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Diamine
Kinds of Diamine Terms modified by Diamine Selected AbstractsDetermining the Vapor Pressures of Diacetone Diperoxide (DADP) and Hexamethylene Triperoxide Diamine (HMTD)PROPELLANTS, EXPLOSIVES, PYROTECHNICS, Issue 6 2009Jimmie Abstract The vapor signature of diacetone diperoxide (DADP) and hexamethylene triperoxide diamine (HMTD) were examined by a gas chromatography (GC) headspace technique over the range of 15 to 55,°C. Parallel experiments were conducted to redetermine the vapor pressures of 2,4,6-trinitrotoluene (TNT) and triacetone triperoxide (TATP). The TNT and TATP vapor pressures were in agreement with the previously reported results. Vapor pressure of DADP was determined to be 17.7,Pa at 25,°C, which is approximately 2.6 times higher than TATP at the same temperature. The Clapeyron equation, relating vapor pressure and temperature, was LnP (Pa)=35.9,9845.1/T (K) for DADP. Heat of sublimation, calculated from the slope of the line for the Clapeyron equation, was 81.9,kJ mole,1. HMTD vapor pressure was not determined due to reduced thermal stability resulting in vapor phase decomposition products. [source] Catalytic Asymmetric Mannich-Type Reactions Activated by ZnF2 Chiral Diamine in Aqueous Media.CHEMINFORM, Issue 16 2006Tomoaki Hamada 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 Modular Design of Ruthenium Catalysts with Diamine and BINOL-Derived Phosphinite Ligands that Are Enantiomerically-Matched for the Effective Asymmetric Transfer Hydrogenation of Simple Ketones.CHEMINFORM, Issue 43 2005Rongwei Guo Abstract For Abstract see ChemInform Abstract in Full Text. [source] Factors Influencing the Course of the Macrocyclization of ,,, -Diamines with Esters of ,,, -Dicarboxylic AcidsHELVETICA CHIMICA ACTA, Issue 1 2004Dorota Gryko The efficient synthesis of eight new macrocyclic amides (lactams) via reaction of diesters with diamines under normal dilution conditions is described. The role of intermolecular H-bond formation and steric hindrance is discussed based on 1H- and 15N-NMR studies of appropriate model compounds. Principles for the optimal choice of esters that can be efficiently transformed into diamides have been developed. [source] Methoxycarbonylation of Aliphatic Diamines with Dimethyl Carbonate Promoted by in situ Generated Hydroxide Ion: A Mechanistic ConsiderationADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Dae Won Kim Abstract The methoxycarbonylation reactions of aliphatic diamines with dimethyl carbonate are accelerated greatly in the presence of water. Theoretical investigations on the mechanistic aspects of the methoxycarbonylation of 1,6-hexanediamine strongly suggest that the hydroxide ion, generated in situ from the interaction of 1,6-hexanediamine with water, is an active catalytic species and plays a pivotal role in the rate-determining hydrogen abstraction step from the amino group. [source] Synthesis of Selectively Mono-N-Arylated Aliphatic Diamines via Iridium-Catalyzed Amine AlkylationADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17 2009Benoît Blank Abstract A highly selective phosphorus/nitrogen (P,N) ligand-based iridium catalyst system efficiently catalyzes the reaction of arylamines with unprotected amino alcohols, yielding N-arylated aliphatic diamines in yields of up to 93%. The reaction can be performed with a wide variety of branched and linear amino alcohols in combination with various aminopyridines or substituted anilines. [source] Domino Reaction of Acyclic ,,,-Dialkenoylketene S,S -Acetals and Diamines: Efficient Synthesis of Tetracyclic Thieno[2,3- b]thiopyran-Fused Imidazo[1,2- a]pyridine/Pyrido[1,2- a]pyrimidinesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14 2006Fushun Liang Abstract A series of unusual fused tetraheterocyclic compounds 3, consisting of a thiopyran (ring A), a thiophene (ring B), a pyridine (ring C), and an imidazole or a pyrimidine (ring D) core, with a bridgehead nitrogen and an angular methyl group, were successfully synthesized by a catalyst-free, one-pot, two-component domino reaction of 4-(4-methyl-1,3-dithiol-2-ylidene)-1,7-bis(aryl/heteroaryl)hepta-1,6-diene-3,5-dione 2 and diamines. In this reaction, up to five new bonds were formed accompanied by the CS bond cleavage of the 1,3-dithiole ring of 2, with water as the only by-product. [source] Synthesis and Properties of 6FDA-MDA Copolyimide Membranes: Effects of Diamines and Dianhydrides on Gas Separation and Pervaporation PropertiesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 24 2007Shude Xiao Abstract 6FDA-MDA-based polyimides were synthesized from a one-step polycondensation of 6FDA and MDA with other diamines and dianhydrides. The polyimides were characterized by GPC, FT-IR and NMR, and dense membranes were prepared from their solutions for gas separation and pervaporation. Gas separation and pervaporation properties were investigated using the linear moiety contribution method. The moiety contribution factors were used to analyze the effects of the dianhydride and diamine monomers on