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Novel silicon and tin compounds were synthesized by the reaction of lithium salts of 1,3-di-phenyl-1,1,3,3-tetramethyldisilazane H(DPTMDS) and 1,1,3,3,5,5-hexamethylcyclotrisilazane H3(HMCTS) with SiCl4 and SnCl4, respectively. The reactions with H(DPTMDS) yield the substitution products (DPTMDS)2SiCl2 and (DPTMDS)2SnCl2. In contrast, the reactions with the cyclic silazane H3(HMCTS) lead to a large variety of products due to the competition of substitution reactions and ring contractions. The resulting new compounds were characterized by elemental analyses, NMR spectroscopy, and single crystal X-ray structure analyses. [ABSTRACT FROM AUTHOR]

This review gives an overview of Si-, Ge- and Sn-compounds with (O,N)-bi- and -oligodentate ligands, which have the α-amino carboxylic acid motif N-C( R , R ')-C(=O)O in common ( R , R ' = H or hydrocarbyl). While the amino acids themselves are encountered as mono- and di-anionic ligands, modifications at the N-terminus (e.g., extension of the ligand backbone by, e.g., additional alkane carboxylic acid groups) give rise to a wealth of ligands, which bear the α-amino carboxylic acid motif. With particular interest in the coordination features of these ligands, crystallographically characterized complexes are the focus of this review.

Yb 5 Rh 6 Sn 18 crystallizes with a unique structural arrangement [space group P 4 2 / nmc , a = 9.6997(4) Å, c = 13.7710(7) Å], which is related with primitive cubic Yb 3 Rh 4 Sn 13 and body-centered tetragonal (Sn 1- x Tb x )Tb 4 Rh 6 Sn 18 types. X-ray absorption spectroscopy showed that Yb atoms exhibit temperature-dependent valence fluctuations (VF) ( i.e. , intermediate valence state). Its complex mechanism is corroborated by the fact that the well-pronounced maximum in magnetic susceptibility can only be fairly described by the Bickers-Cox-Wilkins model developed for a J = 3/2 multiplet, atypical for Yb ions. Both Hall and Seebeck coefficients revealed a switch of the sign, indicating the change of charge carrier type from electrons to holes between 120 and 220 K. Both these effects together with electrical resistivity and theoretical DFT calculations confirm Yb 5 Rh 6 Sn 18 to be a metal, which disobeys the free electron gas theory. 'Rattling' motion of Sn1 atoms within the enlarged 16-vertices distorted Frank-Kasper polyhedra, concluded from the specific heat measurements, is argued to be the main reason for the appearance of a phonon resonance behavior, resulting in an ultra-low thermal conductivity in the studied stannide.

Urea derivatives of the general motifs R 1 (N(SiMe 3 )C(O)NR 2 R 3 ) 2 and [R 1 (NC(O)NR 2 R 3 ) 2 SiMe 2 ] n (R 1 =difunctional organic linker, i. e., core of diisocyanate used; R 2 ,R 3 = H, n Pr; H,Ph; Et,Et) were synthesized by insertion of four different diisocyanates (1,6-HMDI, 2,4-TDI, 1,3-TMXDI and 4,4'-MDI) into aminotrimethylsilanes Me 3 SiNR 2 R 3 and diaminodimethylsilanes Me 2 Si(NR 2 R 3 ) 2 . The products obtained were analyzed by NMR and IR spectroscopy. Insertion into aliphatic aminosilanes was found to be favored for primary over secondary amino groups. For insertion into 4,4'-methylenebis(phenylisocyanate) (4,4'-MDI), good results were obtained for silanes derived from secondary amines as well. Insertion into aminosilanes with aromatic N-bound substituents turned out to be kinetically inhibited. Elucidation of molecular structures of the products by crystallography and NMR spectroscopy revealed interesting differences in N-Si connectivity, caused by steric and electronic effects of the reactants and migration of -SiMe 3 and -(SiMe 2 )- moieties., (© 2024 The Authors. Chemistry - An Asian Journal published by Wiley-VCH GmbH.)

