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One-Pot Preparation (one-pot + preparation)
Selected AbstractsOne-Pot Preparation of [n]Ladderanes by [2, + 2,] PhotocycloadditionEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2005Henning Hopf Abstract A new method for the preparation of [n]ladderanes is presented, based on a one-pot [2,+2,] photocycloaddition of [2.2]paracyclophane pseudo- gem bis(polyene) precursors. [3]- and [5]ladderanes could be isolated and were fully characterized, including their X-ray structure analysis. The overall chemical yields from [2.2]paracyclophane as starting material were found to be 53 % ([3]ladderane) and 38 % ([5]ladderane). Preliminary investigations of their photochromic properties (reversible change from yellow or red to colourless forms) are described. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] One-Pot Preparation of Polymer,Enzyme,Metallic Nanoparticle Composite Films for High-Performance Biosensing of Glucose and GalactoseADVANCED FUNCTIONAL MATERIALS, Issue 11 2009Yingchun Fu Abstract New polymer,enzyme,metallic nanoparticle composite films with a high-load and a high-activity of immobilized enzymes and obvious electrocatalysis/nano-enhancement effects for biosensing of glucose and galactose are designed and prepared by a one-pot chemical pre-synthesis/electropolymerization (CPSE) protocol. Dopamine (DA) as a reductant and a monomer, glucose oxidase (GOx) or galactose oxidase (GaOx) as the enzyme, and HAuCl4 or H2PtCl6 as an oxidant to trigger DA polymerization and the source of metallic nanoparticles, are mixed to yield polymeric bionanocomposites (PBNCs), which are then anchored on the electrode by electropolymerization of the remaining DA monomer. The prepared PBNC material has good biocompatibility, a highly uniform dispersion of the nanoparticles with a narrow size distribution, and high load/activity of the immobilized enzymes, as verified by transmission/scanning electron microscopy and electrochemical quartz crystal microbalance. The thus-prepared enzyme electrodes show a largely improved amperometric biosensing performance, e.g., a very high detection sensitivity (99 or 129,µA cm,2 mM,1 for glucose for Pt PBNCs on bare or platinized Au), a sub-micromolar limit of detection for glucose, and an excellent durability, in comparison with those based on conventional procedures. Also, the PBNC-based enzyme electrodes work well in the second-generation biosensing mode. The proposed one-pot CPSE protocol may be extended to the preparation of many other functionalized PBNCs for wide applications. [source] ChemInform Abstract: A One-Pot Preparation of Cyanamide from Dithiocarbamate Using Molecular Iodine.CHEMINFORM, Issue 9 2010Jayashree Nath 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: One-Pot Preparation of Fluorinated Propargylamines under Microwave Irradiation and Solvent-Free Conditions.CHEMINFORM, Issue 2 2009Wei-Qiong Du 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 Convenient One-Pot Preparation of N-Substituted 4-Phenylpiperidines.CHEMINFORM, Issue 21 2008Shigehiro Asano 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: Microwave-Assisted One-Pot Preparation of Tetrahydro-,-carboline Hydrochlorides under Solvent-Free Conditions.CHEMINFORM, Issue 17 2008Fei Liu 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] A Facile One-Pot Preparation of Alkyl Aminoaryl Sulfides for the Synthesis of GW7647 as an Agonist of Peroxisome Proliferator-Activated Receptor ,.CHEMINFORM, Issue 49 2006Jungyeob Ham 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] One-Pot Preparation of Esters from Carboxylic Acids Using the PPh3,CCl3CN System.CHEMINFORM, Issue 49 2003Doo Ok Jang Abstract For Abstract see ChemInform Abstract in Full Text. [source] Reaction of Halothane with sec-Butyllithium in the Presence of Zinc Halides , One-Pot Preparation of Chlorodifluorovinylzinc Reagent and Its Derivatization to ,-Chloro-,,,-difluorostyrene.CHEMINFORM, Issue 48 2003Masakazu Nishihara Abstract For Abstract see ChemInform Abstract in Full Text. [source] A New Protocol for the One-Pot Preparation of Highly Diastereomerically Enriched Secondary Amines and ,-Amino Esters Mediated by Lithium Perchlorate Solution in Diethyl Ether.CHEMINFORM, Issue 15 2003Mohammad R. Saidi No abstract is available for this article. [source] ChemInform Abstract: A One-Pot Preparation of 1-Benzyl-2,-deoxyinosine from Ionized 2,-Deoxyinosine.CHEMINFORM, Issue 20 2002Ki-Young Moon 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: Efficient One-Pot Preparation of Variously Substituted Thieno[2,3-b]thiophene.CHEMINFORM, Issue 7 2002Alain Comel 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: Practical Modifications and Applications of the Sharpless Asymmetric Aminohydroxylation in the One-Pot Preparation of Chiral Oxazolidin-2-ones.CHEMINFORM, Issue 1 2001Nancy S. Barta 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] Reactions of Polycyclic Ketones with Dimethoxycarbene; a Convenient Route for a ,One-Pot' Preparation of Some , -Hydroxycarboxylic Acid EstersHELVETICA CHIMICA ACTA, Issue 7 2007Jaros, aw Roma Abstract Polycyclic ,cage' ketones, such as pentacyclo[5.4.0.02,6.03,10.05,9]undecan-8-one (10), pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (11), and adamantan-2-one (16) were treated with the nucleophilic