gas permselectivity and pervaporation permeation flux. It was shown that the steric effects and flexibility of the monomers and the interactions between the membrane and the penetrants accounted for the differences in separation properties. [source] Flexible Hybrid Semiconductors with Low Thermal Conductivity: The Role of Organic Diamines,ANGEWANDTE CHEMIE, Issue 42 2009Xiaoying Huang Dr. Flexible Leiter: Einzigartig sind die hier vorgestellten Halbleiterkristalle aus einer organisch-anorganischen Hybridverbindung wegen ihrer Flexibilität und niedrigen thermischen Leitfähigkeit. Die Hybride bestehen aus ZnTe-Schichten, die durch unterschiedliche Diamine verknüpft sind (im Bild ist ein Beispiel zu sehen; C,graue, N,blaue, Te,rote, Zn,hellblaue Kugeln). [source] ChemInform Abstract: Selective Iridium-Catalyzed Alkylation of (Hetero)Aromatic Amines and Diamines with Alcohols under Mild Reaction Conditions.CHEMINFORM, Issue 32 2009Benoit 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: Steric Modulation of Chiral Biaryl Diamines via Pd-Catalyzed Directed C,H Arylation.CHEMINFORM, Issue 31 2009Christopher C. Scarborough 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: The Direct Synthesis of Unsymmetrical Vicinal Diamines from Terminal Alkynes: A Tandem Sequential Approach for the Synthesis of Imidazolidinones.CHEMINFORM, Issue 20 2009Alison V. Lee 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 Reaction of Tanshinones with Diamines.CHEMINFORM, Issue 3 2007Lin-Kun An 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] Preparation of Diamines of Adamantane and Diamantane from the Diazides.CHEMINFORM, Issue 45 2006Matthew C. Davis 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] Nickel(0)/N-Heterocyclic Carbene Complexes Catalyzed Arylation of Aromatic Diamines.CHEMINFORM, Issue 29 2006Sebastien Kuhl 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] Organolithium-Mediated Conversion of ,-Functionalized Aziridines into Alkynyl Amino Alcohols and Diamines.CHEMINFORM, Issue 13 2006Jianhui Huang 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] Synthesis of Chiral Vicinal Diamines by Highly Diastereoselective Three-Component Phenolic Mannich Reaction: Temperature-Dependent Stereodivergency.CHEMINFORM, Issue 37 2005Christophe Rondot No abstract is available for this article. [source] Microwave-Induced Clay-Catalyzed Ring Opening of N-Tosylaziridines: A Green Approach to Achiral and Chiral Diamines.CHEMINFORM, Issue 28 2005Upender K. Nadir Abstract For Abstract see ChemInform Abstract in Full Text. [source] A Convenient Preparation of Tetrahydrofuran-Based Diamines.CHEMINFORM, Issue 42 2004Gaifa Lai Abstract For Abstract see ChemInform Abstract in Full Text. [source] Practical Asymmetric Synthesis of Vicinal Diamines Through the Catalytic Highly Enantioselective Alkylation of Glycine Amide Derivatives.CHEMINFORM, Issue 12 2004Takashi Ooi Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis of N,N,-Alkylated Tetrahydroquinoxalines by the Reaction of 4-Bromo-5-nitrophthalonitrile with Secondary Diamines.CHEMINFORM, Issue 4 2003I. G. Abramov Abstract For Abstract see ChemInform Abstract in Full Text. [source] Nickel-Catalyzed Selective N-Arylation or N,N,-Diarylation of Secondary Diamines.CHEMINFORM, Issue 52 2002Eric Brenner Abstract For Abstract see ChemInform Abstract in Full Text. [source] Catalytic Oxidation Carbonylation of Primary and Secondary Diamines to Cyclic Ureas.CHEMINFORM, Issue 47 2002Optimization, Substituent Studies. Abstract For Abstract see ChemInform Abstract in Full Text. [source] Efficient Synthesis of Medium-Sized Cyclic Ether Diamines.CHEMINFORM, Issue 35 2002Sang Hyup Lee No abstract is available for this article. [source] ChemInform Abstract: Catalytic Asymmetric Borane Reduction of Prochiral Ketones by the Use of Diazaborolidine Catalysts Prepared from Chiral ,-Diamines.CHEMINFORM, Issue 14 2001Shinsuke Sato 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: Rapid Access to Enantiopure Bicyclic Diamines via aza-Diels,Alder Reaction of Iminoamides.CHEMINFORM, Issue 6 2001Stefan A. Modin 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] Selective Iridium-Catalyzed Alkylation of (Hetero)Aromatic Amines and Diamines with Alcohols under Mild Reaction ConditionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 15 2009Benoît Blank Abstract Selective amine alkylation: A P,N-ligand-stabilized iridium complex has been used as an efficient catalyst for the alkylation of (hetero)aromatic amines with alcohols at mild reaction temperatures and catalyst loadings as low as 0.1,mol,% Ir (see scheme). The excellent selectivity of the catalyst for monoalkylation of the amine function has also been exploited for the N,N,-dialkylation of diamines in both symmetric and nonsymmetric fashions. A P,N-ligand-coordinated iridium complex has been employed as an efficient catalyst for the selective monoalkylation of (hetero)aromatic amines with alcohols. A significant improvement of this alkylation method has been achieved, such that it can be performed at a temperature of 70,°C and