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The α-metallated ylides [Ph 3 P-C-Z] - M + (with Z=SO 2 Tol or CN and M=Na or K) were used as versatile nucleophiles for the facile access to ylide-substituted compounds. Halogenations, alkylations, carbonylations and functionalization reactions with main group element halides were easily accomplished by simple trapping reactions with the appropriate electrophiles. X-ray crystallographic studies of all compounds - including the first structures of α-fluorinated P-ylides - showed remarkable differences in the ylide backbone depending on the substituents. In the fluorinated compounds, a change from a fully planar to a pyramidalized ylidic carbon centre was observed despite the strongly anion-stabilizing ability of the yldiide substituent. π-Donation from the ylide substituent also resulted in geometric restrictions depending on the steric and electronic properties of the introduced substituents., Competing Interests: The authors declare no conflict of interest.

The isolation and structural characterization of the cyanido-substituted metalated ylides [Ph 3 P-C-CN]M (1-M; M=Li, Na, K) are reported with lithium, sodium, and potassium as metal cations. In the solid-state, most different aggregates could be determined depending on the metal and additional Lewis bases. The crown-ether complexes of sodium (1-Na) and potassium (1-K) exhibited different structures, with sodium preferring coordination to the nitrogen end, whereas potassium binds in an unusual η 2 -coordination mode to the two central carbon atoms. The formation of the yldiide was accompanied by structural changes leading to shorter C-C and longer C-N bonds. This could be attributed to the delocalization of the free electron pairs at the carbon atom into the antibonding orbitals of the CN moiety, which was confirmed by IR spectroscopy and computational studies. Detailed density functional theory calculations show that the changes in the structure and the bonding situation were most pronounced in the lithium compounds due to the higher covalency., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Cooperative B-H bond activation reactions with thio- and iminophosphoryl tethered ruthenium-carbene complexes are reported. The complexes show surprisingly different reactivities towards the commonly employed boranes CatBH, PinBH and BH 3 ⋅LB as a result of different modes of metal-ligand cooperation. Although the iminophosphoryl system allows for selective 1,2-addition of the B-H bond across the Ru=C double bond, the sulfur analogue only delivers the 1,2-addition product for CatBH, whereas activation of BH 3 and PinBH lead to further insertion reactions in one or more sides of the Ru-C-P-S-ring. The different reactivities can be explained by the differences in the electronics of the carbene complexes and the phosphoryl tether and by the Lewis acidities of the boranes. DFT calculations show that the mechanism of the reactions either proceeds by an addition across the Ru=C bond with different regioselectivities or across the Ru-S linkage., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Low alanine aminotransferase (ALT) blood levels are associated with frailty and poor outcome in older adults. Therefore, we studied the association between ALT blood levels before rehabilitation and rehabilitation outcome in older adults following hip fracture surgery. A total of 490 older adults (age>60 years, mean age: 82.9±6.7 years, 82.0% women) admitted to rehabilitation following hip fracture surgery were included. The rehabilitation outcome was assessed by Functional Independence Measure (FIM) scores. ALT blood levels were documented between 1 and 6 months before rehabilitation. Patients with ALT blood levels over 40 IU/l possibly consistent with liver injury were excluded. The cohort was divided into two groups: patients with ALT more than 10 IU/l and patients with ALT less than or equal to 10 IU/l. Upon rehabilitation discharge, the FIM outcome measures (motor, cognitive, gain, efficiency) were significantly higher in patients with ALT more than 10 IU/l relative to patients with ALT less than or equal to 10 IU/l (P<0.05). A logistic regression analysis adjusted for age and sex showed that patients with ALT more than 10 IU/l were more likely to have higher (second to fourth upper quartiles) total FIM scores (>50), cognitive FIM scores (>16), and FIM efficiency (>0.228) upon rehabilitation discharge (odds ratio=1.56-1.78). However, this association was no longer significant following adjustment also for admission total FIM score, cognitive impairment, cancer, and albumin serum levels. High-normal ALT blood levels before rehabilitation are associated with a better rehabilitation outcome in older adults following hip fracture surgery. It may be used when data on admission FIM score, cognitive impairment, cancer, and albumin serum levels are not available.

