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Principles of low pressure gas electron diffraction are introduced. An experimental setup has been constructed for measuring the electron diffraction patterns of gaseous samples at pressures below 10 -3 mbar. Test measurements have been performed for benzoic acid at T = 287 K corresponding to a vapor pressure of the substance P = 2 × 10 -4 mbar, for iodoform CHI 3 at T = 288 K (P = 4 × 10 -4 mbar), and for carbon tetraiodide CI 4 at T = 290 K (P = 1 × 10 -4 mbar). Due to the low experimental temperature, thermal decomposition of CI 4 has been prevented, which was unavoidable in previous classical measurements at higher temperatures. From the obtained data, the molecular structures have been successfully refined. The most important semi-empirical equilibrium molecular parameters are r e (C ar -C ar ) av = 1.387(5) Å in benzoic acid, r e (C-I) = 2.123(3) Å in iodoform, and r e (C-I) = 2.133(7) Å in carbon tetraiodide. The determined parameters showed consistency with the theoretically predicted values. A critical comparison with the results of the earlier investigations has also been done.

We have designed and constructed a combined experimental setup for synchronous measurements of electron diffraction patterns and mass-spectra of gas samples. Test measurements have been performed for acetic acid at two temperatures, 296 K and 457 K. Electron diffraction data have been analyzed taking into account mass spectra measured in the same experiments. From the diffraction intensities, molecular structures and mole fractions of the acetic acid monomer and dimer have been refined. The obtained results demonstrate the importance of measuring mass spectra in gas electron diffraction experiments. In particular, it is possible to detect the sample decomposition, which can be used for the optimization of experimental conditions and for the data interpretation. The length of the hydrogen bond in the acetic acid dimer determined in this work, r e (O⋯H) = 1.657(9) Å, is in good agreement with modern theoretical predictions. We recommend measuring the diffraction patterns of acetic acid for the calibration of the sample pressure in the diffraction volume.

2-Arsa-1,3-butadienes (L)As(cAACR) (L = PhC[double bond, length as m-dash]C{(NDipp)CH}2, Dipp = 2,6-iPr2C6H3; cAACR = C{(NDipp)CMe2CH2C(R)}, R = Me22a, R = cyclohexyl (Cy) 2b) and the corresponding radical cations [(L)As(cAACR)]GaCl4 (R = Me23a, Cy 3b) and dications [(L)As(cAACR)](GaCl4)2 (R = Me 4a, Cy 4b) featuring a C[double bond, length as m-dash]C-As[double bond, length as m-dash]C π-conjugated framework are reported.

A synthetic strategy for the 2-phospha-1,3-butadiene derivatives [{(IPr)C(Ph)}P(cAAC Me )] ( 3a ) and [{(IPr)C(Ph)}P(cAAC Cy )] ( 3b ) (IPr = C{(NDipp)CH} 2 , Dipp = 2,6-iPr 2 C 6 H 3 ; cAAC Me = C{(NDipp)CMe 2 CH 2 CMe 2 }; cAAC Cy = C{(NDipp)CMe 2 CH 2 C(Cy)}, Cy = cyclohexyl) containing a C[double bond, length as m-dash]C-P[double bond, length as m-dash]C framework has been established. Compounds 3a and 3b have a remarkably small HOMO-LUMO energy gap ( 3a : 5.09; 3b : 5.05 eV) with a very high-lying HOMO (-4.95 eV for each). Consequently, 3a and 3b readily undergo one-electron oxidation with the mild oxidizing agent GaCl 3 to afford radical cations [{(IPr)C(Ph)}P(cAAC R )]GaCl 4 (R = Me 4a , Cy 4b ) as crystalline solids. The main UV-vis absorption band for 4a and 4b is red-shifted with respect to that of 3a and 3b , which is associated with the SOMO related transitions. The EPR spectra of compounds 4a and 4b each exhibit a doublet due to coupling of the unpaired electron with the 31 P nucleus. Further one-electron removal from the radical cations 4a and 4b is also feasible with GaCl 3 , affording the dications [{(IPr)C(Ph)}P(cAAC R )](GaCl 4 ) 2 (R = Me 5a , Cy 5b ) as yellow crystals. The molecular structures of compounds 3-5 have been determined by X-ray diffraction and analyzed by DFT calculations., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An improved synthesis of the simplest nitric acid ester, methyl nitrate, and a new synthesis of fluoromethyl nitrate use the metathesis of the corresponding iodomethanes with silver nitrate. Both compounds were identified by spectroscopy and the structures determined for in situ grown crystals by X-ray diffraction as well as in the gas phase by electron diffraction. Fluorination leads to structures with shorter C-O and N-O bonds, has an energetically destabilizing effect and increases friction sensitivity, but decreases detonation performance., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

