Search results for: Eric M. Villa

Items from 1 to 16 out of 16 results

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Synthesis, Characterization, and Structural Comparisons of the First Neodymium(III) Sulfite‐Acetate Crystal Structure

Jakob T. Dovgan, Matthew J. Polinski, Eric M. Villa

Zeitschrift für anorganische und allgemeine Chemie > 645 > 1 > 31 - 35

The first lanthanide sulfite compound with a secondary ligand, Nd(SO₃)(C₂H₃O₂), was hydrothermally synthesized and solved with single‐crystal X‐ray diffraction. In order to prevent the facile oxidation of the sulfite to sulfate, careful control of both pH and reaction temperature were required for successful synthesis of the title compound; even slight changes in conditions allow for the facile oxidation...

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A simple and efficient approach for the synthesis of 2-aminated quinazoline derivatives via metal free oxidative annulation

Amit N. Pandya, Eric M. Villa, E. Jeffrey North

Tetrahedron Letters > 2017 > 58 > 13 > 1276-1279

A simple and efficient approach for the synthesis of 2-aminoquinazoline derivatives in moderate to good yields. This reaction employs mild reaction conditions, is metal-free and utilizes readily available starting materials making it a more viable reaction for scale up synthesis and ligand diversity. Notably, this methodology allows for the synthesis of 2-aminoquinazolines using a free amine or cyclic...

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Stereoselective synthesis of exocyclic allenes by double hydride reduction of 3-alkynyl-2-cycloalkenones

Matthew A. Gubbels, Martin Hulce, John M. Kum, Andrew K. Urick, more

Tetrahedron > 2016 > 72 > 40 > 6052-6063

Exocyclic allene natural products and pharmaceutical agents are rare but interesting compounds: Fucoxanthin, grasshopper ketone, and analogues of prostacyclins, cephalosporins, antithrombic agents and sterol biosynthesis inhibitors are representative. Syntheses of exocyclic allenes commonly rely on extended conjugate additions to e.g., alk-2-en-4-ynones, syn S_N2′-like additions to alkynyl oxiranes,...

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Silver-mediated synthesis of indolizines via oxidative C–H functionalization and 5-endo-dig cyclization

Amit N. Pandya, James T. Fletcher, Eric M. Villa, Devendra K. Agrawal

Tetrahedron Letters > 2014 > 55 > 50 > 6922-6924

An efficient strategy for the synthesis of indolizines from readily available starting materials via oxidative C–H functionalization and 5-endo-dig cyclization in one step has been demonstrated. This protocol represents wide substrate scope, high functional group tolerance, and selectivity. The structure of the product was confirmed by X-ray crystallographic studies. Ag ₂ CO ₃ required...

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Topologically identical, but geometrically isomeric layers in hydrous α-, β-Rb[UO2(AsO3OH)(AsO2(OH)2)]·H2O and anhydrous Rb[UO2(AsO3OH)(AsO2(OH)2)]

Na Yu, Vladislav V. Klepov, Eric M. Villa, Dirk Bosbach, more

Journal of Solid State Chemistry > 2014 > 215 > Complete > 152-159

The hydrothermal reaction of uranyl nitrate with rubidium nitrate and arsenic (III) oxide results in the formation of polymorphic α- and β-Rb[UO ₂ (AsO ₃ OH)(AsO ₂ (OH) ₂ )]·H ₂ O (α-, β-RbUAs) and the anhydrous phase Rb[UO ₂ (AsO ₃ OH)(AsO ₂ (OH) ₂ )] (RbUAs). These phases were structurally, chemically and spectroscopically characterized...

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Oxoanion systems containing trivalent actinides

Matthew J. Polinski, Eric M. Villa, Thomas E. Albrecht-Schmitt

Coordination Chemistry Reviews > 2014 > 266-267 > Complete > 16-27

A review of trivalent actinide oxoanion compounds is presented. This work focuses on the systematics and periodic trends in the trivalent actinide series from Pu(III) to Cf(III). Three systems, are focused on: iodates, phosphites, and borates. In the first two series, the structure and bonding parallels that of lanthanides; whereas in the final series the chemistry of the actinides is distinct from...

