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In this paper we describe a practical method of partial-match retrieval in very large data files. A binary code word, called a descriptor, is associated with each record of the file. These record descriptors are then used to form a derived descriptor for a block of several records, which will serve as an index for the block as a whole; hence, the name "indexed descriptor files." First the structure of these files is described and a simple, efficient retrieval algorithm is presented. Then its expected behavior, in terms of storage accesses, is analyzed in detail. Two different tile creation procedures are sketched, and a number of ways in which the file organization can be "tuned" to a particular application are suggested. [ABSTRACT FROM AUTHOR]

Any region can be regarded as a union of maximal neighborhoods of its points, and can be specified by the centers and radii of these neighborhoods; this set is a sort of "skeleton" of the region. The storage required to represent a region in this way is comparable to that required when it is represented by encoding its boundary. Moreover, the skeleton representation seems to have advantages when it is necessary to determine repeatedly whether points are inside or outside the region, or to perform set-theoretic operations on regions. [ABSTRACT FROM AUTHOR]

ABSTRACTBackground:Post-traumatic growth (PTG) and resilience, regarded as positive psychological change following a traumatic experience, are under-researched across cultures in people exposed to child maltreatment (CM).Objective:We investigated how experiences and the perceived acceptability of CM are related to resilience and PTG in countries with different cultures, living standards, and gross national income.Method:A total of 478 adults from Cameroon (n = 111), Canada (n = 137), Japan (n = 108), and Germany (n = 122) completed an online survey with self-reported questionnaires, including the Brief Resilience Scale and the Post Traumatic Growth Inventory-Short Form.Results:Across countries, self-reported male gender and age were positively associated with resilience, while experiences of physical abuse and emotional maltreatment were negatively associated with resilience. Experiences of emotional maltreatment were positively associated with PTG. Higher levels of PTG and resilience were found amongst Cameroonian participants as compared to other countries.Conclusion:Our results suggest that positive changes following CM can vary significantly across cultures and that experiences of specific CM subtypes, but not the perceived acceptability of CM, may be important for a deeper understanding of how individuals overcome trauma and develop salutogenic outcomes. Our findings may inform CM intervention programmes for an enhanced cultural sensitivity.

ABSTRACTBackground:Individuals with child maltreatment (CM) experiences show alterations in emotion recognition (ER). However, previous research has mainly focused on populations with specific mental disorders, which makes it unclear whether alterations in the recognition of facial expressions are related to CM, to the presence of mental disorders or to the combination of CM and mental disorders, and on ER of emotional, rather than neutral facial expressions. Moreover, commonly, recognition of static stimulus material was researched.Objective:We assessed recognition of dynamic (closer to real life) negative, positive and neutral facial expressions in individuals characterised by CM, rather than a specific mental disorder. Moreover, we assessed whether they show a negativity bias for neutral facial expressions and whether the presence of one or more mental disorders affects recognition.Methods:Ninety-eight adults with CM experiences (CM+) and 60 non-maltreated (CM−) adult controls watched 200 non-manipulated coloured video sequences, showing 20 neutral and 180 emotional facial expressions, and indicated whether they interpreted each expression as neutral or as one of eight emotions.Results:The CM+ showed significantly lower scores in the recognition of positive, negative and neutral facial expressions than the CM− group (p < .050). Furthermore, the CM+ group showed a negativity bias for neutral facial expressions (p < .001). When accounting for mental disorders, significant effects stayed consistent, except for the recognition of positive facial expressions: individuals from the CM+ group with but not without mental disorder scored lower than controls without mental disorder.Conclusions:CM might have long-lasting influences on the ER abilities of those affected. Future research should explore possible effects of ER alterations on everyday life, including implications of the negativity bias for neutral facial expressions on emotional wellbeing and relationship satisfaction, providing a basis for interventions that improve social functioning.

Lobular capillary hemangioma (LCH) is a polypoid form of capillary hemangioma occurring on the skin and mucosal surfaces. While LCH of the oral and nasal cavity is a well-known entity, [...]

