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Multi-modal analgesic strategies, including regional anesthesia techniques, have been shown to contribute to a reduction in the use of opioids and associated side effects in the perioperative setting. Consequently, those so-called multi-modal approaches are recommended and have become the state of the art in perioperative medicine. In the majority of intensive care units (ICUs), however, mono-modal opioid-based analgesic strategies are still the standard of care. The evidence guiding the application of regional anesthesia in the ICU is scarce because possible complications, especially associated with neuraxial regional anesthesia techniques, are often feared in critically ill patients. However, chest and abdominal wall analgesia in particular is often insufficiently treated by opioid-based analgesic regimes. This review summarizes the available evidence and gives recommendations for peripheral regional analgesia approaches as valuable complements in the repertoire of intensive care physicians' analgesic portfolios. [ABSTRACT FROM AUTHOR]

Mechanical circulatory support has proven effective in managing postcardiotomy cardiogenic shock by stabilizing patients' hemodynamics and ensuring adequate organ perfusion. Among the available device modalities, the combination of extracorporeal life support and a microaxial flow pump for left ventricular unloading has emerged as a valuable tool in the surgical armamentarium. In this publication, we provide recommendations for the application and weaning of temporary mechanical circulatory support in cardiogenic shock patients, derived from a consensus among leading cardiac centers in German-speaking countries. [ABSTRACT FROM AUTHOR]

This account highlights the versatility of phosphanylphosphonates, which can be used for the preparation of phosphorus-containing π-systems and as reagents for the reductive coupling of carbonyl compounds to alkenes. Phosphanylphosphonates with metal fragments coordinated to the P-lone pair have been known for a long time and they have been used for the synthesis of phosphaalkenes by means of the phospha-Horner–Wadsworth–Emmons reaction. With the original aim of incorporating phosphorus heteroatoms into classical all-carbon ethynylethene scaffolds, we entered the field of phosphanylphosphonates with the discovery that these compounds engage in complex cascade reactions with acetylenic ketones, forming 1,2-oxaphospholes, cumulenes, and bisphospholes. Later, we synthesized the first metal-free phosphanylphosphonate, which reacts with aldehydes to yield phosphaalkenes, but gives phospholones when diacetylenic ketones are used as substrates. In the final part of the account, we outline our discovery and the development of an unprecedented carbonyl–carbonyl cross-coupling reaction. This protocol offers a straightforward method for the synthesis of nonsymmetric 1,2-disubstituted alkenes directly from two dissimilar aldehydes. 1 Combining Acetylenes with Phosphaalkenes 2 Synthetic Examples of Acetylenic Phosphaalkenes 3 The Phospha-Horner–Wadsworth–Emmons Approach to Phosphaalkenes 3.1 Metal-Coordinated Phosphanylphosphonates 3.2 Mechanism of the Phospha-Horner–Wadsworth–Emmons Reaction 3.3 The First Metal-Free Phosphanylphosphonate and Its Reactivity with Aldehydes 4 Reactions with Acetylenic Ketones 4.1 Metal-Coordinated Phosphanylphosphonate and Monoacetylenic Ketones 4.2 Metal-Coordinated Phosphanylphosphonate and Diacetylenic Ketones 4.3 Metal-Free Phosphanylphosphonate and Diacetylenic Ketones 5 Metal-Free Phosphanylphosphonate as a Coupling Reagent for Aldehydes 6 E -Alkenes by the Reductive Coupling of Two Aldehydes 7 Conclusions and Outlook [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) corrupts the outcome of about 50% of all critically ill patients. We investigated the possible contribution of the pathology acidemia on the development of AKI. Pigs were exposed to acidemia, acidemia plus hypoxemia or a normal acid-base balance in an experimental setup, which included mechanical ventilation and renal replacement therapy to facilitate biotrauma caused by extracorporeal therapies. Interestingly, extensive histomorphological changes like a tubular loss of cell barriers occurred in the kidneys after just 5 hours exposure to acidemia. The additional exposure to hypoxemia aggravated these findings. These ‘early’ microscopic pathologies opposed intra vitam data of kidney function. They did not mirror cellular or systemic patterns of proinflammatory molecules (like TNF-α or IL 18) nor were they detectable by new, sensitive markers of AKI like Neutrophil gelatinase-associated lipocalin. Instead, the data suggest that the increased renal proton excretion during acidemia could be an ‘early’ first hit in the multifactorial pathogenesis of AKI. [ABSTRACT FROM AUTHOR]

Metal-Organic Frameworks (MOFs) have attracted increasing attention for the creation of solid-state platforms for catalysis applications. In this review article, we present strategies to employ MOF-based materials in photochemical hydrogen production. The scope ranges from the incorporation of single functions (catalyst or photosensitizer) to multifunctional MOFs that combine both light-harvesting and catalysis in one scaffold. [ABSTRACT FROM AUTHOR]

Background: The ideal perioperative oxygen concentration is controversial and study results are inconsistent. Objective: Current knowledge on the beneficial and adverse effects of perioperative hyperoxia. Material and methods: Narrative review Results: Perioperative hyperoxia is unlikely to increase the incidence of atelectasis, pulmonary or cardiovascular complications or mortality. Few and small potential beneficial effects, such as reduction of surgical wound infections or postoperative nausea and vomiting have been demonstrated. According to the current state of evidence, it is recommended to avoid perioperative hyperoxia and to aim for normoxia instead. [ABSTRACT FROM AUTHOR]

A facile one-pot transformation of Dmp-I to Dmp-P=CBr2(Dmp = 2,6-dimesitylphenyl), a valuable precursor for other unsaturated phosphorus compounds, is described. VT-1H-NMR experiments reveal a hindered rotation of the m-terphenyl structure with a rotational barrier of approx. 14 kcal/mol. Bromination of Dmp-I gives selective substitution of all aromatic protons of the mesityl substituents. [ABSTRACT FROM PUBLISHER]

Implantation of a temporary percutaneous right ventricular assist device (RVAD) in patients with right heart failure after left ventricular assist device (LVAD) implantation is an established technique that may cause complications. We present a 60-year-old male patient who underwent urgent LVAD implantation. On the second postoperative day the patient developed acute right heart failure. We implanted a temporary percutaneous RVAD with two cannulas via the right internal jugular vein and the right femoral vein. Transesophageal echocardiography revealed severe pulmonary insufficiency. After performing re-sternotomy we anastomosed a prosthetic graft to the pulmonary trunk (PT), performed subxiphoid tunneling of the graft and replaced the transjugular outflow cannula. The pulmonary regurgitation caused by the percutaneous transvalvular cannula disappeared. In such case a direct anastomosis to the PT is the solution. [ABSTRACT FROM AUTHOR]