Copper ores and concentrates thereof feature an increasingly notable content of impurities such as arsenic and other hazardous elements. As an alternative to the state-of-the-art partial roasting process, arsenic could be removed by the alkaline sulfide leaching of the copper concentrates. In order to optimize and understand the processes, knowledge of the speciation and oxidation states is essential. In addition to methods such as UV/Vis spectroscopy, chromatography and ICP/MS methods, 75 As NMR spectroscopy may be useful for the differentiation and quantification of the various species. Although arsenate(V) has been characterized by 75 As NMR some time ago, to our knowledge, there are no data on tetrathioarsenate(V) AsS 4 3- and the mixed oxygen/sulfur substituted mono-, di- and trithioarsenates(V) AsO x S 4- x 3- , x = 3, 2, 1, respectively. Therefore, we investigated several model solutions and samples from Cu-As leaching with 75 As NMR. The strongly alkaline conditions of the leaching solution proved to be very advantageous for that purpose. Both the tetrathioarsenate(V) and the mixed species AsO x S 4- x 3- ( x = 1-3) could be characterized and provide valuable data for the quantification of the material flows in the leaching process.

Here we discuss the successful utilization of a pair of deceased donor kidneys with bile-cast nephropathy. The donor had a kidney donor profile index of 48% and an acute kidney injury requiring continuous renal replacement therapy. Peak donor bilirubin was 40.5 mg/dL, and renal wedge biopsies showed bile-cast nephropathy. Both recipients had delayed graft function lasting up to 4 weeks. The 4-month biopsies showed mild interstitial fibrosis, tubular atrophy, and a resolution of bile casts. These kidney allografts showed the reversible course of cholemic nephropathy and the potential for increasing the utilization of previously discarded kidneys., Competing Interests: Disclosure The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation., (Copyright © 2023 American Society of Transplantation & American Society of Transplant Surgeons. Published by Elsevier Inc. All rights reserved.)

In chloroform solution, the reaction of bis(tert-butylamino)dimethylsilane (( t BuNH) 2 SiMe 2 ) and an α-amino acid (α-amino isobutyric acid, H 2 Aib ; D-phenylglycine, H 2 Phg ; L-valine, H 2 Val ) in the presence of N -methylimidazole (NMI) gave rise to the formation of the pentacoordinate silicon complexes (Aib)SiMe 2 -NMI , (Phg)SiMe 2 -NMI and (Val)SiMe 2 -NMI , respectively. Therein, the amino acid building block was a di-anionic bidentate chelator at the silicon atom. In solution, the complexes were involved in rapid coordination-dissociation equilibria between the pentacoordinate Si complex (e.g., (Aib)SiMe 2 -NMI ) and its constituents NMI and a five-membered silaheterocycle (e.g., (Aib)SiMe 2 ), as shown by 29 Si NMR spectroscopy. The energetics of the Lewis acid-base adduct formation and the competing solvation of the NMI molecule by chloroform were assessed with the aid of computational methods. In CDCl 3 solution, deuteration of the silaheterocycle NH group proceeded rapidly, with more than 50% conversion within two days. Upon cooling to -44 °C, the chloroform solvates of the adducts (Aib)SiMe 2 -NMI and (Phg)SiMe 2 -NMI crystallized from their parent solutions and allowed for their single-crystal X-ray diffraction analyses. In both cases, the Si atom was situated in a distorted trigonal bipyramidal coordination sphere with equatorial Si-C bonds and an equatorial Si-N bond (the one of the silaheterocycle). The axial positions were occupied by a carboxylate O atom of the silaheterocycle and the NMI ligand's donor- N -atom.

