Gas phase observation and microwave spectroscopic characterization of formic sulfuric anhydride

Science ◽  
2015 ◽  
Vol 349 (6243) ◽  
pp. 58-61 ◽  
Author(s):  
Rebecca B. Mackenzie ◽  
Christopher T. Dewberry ◽  
Kenneth R. Leopold
Keyword(s):  
Gas Phase ◽  
Sulfur Trioxide ◽  
Density Functional ◽  
Supersonic Jet ◽  
Cycloaddition Reaction ◽  
Spectroscopic Characterization ◽  
Microwave Spectroscopy ◽  
Sulfuric Anhydride ◽  
Functional Theory

We report the observation of a covalently bound species, formic sulfuric anhydride (FSA), that is produced from formic acid and sulfur trioxide under supersonic jet conditions. FSA has been structurally characterized by means of microwave spectroscopy and further investigated by using density functional theory and ab initio calculations. Theory indicates that a π2 + π2 + σ2 cycloaddition reaction between SO3 and HCOOH is a plausible pathway to FSA formation and that such a mechanism would be effectively barrierless. We speculate on the possible role that FSA may play in the Earth’s atmosphere.

Phosphoramides bearing isoxazole derivative: spectroscopic and structural characterization, study of hydrogen-bonding interactions and two lanthanide complexes (LnIII= Ce and Eu)

2015 ◽  
Vol 71 (2) ◽  
pp. 176-185 ◽  
Author(s):  
Khodayar Gholivand ◽  
Foroogh Molaei ◽  
Mahdieh Hosseini
Keyword(s):  
Lanthanide Complexes ◽  
Density Functional ◽  
Spectroscopic Characterization ◽  
Crystalline Lattice ◽  
Ligand Interaction ◽  
Functional Theory ◽  
X Ray Crystallography ◽  
Isoxazole Derivative ◽  
Characterization Study

In this study, the synthesis and spectroscopic characterization of new phosphoramides based on 3-amino-5-methylisoxazole with the formulaR2P(O)[NH–C4H4NO],R= C6H5O (1), C6H5(2),RP(O)[NH—C4H4NO]2,R= C6H5O (3), CH3—C6H4O (4), C6H5NH (5), (C6H5)ClP(O)[NH–C4H4NO] (6) and two lanthanide complexes [Ln(2)2(NO3)3(EtOH)]·EtOH, LnIII= Ce (7) and Eu (8), have been reported. The structural study of (3) shows the presence of two conformers (crystallographically independent molecules) in the crystalline lattice, caused by different orientations of the phenyl and isoxazole rings. For (3), the intermolecular interactions have been studied by Hirshfeld surface analysis and fingerprint plots. Furthermore, the electronic and energy aspects of hydrogen bonds between molecules of (3) have been explored by density functional theory (DFT) calculations. X-ray crystallography of complexes (7) and (8) reveals that two phosphoramide ligands take part in coordination to the metal, one as monodentate from Ophosphoryl, and the other one as chelate through Ophosphoryland Nring. The complexes are also composed of two conformers in the solid-state structure. Quantum theory of atoms in molecules (QTAIM) analysis discloses the electrostatic nature of the Ln–ligand interaction.

Vibrational spectroscopic characterization of arylisoquinolines by means of Raman spectroscopy and density functional theory calculations

2017 ◽  
Vol 19 (44) ◽  
pp. 29918-29926 ◽  
Author(s):  
Robert Domes ◽  
Christian Domes ◽  
Christian R. Albert ◽  
Gerhard Bringmann ◽  
Jürgen Popp ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Density Functional ◽  
Resonance Raman Spectroscopy ◽  
Density Functional Theory Calculations ◽  
Spectroscopic Characterization ◽  
Functional Theory ◽  
Antimalarial Agents ◽  
Uv Resonance Raman Spectroscopy ◽  
Deep Uv