Bis(trimethylsilyl)-terminated C,C-diacetylenic phosphaalkene was prepared from Mes*PCl2and a propargylic Grignard reagent that in turn was formed from 3-bromo-1,5-bis(trimethylsilyl)penta-1,4-diyne and Rieke-Mg. [ABSTRACT FROM PUBLISHER]

The bichromophoric system Ru-Ruc-PI ([(bpy)3Ru-Ph-Ru(dpb)(Metpy-PI)][PF6]3, where bpy is 2,2′-bipyridine, Hdpb is 1,3-di(2-pyriayl)-benzene, Metpy is 4′-methyl-2,2′:6′,2″-terpyridirie and Pl is pyromellitimide) containing two Ru(lI) polypyridyl chromophores with a N6 and a N5C ligand set, respectively, was synthesized and characterized. Its photophysical properties were investigated and compared to those of the monochromophoric cyclometalated complexes Ruc-Pl ([Ru(dpb)(Metpy-Pl)][PF6]), Ruc-Pl ([Ru(dpb)(ttpy-Pl)][PF6], ttpy is 4′-p-tolyl-2,2′:6′,2″- terpyridine), Ruc-φ ([Ru(dpb)(ttpy)][PF6]), and Ruc ([Ru(dpb)(Metpy)][PF6]). Excitation of the Ruc unit in the dyads leads to oxidative quenching, forming the RucIII-φ-Pl·- and RucIII-Pl·- charge-separated (CS) states with kETf = 7.7 · 107 s-1 (CH3CN, 298 K) in the tolyl-linked Ruc-φ-Pl and kETf = 4.4 × 109 s-1 (CH2Cl2, 298 K) in the methylene-linked Ruc-Pl. In the Ru-Ruc-Pl triad, excitation of the Ruc chromophore leads to dynamics similar to those in the Ruc-Pl dyad, generating the RuII-RucIII-Pl·- CS state, whereas excitation of the Ru unit results in an initial energy transfer (kEnT = 4.7 × 1011 s-1) to the cyclometalated Ruc unit. Subsequent electron transfer to the Pl acceptor results in the formation of the same RuII-RucIII-Pl·- CS state with kETf = 5.6 × 109 s-1 that undergoes rapid recombination with kETb = 1 × 1010 s-1 (CH2Cl2, 298 K). The fate of the RuII-RucIII-Pl·- CS state upon a second photoexcitation was studied by pump-pump-probe experiments in an attempt to detect the fully charge-separated RuII-RucII-Pl·- state. [ABSTRACT FROM AUTHOR]

A model of the iron hydrogenase active site with the structure [µ-ADT)Fe2(CO)6] (ADT= azadithiolate (S-CH2NR-CH2-S), (2: R = 4-bromophenyl, 3: R = 4-iodophenyl)) has been assembled and covalently linked to a [Ru(terpy)2]2+ photosensitizer. This trinuclear complex 1 represents one synthetic step toward the realization of our concept of light-driven proton reduction. A rigid phenylacetylene tether has been incorporated as the linking unit in 1 in order to prolong the lifetime of the otherwise short-lived [Ru(terpy)2]2+ excited state. The success of this strategy is demonstrated by comparison of the photophysical properties of 1 and of two related ruthenium complexes bearing acetylenic terpyridine ligands, with those of [Ru(terpy)2]2+. IR and electrochemical studies reveal that the nitrogen heteroatom of the ADT bridge has a marked influence on the electronic properties of the [Fe2(CO)6] core. Using the Rehm-Weller equation, the driving force for an electron transfer from the photoexcited *[Ru(terpy)2]2+ to the diiron site in 1 was calculated to be uphill by 0.59 eV. During the construction of the trinuclear complex 1, n-propylamine has been identified as a decarbonylation agent on the [µ-ADT)Fe2(CO)6] portion of the supermolecule. Following this procedure, the first azadithiolate-bridged dinuclear iron complex coordinated by a phosphine ligand [(µ-ADT)Fe2(CO)5PPh3] (4, R = 4-bromophenyl) was synthesized. [ABSTRACT FROM AUTHOR]

Background: A better understanding of the pancreatic ductal adenocarcinoma (PDAC) immune microenvironment is critical to developing new treatments and improving outcomes. Myeloid cells are of particular importance for PDAC progression; however, the presence of heterogenous subsets with different ontogeny and impact, along with some fluidity between them, (infiltrating monocytes vs. tissue‐resident macrophages; M1 vs. M2) makes characterisation of myeloid populations challenging. Recent advances in single cell sequencing technology provide tools for characterisation of immune cell infiltrates, and open chromatin provides source and function data for myeloid cells to assist in more comprehensive characterisation. Thus, we explore single nuclear assay for transposase accessible chromatin (ATAC) sequencing (snATAC‐Seq), a method to analyse open gene promoters and transcription factor binding, as an important means for discerning the myeloid composition in human PDAC tumours. Methods: Frozen pancreatic tissues (benign or PDAC) were prepared for snATAC‐Seq using 10× Chromium technology. Signac was used for preliminary analysis, clustering and differentially accessible chromatin region identification. The genes annotated in promoter regions were used for Gene Ontology (GO) enrichment and cell type annotation. Gene signatures were used for survival analysis with The Cancer Genome Atlas (TCGA)‐pancreatic adenocarcinoma (PAAD) dataset. Results: Myeloid cell transcription factor activities were higher in tumour than benign pancreatic samples, enabling us to further stratify tumour myeloid populations. Subcluster analysis revealed eight distinct myeloid populations. GO enrichment demonstrated unique functions for myeloid populations, including interleukin‐1b signalling (recruited monocytes) and intracellular protein transport (dendritic cells). The identified gene signature for dendritic cells influenced survival (hazard ratio =.63, p =.03) in the TCGA‐PAAD dataset, which was unique to PDAC. Conclusions: These data suggest snATAC‐Seq as a method for analysis of frozen human pancreatic tissues to distinguish myeloid populations. An improved understanding of myeloid cell heterogeneity and function is important for developing new treatment targets in PDAC. [ABSTRACT FROM AUTHOR]

