Regio- and Stereochemical Aspects of the Palladium-Catalyzed Desilylation-Arylation of Substituted Vinylsilanes

The palladium-catalyzed desilylation-arylation of substituted vinylsilanes by p-iodoanisole in the presence of bidentate phosphine ligands is described. Apart from enhancing the rate of the reaction considerably, heteroatom-based functional groups in the vinylsilane moiety have a profound influence on the regiochemistry. A catalytic cycle for the chelation-controlled desilylation-arylation reaction involving five- and six-membered chelate rings is proposed.     

Mononuclear Thiolatecobalt Carbonyls

A Partial Statistically Incorporation of Ca²⁺ into the Ba₆Nd₂Al₄O₁₅-Type: Ba₅CaLa₂Fe₄O₁₅ Using high temperature reactions we succeeded in incorporating Ca²⁺ into the Ba₆Nd₂Al₄O₁₅ type. Single crystal X-ray methods reveal a partly ordered alkaline earth distribution. Ba²⁺ and Ca²⁺ occupy face connected MO₆-octahedra as well as a further point position together with La³⁺ ions (space group C−P6₃mc; a = 11.770; c = 7.039 Å; Z = 2).     

Synthesis,characterization and biological activity of bis(3‐Aryl‐1‐hexahydropyrimidinyl)methanes. Novel heterocyclic polyamine derivatives

A method is described for the synthesis of bis(3‐aryl‐1‐hexahydropyrimidinyl)methanes 1, by condensation of N‐aryl‐1,3‐propanediarnines 2 with formaldehyde. The reaction mechanism involves N‐arylhexahydropyrimidines 3 as intermediates. Such compounds can also be prepared efficiently by a methylene exchange reaction between bis‐hexahydropyrimidines 1 and the corresponding diamines 2. The antimicrobial activity of compounds 1 was evaluated by the disk diffusion method and some of them showed moderate to good growth inhibition activity.     

Synthesis of C-2 Unsubstituted Furanonaphthoquinones

Four C-2 unsubstituted naphtho[2,3-b]furan-4,9-quinones were prepared via the corresponding phthalides obtained by directed ortho-metalation-based route.     

A Large Deviations Principle Related to the Strong Arc-Sine Law

We show a large deviations principle for the family of random variables when t+, where B=(B _u ,u0) is a standard linear Brownian motion.     

Neural markers of a greater female responsiveness to social stimuli

Background  

There is fMRI evidence that women are neurally predisposed to process infant laughter and crying. Other findings show that women might be more empathic and sensitive than men to emotional facial expressions. However, no gender difference in the brain responses to persons and unanimated scenes has hitherto been demonstrated.     

Global s-solvability and global s-hypoellipticity for certain perturbations of zero order of systems of constant real vector fields

The main purpose of this paper is to show, in the two-dimensional torus, a necessary and sufficient condition in order to certain perturbations of zero order of a system of constant real vector fields to be globally s-solvable. We are also interested in studying its global s-hypoellipticity. We present connections between these global concepts and a priori estimates. We also present two applications of our results for systems of operators with variable coefficients.     

Efficient directed ortho metalation-based route to cytotoxic furanonaphthoquinone natural products

The naturally-occuring furanonaphthoquinone 1e have been synthesized in good overall yield by a route involving directed ortho metalation (Scheme 1, 1 → 2).     

On Global Hypoellipticity

We consider a first order linear partial differential operator of principal type on a closed connected orientable two-dimensional manifold sending sections of one complex line bundle to sections of another. We prove that the assumption of global hypoellipticity of the operator implies a relation between the degrees of the line bundles and the Euler characteristic of the manifold.     

Large deviations for sample paths of quadratic variations of Gaussian processes

We prove a functional large deviations principle for the family of random functions