Introduction: Expedited out-of-sequence deceased donor kidney allocation is a strategy to avoid discards after early placement attempts have been unsuccessful. Our study aimed to assess outcomes and characteristics of these transplanted kidneys., Methods: KDPI matching was performed between expedited allocation (EA) and standard allocation (SA) deceased donor kidney transplants performed at our center., Results: Between 2018 and 2021, there were 225 EA offers, and 189 (84%) were transplanted. EA recipients were older (p = .007) and had shorter dialysis vintage (p < .0001). EA kidneys were likely to be nationally allocated (p < .001), have AKI (p < .0001) and longer CIT (p < .0001). There were no differences in EA and SA time-zero kidney biopsies (ci, p = .07; ct, p = .89; cv, p = .95; ah, p = .79). EA kidneys had more DGF (p = .0006), but there were no differences in DGF duration (p = .83), hospital length of stay (p = .43), 1- and 2-year eGFR (p = .16, p = .99), patient (p = .34), or death-censored graft (p = .66) survival., Conclusion: During this study period, our center transplanted 189 kidneys through EA following local-regional declines. These kidneys often came from AKI donors and had more DGF but had similar outcomes to KDPI-matched SA kidneys. Although it has been suggested that EA has the potential to worsen transplant disparities, transplant center level decisions on organ acceptance contribute to these variations., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: We sought to understand how safety culture may evolve during disruption, by using the COVID-19 pandemic as an example, to identify vulnerabilities in the system that could impact patient outcomes., Methods: A cross-sectional analysis of transplant personnel at a high-volume transplant center was conducted using the Safety Attitudes Questionnaire (SAQ). Survey responses were scaled and evaluated pre- and post-COVID-19 (2019 and 2021)., Results: Two-hundred and thirty-eight responses were collected (134 pre-pandemic and 104 post-pandemic). Represented organ groups included: kidney ( N  = 89;38%), heart ( N  = 18;8%), liver ( N  = 54;23%), multiple ( N  = 66;28%), and other ( N  = 10;4%). Responders primarily included nurses ( N  = 75;34%), administration ( N  = 50;23%), and physicians ( N  = 24;11%). Workers had high safety, job satisfaction, stress recognition, and working conditions satisfaction (score >75) both before and after the pandemic with overlapping responses across both timepoints. Stress recognition, safety, and working conditions improved post-COVID-19, but teamwork, job satisfaction, and perceptions of management were somewhat negatively impacted (all p  > 0.05)., Conclusions: Despite the serious health care disruptions induced by the pandemic, high domain ratings were notable and largely maintained in a high-volume transplant center. The SAQ is a valuable tool for healthcare units and can be used in longitudinal assessments of transplant culture of safety as a component of quality assurance and performance improvement initiatives., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Zhang, Wilson-Sheehan, Ruch, Wagler, Abidali, Lim, Chang, Fowler, Douglas and Mathur.)

Phenylgermaniumpyridine-2-olate PhGe(pyO) 3 (compound 1Ge ) and CuCl react with the formation of the heteronuclear complex Ph(pyO)Ge(μ 2 -pyO) 2 CuCl ( 2Ge' ) rather than forming the expected compound PhGe(μ 2 -pyO) 3 CuCl ( 2Ge ). Single-point calculations (at the B2T-PLYP level) of the optimized molecular structures confirmed the relative stability of isomer 2Ge' over 2Ge and, for the related silicon congeners, the relative stability of 2Si over 2Si' . Decomposition of a solution of 2Ge' upon access to air provided access to some crystals of the copper(II) compound PhGe(μ 2 -pyO) 4 CuCl ( 3Ge ). Compounds 2Ge' and 3Ge were characterized by single-crystal X-ray diffraction analyses, and the Ge-Cu bonds in these compounds were analyzed with the aid of quantum chemical calculations, e.g., Natural Bond Orbital analyses (NBO), Non-Covalent Interactions descriptor (NCI), and topology of the electron density at bond critical point using Quantum Theory of Atoms-In-Molecules (QTAIM) in conjunction with the related silicon compounds PhSi(μ 2 -pyO) 3 CuCl ( 2Si ), PhSi(μ 2 -pyO) 4 CuCl ( 3Si ), as well as the potential isomers Ph(pyO)Si(μ 2 -pyO) 2 CuCl ( 2Si' ) and PhGe(μ 2 -pyO) 3 CuCl ( 2Ge ). Pronounced Cu→Ge (over Cu→Si) lone pair donation was found for the Cu(I) compounds, whereas in Cu(II) compounds 3Si and 3Ge, this σ-donation is less pronounced and only marginally enhanced in 3Ge over 3Si ., Competing Interests: The authors declare no conflicts of interest.