Recent studies have established that the circadian clock influences onset, progression and therapeutic outcomes in a number of diseases including cancer and heart diseases. Therefore, there is a need for tools to measure the functional state of the molecular circadian clock and its downstream targets in patients. Moreover, the clock is a multi-dimensional stochastic oscillator and there are few tools for analysing it as a noisy multigene dynamical system. In this paper we consider the methodology behind TimeTeller, a machine learning tool that analyses the clock as a noisy multigene dynamical system and aims to estimate circadian clock function from a single transcriptome by modelling the multi-dimensional state of the clock. We demonstrate its potential for clock systems assessment by applying it to mouse, baboon and human microarray and RNA-seq data and show how to visualise and quantify the global structure of the clock, quantitatively stratify individual transcriptomic samples by clock dysfunction and globally compare clocks across individuals, conditions and tissues thus highlighting its potential relevance for advancing circadian medicine. Author summary: The cellular circadian clock consists of an interacting set of genes that through their interactions oscillate throughout the day. This oscillator also responds to external cues so that the genes oscillate in phase with external environmental rhythms. A cell therefore uses its circadian clock to provide its genes with information about the external time. In this way it can coordinate many of the processes taking place in the cell and allocate some of these processes to specific times of the day. It is becoming increasingly clear that the quality of this timing information influences onset progression and outcome in a number of chronic diseases such as cancer. Our aim is therefore to develop a machine-learning tool that can assess how well the clock is working. We want to use this with patients and therefore, for clinical utility, it needs to work with only a single clinical sample and to produce reproducible results that can be clearly interpreted and easily compared. [ABSTRACT FROM AUTHOR]

Photoelectrochemical CO2 reduction is a promising approach for renewable fuel generation and to reduce greenhouse gas emissions. Owing to their synthetic tunability, molecular catalysts for the CO2 reduction reaction can give rise to high product selectivity. In this context, a RuII complex [Ru(HO-tpy)(6-mbpy)(NCCH3)]2+ (HO-tpy = 4′-hydroxy-2,2′:6′,2′′-terpyridine; 6-mbpy = 6-methyl-2,2′-bipyridine) was immobilised on a thin SiOx layer of a p-Si electrode that was decorated with a bromide-terminated molecular layer. Following the characterisation of the assembled photocathodes by X-ray photoelectron spectroscopy and ellipsometry, PEC experiments demonstrate electron transfer from the p-Si to the Ru complex through the native oxide layer under illumination and a cathodic bias. A state-of-the-art photovoltage of 570 mV was determined by comparison with an analogous n-type Si assembly. While the photovoltage of the modified photocathode is promising for future photoelectrochemical CO2 reduction and the p-Si/SiOx junction seems to be unchanged during the PEC experiments, a fast desorption of the molecular Ru complex was observed. An in-depth investigation of the cathode degradation by comparison with reference materials highlights the role of the hydroxyl functionality of the Ru complex to ensure its grafting on the substrate. In contrast, no essential role for the bromide function on the Si substrate designed to engage with the hydroxyl group of the Ru complex in an SN2-type reaction could be established. [ABSTRACT FROM AUTHOR]

Background: Recent data from the randomized SUSTAIN CSX trial could not confirm clinical benefits from perioperative selenium treatment in high-risk cardiac surgery patients. Underlying reasons may involve inadequate biosynthesis of glutathione peroxidase (GPx3), which is a key mediator of selenium's antioxidant effects. This secondary analysis aimed to identify patients with an increase in GPx3 activity following selenium treatment. We hypothesize that these responders might benefit from perioperative selenium treatment. Methods: Patients were selected based on the availability of selenium biomarker information. Four subgroups were defined according to the patient's baseline status, including those with normal kidney function, reduced kidney function, selenium deficiency, and submaximal GPx3 activity. Results: Two hundred and forty-four patients were included in this analysis. Overall, higher serum concentrations of selenium, selenoprotein P (SELENOP) and GPx3 were correlated with less organ injury. GPx3 activity at baseline was predictive of 6-month survival (AUC 0.73; p = 0.03). While selenium treatment elevated serum selenium and SELENOP concentrations but not GPx3 activity in the full patient cohort, subgroup analyses revealed that GPx3 activity increased in patients with reduced kidney function, selenium deficiency and low to moderate GPx3 activity. Clinical outcomes did not vary between selenium treatment and placebo in any of these subgroups, though the study was not powered to conclusively detect differences in outcomes. Conclusions: The identification of GPx3 responders encourages further refined investigations into the treatment effects of selenium in high-risk cardiac surgery patients. [ABSTRACT FROM AUTHOR]

The Society for Cardiovascular Angiography and Interventions (SCAI) shock classification has been shown to provide robust mortality risk stratification in a variety of cardiovascular patients. This study sought to evaluate the SCAI shock classification in postoperative cardiac surgery intensive care unit (CSICU) patients. This study retrospectively analyzed 26,792 postoperative CSICU admissions at a heart center between 2012 and 2022. Patients were classified into SCAI shock stages A to E using electronic health record data. Moreover, the impact of late deterioration (LD) as an additional risk modifier was investigated. The proportions of patients in SCAI shock stages A to E were 24.4%, 18.8%, 8.4%, 35.5%, and 12.9%, and crude hospital mortality rates were 0.4%, 0.6%, 3.3%, 4.9%, and 30.2%, respectively. Similarly, the prevalence of postoperative complications and organ dysfunction increased across SCAI shock stages. After multivariable adjustment, each higher SCAI shock stage was associated with increased hospital mortality (adjusted OR: 1.26-16.59) compared with SCAI shock stage A, as was LD (adjusted OR: 8.2). The SCAI shock classification demonstrated a strong diagnostic performance for hospital mortality (area under the receiver operating characteristic: 0.84), which noticeably increased when LD was incorporated into the model (area under the receiver operating characteristic: 0.90). The SCAI shock classification effectively risk-stratifies postoperative CSICU patients for mortality, postoperative complications, and organ dysfunction. Its application could, therefore, be extended to the field of cardiac surgery as a triage tool in postoperative care and as a selection criterion in research. [Display omitted] [ABSTRACT FROM AUTHOR]

Photochemical hydrogen evolution from a UiO‐66‐incorporated Fe2(dcbdt)(CO)6 catalyst in conjunction with a ruthenium photosensitizer and an ascorbate donor ceases after a period of irradiation, but is restored after a 60 min. resting period in the dark. Control experiments show that neither product inhibition nor pore clogging is responsible for this surprising behaviour, and intra‐crystal linker scrambling is proposed as a potential explanation. [ABSTRACT FROM AUTHOR]