The divinyldiarsene radical cations [{(NHC)C(Ph)}As] 2 (GaCl 4 ) (NHC=IPr: C{(NDipp)CH} 2 3; SIPr: C{(NDipp)CH 2 } 2 4; Dipp=2,6-iPr 2 C 6 H 3 ) and dications [{(NHC)C(Ph)}As] 2 (GaCl 4 ) 2 (NHC=IPr 5; SIPr 6) are readily accessible as crystalline solids on sequential one-electron oxidation of the corresponding divinyldiarsenes [{(NHC)C(Ph)}As] 2 (NHC=IPr 1; SIPr 2) with GaCl 3 . Compounds 3-6 have been characterized by X-ray diffraction, cyclic voltammetry, EPR/NMR spectroscopy, and UV/vis absorption spectroscopy as well as DFT calculations. The sequential removal of one electron from the HOMO, that is mainly the As-As π-bond, of 1 and 2 leads to successive elongation of the As=As bond and contraction of the C-As bonds from 1/2→3/4→5/6. The UV/vis spectrum of 3 and 4 each exhibits a strong absorption in the visible region associated with SOMO-related transitions. The EPR spectrum of 3 and 4 each shows a broadened septet owing to coupling of the unpaired electron with two 75 As (I=3/2) nuclei., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

A series of unique C 2 P 3 -ring compounds [(ADC Ar )P 3 ] (ADC Ar = ArC{(DippN)C} 2 ; Dipp = 2,6-iPr 2 C 6 H 3 ; Ar = Ph 4a , 3-MeC 6 H 4 4b , 4-MeC 6 H 4 4c , and 4-Me 2 NC 6 H 4 4d ) are readily accessible in an almost quantitative yield by the direct functionalization of white phosphorus (P 4 ) with appropriate anionic dicarbenes [Li(ADC Ar )]. The formation of 1,2,3-triphosphol-2-ides ( 4a-4d ) suggests unprecedented [3 + 1] fragmentation of P 4 into P 3 + and P - . The P 3 + cation is trapped by the (ADC Ar ) - to give 4 , while the putative P - anion reacts with additional P 4 to yield the Li 3 P 7 species, a useful reagent in the synthesis of organophosphorus compounds. Remarkably, the P 4 fragmentation is also viable with the related mesoionic carbenes (iMICs Ar ) (iMIC Ar = ArC{(DippN) 2 CCH}, i stands for imidazole-based) giving rise to 4 . DFT calculations reveal that both the C 3 N 2 and C 2 P 3 -rings of 4 are 6π-electron aromatic systems. The natural bonding orbital (NBO) analyses indicate that compounds 4 are mesoionic species featuring a negatively polarized C 2 P 3 -ring. The HOMO-3 of 4 is mainly the lone-pair at the central phosphorus atom that undergoes σ-bond formation with a variety of metal-electrophiles to yield complexes [{(ADC Ar )P 3 }M(CO) n ] (M = Fe, n = 4, Ar = Ph 5a or 4-Me-C 6 H 4 5b ; M = Mo, n = 5, Ar = Ph 6 ; M = W, n = 5, Ar = 4-Me 2 NC 6 H 4 7 )., (This journal is © The Royal Society of Chemistry 2019.)

