Boys interrupted : sex between men in post-Franco Spanish cinema.

The synthesis and characterization of a stable, acyclic two-coordinate silylene, Si­(SAr^Me₆)₂ [Ar^Me₆ = C₆H₃-2,6­(C₆H₂-2,4,6-Me₃)₂], by reduction of Br₂Si­(SAr^Me₆)₂ with a magnesium­(I) reductant is described. It features a V-shaped silicon coordination with a S–Si–S angle of 90.52(2)° and an average Si–S distance of 2.158(3) Å. Although it reacts readily with an alkyl halide, it does not react with hydrogen under ambient conditions, probably as a result of the ca. 4.3 eV energy difference between the frontier silicon lone pair and 3p orbitals

The Role of Orbital Symmetries in Enforcing Ferromagnetic Ground State in Mixed Radical Dimers

One of the first steps in designing ferromagnetic (FM) molecular materials of p-block radicals is the suppression of covalent radical–radical interactions that stabilize a diamagnetic ground state. In this contribution, we demonstrate that FM coupling between p-block radicals can be achieved by constructing mixed dimers from different radicals with differing symmetries of their singly occupied molecular orbitals. The applicability of this approach is demonstrated by studying magnetic interactions in organic radical dimers built from different derivatives of the well-known phenalenyl radical. The calculated enthalpies of dimerization for different homo- and heterodimers show that the formation of a mixed dimer with FM coupling is favored compared to the formation of homodimers with antiferromagenetic (AFM) coupling. We argue that cocrystallization of radicals with specifically tuned morphologies of their singly occupied molecular orbitals is a feasible and promising approach in designing new organic magnetic materials

Pyrazolium- and 1,2-Cyclopentadiene-Based Ligands as σ-Donors: a Theoretical Study of Electronic Structure and Bonding

A high-level theoretical investigation of 1,2-cyclopentadiene (<b>4</b>) was performed using density functional theory and wave function methods. The results reveal that, in contrast to earlier assumptions, the ground state of this ephemeral “allene” is carbene-like with a small diradical component. Furthermore, the electronic structure and chemistry of <b>4</b> are found to parallel that of 1,2,4,6-cycloheptatetraene: both molecules possess a low-lying excited singlet state with a closed-shell carbenic structure, enabling rich coordination chemistry. Energy decomposition analyses conducted for currently unknown metal complexes of <b>4</b> as well as those involving stable carbenes based on the pyrazolium framework (aka “bent allenes” or remote N-heterocyclic carbenes) indicate that all investigated ligands form particularly strong metal–carbon bonds. Most notably, without exocyclic π-type substituents, <b>4</b> and pyrazolin-4-ylidenes are the strongest donor ligands examined, in large part because of the energy and shape of their highest occupied molecular orbital. As a whole, the current work opens a new chapter in the chemistry of 1,2-cyclopentadiene, which is hoped to spark renewed interest among experimentalists. In addition, results from the conducted bonding analyses underline that more emphasis should be placed on purely carbocyclic carbenes as unprecedented σ-donor strengths can be realized through this route

Computational Analysis of n→π* Back-Bonding in Metallylene–Isocyanide Complexes R₂MCNR′ (M = Si, Ge, Sn; R = <i>t</i>Bu, Ph; R′ = Me, <i>t</i>Bu, Ph)

A detailed computational investigation of orbital interactions in metal–carbon bonds of metallylene–isocyanide adducts of the type R₂MCNR′ (M = Si, Ge, Sn; R, R′ = alkyl, aryl) was performed using density functional theory and different methods based on energy decomposition analysis. Similar analyses have not been carried out before for metal complexes of isocyanides, even though the related carbonyl complexes have been under intense investigations throughout the years. The results of our work reveal that the relative importance of π-type back-bonding interactions in these systems increases in the sequence Sn < Ge ≪ Si, and in contrast to some earlier assumptions, the π-component cannot be neglected for any of the systems investigated. While the fundamental ligand properties of isocyanides are very similar to those of carbonyl, there are significant variations in the magnitudes of different effects observed. Most notably, on coordination to metals, both ligands can display positive or negative shifts in their characteristic stretching frequencies. However, because isocyanides are stronger σ donors, the metal-induced changes in the CN bonding framework are greater than those observed for carbonyl. Consequently, isocyanides readily exhibit positive CN stretching frequency shifts even in complexes where they function as π-acceptors, and the sign of these shifts is alone a poor indicator of the nature of the metal–carbon interaction. On the other hand, the relative π-character of the metal–carbon bond in metallylene–isocyanide adducts, as judged by the natural orbitals of chemical valence as well as by partitions of the orbital interaction energy, was shown to have a linear correlation with the shift in CN stretching frequency upon complex formation. The details of this correlation show that π-back-donation contributions to total orbital interaction energy need to exceed 100 kJ mol^–1 in order for the shift in the CN stretching frequency of metallylene–isocyanide adducts to be negative

The Nature of Transannular Interactions in E₄N₄ and E₈²⁺ (E = S, Se)