Programmed death ligand 1 (PD-L1) is expressed by 20% to 57% of systemic diffuse large B cell lymphomas (DLBCLs). PD-L1 expression in primary cutaneous DLBCL (pcDLBCL) has not been studied so far. Sixteen paraffin-embedded tissue samples of pcDLBCL (13 leg type [LT], 3 others [OT]) were investigated for PD-1, PD-L1, and CD33 expression and the cellular composition of the tumor microenvironment, focusing on myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages. Membrane-bound PD-L1 expression by the tumor cells was observed in all samples, albeit to a variable extent (19.9%). As expected, most DLBCL-LT (10 cases) were classified as activated B cell like type, with a higher PD-L1 score (21.9%) compared with that of the germinal center B cell like type (7.7%). The surrounding infiltrate consisted predominately of CD163(+) M2 rather than CD68(+) macrophages (CD68:CD163=1:4 to 6). Moreover, a considerable proportion of CD33(+) MDSCs with PD-L1 coexpression was admixed. Tumor cells expressed CD33 to variable degrees (2% to 60%). The number of MDSCs or M2 macrophages did not correlate with pcDLBCL subtypes LT or OT. T cells were only a minor component of the tumor microenvironment. We propose that PD-L1(+) tumor cells and PD-L1(+) MDSCs shield the tumor against PD-1(+) tumor-infiltrating lymphocytes, consequently leading to inhibition and diminution of tumor-infiltrating lymphocytes. Moreover, we found a polarization to M2 macrophages, which may contribute to the poor prognosis of DLBCL patients. Thus, targeting of tumor cells and MDSCs using anti-PD-1/anti-PD-L1 or anti-CD33 antibodies might be a worthwhile new approach to treat this aggressive form of cutaneous B-cell lymphoma.

ABSTRACTBackground:The most used questionnaires for PTSD screening in adults were developed in English. Although many of these questionnaires were translated into other languages, the procedures used to translate them and to evaluate their reliability and validity have not been consistently documented. This comprehensive scoping review aimed to compile the currently available translated and evaluated questionnaires used for PTSD screening, and highlight important gaps in the literature.Objective:This review aimed to map the availability of translated and evaluated screening questionnaires for posttraumatic stress disorder (PTSD) for adults.Methods:All peer-reviewed studies in which a PTSD screening questionnaire for adults was translated, and which reported at least one result of a qualitative and /or quantitative evaluation procedure were included. The literature was searched using Embase, MEDLINE, and APA PsycInfo, citation searches and contributions from study team members. There were no restrictions regarding the target languages of the translations. Data on the translation procedure, the qualitative evaluation, the quantitative evaluation (dimensionality of the questionnaire, reliability, and performance), and open access were extracted.Results:A total of 866 studies were screened, of which 126 were included. Collectively, 128 translations of 12 different questionnaires were found. Out of these, 105 (83.3%) studies used a forward and backward translation procedure, 120 (95.2%) assessed the reliability of the translated questionnaire, 60 (47.6%) the dimensionality, 49 (38.9%) the performance, and 42 (33.3%) used qualitative evaluation procedures. Thirty-four questionnaires (27.0%) were either freely available or accessible on request.Conclusions:The analyses conducted and the description of the methods and results varied substantially, making a quality assessment impractical. Translations into languages spoken in middle- or low-income countries were underrepresented. In addition, only a small proportion of all translated questionnaires were available. Given the need for freely accessible translations, an online repository was developed.HIGHLIGHTSWe mapped the availability of translated PTSD screening questionnaires.The quality of the translation and validation processes is very heterogenous.We created a repository for translated, validated PTSD screening questionnaires.

Obsessive-compulsive disorder (OCD) is a severe anxiety disorder characterized by frequent obsessive thoughts and repetitive behaviors. Neuroticism is a vulnerability factor for OCD, yet the mechanisms by which this general vulnerability factor affects the development of OCD-related symptoms are unknown. The present study assessed a hierarchical model of the development of obsessive thoughts that includes neuroticism as a general, higher-order factor, and specific, potentially maladaptive thought processes (thought suppression, worry, and brooding) as second-order factors manifesting in the tendency toward obsessing. A total of 238 participants completed questionnaires assessing the examined constructs. The results of mediator analyses demonstrated the hypothesized relationships: A positive association between neuroticism and obsessing was mediated by thought suppression, worry, and brooding. Independent of the participant’s sex, all three mediators contributed equally and substantially to the association between neuroticism and obsessing. These findings extend earlier research on hierarchical models of anxiety and provide a basis for further refinement of models of the development of obsessive thoughts.