Background: The Centers for Medicare and Medicaid Services is a major payer for abdominal transplant services. Reimbursement reductions could have a major impact on the transplant surgical workforce and hospitals. Yet government reimbursement trends in abdominal transplantation have not been fully characterized., Methods: We performed an economic analysis to characterize changes in inflation-adjusted trends in Medicare surgical reimbursement for abdominal transplant procedures. Using the Medicare Fee Schedule Look-Up Tool, we performed a procedure code-based surgical reimbursement rate analysis. Reimbursement rates were adjusted for inflation to calculate overall changes in reimbursement, overall year-over-year, 5-year year-over-year, and compound annual growth rate from 2000 to 2021., Results: We observed declines in adjusted reimbursement of common abdominal transplant procedures, including liver (-32.4%), kidney with and without nephrectomy (-24.2% and -24.1%, respectively), and pancreas transplant (-15.2%) (all, P < .05). Overall, the yearly average change for liver, kidney with and without nephrectomy, and pancreas transplant were -1.54%, -1.15%, -1.15%, and -0.72%. Five-year annual change averaged -2.69%, -2.35%, -2.64%, and -2.43%, respectively. The overall average compound annual growth rate was -1.27%., Conclusion: This analysis depicts a worrisome reimbursement pattern for abdominal transplant procedures. Transplant surgeons, centers, and professional organizations should note these trends to advocate sustainable reimbursement policy and to preserve continued access to transplant services., (Copyright © 2023. Published by Elsevier Inc.)

Condensation reactions of chlorosilanes (SiCl 4 and CH 3 SiCl 3 ) and bis(trimethylsilyl)ethers of rigid, quasi-linear diols (CH 3 ) 3 SiO- AR -OSi(CH 3 ) 3 ( AR = 4,4'-biphenylene ( 1 ) and 2,6-naphthylene ( 2 )), with release of (CH 3 ) 3 SiCl as a volatile byproduct, afforded novel hybrid materials that feature Si-O-C bridges. The precursors 1 and 2 were characterized using FTIR and multinuclear ( 1 H, 13 C, 29 Si) NMR spectroscopy as well as single-crystal X-ray diffraction analysis in case of 2 . Pyridine-catalyzed and non-catalyzed transformations were performed in THF at room temperature and at 60 °C. In most cases, soluble oligomers were obtained. The progress of these transsilylations was monitored in solution with 29 Si NMR spectroscopy. Pyridine-catalyzed reactions with CH 3 SiCl 3 proceeded until complete substitution of all chlorine atoms; however, no gelation or precipitation was found. In case of pyridine-catalyzed reactions of 1 and 2 with SiCl 4 , a Sol-Gel transition was observed. Ageing and syneresis yielded xerogels 1A and 2A , which exhibited large linear shrinkage of 57-59% and consequently low BET surface area of 10 m 2 ⋅g -1 . The xerogels were analyzed using powder-XRD, solid state 29 Si NMR and FTIR spectroscopy, SEM/EDX, elemental analysis, and thermal gravimetric analysis. The SiCl 4 -derived amorphous xerogels consist of hydrolytically sensitive three-dimensional networks of SiO 4 -units linked by the arylene groups. The non-hydrolytic approach to hybrid materials may be applied to other silylated precursors, if the reactivity of the corresponding chlorine compound is sufficient.

Concerns regarding outcomes and early resource utilization are potential deterrents to broader use of kidneys at risk for delayed graft function (DGF). We assessed outcomes specific to kidneys with DGF that required early readmission following transplant. Three groups were identified: 1) recipients with DGF not requiring readmission, 2) recipients with DGF having an isolated readmission, and 3) recipients with DGF requiring ≥2 readmissions. Most recipients either required a single readmission (26.8%, n = 247) or no readmission (56.1%, n = 517); 17.1% ( n = 158), had ≥2 readmissions. Recipients requiring ≥2 readmissions were likely to be diabetic (53.8%, p = 0.04) and have longer dialysis vintage ( p = 0.01). Duration of DGF was longer with increasing number of readmissions ( p < 0.001). There were no differences in patient survival for those with DGF and 0, 1 and ≥2 readmissions ( p = 0.13). Graft survival, however, was lower for those with ≥2 readmissions ( p < 0.0001). This remained true when accounting for death-censored graft loss ( p = 0.0012). Additional subgroup analysis was performed on mate kidneys with and without DGF and mate kidneys, both with DGF, with and without readmissions. For these subgroups, there were no differences in patient or graft survival. As a whole, patients with DGF have excellent outcomes, however, patients with DGF requiring ≥2 readmissions have lower graft survival. A better understanding of recipient variables contributing to multiple readmissions may allow for improvements in the utilization of DGF at-risk kidneys., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jadlowiec, Frasco, Macdonough, Wagler, Das, Budhiraja, Mathur, Katariya, Reddy, Khamash and Heilman.)