The synthesis and characterization of the crystalline diphosphene radical cations [{(NHC)C(Ph)}P]2(GaCl4) (NHC = IPr = C{(NDipp)CH}23, SIPr = C{(NDipp)CH2}24; Dipp = 2,6-iPr2C6H3) and dications [{(NHC)C(Ph)}P]2(GaCl4)2 (NHC = IPr 5, SIPr 6) featuring a π-conjugated C2P2C2-framework has been reported.

The first divinyldiarsenes [{(NHC)C(Ph)}As] 2 (NHC=IPr 3 a, SIPr 3 b; IPr=C{(NAr)CH} 2 ; SIPr=C{(NAr)CH 2 } 2 ; Ar=2,6-iPr 2 C 6 H 3 ) are reported. Compounds 3 a and 3 b were prepared by the reduction of corresponding chlorides {(NHC)C(Ph)}AsCl 2 (NHC=IPr 2 a, SIPr 2 b) with Mg. Calculations revealed a small HOMO-LUMO energy gap of 3.86 (3 a) and 4.24 eV (3 b). Treatment of 3 a with (Me 2 S)AuCl led to the cleavage of the As=As bond to restore 2 a, which is expected to proceed via the diarsane [{(IPr)C(Ph)}AsCl] 2 (4). Remarkably, 4 as well as 2 a can be selectively accessed on treatment of 3 a with an appropriate amount of C 2 Cl 6 . Moreover, 3 a readily reacts with PhEEPh (E=Se or Te) at room temperature to give {(IPr)C(Ph)}As(EPh) 2 (E=Se 5 a; Te 5 b), revealing the cleavage of As=As and E-E bonds and the formation of As-E bonds. Such highly selective stepwise oxidation (3 a→4→2 a) and bond metathesis (3 a→5 a,b) reactions are unprecedented in main-group chemistry., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chlorogermane (C 2 F 5 ) 3 GeCl with very electronegative pentafluoroethyl groups was converted with LiCH 2 P(tBu) 2 to obtain the intramolecular frustrated Lewis pair (FLP) (C 2 F 5 ) 3 GeCH 2 P(tBu) 2 , a neutral, germanium-based FLP. Its reactivity was compared to its silicon homologue (C 2 F 5 ) 3 SiCH 2 P(tBu) 2 . Both FLPs cleave NO but give cyclic (Si) and open-chain oxides (Ge). In reactions with HCl both FLPs gave the same adduct type in the solid state, while the proton seems more mobile in solution in the germanium case. Reactions with PhCNO and Me 3 SiCHN 2 result in ring-type adducts. The structures of (C 2 F 5 ) 3 GeCH 2 P(tBu) 2 and of five adducts with substrates were elucidated by X-ray diffraction. The study clearly showed the germanium compound to have a more moderate Lewis acidity compared to the silicon analogue., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Bidentate boron Lewis acids based on 1,8-diethynylanthracene were synthesised in two steps by initial stannylation of the terminal alkynes and subsequent tin-boron exchange with different chloroboranes. The reactions were very selective, and the target compounds were obtained in high purity and good to excellent yields. Complexation experiments of 1,8-bis[(diphenylboranyl)ethynyl]anthracene with nitrogen bases (pyridine, pyrimidine, TMEDA) afforded three stable adducts, which were structurally characterised by X-ray diffraction. Competition experiments demonstrated the selective exchange of guests, and quantum-chemical calculations provided information on their energetics. NMR experiments at low temperature gave insight into the dynamic behaviour of the TMEDA adduct., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In situ grown crystals of CF3I and CF3CH2I are dominated by II and FF interactions. Their co-crystals with benzene, (CF3I)2·C6H6 and CF3CH2I·C6H6, contain two completely different sets of intermolecular interactions. (CF3I)2·C6H6 shows a unique halogen-bond type: above-the-bond C-IπC6H6 interactions. CF3CH2I·C6H6 shows above-the-centre C-HπC6H6 interactions. These interactions are electrostatically dominated type II halogen bonds between single halogenoalkane molecules and weaker dispersion dominated interactions between the co-crystal components. The observed preferences for benzene for the two binding partners match with calculated molecular electrostatic potentials.