The synthesis, electronic structure, and reactivity of the first Group 9 carbene complex, [Cp*IrL] [L=C(Ph2 PS)(SO2 Ph)] (2), based on a dilithio methandiide are reported. Spectroscopic as well as computational studies have shown that, despite using a late transition-metal precursor, sufficient charge transfer occurred from the methandiide to the metal, resulting in a stable, nucleophilic carbene species with pronounced metal-carbon double-bond character. The potential of this iridium complex in the activation of a series of E-H bonds by means of metal-ligand cooperation has been tested. These studies have revealed distinct differences in the reactivity of 2 compared to a previously reported ruthenium analogue. Whereas attempts to activate the O-H bond in different phenol derivatives resulted in ligand cleavage, H-H and Si-H activation as well as dehydrogenation of isopropanol have been accomplished. These reactions are driven by the transformation of the carbene to an alkyl ligand. Contrary to a previously reported ruthenium carbene system, the dihydrogen activation has been found to proceed by a stepwise mechanism, with the activation first taking place solely at the metal. The activated products further reacted to afford a cyclometalated complex through liberation of the activated substrates. In the case of triphenylsilane, cyclometalation could thus be induced by a substoichiometric (i.e., catalytic) amount of silane., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The transfer hydrogenation (TH) reaction of ketones with catalytic systems based on a methandiide-derived ruthenium carbene complex was investigated and optimised. The complex itself makes use of the noninnocent behaviour of the carbene ligand (M=CR2 →MH-C(H)R2 ), but showed only moderate activity, thus requiring long reaction times to achieve sufficient conversion. DFT studies on the reaction mechanism revealed high reaction barriers for both the dehydrogenation of iPrOH and the hydrogen transfer. A considerable improvement of the catalytic activity could be achieved by employing triphenylphosphine as additive. Mechanistic studies on the role of PPh3 in the catalytic cycle revealed the formation of a cyclometalated complex upon phosphine coordination. This ruthenacycle was revealed to be the active species under the reaction conditions. The use of the isolated complex resulted in high catalytic activities in the TH of aromatic as well as aliphatic ketones. The complex was also found to be active under base-free conditions, suggesting that the cyclometalation is crucial for the enhanced activity., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Si-H bond activation of a number of silanes via metal ligand cooperation in a carbene complex is reported. Thereby, the electronic flexibility of the carbene ligand allows for the activation via a unique mechanism with oxidative addition to an 18e species without a formal change in the number of valence electrons.

In the present study, 61 persons taken into police custody due to drunkenness were compared with 57 persons admitted to hospital due to intoxication with alcohol. The persons with alcohol problems taken into police custody numbered more younger men, fewer retired persons and the alcohol problems were more often acute intoxication than alcohol dependence. None of the persons placed in police custody were advised to seek help for their alcohol problems in contrast to 45 out of the 57 admitted to the hospital who started treatment. Detoxification in hospitals is far more suitable to motivate persons with alcohol problems to seek help. Detoxification should, for non criminal intoxicated people, be performed in hospitals.

In a double-blind clinical trial, a total of 463 volunteers were enrolled in a study designed to compare the effects of zinc gluconate lozenges (4.5 mg zinc) and a placebo for common cold. The tablets were to be taken every 1-1 1/2 waking hours at the first symptoms and for the following days until the common cold was over, but for no longer than 10 days. During the winter months of 1987 and 1988, 145 experienced a common cold and 130 completed the study. For final analysis, 61 patients in the zinc lozenge group and 69 patients in the placebo lozenge group were evaluated. Based on the patients' records the duration and severity of the common cold were compared. No statistically significant differences were found between the patient groups. Two recent studies using a five-time higher zinc dose per lozenge for common cold showed a significant, positive effect, but associated with frequent side-effects, first of all taste distortion. In the present study there was a weak tendency (not statistically significant, p = 0.12) towards more patients in the zinc lozenge group than in the placebo lozenge group reporting side-effects.

Based on the experience of 115 examinations, the authors first describes the normal radiological appearances on arthrography of the elbow joint. Subsequently, the radiological criteria are discussed which permit a diagnosis of intra- and para-articular soft tissue lesions due to closed trauma of the elbow joint. Arthrography with positive (water-soluble) contrast media enables one to diagnose rupture of the joint capsule and ligaments, and to diagnose with certainty subluxations of the various parts of the joint. Is is also possible to demonstrate haematomas between the muscles, which may lead to a reduction in joint function. Negative contrast medium (carbon dioxide, oxygen) permits the diagnosis of rupture of the insertion of the biceps.