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Asymmetric three‐component, 1,2‐aminoxy‐trifluoromethylation of styrenes with N‐hydroxy‐1,3‐benz/naphthoxazine‐2,4‐diones (i. e. N‐OH‐(B/Np)OxzOn) catalysed by chiral vanadyl complexes derived from N‐salicylidene‐L‐t‐leucinate were explored. Among 14 different solvents and 13 different catalysts screened, the best reaction scenarios were in 2‐propanol with 3‐(2,5‐dimethyl)phenyl‐5‐bromo (DMP), or 3‐t‐butyl‐5‐bromo substituted catalysts that led to the corresponding complementary (R)‐ and (S)‐products with potential biological activities in 45–91% yields and up to 85 and 75% ee, respectively. Further optimisation with the DMP catalyst led to the best combination of 3‐halo/3,5‐dihalo‐styrenes with 6‐/7‐Br−N−OH‐(B/Np)OxzOn as the trapping agents. The corresponding eight different products were isolated in 52–75% yields with ees in a range of 88–93% (R). Based on Density Functional Theory (DFT) calculations with conformational searches, the origin of enantiocontrol and the working mechanism were proposed by resorting to a bidentate‐chelation between the amide or carbamate C=O group and N−OH group in the trapping agent to the vanadyl center followed by asymmetric benzylic radical trapping in an SH2 fashion. Subsequent Fragment Molecular Orbital (FMO)/Pair Interaction Energy Decomposition Analysis (PIEDA) calculations with the DMP catalyst were carried out to rationalize the extent of asymmetric induction. One representative product derived from p‐methyl‐styrene and NpOxzOn was hydrolyzed in basic MeOH with decarboxylation to unmask its carbamate moiety. The resulting chiral (R)‐N‐benzoxy‐3‐hydroxy‐2‐naphthamide was subjected to aerobic, oxidative homo‐coupling catalysed by the DMP catalyst in CCl4. The corresponding 2,2‐binaphthol product was isolated in 90% (brsm) yield with nearly complete diastereo‐control at the created (M)‐axial chirality, allowing for sequential, bi‐functional asymmetric cross‐coupling applications. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms that maintain microbial biodiversity is a critical aspiration in ecology. Past work on microbial coexistence has largely focused on species pairs, but it is unclear whether pairwise coexistence in isolation is required for coexistence in a multispecies community. To address this question, we conducted hundreds of pairwise competition experiments among the stably coexisting members of 12 different enrichment communities in vitro. To determine the outcomes of these experiments, we developed an automated image analysis pipeline to quantify species abundances. We found that competitive exclusion was the most common outcome, and it was strongly hierarchical and transitive. Because many species that coexist within a stable multispecies community fail to coexist in pairwise co-culture under identical conditions, we concluded that multispecies coexistence is an emergent phenomenon. This work highlights the importance of community context for understanding the origins of coexistence in complex ecosystems. [ABSTRACT FROM AUTHOR]

We report the synthesis of a new palladium complex (1a) bearing two different P-donors, di(1-adamantyl)phosphinous acid and triphenylphosphine. A heteroleptic complex with a phosphinous acid ligand has rarely been reported. With phenyl bromide and di-p-tolylphosphine oxide as reagents, PPh3-stabilised 1a was proved to be a noteworthy Pd(II) precatalyst for carbon-phosphorus bond formation. 1a-catalysed Hirao coupling could be efficiently made in environmentally benign ethanol. Reacting for 10 to 120 minutes, aryl bromides equipped with electron-donating or electron-withdrawing groups were successfully catalysed. Nucleophile-sensitive 2-bromopyridine, 2-bromothiophene, and 4-bromobenzonitrile were applicable in toluene/ethylene glycol (EG) (9/1). 1a-catalyzed Hirao coupling was successfully applied to the synthesis of a host material in an organic light-emitting diode (OLED) and precursor of biarylphosphines. A mechanistic study regarding how plausible Pd(0) active species are generated was jointly investigated by means of DFT calculation, ESI mass spectroscopy, and experiment. Interestingly, we demonstrated a proof of concept that bulky di(1-adamantyl)phosphine oxide is a useful preligand and less bulky di-p-tolylphosphine oxide is the substrate in the Hirao coupling. [ABSTRACT FROM AUTHOR]