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Facile Routes to Th^IV, U^IV, and Np^IV Phosphites and Phosphates

Eric M. Villa, Shuao Wang, Evgeny V. Alekseev, Wulf Depmeier, more

European Journal of Inorganic Chemistry > 2011 > 25 > 3749 - 3754

Three actinide(IV) phosphites and a Np^IV phosphate, An^IV(HPO₃)₂(H₂O)₂ (An = Th, U, Np) and Cs[Np(H_1.5PO₄)(PO₄)]₂, respectively, were synthesized using mild hydrothermal conditions. The first three phases are isotypic and were obtained using similar reaction conditions. Cs[Np(H_1.5PO₄)(PO₄)]₂ was synthesized using an analogous method to that of Np(HPO₃)₂(H₂O)₂. However, this fourth phase is quite different...

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¹⁷O NMR and Computational Study of a Tetrasiliconiobate Ion, [H_2+xSi₄Nb₁₆O₅₆]^(14−x)−

Rene L. Johnson, Eric M. Villa, C. A. Ohlin, James R. Rustad, more

Chemistry – A European Journal > 17 > 34 > 9359 - 9367

Rates of oxygen‐isotope exchange were measured in the tetrasiliconiobate ion [H_2+xSi₄Nb₁₆O₅₆]^(14−x)− to better understand how large oxide ions interact with water. The molecule has 19 nonequivalent oxygen sites and is sufficiently complex to evaluate hypotheses derived from our previous work on smaller clusters. We want to examine the extent to which individual oxygen atoms react independently with...

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Rates of Water Exchange for Two Cobalt(II) Heteropolyoxotungstate Compounds in Aqueous Solution

C. André Ohlin, Stephen J. Harley, J. Gregory McAlpin, Rosalie K. Hocking, more

Chemistry – A European Journal > 17 > 16 > 4408 - 4417

Polyoxometalate ions are used as ligands in water‐oxidation processes related to solar energy production. An important step in these reactions is the association and dissociation of water from the catalytic sites, the rates of which are unknown. Here we report the exchange rates of water ligated to Co^II atoms in two polyoxotungstate sandwich molecules using the ¹⁷O‐NMR‐based Swift–Connick method....

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Role of Anions and Reaction Conditions in the Preparation of Uranium(VI), Neptunium(VI), and Plutonium(VI) Borates

Shuao Wang, Eric M. Villa, Juan Diwu, Evgeny V. Alekseev, more

Inorganic Chemistry > 2011 > 50 > 6 > 2527 - 2533

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The first peroxotitanoniobate cluster – [N(CH3)4]10[Ti12Nb6O38(O2I)6]

C. André Ohlin, Eric M. Villa, James C. Fettinger, William H. Casey

Inorganica Chimica Acta > 2010 > 363 > 15 > 4405-4407

The synthesis and structure of the first discrete peroxotitanoniobate cluster, [N(CH3)4]10[Ti12Nb6O38(O2I)6], is described.

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Borate Accelerates Rates of Steady Oxygen‐Isotope Exchange for Polyoxoniobate Ions in Water

Eric M. Villa, C. André Ohlin, William H. Casey

Chemistry – A European Journal > 16 > 29 > 8631 - 8634

Borate: guilty and charged! The borate ion, and possibly carbonate, enhances rates of steady oxygen‐isotope exchanges at some, but not all, structural sites in polyoxometalate ions. Addition of an oxygen atom to an incoming neutral boric acid molecule (blue=boron) from a bridging oxygen atom on a decametalate ion is shown here.

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Oxygen-Isotope Exchange Rates for Three Isostructural Polyoxometalate Ions

Eric M. Villa, C. André Ohlin, William H. Casey

Journal of the American Chemical Society > 2010 > 132 > 14 > 5264 - 5272

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Kinetic study of the reaction of dimethyl carbonate with trialkylamines

Duane E. Weisshaar, Gary W. Earl, Eric M. Villa, Jessica L. (Paumen) Zierke, more

International Journal of Chemical Kinetics > 42 > 4 > 221 - 225

Quaternary ammonium compounds are produced worldwide in hundreds of millions of pound volume annually for a plethora of end‐uses from fabric‐care formulations to asphalt emulsifiers, typically from nongreen alkylating reagents. The kinetics of a reaction employing dimethyl carbonate (DMC) as a green alkylating agent was investigated using three trialkylamines (tributylamine, trihexylamine, and trioctylamine)...