ABSTRACTBackgroundSyrian refugees in Switzerland face several barriers in accessing mental health care. Cost-effective psychological interventions are urgently needed to meet the mental health needs of refugees. Problem Management Plus (PM+) is an evidence-based, psychological intervention delivered by trained non-specialist ‘helpers’.ObjectiveTo assess the feasibility and acceptability of PM+ among Syrian refugees in Switzerland.MethodsWe conducted a single-blind pilot randomized controlled trial (RCT) with Syrian refugees impaired by psychological distress (K10 > 15 and WHODAS 2.0 > 16). Participants were randomized to PM+ or Enhanced Treatment As Usual (ETAU). Participants were assessed at baseline, and 1 week and 3 months after the intervention, and completed measures indexing mental health problems and health care usage. Semi-structured interviews were conducted with different stakeholders.ResultsN= 59 individuals were randomized into PM+ (n= 31) or ETAU (n= 28). N= 18 stakeholders were interviewed about facilitators and barriers for the implementation of PM+. Retention rates in the trial (67.8%) and mean intervention attendance (M= 3.94 sessions, SD = 1.97) were high. No severe events related to the study were reported. These findings indicate that the trial procedures and PM+ were feasible, acceptable and safe.ConclusionsThe findings support the conduct of a definitive RCT and show that PM+ might have the potential to be scaled-up in Switzerland. The importance, as well as the challenges, of implementing and scaling-up PM+ in high-income countries, such as Switzerland, are discussed.

ABSTRACTBackgroundChildhood maltreatment (CM) is frequently linked to interpersonal problems such as difficulties in social relationships, loneliness, and isolation. These difficulties might partly stem from troubles regulating comfortable interpersonal distance (CIPD).ObjectiveWe experimentally investigated whether CM manifests in larger CIPD and whether all subtypes of CM (i.e., physical, emotional, or sexual abuse and physical or emotional neglect) affect CIPD.MethodsUsing the stop-distance method (i.e. a team member approached participants until the latter indicated discomfort), we assessed CIPD in 84 adults with a self-reported history of CM (24 with depressive symptoms) and 57 adult controls without a history of CM (without depressive symptoms).ResultsAdults with CM showed a larger CIPD (Mdn = 86 cm) than controls (Mdn = 68 cm), and CIPD was largest for those with CM combined with current depressive symptoms (Mdn = 145 cm) (p’s < .047). In the latter group, all subtypes of CM were associated with a larger CIPD compared to controls (p’s < .045). In the CM group without depressive symptoms, only those with emotional abuse (p = .040) showed a larger CIPD than controls.ConclusionsThese results add to findings of differential socio-emotional long-term consequences of CM, depending upon the subtype of CM. Future research should explore whether a larger CIPD has a negative impact on social functioning in individuals exposed to CM, particularly in those with depressive symptoms.HIGHLIGHTSAdults with child maltreatment (CM) prefer larger physical distances.• This effect is more pronounced in those with CM and depressive symptoms.• Troubled regulation of physical distance might contribute to interpersonal problems.

A mathematical model for dynamic networks is developed that is based on closed, rather than open, sets. For a social network, it seems appropriate to use a neighborhood concept to establish these sets. We then define a rigorous concept of continuous change, and show that it shares some of the properties associated with the continuity of the calculus. We demonstrate that continuity is local in nature, in that if the network change is discontinuous, it will be so at a single point and the discontinuity will be apparent in that point’s immediate neighborhood. Necessary and sufficient criteria for continuity are provided when the change involves only the addition, or deletion, of individual nodes or connections (edges). To illustrate large scale continuous change, we choose a practical process which reduces a complex network to its fundamental cycles, in the course of which most triadically closed subportions are removed. Finally, we explore several variants of the neighborhood concept, and prove that a rigorous notion of fuzzy closure can be defined.