Water is known to play an important role for the crystallization and stability of Zr‐based metal‐organic frameworks (MOFs). This work investigates its effect on the vapor‐assisted conversion (VAC) synthesis of UiO‐67 MOF thin films on Au‐coated Si substrates. We demonstrate the equilibration processes taking place during the VAC procedure, confirming the gradual equilibration of all solutions upon heating. The presence of water affects the vapor phase composition but does not significantly impact the acetic acid equilibration rate. However, the preparation of UiO‐67 thin films by VAC is highly sensitive to the water content in the reaction. Some water is required for the formation of the zirconium clusters, but excessive water in the reaction vial yields poorly crystalline materials. Atmospheric water that is taken up by the vapor source can be sufficient to reduce crystallinity dramatically. This complication can be partially overcome by increasing the amount of acetic acid in the vapor source. [ABSTRACT FROM AUTHOR]

PhP(Li)TMS converts benzophenones to phosphaalkenes which upon activation under oxidizing, basic conditions react with aromatic aldehydes under the formation of triarylalkenes. The one-pot reaction omits transition metals, proceeds at room temperature and precludes the formation of any homo-coupling products. Systematic substrate variations reveal reactivity patterns that are useful for the identification of ketone/aldehyde combinations that can be coupled in yields up to 80%. [ABSTRACT FROM AUTHOR]

Biphenyl-4,4′-dicarboxylic acid derivatives containing either azide or acetylene functional groups were inserted into UiO-67 metal organic frameworks (MOFs) via post synthetic linker exchange. Sequential and orthogonal click reactions could be performed on these modified MOFs by incubating the crystals with small molecule substrates bearing azide or acetylene groups in the presence of a copper catalyst. 1H NMR of digested MOF samples showed that up to 50% of the incorporated linkers could be converted to their “clicked” triazole products. Powder X-ray diffraction confirmed that the UiO-67 structure was maintained throughout all transformations. The click reaction efficiency is discussed in context of MOF crystallite size and pore size. As the incorporation of clicked linkers could be controlled by post synthetic exchange, this work introduces a powerful method of quickly introducing orthogonal modifications into known MOF architectures. [ABSTRACT FROM AUTHOR]

The article discusses a study within the issue regarding chemistry research by Boddien and colleagues who report a molecular iron complex that catalyzes hydrogen (H2) formation from formic acid (HCOOH) at both high rates and multiple catalytic cycles. Topics include the challenges of the large-scale use of H2 as a transportation fuel and Boddien and colleagues' research methodology for finding a catalyst for the dehydrogenation of HCOOH in solution. Also discussed are the results of spectroscopic studies and density functional theory calculations that suggest two viable pathways for H2 release from HCOOH using a common iron (Fe)-hydride species, [FeH(PP3)]+, instead of a noble metal, such as rhodium.

A bis-[W(CO)5]-coordinated (tBu)2diphosphene was prepared from the corresponding [W(CO)5]-tBuPCl2 by treatment with LiAlH4. [ABSTRACT FROM AUTHOR]

The title compound, (μ-(SCH2)2CH2)Fe(CO)3Fe(CO)2P(C6H5)2NHCH2CH2CH3, has been prepared and characterized as a a model substance for a class of enzymes known as hydrogenases. [ABSTRACT FROM AUTHOR]

The synthesis of a novel monomeric precursor and its butadiyne‐bridged dimeric form for the preparation of novel π‐conjugated organophosphorus compounds is presented. The precursors are synthesized from commercially available starting materials, and based on a Dmp (2,6‐dimesitylphenyl) group for kinetic stabilization of the P‐functionality, a bromo substituent for the introduction of the phosphorus center, and an acetylene unit at the para position of the Dmp moiety. Such acetylenic units are synthetically versatile, and can be explored for the construction of larger phosphorus‐containing π‐conjugates. The precursors are utilized to prepare Dmp‐stabilized C,C‐dibromophosphaalkenes, and butadiyne‐bridged dimeric species thereof. The effect of the low‐coordinate phosphorus centers and the extent of π‐conjugation on the spectroscopic and electronic properties is evaluated by NMR and UV/Vis spectroscopy, as well as cyclic voltammetry. In addition to the phosphaalkenes, the successful syntheses of two new diphosphenes are presented, indicating a broad applicability of the precursor. [ABSTRACT FROM AUTHOR]

The modularity and synthetic flexibility of metal–organic frameworks (MOFs) have provoked analogies with enzymes, and even the term MOFzymes has been coined. In this review, we focus on molecular catalysis of energy relevance in MOFs, more specifically water oxidation, oxygen and carbon dioxide reduction, as well as hydrogen evolution in context of the MOF–enzyme analogy. Similar to enzymes, catalyst encapsulation in MOFs leads to structural stabilization under turnover conditions, while catalyst motifs that are synthetically out of reach in a homogeneous solution phase may be attainable as secondary building units in MOFs. Exploring the unique synthetic possibilities in MOFs, specific groups in the second and third coordination sphere around the catalytic active site have been incorporated to facilitate catalysis. A key difference between enzymes and MOFs is the fact that active site concentrations in the latter are often considerably higher, leading to charge and mass transport limitations in MOFs that are more severe than those in enzymes. High catalyst concentrations also put a limit on the distance between catalysts, and thus the available space for higher coordination sphere engineering. As transport is important for MOF-borne catalysis, a system perspective is chosen to highlight concepts that address the issue. A detailed section on transport and light-driven reactivity sets the stage for a concise review of the currently available literature on utilizing principles from Nature and system design for the preparation of catalytic MOF-based materials. [ABSTRACT FROM AUTHOR]

Impella 5.0 and 5.5 (summarized as Impella 5+) are microaxial, catheter-based left ventricular assist devices (LVAD) that are implanted via a vascular graft sutured to the axillary artery and provide blood flow of up to 5.5 liter/min. This study aims to investigate the incidence of long-term complications following circulatory support with Impella 5+. A single-center retrospective analysis of 203 consecutive adult patients treated between January 2017 and September 2021 with a surgically implanted Impella 5.0 or 5.5 via a vascular graft sutured to the axillary artery. The median Impella support duration was 8 days. Of 203 patients, 78 (38.4%) died while on temporary mechanical circulatory support. Fifty-five (27.1%) were successfully weaned from Impella 5+ and 70 (34.5%) were bridged to a durable LVAD with a median follow-up time of 232 (IQR 68.5, 597) days after Impella 5+ explantation. In 119 of these patients, the Impella was explanted and the vascular graft was shortened, ligated, and pushed under the pectoralis muscle; in 6 patients early graft infection prompted complete graft removal during explantation. In addition, 13 patients (10.9%) developed a late-onset graft infection after a median of 86 days, requiring complete (n = 10) or partial (n = 2) explantation of the retained graft. In 1 patient, the graft infection was successfully treated by conservative therapy. Our analysis identified no specific risk factors for graft infections. Of the 203 patients, 5 (2.5%) developed a brachial plexus injury resulting in neurological dysfunction. In 10.9% of patients, retaining the vascular graft was complicated by a late graft infection. Complete explantation of the graft prosthesis may decrease the infection rate, but may in turn increase the risk of brachial plexus injury. On the other hand, this method offers the possibility of bedside explantation. [ABSTRACT FROM AUTHOR]