Several 2-substituted (H, Ph, and S-Me) and 1-substituted (H, Ph, and Bn), 3-hydroxy-1,3-quinazolin(di)ones were utilized for the first time as radical trapping agents in asymmetric 1,2-oxytrifluoromethylation of styrenes catalyzed by chiral vanadyl methoxide complexes bearing 3,5-disubstituted-N-salicylidene-t-leucinate templates. The effects of catalysts and solvents on the asymmetric induction were systematically examined. The best and complementary scenarios involved the use of vanadyl complexes V(O)-1 and V(O)-2, which bear 3-(2,5-dimethyl)phenyl-5-bromophenyl and 3-t-butyl-5-bromophenyl groups in an i-propanol solvent at ambient temperature. The corresponding (R)-cross-coupling products by V(O)-1 were obtained in 45–71% (for 2-substituted series) and 59–93% yields (for 1-substituted series) for p-/m-methylstyrenes and m-halo/CF3/CO2Me-styrenes in 38–63% ees (the best in 2-H case) and 60–84% ees (the best in 1-benzyl cases), respectively. The corresponding (S)-cross-coupling products by V(O)-2 were obtained in 28–55% (for 2-substituted series) and 45–72% yields (for 1-substituted series) for the same substrate class in 50–91% ees (85–91% ees in 2-phenyl cases) and 64–75% ees (up to 74–75% ees for each 1-H, Ph, and Bn cases), respectively. Theoretical calculations were carried out to explain the origin and extent of enantiocontrols. They both may serve as potential inhibitors of acetohydroxyacid synthase and epidermal growth factor receptor (EGFR) kinases. [ABSTRACT FROM AUTHOR]

In this study, two (HO)R2P→Pd(II)Cl2←NHC precatalysts (1 s) were designed and synthesized. Using these precatalysts, unreactive aryl chlorides, benzyl chlorides, or benzoyl chlorides were highly efficiently converted to the desired products in three to tens of minutes at 35 °C. Upon deprotonation of 1 s, density‐functional theory calculations and electrospray ionization mass spectrometry revealed that NHC was dissociated from the deprotonated precatalysts. Although it is difficult to ascertain the NHC dissociated from Pd(II) or Pd(0) species, the proposed anionic (O−)R2P→Pd(II)Cl2 species could be reduced using ethoxide to form Pd(0) catalytic species. The cation and anion functions of salt additives were systematically elucidated. The cation size could be used to modulate the catalytic properties of 1 s through outer‐sphere electrostatic interactions between the coordinated R2P(O−) and alkali metal ions. Moreover, the basicity of base was proportional to the catalytic yields. This study introduces newly designed Pd(II) precatalysts with superb catalytic properties that are stable and remarkably efficient. [ABSTRACT FROM AUTHOR]

Patients with immune-mediated inflammatory diseases (IMID) were seldom enrolled in the studies of SARS-CoV-2 vaccines, and real-world data regarding the immunogenicity of different types of vaccines is limited. We aimed to assess the immunogenicity and safety of three types of vaccines (AZD1222, mRNA-1273, and BNT162b2) in 253 patients with IMID and 30 healthcare workers (HCWs). Plasma levels of IgG-antibody against SARS-CoV-2 targeting the receptor-binding domain of spike protein (anti-S/RBD-IgG) were determined by chemiluminescent immunoassay 3–4 weeks after the first-dose and second-dose vaccination. The positive rate and titers of anti-S/RBD-IgG were significantly higher in mRNA-1273 or BNT162b2 than in the AZD1222 vaccine. Immunogenicity was augmented after the second dose of any vaccine type in all IMID patients, suggesting that these patients should complete the vaccination series. Anti-S/RBD-IgG titers after first-dose vaccination were significantly lower in RA patients than pSS patients, but there was no significant difference after second-dose vaccination among five groups of IMID patients. The positive rate and titers of anti-S/RBD-IgG were significantly lower in patients receiving abatacept/rituximab therapy than in those receiving other DMARDs. All three SARS-CoV-2 vaccines showed acceptable safety profiles, and the common AEs were injection site reactions. We identified SLE as a significant predictor of increased autoimmunity and would like to promote awareness of the possibility of autoimmunity following vaccination. [ABSTRACT FROM AUTHOR]

Microbial communities frequently invade one another as a whole, a phenomenon known as community coalescence. Despite its potential importance for the assembly, dynamics, and stability of microbial consortia, as well as its prospective utility for microbiome engineering, our understanding of the processes that govern it is still very limited. Theory has suggested that microbial communities may exhibit cohesiveness in the face of invasions emerging from collective metabolic interactions across microbes and their environment. This cohesiveness may lead to correlated invasional outcomes, where the fate of a given taxon is determined by that of other members of its community--a hypothesis known as ecological coselection. Here, we have performed over 100 invasion and coalescence experiments with microbial communities of various origins assembled in two different synthetic environments. We show that the dominant members of the primary communities can recruit their rarer partners during coalescence (top-down coselection) and also be recruited by them (bottom-up coselection). With the aid of a consumer-resource model, we found that the emergence of top-down or bottom-up cohesiveness is modulated by the structure of the underlying cross-feeding networks that sustain the coalesced communities. The model also predicts that these two forms of ecological coselection cannot co-occur under our conditions, and we have experimentally confirmed that one can be strong only when the other is weak. Our results provide direct evidence that collective invasions can be expected to produce ecological coselection as a result of cross-feeding interactions at the community level. [ABSTRACT FROM AUTHOR]