Choose the right ligand: An iridium complex derived from a phosphino–imidazoline ligand is a highly efficient catalyst for the asymmetric hydrogenation of terminal vinyl boronic esters (see scheme). On the other hand, trisubstituted alkenyl‐boronates can be reduced with high activity and good to excellent enantioselectivity employing a pyridine–phosphinite ligand.

A series of 1,2‐disubstituted cyclohexene derivatives was prepared through Suzuki–Miyaura cross‐coupling of 2‐bromo‐1‐cyclohexenecarbaldehyde or 2‐carbomethoxy‐1‐cyclohexen‐1‐yl triflate with arylboronates. These tetra‐substituted cyclic alkenes were subjected to Ir‐catalyzed asymmetric hydrogenation. In this way cis‐1‐methoxymethyl‐2‐arylcyclohexanes were obtained in high yield with excellent enantio‐ and diastereoselectivities (up to >99 % ee, >99 % cis) by using phosphinomethyloxazolines as ligands. Asymmetric hydrogenation of analogous cyclopentene derivatives, prepared by Suzuki–Miyaura cross‐coupling, proved to be more difficult and proceeded with lower enantioselectivities of up to 88 % ee. The synthetic potential of this cross‐coupling/asymmetric‐hydrogenation strategy was demonstrated by an enantioselective route to chiral hexahydrofluorenones.

Primary cutaneous CD30+lymphoproliferative disorders (CD30+LPDs) are the second most common form of cutaneous T-cell lymphomas and include lymphomatoid papulosis and primary cutaneous anaplastic large-cell lymphoma. Despite the anaplastic cytomorphology of tumor cells that suggest an aggressive course, CD30+LPDs are characterized by an excellent prognosis. Although a broad spectrum of therapeutic strategies has been reported, these have been limited mostly to small retrospective cohort series or case reports, and only very few prospective controlled or multicenter studies have been performed, which results in a low level of evidence for most therapies. The response rates to treatment, recurrence rates, and outcome have not been analyzed in a systematic review. Moreover, international guidelines for staging and treatment of CD30+LPDs have not yet been presented. Based on a literature analysis and discussions, recommendations were elaborated by a multidisciplinary expert panel of the Cutaneous Lymphoma Task Force of the European Organization for Research and Treatment of Cancer, the International Society for Cutaneous Lymphomas, and the United States Cutaneous Lymphoma Consortium. The recommendations represent the state-of-the-art management of CD30+LPDs and include definitions for clinical endpoints as well as response criteria for future clinical trials in CD30+LPDs.

P,O joins the mix: P,O ligands (L1) form efficient iridium catalysts for the asymmetric hydrogenation of olefins. The proline‐derived ligands lead to high enantioselectivities with several classes of alkenes, most notably with α,β‐unsaturated carboxylic esters and ketones, where they match or even surpass the eevalues reported for the best N,P and C,N ligands.

Ein Weg für alle: Die Entwicklung von Substanzen, die Neuritenwachstum induzieren, könnte ein wertvoller Ansatz zur Entdeckung potenzieller Medikamente gegen neurodegenerative Krankheiten sein. Mithilfe eines difunktionellen Bausteins gelang die Totalsynthese einer ganzen Reihe von entomopathogenen Pilzen produzierter Pyridonpolyen‐Naturstoffe, welche die Differenzierung von PC‐12‐Zellen verursachen.

Unus pro omnibus: The development of compounds inducing neurite outgrowth might constitute a valuable approach for the non‐invasive medical treatment of neurodegenerative diseases. With the aid of a bifunctional building block, the total syntheses of a group of pyridone polyenes originally produced by entomopathogenic fungi was achieved (see picture). All of these natural products displayed neuritogenic activity in the PC‐12 cell line.

Several zwitterionic iridium complexes based on chiral P,N‐ligands with imidazoline or oxazoline donors and anionic tetraarylborate or aryltrifluoroborate substituents have been synthesized. The corresponding cationic analogues have also been prepared, to evaluate the effect of the covalent linkage between the anion and the cationic metal complex in catalytic reactions. The respective pairs of structurally analogous precatalysts have been compared for their efficacies in the asymmetric hydrogenation of unfunctionalized olefins. In most cases, the anionic derivatization has virtually no influence on the asymmetric induction of the iridium complex. This is in accordance with X‐ray structural studies, which have shown that the chiral environment of the cationic metal center is not affected by the anionic substituent. Depending on the nature of the counterion employed, the zwitterionic catalysts proved to be significantly more reactive than their cationic counterparts in nonpolar solvents.

