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Liquid Ammonia (liquid + ammonia)
Selected AbstractsChemInform Abstract: Crystal Structures of Ag2ZrF6×8NH3 and Ag2HfF6×8NH3 and Their Synthesis by the "Reactive Fluoride Route" in Liquid Ammonia.CHEMINFORM, Issue 39 2008Weizhe Meng 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: Liquid Ammonia Mediated Metathesis: Synthesis of Binary Metal Chalcogenides and Pnictides.CHEMINFORM, Issue 9 2002G. A. Shaw 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 halo- and dihaloadamantanes with nitromethane anions by the SRN1 mechanismJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 8 2003Ana N. Santiago Abstract The reactions of 1-bromo-, 2-bromo-, 1,3-dibromo- and 1,4-dibromoadamantane with ,CH2NO2 anions were studied in DMSO and in liquid ammonia. The photostimulated reaction of 1-haloadamantane (1-AdX, X,=,Br, I) or 2-AdBr with ,CH2NO2 anions gave good yields of the substitution product 1-AdCH2NO2 and 2-AdCH2NO2, respectively, in the presence of the enolate anions of acetone (entrainment conditions). On the other hand, 1-adamantanol was the main product of the reaction performed in DMSO without irradiation, but not in liquid ammonia. 1,3-Dibromo and 1,4-dibromoadamantane reacted with ,CH2NO2 anions under irradiation in the presence of the enolate anions of acetone. The first compound gave the disubstitution product 11, and the second the monobromo-substitution products 15 and 16, together with the disubstitution product 17. Compounds 15 and 16 were shown to be intermediates in the formation of 17. Copyright © 2003 John Wiley & Sons, Ltd. [source] EuI2, a low-temperature europium(II) iodide phaseACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Michael Krings Light-yellow europium(II) diiodide, prepared by the low-temperature reaction of europium and ammonium iodide in liquid ammonia at 200,K and characterized by high-resolution X-ray powder diffraction, represents a new phase for EuI2 that adopts an orthorhombic Pnma structure with all three atoms lying on 4c positions (.m.). It is isotypic with SrI2(IV). Temperature-dependent X-ray measurements performed to investigate the thermal stability of the new phase show that it decomposes irreversibly to amorphous material around 673,K. Total-energy density-functional calculations using the generalized gradient approximation suggest this to be the ground-state structure of EuI2. [source] Three-step synthesis of arylpolyboronic acids from phenols via organotin compoundsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 8 2007Pablo M. Fidelibus Abstract In this paper we describe a three-step synthesis of aryldi- and triboronic acids starting from phenols. Several substituted phenols (I) were converted into the corresponding aryldiethylphosphates (II) in good to excellent yields. The latter, on reaction with sodium trimethylstannide in liquid ammonia, under irradiation, afforded the aryl- and heteroarylpoly(trimethylstannyl) derivatives in 65,90% yield. The third step is the reaction of the organotin compounds with borane in THF, which leads to the corresponding arylpolyboronic acids in around 80% yield. In order to confirm their structure, some of the diboronic acids were converted into the corresponding pinacol esters. The results obtained in a study on the synthesis of various terphenyls through double and triple Suzuki couplings catalyzed by palladium acetate between the obtained arylpolyboronic acids and various aryl halides are also reported. These reactions proceeded with an average 65% yield, and also enabled us to confirm the structures of some of the diboronic acids. The structure of the new compounds was determined by 1H, 13C and 119Sn NMR spectroscopy, mass spectrometry and IR spectroscopy. Copyright © 2007 John Wiley & Sons, Ltd. [source] The Subtle Influence of Binary versus Homoatomic Zintl Ions: The Phenyl-Ligated Trimetallic Cage [Sn2Sb5(ZnPh)2]3,CHEMISTRY - A EUROPEAN JOURNAL, Issue 47 2009Felicitas Lips Dipl.-Chem. Zintlating stuff! The first binary Sn/Sb Zintl anions produced by solution techniques were obtained in [K([2.2.2]crypt)]2[Sn2Sb2],en (en=ethylenediamine) and [K6(NH3)9][Sn3Sb4] upon extraction of K8SnSb4 by en or liquid ammonia. Addition of ZnPh2 to the en/[2.2.2]crypt extract resulted in the formation of a heterotrimetallic complex in [K([2.2.2]crypt)]3[Sn2Sb5(ZnPh)2],en,0.5tol (see scheme). [source] Segregation of Inorganic Ions at Surfaces of Polar Nonaqueous LiquidsCHEMPHYSCHEM, Issue 10 2007Lukasz Cwiklik Dr. Abstract We present a short review of recent computational and experimental studies on surfaces of solutions of inorganic salts in polar nonaqueous solvents. These investigations complement our knowledge of aqueous interfaces and show that liquids such as formamide, liquid ammonia, and ethylene glycol can also surface-segregate large polarizable anions like iodide, albeit less efficiently than water. For liquids whose surfaces are covered with hydrophobic groups (e.g. methanol), the surface-ion effect all but disappears. Based on the present data a general picture of inorganic-ion solvation at the solution,vapor interface of polar liquids is outlined. [source] Transfection of Cells Mediated by Biodegradable Polymer Materials with Surface-Bound PolyethyleneimineBIOTECHNOLOGY PROGRESS, Issue 2 2000Ji Zheng Poly(,-CBZ- L -lysine) can be mixed with biodegradable polymers such as poly(D,L -lactic- co -glycolic acid) or poly(L -lactic acid) and formed into films, foams, or microspheres. Surface amino groups may then be deprotected with acid or lithium/liquid ammonia. The amino groups serve as a method to modify the surface by attachment of other molecules. In the present experiments, we show that these polymer materials, as films or foams, may be surface modified by the attachment of polyethyleneimine (PEI). Plasmid DNA attached to the PEI can transfect cells plated on the surface over several days. Covalent atachment of PEI was required for transfection to be efficient. PEI was also attached to surface-bound collagen on cell culture plates and was shown to mediate transfection. [source] | ||||||||||