The synthesis, structure, and reactivity of the first silylene-functionalized N-heterocyclic carbene (Si-NHC), {(L 1 )Si}(L 2 ), (3) (L 1 =PhC(NtBu) 2 , L 2 =CCH(CNAr) 2 C:, Ar=2,6-diisopropylphenyl) are reported. The ditopic carbanionic-NHC (dc-NHC), [Li(L 2 )] ∞ (1) reacts with the monochlorosilylene (L 1 )SiCl (2) to afford 3. The HOMO of 3 is the silylene lone-pair orbital, whereas the HOMO-1 is located at the carbene carbon atom. Both Si II and C II functionalities of 3 undergo reactions with chalcogens to give heavier ketone derivatives {(L 1 )Si(E)}L 2 (E) (E=S, 4; Se, 5; and Te, 6). Compounds 4-6 feature a highly polarized Si δ+ -E δ- bond with a formal charge of -0.72 (4), -0.64 (5), and -0.50 e (6) on the E atom. The Wiberg bond indices of 1.64 (4), 1.66 (5), and 1.63 (6) for the Si-E bond however indicate a moderate p π -p π interaction between Si and E atoms. Compound 3 functions as a reducing agent and induces disproportionation of Si 2 Cl 6 to yield the silyl-functionalized NHC, {(L 1 )SiCl 2 }(L 2 ) (7). Treatment of 3 with HSiCl 3 leads to the formation of the silyl-functionalized imidazolium salt [{(L 1 )SiCl 2 }(L 2 H)]Cl (8). The silylene moiety of 3 readily forms the iridium-silylene complex [{(L 2 )(L 1 )Si}Ir(cod)Cl] (9) featuring a free NHC ligand on treatment with [Ir(cod)(μ-Cl)] 2 ., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background and Aims: Transjugular intrahepatic portosystemic shunt (TIPS) is the treatment of choice in decompensated portal hypertension. TIPS revision due to thrombosis or stenosis increases morbidity and mortality. Our aim was to investigate patient- and procedure-associated risk factors for TIPS-revision., Patients and Methods: We retrospectively evaluated 189 patients who underwent the TIPS procedure. Only patients who required TIPS revision within 1 year (Group I, 34 patients) and patients who did not require re-intervention within the first year (Group II [control group], 54 patients) were included., Results: Out of 88 patients, the majority were male (69.3%) and mean age was 56 ± 11 years. Indications for TIPS were refractory ascites (68%), bleeding (24%), and Budd-Chiari syndrome (8%). The most frequent liver disease was alcohol-induced cirrhosis (60%). Forty-three patients (49%) received bare and 45 patients (51%) covered stents, thus resulting in reduction of hepatic venous pressure gradient (HVPG) from 19.0 to 9.0 mm Hg. When comparing patient- and procedure-related factors, the type of stent (p < 0.01) and interventionalist's experience (number of performed TIPS implantations per year; p < 0.05) were the only factors affecting the risk of re-intervention due to stent dysfunction, while age, gender, indication, Child-Pugh, and model of end-stage liver disease score, platelet count, pre- and post-HVPG, additional variceal embolization, stent diameter, and number of stents did not significantly differ., Conclusion: Patients undergoing TIPS procedure should be surveilled closely for shunt dysfunction while covered stents and high-level experience are associated with increased -patency., (© 2018 S. Karger AG, Basel.)