dimethoxycarbene (DMC; 1), which was generated thermally from 2,5-dihydro-2,2-dimethoxy-5,5-dimethyl-1,3,4-oxadiazole (4a) in boiling toluene. In this ,one-pot' procedure, the , -hydroxycarboxylic acid ester 12 or a corresponding derivative 15 or 17 was obtained (Schemes,4,7). Additionally, ,cage' thione 21 was treated with DMC under the same conditions yielding dimethoxythiirane 22 (Scheme,8). Subsequent hydrolysis or desulfurization (followed by hydrolysis on silica gel) of 22 gave , -mercaptocarboxylate 25 and the corresponding desulfurized ester 24, respectively. In all cases, the addition of DMC occurred stereoselectively, and the addition from the exo -face is postulated to explain the structures of the isolated products. [source] One-pot preparation of 3-miktoarm star terpolymers via click [3 + 2] reactionJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2007Ozcan Altintas Abstract The preparation of 3-miktoarm star terpolymers using nitroxide mediated radical polymerization (NMP), ring opening polymerization (ROP), and click reaction [3 + 2] are carried out by applying two types of one-pot technique. In the first one-pot technique, NMP of styrene (St), ROP of ,-caprolactone (,-CL), and [3 + 2] click reaction (between azide end-functionalized poly(ethylene glycol) (PEG-N3)/or azide end-functionalized poly(methyl methacrylate) (PMMA-N3) and alkyne) are carried out in the presence of 2-(hydroxymethyl)-2-methyl-3-oxo-3-(2-phenyl-2-(2,2,6,6-tetramethylpiperidin-1-yloxy)ethoxy) propyl pent-4-ynoate, 2, as an initiator for 48 h at 125 °C (one-pot/one-step). As a second technique, NMP of St and ROP of ,-CL were conducted using 2 as an initiator for 20 h at 125 °C, and subsequently PEG-N3 or azide end-functionalized poly(tert -butyl acrylate (PtBA-N3) was added to the polymerization mixture, followed by a click reaction [3 + 2] for 24 h at room temperature (one-pot/two-step). The 3-miktoarm star terpolymers, PEG-poly(,-caprolactone)(PCL)-PS, PtBA-PCL-PS and PMMA-PCL-PS, were recovered by a simple precipitation in methanol without further purification. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3588,3598, 2007 [source] N -(4-Nitrophenylsulfonyl)- and N -(Fluorenylmethoxycarbonyl)- N -ethyl Amino Acid Methyl Esters , A Practical ApproachEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 22 2010Emilia Lucia Belsito Abstract An efficient one-pot preparation of N -ethyl- N -4-nitrophenylsulfonyl (nosyl) amino acid methyl esters was accomplished by a simple N -ethylation reaction by using triethyloxonium tetrafluoroborate in the presence of N,N -diisopropylethylamine. The N -ethylated amino acid methyl esters are obtained with total retention of stereochemistry at the original chiral centers. To further broaden the scope of this methodology, the N -ethylated nosyl-protected compounds are easily converted in the more practical fluorenylmethyloxycarbonyl (Fmoc)-protected derivatives. The cleavage of methyl ester by using a mild and neutral method enables the preparation of N -ethyl amino acids that are building blocks suitable for introduction into a peptide chain. The methodology works well with both nosyl- and Fmoc-based solution-phase peptide synthesis. [source] A Novel Approach to the Practical Synthesis of Sulfides: An InBr3,Et3SiH Catalytic System Promoted the Direct Reductive Sulfidation of Acetals with DisulfidesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2009Norio Sakai Abstract We have demonstrated a facile and direct synthesis of sulfide derivatives using acetals and ketals, derived from aromatic/conjugated aldehydes and aromatic ketones, with disulfides and the InBr3,Et3SiH reducing system. We also succeeded in developing an unprecedented one-pot preparation of an aliphatic sulfide from a disulfide and an aliphatic acetal. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Diastereoselective Synthesis of -Hydroxy Sulfoxides: Enzymatic and Biomimetic ApproachesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2007Stefano Colonna Abstract Stereoselectivities of up to 98,% have been found in the enzymatic synthesis of ,-hydroxy sulfoxides catalyzed by cyclohexanone monooxygenase (CHMO). The diastereoselectivity of the "one-pot" preparation of the title compounds in the presence of bovine serum albumin has also been investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Highly Functionalised Enantiopure 4-Hydroxypyridine Derivatives by a Versatile Three-Component SynthesisADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2009Christian Eidamshaus Abstract The scope of a novel alkoxyallene-based pyridine synthesis was expanded to enantiopure carboxylic acids and nitriles as starting materials. The enantiomeric purity of the chiral ,-secondary carboxylic acids and nitriles was completely preserved during this reaction sequence thus allowing the one-pot preparation of a whole range of 4-hydroxypyridines or their 4-pyridinone tautomers in good yields. [source] A convenient preparation of 3-acetyl-5-methylisoxazoleJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2003Ronald R. Sauers Starting from 2,5-hexanedione (4), a one-pot preparation of 3-acetyl-5-methylisoxazole (1) is described. 3-Acetyl-5-methylisoxazole (1) is a useful compound for the preparation of 3-oxobutyronitrile (10) and for 3-vinyl-(5-methyl isoxazolyl) ketone (2). [source] | |||||||||||||