Radical anions of 1,1-azoliumdithiocarboxylates.

The 1,1-azoliumdithiocarboxylate cAAC-CS (1a) was prepared and its redox chemistry was evaluated and compared to NHC based dithiocarboxylates IDipp-CS (1b) and IMes-CS (1c). Radical anions [carbene-CS]˙ were prepared by metallic reduction as the potassium or magnesium ion complexes [K(18-crown-6)(cAAC-CS)] (2a), [K(18-crown-6)(NHC-CS)] (NHC = IDipp: 2b, IMes: 2c), and [Mg(NacNac)(cAAC-CS)] (3) and extensively characterized (SC-XRD, EPR, UV/VIS/NIR, DFT). These complexes represent the first examples of isolated radical anions of 1,1-dithiolenes.

Construction of a Boron Chain on a Single Metal by Dehydrocoupling of Borane Ligands.

Borane coordination, B-H borane bond activation, and borane catenation via metal-mediated dehydrocoupling to form electron-precise B-B bonds are reported. The reaction of -[M(IMes)Cl] (M = W, Mo) (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) with borates Li[BHR] (R = Mes, Dur; Mes = 2,4,6-MeCH and Dur = 2,3,5,6-MeCH) afforded the complexes [M(IMes)(η-HBR)(η-HBR)] (M = W: R = Mes , R = Dur ; M = Mo: R = Mes , R = Dur ). Three borane ligands are coordinated in to the group 6 metal atom via five (σ-B-H) bonds.

1-1,2,3-Triazol-5-ylidenes as Catalytic Organic Single-Electron Reductants.

Most of the known single-electron reductants are either metal based reagents, used in a stoichiometric amount, or a combination of an organic species and a photocatalyst. Here we report that 1-1,2,3-triazol-5-ylidenes act not only as stoichiometric one-electron donors but also as catalytic organic reducing agents, without the need of a photocatalyst. As a proof of concept, we studied the reduction of quinones, which are well-known electron conveyors that are involved in various biological and industrial processes.

A step-for-step main-group replica of the Fischer carbene synthesis at a borylene carbonyl.

The Fischer carbene synthesis, involving the conversion of a transition metal (TM)-bound CO ligand to a carbene ligand of the form [=C(OR')R] (R, R' = organyl groups), is one of the seminal reactions in the history of organometallic chemistry. Carbonyl complexes of p-block elements, of the form [E(CO)] (E = main-group fragment), are much less abundant than their TM cousins; this scarcity and the general instability of low-valent p-block species means that replicating the historical reactions of TM carbonyls is often very difficult. Here we present a step-for-step replica of the Fischer carbene synthesis at a borylene carbonyl involving nucleophilic attack at the carbonyl carbon followed by electrophilic quenching at the resultant acylate oxygen atom.

Hearing Aid Use Time Is Causally Influenced by Psychological Parameters in Mildly Distressed Patients with Chronic Tinnitus and Mild-to-Moderate Hearing Loss.

Background: Hearing aids (HAs) can improve tinnitus-related distress (TRD) and speech-comprehension (SC) in silence or at 55 dB noise-interference (SC_55 dB) in patients with chronic tinnitus and mild-to-moderate hearing loss. However, the role of HA use time in relation to psychological, audiological, or self-reported tinnitus characteristics is under-investigated.

Methods: We examine 177 gender-stratified patients before (t) and after an intervention comprising binaural DSL algorithm-based HA fitting and auditory training (t) and at a 70-day follow up [t].