Chiral iridium complexes with bicyclic pyridine‐based N,P ligands have emerged as efficient catalysts for the enantioselective hydrogenation of unfunctionalized trialkyl‐substituted olefins. Optimization of the reaction conditions by variation of the solvent, pressure, and temperature led to enantiomeric excesses of up to 99 %. Three pure alkenes, (E)‐2‐cyclohexyl‐2‐butene and (E)‐ and (Z)‐3,4‐dimethyl‐2‐pentene were converted into the corresponding chiral alkanes with 97 %, 94 %, and 93 % ee, respectively. Hydrogenation of the three CC bonds of both α‐ and γ‐tocotrienyl acetate led to α‐ and γ‐tocopheryl acetate with very high diastereoselectivity. The same catalysts were successfully applied in the hydrogenation of trisubstituted alkenes with a carboxylic ester or a keto group in the γ position. This reaction was used as a key step in a highly enantioselective synthesis of the pheromone of the caddisfly Hesperophylax occidentalis.The hydrogenation of a structurally analogous allylic alcohol also gave high enantioselectivities.

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Durchbruch für chirale SPOs: Die Kombination sekundärer Phosphanoxide (SPOs) mit Phosphanen ergibt hocheffektive chirale Liganden für übergangsmetallkatalysierte Hydrierungen. Gemischte zweizähnige Liganden wie JoSPOphos und TerSPOphos sind schnell zugänglich, und ihre Eigenschaften sind leicht variierbar. In der asymmetrischen Hydrierung funktionalisierter Alkene erzielten Rh‐Komplexe dieser Liganden bis 99 % eeund Umsatzfrequenzen bis 20 000 h−1.

We have evaluated a wide range of iridium complexes derived from chiral oxazoline‐based N,P ligands for the asymmetric hydrogenation of imines and identified three efficient catalysts. These catalysts are readily synthesized by straightforward convenient routes and are air and moisture stable. In the reduction of acetophenone N‐arylimines and related acyclic substrates, excellent enantioselectivities (up to 96 % ee) were obtained by using 0.1–0.5 mol % of catalyst at −20 °C and 5–50 bar hydrogen pressure.

Chiral indolinessubstituted at C‐2 or C‐3 can be prepared in high yield and excellent enantioselectivity by asymmetric hydrogenation of N‐protected indoles by using Ir catalysts with chiral N,P ligands. With less reactive substrates, the reaction had to be carried out at elevated temperature, but even at 60–110 °C very high enantiomeric excesses of up to 98–99 % could be obtained (see scheme).

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Shortcut to chiral catalysts: An efficient combinatorial strategy based on back reaction screening by ESI‐MS allows rapid evaluation of organocatalysts for the asymmetric Michael addition to α,β‐unsaturated aldehydes (see scheme). An unexpected nonlinear effect has been observed in this reaction, resulting from a double nucleophilic–electrophilic activation mechanism involving two catalyst molecules.

Starting from (R)‐N,N‐dimethyl‐1‐ferrocenylethylamine, a diastereoselective ortho‐lithiation procedure and a stereoconvergent intramolecular hydrophosphination gave access to P‐chiral ferrocenephospholanes. These mono‐ or bidentate ligands were converted to the corresponding rhodium and iridium complexes, including a chiral version of Crabtree’s catalyst, and tested in the asymmetric hydrogenation of functionalized and unfunctionalized olefins. A significant reactivity difference between the rhodium‐1,5‐cyclooctadiene and the rhodium‐norbornadiene complex was observed during catalyst activation.

To assess the external validity of laboratory baselines in panic disorder (PD), frequently associated with respiratory pattern abnormalities like increased respiratory variability and sighing, implying a stable pathophysiologic trait characteristic.

