Preparation and Characterization of a Formally NiIV-Oxo Complex with a Triplet Ground State and Application in Oxidation Reactions.

High-valent first-row transition-metal-oxo complexes are important intermediates in biologically and chemically relevant oxidative transformations of organic molecules and in the water splitting reaction in (artificial) photosynthesis. While high-valent Fe- and Mn-oxo complexes have been characterized in detail, much less is known about their analogues with late transition metals. In this study, we present the synthesis and detailed characterization of a unique mononuclear terminal Ni-O complex. This compound, [Ni(TAML)(O)(OH)]3-, is characterized by an intense charge-transfer (CT) band around 730 nm and has an St = 1 ground state, as determined by magnetic circular dichroism spectroscopy. From extended X-ray absorption fine structure (EXAFS), the Ni-O bond distance is 1.84 Å. Ni K edge XAS data indicate that the complex contains a Ni(III) center, which results from an unusually large degree of Ni-O π-bond inversion, with one hole located on the oxo ligand. The complex is therefore best described as a low-spin Ni(III) complex (S = 1/2) with a bound oxyl (O•-) ligand (S = 1/2), where the spins of Ni and oxyl are ferromagnetically coupled, giving rise to the observed St = 1 ground state. This bonding description is roughly equivalent to the presence of a Ni-O single (σ) bond. Reactivity studies show that [Ni(TAML)(O)(OH)]3- is a strong oxidant capable of oxidizing thioanisole and styrene derivatives with large negative ρ values in the Hammett plot, indicating its electrophilic nature. The intermediate also shows high reactivity in C-H bond activation of hydrocarbons with a kinetic isotope effect of 7.0(3) in xanthene oxidation.

Validation of the Lithuanian multimorbidity treatment burden questionnaire (MTBQ) and its association with primary care patient characteristics.

BACKGROUND: The increasing prevalence of multimorbidity among older people in Lithuania and other Central-Eastern European countries leads to a greater patient treatment burden and puts additional pressure on healthcare services. OBJECTIVES: This study aimed to validate the Lithuanian version of the Multimorbidity Treatment Burden Questionnaire (MTBQ). METHODS: The Lithuanian version of the MTBQ was tested (2021-2022) with 789 patients from seven Lithuanian primary care centres who had two or more long-term conditions. The questionnaire translation's reliability, validity and dimensionality of the were assessed with Spearman's rank correlation, Cronbach's alpha, and factor reduction analysis. Treatment burden and its associations with sociodemographic and other indicators were analysed. RESULTS: Lithuanian version of MTBQ had good internal reliability (Cronbach's alpha 0.711), validity, factor reduction applicability, and interpretability. The MTBQ scores of the questionnaire had a negative association with the quality-of-life scale (r=-0.327, 95% CI [-0.389, -0.264]) and positive associations with the self-rated health scores (r = 0.230, 95% CI [0.163, 0.297]) and with the number of comorbidities (r = 0.164, 95% CI [0.097, 0.233]). Distribution of treatment burden was identified (none (19,4%), low (46,6%), medium (25%), high (9%)). High treatment burden was found to be associated with having five or more long-term diseases, taking five or more medications, having anxiety or depression and living in a rural area. CONCLUSION: The study's findings show that the MTBQ is applicable in assessing the treatment burden of multimorbid patients in Lithuania. Furthermore, the study demonstrates that Lithuanian patients with multimorbidity have average treatment burden scores similar to or higher than participants in previous MTBQ validation studies.

• The Lithuanian version of MTBQ features good content validity, internal reliability, and construct validity, and is suitable for assessing treatment burden of patients with multimorbidity in Lithuania.• The study demonstrated that Lithuanian patients with multimorbidity had average treatment burden scores similar to or higher than participants in previous MTBQ validation studies.

Bonding and the role of electrostatics in driving C-C bond formation in high valent organocopper compounds.

The electronic structures and contrasting reactivity of [Cu(CF3)4]- and [Cu(CF3)3(CH3)]- were probed using coupled cluster and ab initio valence bond calculations. The Cu-C bonds in these complexes were found to be charge shift bonds. A key finding is that electrostatics likely prevent [Cu(CF3)4]- from accessing a productive transition state for C-C bond formation while promote one for [Cu(CF3)3(CH3)]-. These results therefore highlight essential design criteria for Cu-mediated C-C/C-heteroatom bond formation.