Hepatocellular carcinoma (HCC) is one of the leading indications for liver transplantation and has been the treatment of choice due to the oncologic benefit for patients with advanced chronic liver disease (AdvCLD) and small tumors for the last 25 years. For HCC patients undergoing liver transplantation, alpha fetoprotein (AFP) has increasingly been applied as an independent predictor for overall survival, disease free recurrence, and waitlist drop out. In addition to static AFP, newer studies evaluating the AFP dynamic response to downstaging therapy show enhanced prognostication compared to static AFP alone. While AFP has been utilized to select HCC patients for transplant, despite years of allocation policy changes, the US allocation system continues to take a uniform approach to HCC patients, without discriminating between those with favorable or unfavorable tumor biology. We aim to review the history of liver allocation for HCC in the US, the utility of AFP in liver transplantation, the implications of weaving AFP as a biomarker into policy. Based on this review, we encourage the US transplant community to revisit its HCC organ allocation model, to incorporate more precise oncologic principles for patient selection, and to adopt AFP dynamics to better stratify waitlist dropout risk.

Dual kidney transplantation (DKT), utilizing two adult kidneys from the same donor for one recipient, has been used as a way to expand the available donor pool. These kidneys often come from high Kidney Donor Profile Index donors (KDPI > 85%). Data comparing outcomes between high KDPI DKT and single kidney transplants (SKT) remain limited. We assessed outcomes of 336 high KDPI kidney transplants performed at our center; 11.0% (n = 37) were DKT. Recipients of DKT were older (P = .02) and donors had a higher KDPI score (median 96% vs. 91%, P < .0001). DKT operative time was higher compared to SKT (+1.4 hours, P < .0001). There were no differences in delayed graft function (54.1% vs. 51.5%, P = .77) and hospital length of stay (median 4.0 vs. 3.0 days, P = .21) between DKT and SKT. Grade I Clavien-Dindo complications occurred in 8.1% of DKT and 13.7% of SKT (P = .008). There were no grade IVa, IVb, or V complications in either group. DKT had more glomerulosclerosis (P = .04), interstitial fibrosis (P = .02), tubular atrophy (P = .01), and arterial thickening (P = .03) on 1-year protocol biopsies. Estimated glomerular filtration was higher for DKT at 1- (P = .004) and 2-years post-transplant (P = .01). There were no differences in patient (HR 1.3, 95% CI .5-3.3, P = .58) or graft (HR 1.1, 95% CI .5-2.3, P = .83) survival. Good outcomes can be achieved with DKT using high KDPI kidneys with moderate chronic changes. DKT is a good option to help further utilize high KDPI kidneys and minimize discard., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The reaction between 2,3-dimercaptopropane-1-sulfonate (DMPS, unithiol) and four phenylarsonic(V) acids, i.e. phenylarsonic acid (PAA), 4-hydroxy-3-nitrophenylarsonic acid (HNPAA), 2-aminophenylarsonic acid (o-APAA) and 4-aminophenylarsonic acid (p-APAA), is investigated in aqueous solution. The pentavalent arsenic compounds are reduced by DMPS to their trivalent analogs and instantly chelated by the vicinal dithiol, forming covalent As-S bonds within a five-membered chelate ring. The different types and positions of polar substituents at the aromatic ring of the arsonic acids influence the reaction rates in the same way as observed for reaction with glutathione (GSH), as well as the syn/anti molar ratio of the diastereomeric products, which was analyzed using time- and temperature-dependent nuclear magnetic resonance (NMR) spectroscopy. Addition of DMPS to the conjugate formed by a phenylarsonic(V) acid and the biologically relevant tripeptide GSH showed the immediate replacement of GSH by chelating DMPS, underlining the importance of dithiols as detoxifying agent., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Starting from [Ru(pyO) 2 (nbd)] 1 and a N,P,N-tridentate ligand ( 2a : PhP(pic) 2 , 2b : PhP(pyO) 2 ) (nbd = 2,5-norbornadiene, pic = 2-picolyl = 2-pyridylmethyl, pyO = 2-pyridyloxy = pyridine-2-olate), the compounds [PhP(μ-pic) 2 (μ-pyO)Ru(κ 2 -pyO)] ( 3a ) and [PhP(μ-pyO) 3 Ru(κ 2 -pyO)] ( 3b ), respectively, were prepared. Reaction of compounds 3 with CO and CN t Bu afforded the opening of the Ru(κ 2 -pyO) chelate motif with the formation of compounds [PhP(μ-pic) 2 (μ-pyO)Ru(κ- O -pyO)(CO)] ( 4a ), [PhP(μ-pic) 2 (μ-pyO) 2 Ru(CN t Bu)] ( 5a ), [PhP(μ-pyO) 4 Ru(CO)] ( 4b ) and [PhP(μ-pyO) 4 Ru(CN t Bu)] ( 5b ). In dichloromethane solution, 4a underwent a reaction with the solvent, i.e., substitution of the dangling pyO ligand by chloride with the formation of [PhP(μ-pic) 2 (μ-pyO)Ru(Cl)(CO)] ( 6a ). The new complexes 3a , 4a , 5a , 5b and 6a were characterized by single-crystal X-ray diffraction analyses and multi-nuclear ( 1 H, 13 C, 31 P) NMR spectroscopy. The different coordination behaviors of related pairs of molecules (i.e., pairs of 3 , 4 and 5 ), which depend on the nature of the P-Ru-bridging ligand moieties (μ-pic vs. μ-pyO), were also studied via computational analyses using QTAIM (quantum theory of atoms in molecules) and NBO (natural bond orbital) approaches, as well as the NCI (non-covalent interactions descriptor) for weak intramolecular interactions.