Optically active tertiary aminesare readily prepared by iridium‐catalyzed asymmetric hydrogenation of unfunctionalized enamines (see scheme). The best enantioselectivities with >90 % eewere obtained with N‐aryl‐ and N‐benzyl‐substituted enamines with a terminal double bond. The hydrogenation of enamines derived from cyclic ketones, which has not been reported yet with other catalysts, gave enantiomeric excesses of up to 87 %.

Anionic boron‐bridged bisoxazolines (borabox ligands) have been synthesized and characterized in their protonated forms. The ligands are tuneable over a wide range, allowing either alkyl or aryl substituents at the oxazoline rings and the central bridging boron atom. The structural parameters of this new ligand type have been investigated by X‐ray analyses of palladium and copper complexes. Electronic properties have been studied by 13C NMR spectroscopy and by DFT calculations on palladium allyl complexes and compared to those of analogous bisoxazoline (box) complexes. Borabox complexes are more electron‐rich at the metal center than their neutral box congeners, and as a consequence of the longer bonds between the bridging atom and the oxazoline rings, their bite angles are larger. Palladium(II) complexes bearing an unsubstituted allyl ligand and homoleptic copper(II) complexes each possess an almost flat chelate ring. NMR analysis of a (1,3‐diphenylallyl)(borabox)palladium complex showed a 92:8 mixture of (syn,syn) and (anti,syn) allyl isomers, in contrast with a previously reported box analogue that existed exclusively in the (syn,syn) form. Comparison of the corresponding crystal structures revealed that the distance between the bisoxazoline and the allyl ligand in the borabox complex is shorter. In the copper‐catalyzed allylic oxidation of cyclohexene and cyclopentene with tert‐butyl perbenzoate, borabox ligands gave results similar—and in some cases superior—to those obtained with analogous box ligands.

NArylation or Nalkylation of chiral 1,2diamines followed by ring closure with phosphorus trichloride PCl3 and subsequent coupling with an oxazoline alcohol resulted in a new class of N,P ligands. The corresponding iridium tetrakis3,5bistrifluormethylphenylborate BArF complexes were found to be efficient catalysts for the enantioselective hydrogenation of unfunctionalized olefins and α,βunsaturated carboxylic esters.

Metal complexes of boronbridged bisoxazolines borabox ligands were evaluated as catalysts for the Henry reaction. CopperII complexes induced high enantio and diastereoselectivity in reactions with nitroethane and nitropropane. The amount of base added had a strong influence on the formation of the chiral complex and the enantioselectivity. Comparison with the corresponding dimethylmethylenebridged bisoxazoline and other privileged ligands showed that borabox was the most suitable ligand system for the enantio and diastereoselective formation of nitroalcohols derived from nitropropane and aliphatic aldehydes.© WileyVCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008

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Four iridium complexes with achiral phosphino‐oxazoline (PHOX) ligands were readily prepared in two steps starting from commercially available phenyloxazolines. The air‐stable complexes with tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate (BArF) as counterion showed high reactivity in the hydrogenation of a range of tri‐ and tetrasubstituted olefins. The best results were obtained with an iridium complex (11) derived from a dicyclohexylphosphino‐oxazoline ligand bearing no additional substituents in the oxazoline ring. With several substrates, which gave only low conversion with the Crabtree catalyst, [Ir(Py)(PCy3)(COD)]PF6, full conversion was observed. The productivity of the Crabtree catalyst could be strongly increased by replacing the hexafluorophosphate anion with tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate. In one case, in the hydrogenation of a tetraalkyl‐substituted CC bond, [Ir(Py)(PCy3)(COD)]BArFgave higher conversion than catalyst 11. However, with several other substrates complex 11proved to be superior.