The covalent diamantyl (C 28 H 38 ) and oxadiamantyl (C 26 H 34 O 2 ) dimers are stabilized by London dispersion attractions between the dimer moieties. Their solid-state and gas-phase structures were studied using a multitechnique approach, including single-crystal X-ray diffraction (XRD), gas-phase electron diffraction (GED), a combined GED/microwave (MW) spectroscopy study, and quantum chemical calculations. The inclusion of medium-range electron correlation as well as the London dispersion energy in density functional theory is essential to reproduce the experimental geometries. The conformational dynamics computed for C 26 H 34 O 2 agree well with solution NMR data and help in the assignment of the gas-phase MW data to individual diastereomers. Both in the solid state and the gas phase the central C-C bond is of similar length for the diamantyl [XRD, 1.642(2) Å; GED, 1.630(5) Å] and the oxadiamantyl dimers [XRD, 1.643(1) Å; GED, 1.632(9) Å; GED+MW, 1.632(5) Å], despite the presence of two oxygen atoms. Out of a larger series of quantum chemical computations, the best match with the experimental reference data is achieved with the PBEh-3c, PBE0-D3, PBE0, B3PW91-D3, and M06-2X approaches. This is the first gas-phase confirmation that the markedly elongated C-C bond is an intrinsic feature of the molecule and that crystal packing effects have only a minor influence.

Three compounds with phenyl and pentafluorophenyl rings bridged by (CH 2 ) 3 and (CH 2 ) 2 SiMe 2 units were synthesized by hydrosilylation and C-C coupling reactions. Their solid-state structures are dominated by intermolecular π stacking interactions, primarily leading to dimeric or chain-type aggregates. Analysis of free molecules in the gas phase by electron diffraction revealed the most abundant conformer to be significantly stabilized by intramolecular π-π interactions. For the silicon compounds, structures characterized by σ-π interactions between methyl and pentafluorophenyl groups are second lowest in energy and cannot be excluded completely by the gas electron diffraction experiments. C 6 H 5 (CH 2 ) 3 C 6 F 5 , in contrast, is present as a single conformer. The gas-phase structures served as a reference for the evaluation of a series of (dispersion-corrected) quantum-chemical calculations., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Tris[tetrafluoro-4-(trifluoromethyl)phenyl]borane (BTolF) was prepared by treating boron tribromide with tetrameric F 3 CC 6 F 4 -Cu I . The F 3 CC 6 F 4 -Cu I was generated from F 3 CC 6 F 4 MgBr and copper(I) bromide. Lewis acidities of BTolF evaluated by the Gutmann-Beckett method and calculated fluoride-ion affinities are 9 and 10 %, respectively, higher than that of tris(pentafluorophenyl)borane (BCF) and even higher than that of SbF 5 . The molecular structures of BTolF and BCF were determined by gas-phase electron diffraction, that of BTolF also by single-crystal X-ray diffraction., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The gas-phase structure of 1,8-bis[(trimethylsilyl)ethynyl]anthracene (1,8-BTMSA) was determined by a combined gas electron diffraction (GED)/mass spectrometry (MS) experiment as well as by quantum-chemical calculations (QC). DFT and dispersion corrected DFT calculations (DFT-D3) predicted two slightly different structures for 1,8-BTMSA concerning the mutual orientation of the two -C-C[triple bond, length as m-dash]C-SiMe 3 units: away from one another or both bent to the same side. An attempt was made to distinguish these structures by GED structural analysis. To probe the structural rigidity, a set of Born-Oppenheimer molecular dynamics (BOMD) calculations has been performed at the DFT-D level. Vibrational corrections Δr = r a - r e were calculated by two BOMD approaches: a microcanonically (NVE) sampled ensemble of 20 trajectories (BOMD(NVE)) and a canonical (NVT) trajectory thermostated by the Noose-Hoover algorithm (BOMD(NVT)). In addition, the conventional approach with both, rectilinear and curvilinear approximations (SHRINK program), was also applied. Radial distribution curves obtained with models using both MD approaches provide a better description of the experimental data than those obtained using the rectilinear (SHRINK) approximation, while the curvilinear approach turned out to lead to physically inacceptable results. The electronic structure of 1,8-BTMSA was investigated in terms of an NBO analysis and was compared with that of the earlier studied 1,8-bis(phenylethynyl)anthracene. Theoretical and experimental results lead to the conclusion that the (trimethylsilyl)ethynyl (TMSE) groups in 1,8-BTMSA are neither restricted in rotation nor in bending at the temperature of the GED experiment.