The insertion of carbon dioxide into the Si-N bonds of aminodisilanes ((RR'N) n Me 3- n Si) 2 affords carbamoyloxydisilanes ((RR'NC(O)O) n Me 3- n Si) 2 . Some of the obtained insertion products feature pentacoordinate silicon atoms in the solid state and in solution, with two carbamoyloxy moieties bridging the Si-Si bond. The aminodisilanes and their insertion products were extensively analyzed, including single-crystal X-ray structure analyses. The temperature dependence of the higher coordination was investigated using variable temperature NMR experiments., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Background: The risk of donor-derived severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in solid organ (heart, lung, liver, kidney, pancreas, and intestine) transplant recipients is poorly understood. Since hematogenous transmission of SARS-CoV-2 has not been documented to date, nonlung solid organs might be suitable for transplantation since they likely portend a low risk of viral transmission., Methods: Abdominal solid organs from SARS-CoV-2-infected donors were transplanted into uninfected recipients., Results: Between April 18, 2021, and October 30, 2021, we performed transplants of 2 livers, 1 simultaneous liver and kidney, 1 kidney, and 1 simultaneous kidney and pancreas from SARS-CoV-2-infected donors into 5 uninfected recipients. None of the recipients developed SARS-CoV-2 infection or coronavirus disease 2019, and when tested, allograft biopsies showed no evidence of SARS-CoV-2 RNA., Conclusions: Transplanting nonlung organs from SARS-CoV-2-infected donors into uninfected recipients demonstrated no evidence of virus transmission., Competing Interests: The authors declare no funding or conflicts of interest., (Copyright © 2022 The Author(s). Transplantation Direct. Published by Wolters Kluwer Health, Inc.)