A synthetic route to tetradentate chiral N4ligands has been developed with the aim to study the potential of corresponding iron and manganese complexes as catalysts for enantioselective epoxidation. These ligands, which contain two oxazoline rings and two trialkylamino groups as coordinating units, are readily prepared in enantiomerically pure form by the reaction of chiral 2‐chloromethyloxazolines with achiral N,N′‐dimethylethane‐1,2‐diamine or chiral (R,R)‐N,N′‐dimethylcyclohexane‐1,2‐diamine. The ligands derived from N,N′‐dimethylethane‐1,2‐diamine reacted with anhydrous metal halides MnCl2and FeCl2in a stereoselective manner to give octahedral mononuclear complexes that have the general formula Δ‐[(L)MCl2]. In contrast, the ligands derived from N,N′‐dimethylcyclohexane‐1,2‐diamine formed complexes with different coordination modes depending on the diastereomer employed: in one case the metal ion was found to be pentacoordinate, in the other case a hexacoordinated complex was observed. The structure of a series of Fe and Mn complexes was determined by X‐ray analysis. The coordination chemistry of these ligands was further studied by X‐ray and NMR analyses of the diamagnetic isostructural complexes [(L)ZnCl2]. Analogous ionic complexes, which were prepared by removing chloride with silver trifluoromethanesulfonate or hexafluoroantimonate, were tested as catalysts for the epoxidation of olefins.

Iridium complexes derived from chiral phosphane–oxazolines (phox ligands) are efficient catalysts for intramolecular Pauson–Khand reactions. Under optimized conditions high yields and enantioselectivities of > 90 % ee were obtained with 2 mol-% of catalyst. The influence of the CO pressure and the anion were studied. The structure of a dicarbonyl(phox)iridium complex was determined by X-ray analysis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

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Enantiomerically pure iridium complexes with phosphino- and (phosphinooxy)-substituted N-heterocyclic carbene (NHC) ligands were synthesized. Investigation of their electronic properties showed a similar trans influence of the phosphino (or phosphinooxy) and the NHC units. The complexes were tested in iridium-catalyzed hydrogenation. While low conversions were observed with unfunctionalized olefins, the catalysts proved to be suitable for hydrogenation of the α,β-unsaturated ester 20, allylic alcohol 21, and imine 22. The enantioselectivities were, however, moderate.

Two libraries of enantiomerically pure imidazolium salts bearing an oxazoline unit were synthesized. Deprotonation of the imidazolium salts and complexation of the resulting oxazoline–carbene ligands to iridium(I) was achieved in one step by mixing the imidazolium salts with NaOtBu and [(η4‐cod)IrCl]2in THF at room temperature. The air‐stable complexes were purified by flash chromatography. All complexes were analyzed by two‐dimensional (2D) NMR methods and one compound from each family was characterized by X‐ray structure analysis. The two libraries of iridium complexes were successfully tested in the asymmetric hydrogenation of unfunctionalized and functionalized olefins. Enantioselectivities of up to 90 % eewere obtained with trans‐α‐methylstilbene. Upon complexation of imidazolium salt 15 pwith R1= phenyl, CH bond activation of the phenyl ring gave rise to iridium(III) complex 17, which was fully characterized by NMR spectroscopy and X‐ray structure analysis. Complex 17proved to be catalytically inactive in the hydrogenation.

Boron-bridged bisoxazoline (borabox) ligands have been used in the copper(II)-catalyzed benzoylation of pyridyl alcohols and 1,2-diols. Efficient kinetic resolution of 1,2-diols was achieved using both borabox and bisoxazoline (box) ligands. Borabox ligands induced high selectivities in the benzoylation of suitable pyridyl alcohols, where they outperformed bisoxazolines. In addition, highly enantioselective Cu(II)(borabox)-catalyzed benzoylation has been used for the synthesis of both enantiomers of a pyridyl alcohol.

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Two cationic rhodium(I)−tetrasilylene complexes, [Rh(SitBuNHC&dbd;CHNtBu)4]BArF (4; BArF = tetrakis[3,5-bis(trifluoromethyl)phenyl]borate) and [Rh(SitBuNH2C&dbd;CH2NtBu)4]BArF (5), were prepared from [Rh(cod)2]BArF and 1,3-di-tert-butyl-2,3-dihydro-1H-1,3,2-diazasilol-2-ylidene (1) or its saturated analogue 2, respectively (Figure 1). The two complexes were characterized by X-ray analysis and NMR spectroscopy. The crystal structures revealed a square-planar coordination geometry for both complexes. Only tetrakis(silylene) complexes were formed, even in the presence of less than 4 equiv of silylene.

