Structural, Electrochemical, and Photochemical Properties of Mono- and Digold(I) Complexes Containing Mesoionic Carbenes

Triazolylidenes are a prominent class of mesoionic carbenes (MICs) that are currently widely used in organometallic chemistry. Usually the metal complexes of such ligands are used as homogeneous catalysts even though they have vast potential in other branches of chemistry. We present here three related gold(I) complexes with MIC ligands: a neutral mononuclear chlorido complex [AuCl(MIC)], a cationic mononuclear complex containing two MIC ligands [Au(MIC)2]BF4, and a dicationic digold(I) complex containing two di-MIC ligands [Au2(κ1,κ1,µ-di-MIC)2](BF4)2. The complexes were characterized by 1H and 13C{1H} NMR spectroscopy, mass spectrometry, and single-crystal X-ray diffraction. The gold(I) centers are linearly coordinated through either one MIC-C and chlorido donors or through two MIC-C donors. The triazolylidenes display a delocalized bonding situation within the ring. Additionally, a short Au–Au distance of about 3 Å is observed for the digold(I) complex. All complexes display reduction steps in their cyclic voltammograms, and these are assigned to the reduction of the MIC ligands, as opposed to the generation of gold(0). The complexes emit at ca. 500 nm, with lifetimes of several microseconds in deoxygenated solutions; the emission intensity and lifetime are strongly decreased by the presence of oxygen, supporting the triplet origin of the emissive state. The present results display the utility of MIC ligands for generating electro- and photoactive molecules

Use of ring-expanded diamino- and diamidocarbene ligands in copper catalyzed azide-alkyne "click" reactions

The two-coordinate ring-expanded N-heterocyclic carbene copper­(I) complexes [Cu­(RE-NHC)₂]⁺ (RE-NHC = 6-Mes, 7-<i>o</i>-Tol, 7-Mes) have been prepared and shown to be effective catalysts under neat conditions for the 1,3-dipolar cycloaddition of alkynes and azides. In contrast, the cationic diamidocarbene analogue [Cu­(6-MesDAC)₂]⁺ and the neutral species [(6-MesDAC)­CuCl]₂ and [(6-MesDAC)₂(CuCl)₃] show good activity when the catalysis is performed on water

Operative versus conservative treatment of apophyseal avulsion fractures of the pelvis in the adolescents: a systematical review with meta-analysis of clinical outcome and return to sports

Abstract Background Avulsion fractures of the pelvic apophyses typically occur in adolescent athletes due to a sudden strong muscle contraction while growth plates are still open. The main goals of this systematic review with meta-analysis were to summarize the evidence on clinical outcome and determine the rate of return to sports after conservative versus operative treatment of avulsion fractures of the pelvis. Methods A systematic search of the Ovid database was performed in December 2016 to identify all published articles reporting outcome and return to preinjury sport-level after conservative or operative treatment of avulsion fractures of the pelvis in adolescent patients. Included studies were abstracted regarding study characteristics, patient demographics and outcome measures. The methodological quality of the studies was assessed with the Coleman Methodology Score (CMS). Results Fourteen studies with a total of 596 patients met the inclusion criteria. The mean patient age was 14.3 ± 0.6 years and 75.5% of patients were male. Affected were the anterior inferior iliac spine (33.2%), ischial tuberosity (29.7%), anterior superior iliac spine (27.9%), iliac crest (6.7%) lesser trochanter (1.8%) and superior corner of the pubic symphysis (1.2%). Mean follow-up was 12.4 ± 11.7 months and most of the patients underwent a conservative treatment (89.6%). The overall success rate was higher in the patients receiving surgery (88%) compared to the patients receiving conservative treatment (79%) (p = 0,09). The rate of return to sports was 80% in conservative and 92% in operative treated patients (p = 0,03). Overall, the methodological quality of the included studies was low, with a mean CMS of 41.2. Conclusion On the basis of the present meta-analysis, the overall success and return to sports rate was higher in the patients receiving surgery. Especially in patients with fragment displacement greater 15 mm and high functional demands, surgical treatment should be considered

The German Radioimmunotherapy Registry: An Important Instrument of Quality Control in Innovative Treatment Strategies

E. Farrar's Mont Blanc - MB3 - photographed 1932. Digitisation and record funded by the Pilgrim Trust