Inspired by the known complex [PhP(μ-PyO) 4 Ru(CO)] (PyO = 2-pyridyloxy), the family of group 15 paddle-wheel complexes has been expanded to [PhPn(μ-PyO) 4 Ru(L)] (Pn = P, As, Sb; L = NCMe, CO). Solvent-dependent reversible switching between [PhAs(μ-PyO) 4 Ru(NCMe)] and [PhAs(μ-PyO) 3 Ru(κ 2 -PyO)] was detected. Electrochemical investigations of the [PhPn(μ-PyO) 4 Ru(L)] complexes showed reversible oxidation of the complexes with L = NCMe and back-formation of the complexes with L = NCMe upon oxidation of the complexes with L = CO in NCMe. In the series of [PhPn(μ-PyO) 4 Ru(L)] complexes, the Pn→Ru bonding mode is shifted from L-type Pn to X-type upon going from Pn = P and As to Pn = Sb, resulting in a pronounced electron-rich Ru site in the latter case. The easily accessible complex [PhSb(μ-PyO) 4 RuCl] exhibits reversible electrochemical and coordinative exchange with its reduced analogue [PhSb(μ-PyO) 4 Ru(NCMe)] under retention of the paddle-wheel motif and Sb-Ru bond properties.

Yb 3 Co 4 Ge 13 is the first example of a Remeika phase with a 3 D + 3 [space group P 4̄3 n ( α ,0,0)000(0, α ,0)000(0,0, α )000; a = 8.72328(1) Å, α = 0.4974(2)] modulated crystal structure. A slight shift of the composition towards higher Yb-content ( i.e. Yb 3.2 Co 4 Ge 12.8 ) leads to the disappearance of the satellite reflections and stabilization of the disordered primitive cubic [space group Pm 3̄ n , a = 8.74072(2) Å] Remeika prototype structure. The stoichiometric structurally modulated germanide is a metal with hole-like charge carriers, where Yb-ions are in a temperature-dependent intermediate valence state varying from +2.60 to +2.66 for the temperature range 85-293 K. The valence fluctuations have been investigated by means of temperature dependent X-ray absorption spectroscopy, magnetic susceptibility and thermopower measurements.

The reversible hydrogenation of aminoalanes employing activated aluminium and piperidine has been explored. A selection of transition metal (TM) compounds have been investigated as additives for producing TM-activated aluminium (TM = Ti, Zr, Hf and Y). The effect of these additives on the activation of aluminium with respect to hydrogenation of an aluminium/piperidinoalane system has been studied. It has been shown that Ti, Zr and Hf can efficiently promote the activation of aluminium for its hydrogenation. The experiments performed showed that the TM activity for the piperidinoalane formation decreases in the order Zr > Hf > Ti > Y. Using multinuclear NMR spectroscopy, the reversibility of this piperidinoalane-based hydrogenation system has been evidenced, demonstrating a potential pathway for hydrogen storage in aminoalanes. The syntheses of piperidinoalanes as well as their structural and spectroscopic characterisation are described. Single-crystal X-ray diffraction analyses of [pip2AlH]2 and [pip3Al]2 (pip = 1-piperidinyl, C5H10N) revealed dimers containing a central [AlN]2 unit.

Poly- and single-crystalline samples of In0.67□0.33In2S4 thiospinel were obtained by various powder metallurgical and chemical vapor transport methods, respectively. All synthesized samples contained β-In0.67□0.33In2S4 modification only, independent of the synthesis procedure. High-resolution powder X-ray diffraction (PXRD) experiments at 80 K enabled the observation of split tetragonal reflections (completely overlapped at room temperature), which prove the correctness of the crystal structure model accepted for the β-polymorph. Combining single-crystal XRD, transmission electron microscopy and selected-area electron diffraction studies, the presence of three twin domains in the as-grown crystals was confirmed. A high temperature PXRD study revealed both abrupt (in full widths at half maxima of main reflections and in unit-cell volume) and gradual (in intensity of satellites and c/a ratio) changes in the vicinity of the α-β phase transition. These observations, together with a clear endothermic peak in the heat capacity, the magnitude of enthalpy/entropy change and the temperature dependence of electrical resistivity (associated with hysteresis), hinted towards the 1st order type of transition. Three scenarios, based on Rietveld refinement analysis, were considered for the description of the crystal structure evolution from β- to α-modification, including the (3+3)D-modulated cubic structure at 693 K as an intermediate state during the β-α transformation. The Seebeck coefficient, electrical resistivity and thermal conductivity were not only influenced by phase transition, but also by annealing conditions (S-poor or S-rich atmosphere). Density functional theory calculations predicted semiconducting behavior of In0.67□0.33In2S4, as well as instability of the fictitious InIn2S4 thiospinel.