Background & Aims: Patients with progressive liver disease exhibit complex coagulation disorders. Factor XIII plays a crucial role in the last steps of haemostasis, and its deficiency is associated with an increased incidence of bleeding diathesis. However, current conventional coagulation tests cannot detect factor XIII deficiency. In this study, we examined factor XIII activity and the ability of rotational thromboelastometry to detect factor XIII deficiency and bleeding diathesis in patients with cirrhosis., Methods: We retrospectively studied 74 patients with cirrhosis, comparing the results of conventional coagulation tests (international normalized ratio, activated partial thromboplastin time, platelet count, fibrinogen level), rotational thromboelastometry, factor XIII activity and clinical scores., Results: Patients with cirrhosis exhibited reduced factor XIII activity. Factor XIII activity was positively correlated with conventional coagulation parameters and rotational thromboelastometry values, such as maximum clot formation (MCF) extem (r=.48, P<.0001) and MCF fibtem (r=.60, P<.0001). However, maximum lysis (ML) extem and ML aptem were not correlated with factor XIII activity. Three-month mortality rates (P=.0469) and bleeding complications (P<.0001) were significantly associated with lower factor XIII activity. Patients with haemorrhage exhibited significantly altered rotational thromboelastometry values., Conclusions: Reduced levels of MCF extem and MCF fibtem but not high levels of ML extem and ML aptem are associated with factor XIII deficiency in patients with liver disease. Therefore, substituting factor XIII should be considered for such patients to strengthen clot formation in patients experiencing haemorrhage or those who have undergone interventions., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The doubly acid-functionalised aniline PhN[(CH 2 ) 3 B(C 6 F 5 ) 2 ] 2 shows rapidly exchanging boron acid groups at the central base function and is an active frustrated Lewis pair due to cooperative hydride binding by both Lewis acids. Here we report investigations on the effect of different substituents at the central nitrogen atom and on the effect of exchanging nitrogen by phosphorus. Treatment of diallyl-tert-butylaniline with one equivalent of HB(C 6 F 5 ) 2 led to formation of a seven-membered iminium hydridoborate ring; after mono-hydroboration the intermediately formed frustrated Lewis pair reacts with the second allylamine function under ring closure. Phosphorus based Lewis pairs with two acid sites were prepared by hydroboration of diallylphenylphosphane and diallyl-tert-butylphosphane. Unlike the aniline PhN[(CH 2 ) 3 B(C 6 F 5 ) 2 ] 2 the doubly hydroborated species ( t Bu/Ph)P[(CH 2 ) 3 B(C 6 F 5 ) 2 ] 2 show no dynamic exchange of the boron Lewis acid functions in solution and are not catalytically active in terms of H/D-scrambling as well as hydrogenation reactions. Quantum-chemical investigations revealed the B-P bond dissociation Gibbs free energy to be much larger than those of the nitrogen analogue. The absence of an active open form in solution prevents an activity in heterolytic hydrogen splitting.

The doubly Lewis-acid functionalised aniline PhN[(CH2)3B(C6F5)2]2 features two competing boron functions in fast exchange for binding to the central Lewis base. It shows catalytic activity typical for FLPs in H/D-scrambling and catalytic hydrogenation experiments. By contrast, the singly acid-functionalised PhMeN(CH2)3B(C6F5)2 reveals a dramatically smaller catalytic activity in analogous experiments.