The electronic structures of tetrachalcogen tetranitrides, E₄N₄, and octachalcogen dications, E₈²⁺, and the nature of their <i>intramolecular</i> E···E interactions (E = S, Se) was studied with high-level theoretical methods. The results reveal that the singlet ground states of both systems have a surprisingly large correlation contribution which functions to weaken and therefore lengthen the cross-ring E–E bond. The observed correlation effects are primarily static in E₄N₄, whereas in E₈²⁺ the dynamic part largely governs the total correlation contribution. The presented description of bonding is the first that gives an all-inclusive picture of the origin of cross-ring interactions in E₄N₄ and E₈²⁺; not only does it succeed in reproducing all experimental structures but it also offers a solid explanation for the sporadic performance of different computational methods that has been reported in previous studies. Furthermore, the theoretical data demonstrate that E···E bonds in E₄N₄ and E₈²⁺ are unique and fundamentally different from, for example, dispersion that plays a major role in weak <i>intermolecular</i> chalcogen···chalcogen contacts

Heptacoordinated Molybdenum(VI) Complexes of Phenylenediamine Bis(phenolate): A Stable Molybdenum Amidophenoxide Radical

The syntheses, crystallographic structures, magnetic properties, and theoretical studies of two heptacoordinated molybdenum complexes with <i>N</i>,<i>N</i>′-bis­(3,5-di-<i>tert</i>-butyl-2-hydroxyphenyl)-1,2-phenylenediamine (H₄N₂O₂) are reported. A formally molybdenum­(VI) complex [Mo­(N₂O₂)­Cl₂(dmf)] (<b>1</b>) was synthesized by the reaction between [MoO₂Cl₂(dmf)₂] and H₄N₂O₂, whereas the other molybdenum­(VI) complex [Mo­(N₂O₂)­(HN₂O₂)] (<b>2</b>) was formed when [MoO₂(acac)₂] was used as a molybdenum source. Both complexes represent a rare case of the Mo^VI ion without any multiply bonded terminal ligands. In addition, molecular structures, magnetic measurements, ESR spectroscopy, and density functional theory calculations indicate that complex <b>2</b> is the first stable molybdenum­(VI) amidophenoxide radical

Heptacoordinated Molybdenum(VI) Complexes of Phenylenediamine Bis(phenolate): A Stable Molybdenum Amidophenoxide Radical

The syntheses, crystallographic structures, magnetic properties, and theoretical studies of two heptacoordinated molybdenum complexes with <i>N</i>,<i>N</i>′-bis­(3,5-di-<i>tert</i>-butyl-2-hydroxyphenyl)-1,2-phenylenediamine (H₄N₂O₂) are reported. A formally molybdenum­(VI) complex [Mo­(N₂O₂)­Cl₂(dmf)] (<b>1</b>) was synthesized by the reaction between [MoO₂Cl₂(dmf)₂] and H₄N₂O₂, whereas the other molybdenum­(VI) complex [Mo­(N₂O₂)­(HN₂O₂)] (<b>2</b>) was formed when [MoO₂(acac)₂] was used as a molybdenum source. Both complexes represent a rare case of the Mo^VI ion without any multiply bonded terminal ligands. In addition, molecular structures, magnetic measurements, ESR spectroscopy, and density functional theory calculations indicate that complex <b>2</b> is the first stable molybdenum­(VI) amidophenoxide radical

Griffith v. Gonzales-Alpizar, 132 Nev. Adv. Op. 38 (May 26, 2016)

The Court held that under NRS 125.040, a district court has the power to grant attorney fees pendente lite for appeals in divorce actions

Mechanistic Studies on the Metal-Free Activation of Dihydrogen by Antiaromatic Pentarylboroles

The perfluoro- and perprotiopentaphenylboroles <b>1</b> and <b>2</b> react with dihydrogen to effect H–H bond cleavage and formation of boracyclopentene products. The mechanism of this reaction has been studied experimentally through evaluation of the kinetic properties of the slower reaction between <b>2</b> and H₂. The reaction is first-order in both [borole] and [H₂] with activation parameters of Δ<i>H</i>^⧧ = 34(8) kJ/mol and Δ<i>S</i>^⧧ = −146(25) J mol^–1 K^–1. A minimal kinetic isotope effect of 1.10(5) was observed, suggesting an asynchronous geometry for H–H cleavage in the rate-limiting transition state. To explain the stereochemistry of the observed products, a ring-opening/ring-closing mechanism is proposed and supported by the separate synthesis of a proposed intermediate and its observed conversion to product. Furthermore, extensive DFT mapping of the reaction mechanism supports the plausibility of this proposal. The study illustrates a new mechanism for the activation of H₂ by a strong main group Lewis acid in the absence of an external base, a process driven in part by the antiaromaticity of the borole rings in <b>1</b> and <b>2</b>

Isolation of a Stable, Acyclic, Two-Coordinate Silylene

The synthesis and characterization of a stable, acyclic two-coordinate silylene, Si­(SAr^Me₆)₂ [Ar^Me₆ = C₆H₃-2,6­(C₆H₂-2,4,6-Me₃)₂], by reduction of Br₂Si­(SAr^Me₆)₂ with a magnesium­(I) reductant is described. It features a V-shaped silicon coordination with a S–Si–S angle of 90.52(2)° and an average Si–S distance of 2.158(3) Å. Although it reacts readily with an alkyl halide, it does not react with hydrogen under ambient conditions, probably as a result of the ca. 4.3 eV energy difference between the frontier silicon lone pair and 3p orbitals