29Si enrichment would be advantageous for many NMR studies of the structural properties of sol-gel derived materials. The required starting materials (29Si enriched alkoxysilanes), however, are expensive and difficult to provide. Here we present a scalable, reliable synthesis of 29Si enriched tetraethoxysilane starting from silicon dioxide or elemental silicon with a total yield up to 75%.

In the course of our investigations of the coordination chemistry of trivalent antimony (Sb) compounds, we studied heteronuclear complexes formed in reactions of the compounds RSb(pyS) 2 (R = pyS, Ph; pyS - = pyridine-2-thiolate) with [Pt(PPh 3 ) 4 ], i.e., complexes [(R)Sb(μ-pyS) 2 Pt(PPh 3 )] (R = pyS, 1 ; R = Ph, 2 ). The reaction of 1 with o -chloranil proceeds cleanly with elimination of 2,2'-dipyridyl disulfide and formation of the salt [(PPh 3 )Pt(μ-pyS) 2 Sb(μ-pyS) 2 Pt(PPh 3 )] + [Sb(C 6 Cl 4 O 2 ) 2 ] - ( 3 III ), which features the cation 3 + . The charge-neutral, unsymmetrically substituted compound [(PPh 3 )Pt(μ-pyS) 2 Sb(μ-pyS) 2 Pt(κ S -pyS)] ( 4 ) can be accessed by the reaction of 3 + with LipyS. The oxidation of 2 with o -chloranil furnishes the complex [(κ- O , O -C 6 Cl 4 O 2 )PhSb(μ-pyS) 2 Pt(PPh 3 )] ( 5 ). The oxidation of 1 with PhICl 2 afforded the paddlewheel-shaped complex [Sb(μ-pyS) 4 PtCl] ( 6 ). Moreover, compound 6 was obtained by the reaction of Sb(pyS) 3 with [PtCl(pyS)(PPh 3 )]. The polarization of Pt-Sb bonds of compounds 1 - 6 was investigated by natural localized molecular orbital (NLMO) calculations, which suggest X-type ligand character (covalent Pt-Sb bonds) for 1 and 2 , whereas the Sb ligand of 6 reflects Z-type character (dative Pt→Sb bonds). In 3 + , 4 , and 5 , high contributions of the reverse, i.e., L-type (dative Pt←Sb bonds), were observed. In conjunction with the results of NLMO analyses, 121 Sb Mössbauer spectroscopy proves that complexes 1 - 6 represent essentially trivalent Sb complexes with either a free lone pair (LP) at the Sb atom ( 1 , 2 , and 6 ) or LP character involved in L-type Pt←Sb coordination ( 3 + , 4 , and 5 ).

Invited for this month's cover is the group of Marcus Herbig from the TU Bergakademie in Freiberg. The cover picture shows the reaction of CO 2 with a silyl derivative of the biogenic amine ethanolamine. The role of CO 2 as a contributor to climate change makes "carbon capture" a desirable goal. However, in addition to simply capture CO 2 , aminosilanes form silylcarbamates, which represent starting materials for a variety of crucial chemicals. Thus, the entrapped CO 2 represents a useful C 1 building block. The ESF-funded Junior Research Group CO 2 -Sil at the TU Bergakademie Freiberg (represented by their Logo and location) pursues that kind of goals. CO 2 -Sil studies these key reactions of CO 2 insertion in depth by syntheses, quantum chemical calculations and calorimetric experiments. CO 2 brought to the ground by our method shall be feedstock for various branches in chemistry. Read the full text of their Full Paper at 10.1002/open.201900269., (© 2020 Wiley‐VCH GmbH.)