Hydrogen Atom Abstraction Thermodynamics of a μ-1,2-Superoxo Dicopper(II) Complex.

Pyrazolate-based μ-1,2-peroxo dicopper(II) complex 1 undergoes clean 1e oxidation at low potential (-0.59 V vs Fc/Fc) to yield the rather stable μ-1,2-superoxo dicopper(II) complex 3, which was characterized by spectroscopic methods (ν̃(O-O) = 1070 cm, Δ(O-O) = -59 cm) and analyzed by DFT calculations. 3 is also formed via H-atom abstraction from the corresponding μ-1,1-hydroperoxo dicopper(II) complex 2, while 3 itself is able to abstract H-atoms from weaker X-H bonds such as TEMPO-H to re-form 2.

Synthesis of Carbonates from Alcohols and CO.

Alcohols are ubiquitous compounds in nature that offer modular building blocks for synthetic chemistry. Here we discuss the most recent development of different classes of alcohols and their coupling chemistry with carbon dioxide as to afford linear and cyclic carbonates, the challenges associated with their formation, and the potential of this chemistry to revive a waste carbon feed stock.

Reductive Transformations of a Pyrazolate-Based Bioinspired Diiron-Dinitrosyl Complex.

Flavo-diiron nitric oxide reductases (FNORs) are a subclass of nonheme diiron proteins in pathogenic bacteria that reductively transform NO to NO, thereby abrogating the nitrosative stress exerted by macrophages as part of the immune response. Understanding the mechanism and intermediates in the NO detoxification process might be crucial for the development of a more efficient treatment against these bacteria. However, low molecular weight models are still rare, and only in a few cases have their reductive transformations been thoroughly investigated.

Proton-Induced, Reversible Interconversion of a μ-1,2-Peroxo and a μ-1,1-Hydroperoxo Dicopper(II) Complex.

The μ-1,2-peroxo dicopper(II) complex (2) of a compartmental bis(tetradentate) pyrazolate-based ligand is shown to convert, upon protonation, to the corresponding μ-1,1-hydroperoxo dicopper(II) complex (3). The transformation is cleanly reversed with base, and an apparent pK(a) = 22.2 ± 0.

Resting-state networks in healthy adult subjects: a comparison between a 32-element and an 8-element phased array head coil at 3.0 Tesla.

Background: Little research exists on the influence of a magnetic resonance imaging (MRI) head coil's channel count on measured resting-state functional connectivity.

Purpose: To compare a 32-element (32ch) and an 8-element (8ch) phased array head coil with respect to their potential to detect functional connectivity within resting-state networks.

Material And Methods: Twenty-six healthy adults (mean age, 21.

A ferromagnetically coupled (S = 1) peroxodicopper(II) complex.

Copper enzymes play important roles in the binding and activation of dioxygen in biological systems. Key copper/dioxygen intermediates have been identified and studied in synthetic analogues of the metalloprotein active sites, including the μ-η(2):η(2)-peroxodicopper(II) motif relevant to type III dicopper proteins. Herein, we report the synthesis and characterization of a bioinspired dicopper system that forms a stable μ-η(1):η(1)-peroxo complex whose Cu-O-O-Cu torsion is constrained to around 90° by ligand design.

The impact of cardiac perception on emotion experience and cognitive performance under mental stress.

Mental stress evokes several physiological responses such as the acceleration of heart rate, increase of electrodermal activity and the release of adrenaline. Moreover, physiological stress responses interact with emotional and behavioral stress responses. In the present study we provide evidence that viscero-sensory feedback from the heart (cardiac perception) is an important factor modulating emotional and cognitive stress responses.

Crowning of coinage metal pyrazolates: double-decker homo- and heteronuclear complexes with synergic emissive properties.

A new pyrazole ligand with flexible thioether chelate arms was synthesized and was used to obtain an unprecedented class of hexanuclear coinage metal complexes of general formula [MM'L]3Y3 (M, M' = Cu, Ag, Au; Y = OTf, BF4). Three of them were characterized by X-ray crystallography, namely, homometallic [Ag2L]3(OTf)3 and [Ag2L]3(BF4)3 as well as heterometallic [CuAgL]3(OTf)3, revealing that the classical [M(μ-pz)]3 core is crowned by a second deck of S-bound M' ions. Depending on the solvent, these oligonuclear systems undergo rapid dynamics and show cation-anion aggregation in solution, which has been investigated by DOSY and temperature dependent NMR spectroscopy.