Seven new AIQ antimalarial agents were investigated using FT-NIR and deep-UV resonance Raman spectroscopy.

scholarly journals Theoretical Study of the [4+2] Cycloaddition Reaction of Trifluoroethylene with Five-membered Chalcogens Heterocyclic Compounds

2019 ◽  
Vol 7 (2) ◽  
pp. 69-77
Author(s):  
Haydar A. Mohammad-Salim ◽  
Hassan H. Abdallah
Keyword(s):  
Gas Phase ◽  
Density Functional ◽  
Theoretical Study ◽  
Cycloaddition Reaction ◽  
Branching Ratio ◽  
Basis Set ◽  
Stationary Points ◽  
Functional Theory ◽  
Highest Occupied Molecular Orbital ◽  
Synthesis Reactions

[4+2] cycloaddition reaction has enormous significant in organic chemistry synthesis reactions and yet remains unexplored for the synthesis of fluorine-containing compounds. A density functional theory study of the stereo- and regioselectivity of the [4+2] cycloaddition reaction of trifluoroethylene with furan, thiophene, and selenophene was carried out in the gas phase. The B3LYP functional is used throughout in combination with 6-31G(d) basis set. The analysis of stationary points and the energetic parameters indicates that the reaction mechanism is concerted and confirms that the exo-adducts are thermodynamically and kinetically more favored than endo-adducts. The calculated branching ratio indicates that the exo-adducts have the higher percent yield than endoadducts and the yield of endo-adducts is increased only slightly on proceeding from furan, through thiophene, and onto selenophene. The analysis of the frontier molecular highest occupied molecular orbital (MO) and lowest unoccupied MO orbitals indicates that the exo-adducts are more stable due to their higher energy gab. The reaction energies were compared to the MP2/6-31G(d) and CCSD(T)/6-31G(d) calculations.

scholarly journals Synthesis and Electrochemical and Spectroscopic Characterization of 4,7-diamino-1,10-phenanthrolines and Their Precursors

Molecules ◽  
2019 ◽  
Vol 24 (22) ◽  
pp. 4102 ◽  
Author(s):  
Nycz ◽  
Wantulok ◽  
Sokolova ◽  
Pajchel ◽  
Stankevič ◽  
...  
Keyword(s):  
Density Functional ◽  
Spectroscopic Characterization ◽  
Frontier Molecular Orbitals ◽  
X Ray Diffraction ◽  
Nucleophilic Substitutions ◽  
Functional Theory ◽  
X Ray ◽  
Homo And Lumo ◽  
Cp Mas Nmr

New approaches to the synthesis of 4,7-dichloro-1,10-phenanthrolines and their corresponding 9H-carbazol-9-yl-, 10H-phenothiazin-10-yl- and pyrrolidin-1-yl derivatives were developed. Their properties have been characterized by a combination of several techniques: MS, HRMS, GC-MS, electronic absorption spectroscopy and multinuclear NMR in both solution and solid state including 15N CP/MAS NMR. The structures of 5-fluoro-2,9-dimethyl-4,7-di(pyrrolidin-1-yl)-1,10-phenanthroline (5d), 4,7-di(9H-carbazol-9-yl)-9-oxo-9,10-dihydro-1,10-phenanthroline-5-carbonitrile (6a) and 4,7-di(10H-phenothiazin-10-yl)-1,10-phenanthroline-5-carbonitrile (6b) were determined by single-crystal X-ray diffraction measurements. The nucleophilic substitutions of hydrogen followed by oxidation produced compounds 6a and 6b. The electrochemical properties of selected 1,10-phenanthrolines were investigated using cyclic voltammetry and compared with commercially available reference 1,10-phenanthrolin-5-amine (5l). The spatial distribution of frontier molecular orbitals of the selected compounds has been calculated by density functional theory (DFT). It was shown that potentials of reduction and oxidation were in consistence with the level of HOMO and LUMO energies.

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