Molecular electrocatalysts for CO2‐to‐CO conversion often operate at large overpotentials, due to the large barrier for C−O bond cleavage. Illustrated with ruthenium polypyridyl catalysts, we herein propose a mechanistic route that involves one metal center that acts as both Lewis base and Lewis acid at different stages of the catalytic cycle, by density functional theory in corroboration with experimental FTIR. The nucleophilic character of the Ru center manifests itself in the initial attack on CO2 to form [Ru‐CO2]0, while its electrophilic character allows for the formation of a 5‐membered metallacyclic intermediate, [Ru‐CO2CO2]0,c, by addition of a second CO2 molecule and intramolecular cyclization. The calculated activation barrier for C−O bond cleavage via the metallacycle is decreased by 34.9 kcal mol−1 as compared to the non‐cyclic adduct in the two electron reduced state of complex 1. Such metallacyclic intermediates in electrocatalytic CO2 reduction offer a new design feature that can be implemented consciously in future catalyst designs. [ABSTRACT FROM AUTHOR]

Molecular electrocatalysts for CO2‐to‐CO conversion often operate at large overpotentials, due to the large barrier for C−O bond cleavage. Illustrated with ruthenium polypyridyl catalysts, we herein propose a mechanistic route that involves one metal center that acts as both Lewis base and Lewis acid at different stages of the catalytic cycle, by density functional theory in corroboration with experimental FTIR. The nucleophilic character of the Ru center manifests itself in the initial attack on CO2 to form [Ru‐CO2]0, while its electrophilic character allows for the formation of a 5‐membered metallacyclic intermediate, [Ru‐CO2CO2]0,c, by addition of a second CO2 molecule and intramolecular cyclization. The calculated activation barrier for C−O bond cleavage via the metallacycle is decreased by 34.9 kcal mol−1 as compared to the non‐cyclic adduct in the two electron reduced state of complex 1. Such metallacyclic intermediates in electrocatalytic CO2 reduction offer a new design feature that can be implemented consciously in future catalyst designs. [ABSTRACT FROM AUTHOR]

Metal -- organic frameworks (MOFs) as electro-catalysis scaffolds are appealing due to the large concentration of catalytic units that can be assembled in three dimensions. To harness the full potential of these materials, charge transport to the redox catalysts within the MOF has to be ensured. Herein, we report the first electroactive MOF with the UiO/PIZOF topology (Zr(dcphOH-NDI)), i.e., one of the most widely used MOFs for catalyst incorporation, by using redox-active naphthalene diimide-based linkers (dcphOH-NDI). Hydroxyl groups were included on the dcphOH-NDI linker to facilitate proton transport through the material. Potentiometric titrations of Zr(dcphOH-NDI) show the proton-responsive behavior via the -- OH groups on the linkers and the bridging Zr-μ3-OH of the secondary building units with pKa values of 6.10 and 3.45, respectively. When grown directly onto transparent conductive fluorine-doped tin oxide (FTO), 1 μm thin films of Zr(dcphOH-NDI)@FTO could be achieved. Zr(dcphOH-NDI)@FTO displays reversible electrochromic behavior as a result of the sequential one-electron reductions of the redox-active NDI linkers. Importantly, 97% of the NDI sites are electrochemically active at applied potentials. Charge propagation through the thin film proceeds through a linker-to-linker hopping mechanism that is charge-balanced by electrolyte transport, giving rise to cyclic voltammograms of the thin films that show characteristics of a diffusion-controlled process. The equivalent diflusion coefficient, De, that contains contributions from both phenomena was measured directly by UV/vis spectroelectrochemistry. Using KPF6 as electrolyte, De was determined to be De(KPF6) = (5.4 ± 1.1) × 10[sup -11] cm[sup 2] s[sup -1], while an increase in countercation size to n-Bu4N[sup +] led to a significant decrease of De by about 1 order of magnitude (De(n-Bu4NPF6) = (4.0 ± 2.5) × 10[sup -12] cm[sup 2] s[sup -1]). [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article, which discusses the application of market forces to peer review that was published in January 2014 issue.

The first examples of a π‐conjugated benzo[b]phosphole P‐oxide in which two phosphole P‐oxide units are connected by a carbon‐carbon double bond are described. The molecules are synthesized as E isomers with respect to the carbon‐carbon double bond and exist as stable cis and trans isomers (chiral and meso one respectively) relatively to the two stereogenic P atoms. The optical and electrochemical properties of both isomers have been investigated by experiment and computations. [ABSTRACT FROM AUTHOR]

The reactivity of [Fe2(dcbdt)(CO)6] (1) confined in a UiO-66(Zr) metal–organic framework towards CO ligand substitutions with phosphines of different sizes was investigated. The reaction with smaller phosphines (PX3, X = Me, Et) is more selective compared to analogous reactions in homogenous solution phase, and two CO ligands at up to 80% of all [FeFe] sites in UiO-66–1 are replaced. The produced [Fe2(dcbdt)(CO)4(PX3)2] complexes in the UiO-66 matrix behave like typical [FeFe] hydrogenase active site model complexes, are reduced at more cathodic potentials than their hexacarbonyl analogues, and form bridging hydrides under acidic conditions. [ABSTRACT FROM AUTHOR]

The unprecedented formation of unsymmetrical alkenes from the intermolecular reductive coupling of two different aldehydes is described. In contrast to the McMurry reaction which affords statistical product mixtures, selectivity in the reported procedure is achieved by a sequential ionic mechanism in which a first aldehyde is reacted with a phosphanylphosphonate to afford a phosphaalkene intermediate which, upon activation by hydroxide, reacts with a second aldehyde to the unsymmetrical E-alkenes. The described reaction is free of transition metals and proceeds under ambient temperature within minutes in good to excellent overall yields. It is a new methodology to use feedstock aldehydes for the direct production of C=C double bond-containing products and may impact how chemists think of multistep synthetic sequences in the future. [ABSTRACT FROM AUTHOR]