The molecular structure and conformational properties of 2,2,2-trichloroethyl chloroformate, ClC(O)OCH2CCl3 were determined experimentally using gas-phase electron diffraction (GED) and theoretically based on quantum-chemical calculations at the MP2 and DFT levels of theory. Further experimental measurements such as UV-visible, IR and Raman spectroscopy were complemented with the corresponding theoretical studies. All experimental results and calculations confirm the presence of two conformers namely anti-gauche (C1 symmetry) and anti-anti (Cs symmetry). The conformational preference was rationalised by NBO and AIM analyses. Molecular properties such as ionisation potential, electronegativity, chemical potential, chemical hardness and softness were deduced from HOMO-LUMO analyses. The TD-DFT approach was applied to assign the electronic transitions observed in the UV-visible spectrum. A detailed interpretation of the infrared and Raman spectra of the title compound are reported. Using calculated frequencies as a guide, IR and Raman spectra also provide evidence for the presence of both C1 and Cs conformers.

The charge density distribution of the trimethylaluminum dimer was determined by high-angle X-ray diffraction of a single crystal and quantum-chemical methods and analyzed using the quantum theory of atoms in molecules. The data can be interpreted as Al2Me6 being predominantly ionically bonded, with clear indications of topological asymmetry for the bridging Al-C bonds owing to delocalized multicenter bonding. This interpretation is supported by the calculated magnetic response currents. The data shed new light on the bonding situation in this basic organometallic molecule, which was previously described by contradicting interpretations of bonding., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Portal hypertension occurs frequently in advanced liver cirrhosis and accounts for the majority of lethal complications. Compensatory splanchnic vasodilation and counter regulatory mechanisms (e.g. activation of the renin-angiotensin-aldosterone system) increase renal vascular resistance, which may facilitate acute kidney injury and the development of hepatorenal syndrome (HRS). HRS represents a functional, yet reversible renal impairment with elevated serum creatinine levels. Establishing the diagnosis, fluid challenge test and several investigations are needed to exclude acute kidney injury and other causes of renal failure. Early treatment with albumin and vasoconstrictors improves the prognosis of HRS patients. The only curative treatment of HRS so far is improvement of liver function implying liver transplantation in many cases. TIPS placement may be useful as a bridging tool to transplantation unless hepatic encephalopathy is present. Spontaneous bacterial peritonitis (SBP) is a relevant, independent risk factor for HRS. In patients with liver cirrhosis and SBP in addition to antibiotics, preventive albumin treatment is recommended., (© Georg Thieme Verlag KG Stuttgart · New York.)

Starting from ferrocene, pentafluoroferrocene [Fe(C5F5)(C5H5)] can be prepared in five steps via a one-pot lithiation-electrophilic fluorination strategy. Pentafluoroferrocene was characterized by multinuclear NMR and IR spectroscopy, by cyclovoltammetry as well as X-ray (solid) and electron diffraction (gas) and the experimental results compared with DFT calculations.

Background/aims: For diagnosis, prognosis, and treatment of acute liver failure (ALF), macroscopic evaluation and histological assessment of the liver are important. Due to impaired coagulation in ALF, the risk of bleeding is high after a percutaneous liver biopsy. Our aims were to assess (i) safety and benefit of mini laparoscopy (ML) in patients with ALF and (ii) the potential utility of histological markers in ALF prognosis., Methods: ML was performed in 39 patients with ALF to assess liver surface and to obtain a liver biopsy. Serological markers of liver injury and immunohistochemical detection of cell death and proliferation were compared to a non-ALF group (n = 10)., Results: Liver biopsies were successfully performed in all patients with no significant complications. All patients had markedly elevated M30 and M65 levels in the serum. In the liver, M30 and Ki67 immune-reactive cells were more abundant in those with ALF. Importantly, there were significantly more Ki67-positive cells but fewer M30-positive cells in livers of ALF patients who recovered spontaneously., Conclusion: ML with liver biopsy in patients with ALF and severe coagulopathy is safe. Immunohistochemical detection of liver cell death and regeneration may identify individuals who would recover spontaneously or who would need a liver transplant., (© 2014 S. Karger AG, Basel.)