The so-called sarcomatoid salivary duct carcinoma (SSDC) is one of the variants of salivary duct carcinoma (SDC). This neoplasm is characterized by the presence of both a carcinomatous and a sarcomatoid tumor component. The histology and nomenclature of such neoplasms has been a matter of debate for many years. The histologic, immunohistochemical, and electron microscopic findings including those of 4 previously described cases of SSDC are defined and the different attitudes concerning their etiology will be discussed. In addition, the fine-needle aspiration biopsy of such a case is presented for the first time. In analogy to typical SDC there seems to be a predilection for elderly men and a location in major salivary glands. The resected SSDC tumors measured between 1.5 and 3.5 cm. Histologically, each case was a composite of SDC and sarcomatoid carcinoma. Immunohistochemical positivity for epithelial membrane antigen (EMA) and cytokeratins (AE1/AE3, CAM 5.2) was shown in the sarcomatoid tumor component. The important cytomorphologic feature of SSDC is the presence of cohesive clusters and flat sheets of cells with a cribriform pattern, in combination with an atypical spindle cell component. The use of the term SSDC seems more appropriate than the term carcinosarcoma, as the immunohistochemical, electron microscopic, and recent molecular findings in this and other biphasic neoplasms imply a monoclonal origin.

Iridium complexes derived from chiral P,N ligands are efficient catalysts for the enantioselective hydrogenation of 2-aryl-substituted terminal alkenes. Using 0.1–1 4;mol 4;% of catalyst at room temperature and ambient hydrogen pressure, high enantioselectivities (88–94% ee), full conversions after short reaction times and essentially quantitative yields were obtained for a range of differently substituted 2-arylalkenes. Among six iridium complexes that were tested, the most selective catalyst was a complex with a phosphinite-oxazoline ligand derived from threonine (Ir-ThrePHOX). In contrast to the hydrogenation of trisubstituted alkenes, a strong pressure effect was observed for this class of substrates. Lowering the hydrogen pressure from 50 to 1 bar resulted in a strong increase of the ee values.

A series of N,P-ligands has been prepared, containing a chiral oxazoline ring and as a second chiral unit a bis(N-sulfonylamino)phosphine group embedded in a diazaphospholidine ring or a cyclic phosphite group derived from TADDOL. These modular ligands are readily synthesized from chiral amino alcohols and chiral 1,2-diamines or TADDOLs. Palladium and iridium complexes derived from these ligands were found to be efficient catalysts for enantioselective allylic alkylation and olefin hydrogenation, respectively.

In the asymmetric hydrogenation of unfunctionalized olefins with cationic iridium–PHOX catalysts, the reaction kinetics and, as a consequence, catalyst activity and productivity depend heavily on the counterion. A strong decrease in the reaction rate is observed in the series [Al{OC(CF3)3}4]−>BArF−>[B(C6F5)4]−>PF6−≫BF4−>CF3SO3−. With the first two anions, high rates, turnover frequencies (TOF>5000 h−1at 4 °C), and turnover numbers (TONs) of 2000–5000 are routinely achieved. The hexafluorophosphate salt reacts with lower rates, although they are still respectable; however, this salt suffers from deactivation during the reaction and extreme water‐sensitivity, especially at low catalyst loading. Triflate and tetrafluoroborate almost completely inhibit the catalyst. In contrast to the hexafluorophosphate salt, catalysts with [Al{OC(CF3)3}4]−, BArF−, and [B(C6F5)4]−as counterions do not lose activity during the reaction and remain active, even after all the substrate has been consumed. In addition they are much less sensitive to moisture and, in general, rigorous exclusion of water and oxygen is not necessary. A first‐order rate dependence on the hydrogen pressure was determined for the BArF−and the PF6−salts. At low catalyst loading, the rate dependence on catalyst concentration was also first order. The rate dependence on the alkene concentration was strikingly different for the two salts. While the reaction rate observed for the BArF−salt slightly decreased with increasing alkene concentration (rate order −0.2), a rate order of ≈1 was determined for the corresponding hexafluorophosphate at low alkene concentrations.

New Ir−SimplePHOX complexes Ir-6−Ir-9 catalyze the quantitative, highly enantioselective hydrogenation of a range of unfunctionalized and functionalized olefins. Synthesis, catalytic results, and X-ray crystal structures are presented here.