A molecular water oxidation catalyst, [Ru(tpy)(dcbpy)(OH2)](ClO4)2 (tpy = 2,2′:6′,2′′-terpyridine, dcbpy = 2,2′-bipyridine-5,5′-dicarboxylic acid) [1], has been incorporated into FTO-grown thin films of UiO-67 (UiO = University of Oslo), by post-synthetic ligand exchange. Cyclic voltammograms (0.1 M borate buffer at pH = 8.4) of the resulting UiO67-[RuOH2]@FTO show a reversible wave associated with the RuIII/II couple in the anodic scan, followed by a large current response that arises from electrocatalytic water oxidation beyond 1.1 V vs. Ag/AgCl. Water oxidation can be observed at an applied potential of 1.5 V over the timescale of hours with a current density of 11.5 μA cm−2. Oxygen evolution was quantified in situ over the course of the experiment, and the Faradaic efficiency was calculated as 82%. Importantly, the molecular integrity of [1] during electrocatalytic water oxidation is maintained even on the timescale of hours under turnover conditions and applied voltage, as evidenced by the persistence of the wave associated with the RuIII/II couple in the CV. This experiment highlights the capability of metal organic frameworks like UiO-67 to stabilize the molecular structure of catalysts that are prone to form higher clusters in homogenous phase. [ABSTRACT FROM AUTHOR]

The battery system is a main driver of current reservations against electrical vehicles, because it influences aspects like vehicle range, charging time and costs. Further the battery system is highly connected to the surrounding subsystems of the vehicle. Hence, developing battery systems means to deal with manifold interconnectivities. Within this, sufficient and transparent objectives for the battery system have to be defined. This work presents a systematic approach to defining objectives for the battery system down to the behavior of battery cells by considering the drive system in relevant use cases. Three investigations on the complexity of developing battery systems are done: Interviews with engineers to investigate the challenges of developing battery systems, parameter variation in a vehicle simulation model to analyze the influences of the surrounding systems and analysis of the theoretical interdependencies between battery system, power electronics and electric drive. The findings in combination with the literature research lead to requirements to be met by the approach. In addition to the battery system the configuration of the drive system should be considered as well as different customer relevant use cases. An approach to defining objectives for battery systems based on a parameter variation is introduced and it is explained how concrete objectives can be derived from customer perceptions in a transparent way. [ABSTRACT FROM AUTHOR]

The battery system is a main driver of current reservations against electrical vehicles, because it influences aspects like vehicle range, charging time and costs. Further the battery system is highly connected to the surrounding subsystems of the vehicle. Hence, developing battery systems means to deal with manifold interconnectivities. Within this, sufficient and transparent objectives for the battery system have to be defined. This work presents a systematic approach to defining objectives for the battery system down to the behavior of battery cells by considering the drive system in relevant use cases. Three investigations on the complexity of developing battery systems are done: Interviews with engineers to investigate the challenges of developing battery systems, parameter variation in a vehicle simulation model to analyze the influences of the surrounding systems and analysis of the theoretical interdependencies between battery system, power electronics and electric drive. The findings in combination with the literature research lead to requirements to be met by the approach. In addition to the battery system the configuration of the drive system should be considered as well as different customer relevant use cases. An approach to defining objectives for battery systems based on a parameter variation is introduced and it is explained how concrete objectives can be derived from customer perceptions in a transparent way. [ABSTRACT FROM AUTHOR]

Solar conversion of water into the storable energy carrier H2 can be achieved through photoelectrochemical water splitting using light adsorbing anodes and cathodes bearing O2 and H2 evolving catalysts, respectively. Herein a novel photocathode nanohybrid system is reported. This photocathode consists of a dye-sensitized p-type nickel oxide (NiO) with a perylene-based chromophore (PCA) and a tetra-adamantane modified cobaloxime reduction catalyst (Co) that photo-reduces aqueous protons to H2. An original supramolecular approach was employed, using β-cyclodextrin functionalized gold nanoparticles (β-CD-AuNPs) to link the alkane chain of the PCA dye to the adamantane moieties of the cobaloxime catalyst (Co). This new architecture was investigated by photoelectrochemical measurements and via femtosecond-transient absorption spectroscopy. The results show that irradiation of the complete NiO‖PCA‖β-CD-AuNPs‖Co electrode leads to ultrafast hole injection into NiO (π = 3 ps) from the excited dye, followed by rapid reduction of the catalyst, and finally H2 evolution. [ABSTRACT FROM AUTHOR]

Current methodologies for the direct reductive coupling of two aldehydes to alkenes afford almost exclusively the thermodynamically favoured E‐isomer. Recent efforts to find phosphorus‐based reagents as replacements for the low‐valent Ti species in McMurry couplings present opportunities to change this shortcoming, and to design new reagents that allow for the formation of high proportions of Z‐alkenes under kinetic control. Here, we report the first example of such a reagent, a phosphanyl phosphonate MesFP(H)P(O)(OEt)2, 6, with an electron‐deficient MesF=2,4,6‐(CF3)3Ph substituent that promotes the reductive homo‐coupling of (hetero)aromatic aldehydes to alkenes with high Z‐selectivity. Computational results indicate that the selectivity stems from the electron deficient MesF, which results in lowered activation barriers for the collapse of a cis‐oxaphosphetane intermediate. In the absence of MesF, the E‐isomer is exclusively observed experimentally. Directing the isomeric outcome of alkene formation by introducing electron withdrawing P‐substituents bears resemblance to the Still‐Gennari modification of the Horner‐Wadsworth‐Emmons reaction where perfluorinated ethoxy substituents in the former also lead to high proportions of the Z‐isomer. [ABSTRACT FROM AUTHOR]

Versatile synthetic protocols for 2,7- and 3,6-diacetylenic fluorene-9-ylidene phosphanes (F9Ps) were developed. Protodesilylation of trimethylsilyl-protected acetylenic F9Ps affords terminal acetylenes that can be employed in Sonogashira and Glaser-type C−C coupling reactions to give thienyl-decorated and butadiyne-bridged fluorene-9-ylidene phosphanes, respectively. As evidenced by UV/Vis spectroscopy and cyclic voltammetry and corroborated by ab initio calculations, the presence of the P center in the F9Ps induces a significantly reduced HOMO-LUMO splitting that originates from stabilization of the LUMO levels. Variation of the acetylene substitution pattern is an additional tool to influence the optical and electronic properties. Whereas 3,6-disubstituted F9Ps have strong absorptions around 400 nm, mainly due to π-π* transitions, 2,7-diacetylenic F9Ps exhibit longest-wavelength absorptions that have significant charge-transfer character with an onset around 520 nm. [ABSTRACT FROM AUTHOR]