with catalyst loadings as low as 0.1,mol,% Ir, while still affording excellent yields of secondary amines. Furthermore, the high selectivity of this catalyst for the monoalkylation of aromatic amino functions has been successfully exploited for the alkylation of diamines in both symmetric and nonsymmetric fashions, providing a novel and very efficient synthetic tool for the preparation of N,N,-dialkylated aromatic diamines. Ein P,N-Ligand-koordinierter Iridiumkomplex wird als ein effizienter Katalysator für die selektive Monoalkylierung von (hetero)aromatischen Aminen mit Alkoholen beschrieben. Eine signifikante Verbesserung dieser Alkylierungsmethode wurde erreicht. Bei Temperaturen von 70,°C und mit Katalysatorbeladungen von bis zu 0.1,mol,% Ir konnten exzellente Ausbeuten für sekundäre Amine erhalten werden. Weiterhin konnte die hohe Selektivität des Katalysators hinsichtlich der Monoalkylierung von aromatischen Aminogruppen genutzt werden, um Diamine symmetrisch und unsymmetrisch zu alkylieren. Damit steht ein neues sehr effizientes Synthesewerkzeug zur Darstellung von N,N, -alkylierten aromatischen Diaminen zur Verfügung. [source] Synthesis and Biological Studies of N -Alkylated Cyclic DiaminesCHEMISTRY & BIODIVERSITY, Issue 1 2007Xiao-Qin Xiong Abstract Several alkyl-substituted mesocyclic diamines were synthesized, and their interaction with DNA were studied by melting-temperature measurements and the ethidium bromide (EB)-fluorescence competitive method. The supercoiled DNA hydrolytic cleavage by 1,4-dioctyl-1,4-diazepan-6-ol (4) was supported by the evidence from free-radical quenching and T4-ligase ligation. Preliminary pharmacological tests showed that only 1,4-dioctyl-1,4-diazepan-6-ol (4) had antitumor activity against HeLa cell lines in vitro. [source] Self-Assembly of Two-Component Gels: Stoichiometric Control and Component SelectionCHEMISTRY - A EUROPEAN JOURNAL, Issue 2 2009Andrew Abstract Two-component systems capable of self-assembling into soft gel-phase materials are of considerable interest due to their tunability and versatility. This paper investigates two-component gels based on a combination of a L -lysine-based dendron and a rigid diamine spacer (1,4-diaminobenzene or 1,4-diaminocyclohexane). The networked gelator was investigated using thermal measurements, circular dichroism, NMR spectroscopy and small angle neutron scattering (SANS) giving insight into the macroscopic properties, nanostructure and molecular-scale organisation. Surprisingly, all of these techniques confirmed that irrespective of the molar ratio of the components employed, the "solid-like" gel network always consisted of a 1:1 mixture of dendron/diamine. Additionally, the gel network was able to tolerate a significant excess of diamine in the "liquid-like" phase before being disrupted. In the light of this observation, we investigated the ability of the gel network structure to evolve from mixtures of different aromatic diamines present in excess. We found that these two-component gels assembled in a component-selective manner, with the dendron preferentially recognising 1,4 - diaminobenzene (>70,%), when similar competitor diamines (1,2- and 1,3-diaminobenzene) are present. Furthermore, NMR relaxation measurements demonstrated that the gel based on 1,4-diaminobenzene was better able to form a selective ternary complex with pyrene than the gel based on 1,4-diaminocyclohexane, indicative of controlled and selective ,,, interactions within a three-component assembly. As such, the results in this paper demonstrate how component selection processes in two-component gel systems can control hierarchical self-assembly. [source] Concomitant contact allergy to the resins, reactive diluents and hardener of a bisphenol A/F-based epoxy resin in subway construction workersCONTACT DERMATITIS, Issue 3 2006Chia-Yu Chu An outbreak of suspected contact dermatitis among subway construction workers was suspected to be due to a new bisphenol A/F-based epoxy resin system (ERS). The construction workers used ERSs during the insertion of iron bars into concrete walls. The objective of the study was to determine the components (if any) of the ERS responsible for the contact allergy. Patch testing was performed on 20 of the 22 construction workers who had had contact with the ERS, and to the various subcomponents of component A on 5 of the 7 who reacted to this component. 9 patients (9/22, 40.9%) had clinical symptoms and signs of suspected contact dermatitis at presentation. 7 of these 9, but none of the 11 asymptomatic individuals, were positive to component A, while all were negative to component B. Of the 5 cases receiving further patch testing, all reacted to m -xylylene diamine, 4 to 1,6-hexanediol diglycidyl ether, 3 to epoxy resins of the bisphenol F-type and trimethylolpropane triglycidyl ether 0.25% petrolatum, and only 1 to epoxy resins of the bisphenol A-type. Contact allergy to ERSs may involve hardeners and diluents as well as resins, and patch testing for reaction to all components should be performed. [source] | ||||||||||||||||||||||