactions with divinyl compounds. Sequential living radical polymerization of nBMA and MMA in that order and vice versa, followed by linking reactions of the living block copolymers with appropriate divinyl compounds, afforded star block copolymers consisting of AB- or BA-type block copolymer arms with controlled lengths and comonomer compositions in high yields (,90%). The lengths and compositions of each unit varied with the amount of each monomer feed. Star copolymers with random copolymer arms were prepared by the living radical random copolymerization of MMA and nBMA followed by linking reactions. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 633,641, 2002; DOI 10.1002/pola.10145 [source] A one-pot, stereoselective synthesis of 2-ethoxycarbonyl-substituted 1,3-dienes and 1,3-enynes by hydrostannylation,Stille tandem reaction of tributyltin hydride with alkynyl esters and alkenyl or alkynyl halidesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2009Mingzhong Cai Abstract 2-Ethoxycarbonyl-substituted 1,3-dienes and 1,3-enynes can be stereoselectively synthesized in one pot under mild conditions, in good yields, by the palladium-catalyzed hydrostannylation of alkynyl esters, followed by Stille coupling with alkenyl or alkynyl halides, respectively. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||