A mononuclear cobalt(ii) complex as a homogeneous molecular catalyst for photochemically, electrochemically and chemically induced oxygen evolution reactions is presented. Experimental evidence points towards the presence of a chloride ligand at the cobalt centre throughout the catalytic cycle, and the temporary detachment of a pyridine ligand to open a coordination site for substrate binding. [ABSTRACT FROM AUTHOR]

Background: Cardiopulmonary bypass (CPB) during left ventricular assist device (LVAD) implantation provides circulatory support and allows for safe inspection of the left ventricle (LV), whereas circulatory support by veno‐arterial extracorporeal life support (va‐ECLS) or off‐pump implantation may reduce postoperative bleeding and inflammatory response. Methods: Retrospective analysis of 616 consecutive adult patients who received an LVAD via median sternotomy between January 1, 2015 and December 31, 2019. All patients undergoing concomitant intracardiac procedures other than closure of persistent foramen ovale or atrial septal defect and redo surgeries were excluded from the analysis. The remaining patients (n = 222) were divided into two groups and 1:1 propensity score‐matched regarding preoperative parameters: patients who underwent LVAD implantation with LV inspection employing CPB (CPB group, n = 62) and without LV inspection on va‐ECLS or off‐pump (non‐CPB group, n = 62). Results: The groups were well balanced with regard to preoperative baseline characteristics (standard difference <0.1). Patients in the CPB group required more blood transfusions (median 2 vs. 0 units, p = 0.031) during surgery and in the first 24 h afterwards. The median intensive care unit stay was longer in the CPB group (18 vs. 11 days, p = 0.021). The CPB group showed an absence of perioperative stroke and a smaller number of events per patient‐year for postoperative ischemic stroke (0.02 vs. 0.12, p = 0.003). 30‐day survival (87% vs. 87.1%) and 1‐year survival (80.3% vs. 74%) were similar in both groups (p = 0.78). Conclusion: Visual LV inspection on CPB may reduce the risk of postoperative ischemic stroke. Despite the negative effects of employing CPB in lieu of other intraoperative strategies, survival was similar in both groups. [ABSTRACT FROM AUTHOR]

Legumes house nitrogen-fixing endosymbiotic rhizobia in specialized polyploid cells within root nodules, which undergo tightly regulated metabolic activity. By carrying out expression analysis of transcripts over time in Medicago truncatula nodules, we found that the circadian clock enables coordinated control of metabolic and regulatory processes linked to nitrogen fixation. This involves the circadian clock-associated transcription factor LATE ELONGATED HYPOCOTYL (LHY), with lhy mutants being affected in nodulation. Rhythmic transcripts in root nodules include a subset of nodule-specific cysteine-rich peptides (NCRs) that have the LHY-bound conserved evening element in their promoters. Until now, studies have suggested that NCRs act to regulate bacteroid differentiation and keep the rhizobial population in check. However, these conclusions came from the study of a few members of this very large gene family that has complex diversified spatio-temporal expression. We suggest that rhythmic expression of NCRs may be important for temporal coordination of bacterial activity with the rhythms of the plant host, in order to ensure optimal symbiosis. [ABSTRACT FROM AUTHOR]

Study Question: Can the accuracy of timing of luteal phase endometrial biopsies based on urinary ovulation testing be improved by measuring the expression of a small number of genes and a continuous, non-categorical modelling approach?Summary Answer: Measuring the expression levels of six genes (IL2RB, IGFBP1, CXCL14, DPP4, GPX3 and SLC15A2) is sufficient to obtain substantially more accurate timing estimates and to assess the reliability of timing estimates for each sample.What Is Known Already: Commercially available endometrial timing approaches based on gene expression require large gene sets and use a categorical approach that classifies samples as pre-receptive, receptive or post-receptive.Study Design, Size, Duration: Gene expression was measured by RTq-PCR in different sample sets, comprising a total of 664 endometrial biopsies obtained 4-12 days after a self-reported positive home ovulation test. A further 36 endometrial samples were profiled by RTq-PCR as well as RNA-sequencing.Participants/materials, Setting, Methods: A computational procedure, named 'EndoTime', was established that models the temporal profile of each gene and estimates the timing of each sample. Iterating these steps, temporal profiles are gradually refined as sample timings are being updated, and confidence in timing estimates is increased. After convergence, the method reports updated timing estimates for each sample while preserving the overall distribution of time points.Main Results and the Role Of Chance: The Wilcoxon rank-sum test was used to confirm that ordering samples by EndoTime estimates yields sharper temporal expression profiles for held-out genes (not used when determining sample timings) than ordering the same expression values by patient-reported times (GPX3: P < 0.005; CXCL14: P < 2.7e-6; DPP4: P < 3.7e-13). Pearson correlation between EndoTime estimates for the same sample set but based on RTq-PCR or RNA-sequencing data showed a high degree of congruency between the two (P = 8.6e-10, R2 = 0.687). Estimated timings did not differ significantly between control subjects and patients with recurrent pregnancy loss or recurrent implantation failure (P > 0.05).Large Scale Data: The RTq-PCR data files are available via the GitHub repository for the EndoTime software at https://github.com/AE-Mitchell/EndoTime, as is the code used for pre-processing of RTq-PCR data. The RNA-sequencing data are available on GEO (accession GSE180485).Limitations, Reasons For Caution: Timing estimates are informed by glandular gene expression and will only represent the temporal state of other endometrial cell types if in synchrony with the epithelium. Methods that estimate the day of ovulation are still required as these data are essential inputs in our method. Our approach, in its current iteration, performs batch correction such that larger sample batches impart greater accuracy to timing estimations. In theory, our method requires endometrial samples obtained at different days in the luteal phase. In practice, however, this is not a concern as timings based on urinary ovulation testing are associated with a sufficient level of noise to ensure that a variety of time points will be sampled.Wider Implications Of the Findings: Our method is the first to assay the temporal state of luteal-phase endometrial samples on a continuous domain. It is freely available with fully shared data and open-source software. EndoTime enables accurate temporal profiling of any gene in luteal endometrial samples for a wide range of research applications and, potentially, clinical use.Study Funding/competing Interest(s): This study was supported by a Wellcome Trust Investigator Award (Grant/Award Number: 212233/Z/18/Z) and the Tommy's National Miscarriage Research Centre. None of the authors have any competing interests. J.L. was funded by the Biotechnology and Biological Sciences Research Council (UK) through the Midlands Integrative Biology Training Partnership (MIBTP, BB/M01116X/1). [ABSTRACT FROM AUTHOR]

λ3-phosphahexatrienes were prepared from ethoxyvinyl phosphinophosphonates using the phospha-Wittig–Horner reaction. The title compounds can be easily prepared in three steps starting from dichlorophosphines with good overall yields. Although these were found to be thermally unstable, these can be trapped, for instance, with methanol. The resulting methoxyphosphines are isolated in high yields in case of aldehyde starting materials with more bulky substituents. [ABSTRACT FROM PUBLISHER]

Metal hydrides are key intermediates in the catalytic reduction of protons and CO2 as well as in the oxidation of H2. In these reactions, electrons and protons are transferred to or from separate acceptors or donors in bidirectional proton-coupled electron transfer (PCET) steps. The mechanistic interpretation of PCET reactions of metal hydrides has focused on the stepwise transfer of electrons and protons. A concerted transfer may, however, occur with a lower reaction barrier and therefore proceed at higher catalytic rates. Here we investigate the feasibility of such a reaction by studying the oxidation-deprotonation reactions of a tungsten hydride complex. The rate dependence on the driving force for both electron transfer and proton transfer-employing different combinations of oxidants and bases-was used to establish experimentally the concerted, bidirectional PCET of a metal-hydride species. Consideration of the findings presented here in future catalyst designs may lead to more-efficient catalysts. [ABSTRACT FROM AUTHOR]

The dinuclear Co complex [(TPA)Co(μ-OH)(μ-O2)Co(TPA)](ClO4)3 ( 1, TPA=tris(2-pyridylmethyl)amine) catalyzes the oxidation of water. In the presence of [Ru(bpy)3]2+ and S2O82−, photoinduced oxygen evolution can be observed with a turnover frequency (TOF) of 1.4±0.1 mol(O2) mol( 1)−1 s−1 and a maximal turnover number (TON) of 58±5 mol(O2) mol( 1)−1. The complex is shown to act as a molecular and homogeneous catalyst and a mechanism is proposed based on the combination of EPR data and light-driven O2 evolution kinetics. [ABSTRACT FROM AUTHOR]

The dinuclear Co complex [(TPA)Co(μ-OH)(μ-O2)Co(TPA)](ClO4)3 ( 1, TPA=tris(2-pyridylmethyl)amine) catalyzes the oxidation of water. In the presence of [Ru(bpy)3]2+ and S2O82−, photoinduced oxygen evolution can be observed with a turnover frequency (TOF) of 1.4±0.1 mol(O2) mol( 1)−1 s−1 and a maximal turnover number (TON) of 58±5 mol(O2) mol( 1)−1. The complex is shown to act as a molecular and homogeneous catalyst and a mechanism is proposed based on the combination of EPR data and light-driven O2 evolution kinetics. [ABSTRACT FROM AUTHOR]

A series of RuII-polypyridyl complexes of the design [RuII(tpy)(NN)X]n+ (tpy = 2,2':6',2''-terpyridine; NN = bidentate polypyridine; X = Cl- or CH3CN; n = 1 or 2) have been synthesized and analyzed for their ability to function as electrocatalysts in the reduction of CO2 to CO. Varying the electron-donating/withdrawing character of the NN polypyridyl ligand has allowed for modification of electron density at the formally RuII metal center. Complexes where X = Cl- display ligand substitution for CH3CN with differing rates of Cl- dissociation (k-Cl), therefore providing a degree of insight into the electron density and thus the chemical activity at the RuII center. Detailed analysis of the cyclic voltammograms under argon vs. CO2 atmospheres using multiple switching potentials and scan rates ranging from ν = 25-2000 mV s-1 has painted a picture of how monodentate ligand lability due to NN polypyridyl electron-donating character is related to electrocatalytic CO2 reduction activity of RuII-polypyridyl complexes. From these studies, multiple mechanistic pathways towards generating the catalytically active [Ru(tpy-)(NN-)CO2]0 species are proposed and differ via the order of electrochemical and chemical processes. [ABSTRACT FROM AUTHOR]

A biomimetic model complex of the [FeFe]-hydrogenase active site (FeFeOH) with an ethylene bridge and a pendant hydroxyl group has been synthesized, characterized and evaluated as catalyst for the light-driven hydrogen production. The interaction of the hydroxyl group present in the complex with 3-isocyanopropyltriethoxysilane provided a carbamate triethoxysilane bearing a diiron dithiolate complex (NCOFeFe), thus becoming a potentially promising candidate for anchoring on heterogeneous supports. As a proof of concept, the NCOFeFe precursor was anchored by a grafting procedure into a periodic mesoporous organosilica with ethane bridges (EthanePMO@NCOFeFe). Both molecular and heterogenized complexes were tested as catalysts for light-driven hydrogen generation in aqueous solutions. The photocatalytic conditions were optimized for the homogenous complex by varying the reaction time, pH, amount of the catalyst or photosensitizer, photon flux, and the type of light source (light-emitting diode (LED) and Xe lamp). It was shown that the molecular FeFeOH diiron complex achieved a decent turnover number (TON) of 70 after 6 h, while NCOFeFe and EthanePMO@NCOFeFe had slightly lower activities showing TONs of 37 and 5 at 6 h, respectively. [ABSTRACT FROM AUTHOR]

2,5-Di(1-naphthyl)-1-phenylphosphole ( 2) was prepared from phenylphosphine and dinaphthylbutadiyne in 70 % yield, and oxidized to its oxide 3. Treatment of 2 with a solution of potassium naphthalide results in selective formation of phospholide anion 4, which can be oxidized with iodine to afford biphosphole 5. The crystal structure of 5 exhibits an unusual s- trans conformation across the P-P bridge that is most stabilized by π-π stacking of the naphthyl substituents. Biphosphole 5 can be oxidized to its mono-oxidized 6 and dioxide 7. Generally, all phosphole oxidations lead to decreased pyramidalization of the P centres and, consequently, to significantly redshifted lowest-energy absorption maxima. Mono-oxidized biphosphole 6, which consists of an ordinary phosphole and an electron-deficient oxidized phosphole, features a unique low-energy optical transition (shoulder at 430 nm), which is tentatively assigned to a charge-transfer transition. The UV/Vis spectrum of dioxide 7 lacks this transition. At the same time, the emission maximum of 7 is bathochromically shifted by 80 nm relative to that of 5. [ABSTRACT FROM AUTHOR]