Malaria is an infectious disease caused by Plasmodium parasites that are mainly transmitted through the bites of infected female Anopheles mosquitoes. The average annual number of malaria cases was less than ten in Taiwan in the last five years. Most of the cases were caused by Plasmodium vivax and Plasmodium falciparum, and were primarily diagnosed in travelers who returned from Southeast Asia and Africa. Here, we report the first case of Plasmodium ovale infection within five years that was confirmed by peripheral blood smear examination and molecular identification in a 25-year-old Asian female patient who returned from Uganda. [ABSTRACT FROM AUTHOR]

Six four-coordinated complexes of the chemical formulae [Hg(2-N CH2COOCH2CH3-21-H-NCTPP)X] with X = Cl (5), Br (6), I (7), [Hg(2-NCH3-21-H-NCTPP)Cl] (4) and [Hg(2-NCH2COOCH2C6H5-21-H-NCTPP)X] with X = Cl (8), I (9) are synthesized and structurally determined. The bond path for the weak η1-H(17)–C(17)…Hg agostic interactions between the Hg center and H(17) in complexes 4–9 was a through-space interaction from Hg to agostic carbon [C(17)] followed by a through-bond interaction from C(17) to an agostic proton [H(17)]. The magnitude of J[Hg–H(17)] [or the agostic upfield shift Δδago of the C(17)] for these complexes increases as the halide ligand varies from iodide to chloride, ranging from 33.2 Hz (or 14.3 ppm) for I− to 36 Hz (or 15.8 ppm) for Br− and 36.9 Hz (or 16.0 ppm) for Cl−. The plot of J[Hg–H(17)] for the agostic proton H(17) versus☋Δδago☋ for the agostic carbon atom C(17) in compounds 3–9 was linearly expressed as J[Hg–H(17)] = 2.29 ☋Δδago☋ + 0.13. [ABSTRACT FROM AUTHOR]

The one-pot synthesis of 2,5-bis(diarylphosphoryl)-3,6-bis(arylamino)cyclohexa-2,5-diene-1,4-diones has been achieved by AgI-mediated full C-H functionalization of 1,4-benzoquinone (BQ) through regioselective dual phosphination and amination reactions. BQ, diarylphosphine oxides [SPOs, Ar2PH(=O)], and imines reacted to give the products under mild conditions. 1,4-Naphthoquinone (NQ) could also be used instead of BQ. When aniline was used instead of the corresponding imine, a lower yield of the desired product was obtained. In the absence of Ag2CO3, hydrophosphinylation of the imine by the SPO occurred as a competitive side-reaction. AgI plays versatile roles in this reaction, as a mediator for facilitating the consecutive additions of Ar2P(=O)- and aniline to the related β-carbon atoms of BQ, as an oxidant of hydroquinone (HQ) intermediates to form the substituted BQ counterpart, and as an inhibitor of the hydrophosphinylation side-reaction of the imine by the SPO. The X-ray crystal structures of several new products have been determined. A reaction mechanism is also proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

Facial nerve palsy involves a wide spectrum of etiologies. The most common cause of peripheral facial palsy is Bell’s palsy. Facial nerve neoplasm is a rare cause of facial palsy. A 56-year-old male patient presented with a gradual onset of peripheral-type right facial palsy and with a finding of facial nerve mastoid segment tumor by magnetic resonance imaging. Surgical exploration showed no tumor tissue, but there was granulation surrounding a segment of an atrophic facial nerve. Pathology revealed fibrosis mixed with granulation, and virologic analysis was negative for herpes simplex virus. Facial palsy is a challenging issue. Suspicion of a facial neoplasm at a rare location and isolated segment raised the differential diagnosis of uncommon facial nerve lesions. Surgical exploration could not categorize the lesion into infection, neoplasm, or trauma. Further studies on similar patients may define this as a completely new disease in the future. [ABSTRACT FROM AUTHOR]

Several new amino-type secondary phosphine oxide (SPO) pre-ligands (3a-3h) that contain P-N bonds were synthesized and characterized. SPOs 3a-3h can tautomerize to phosphinous acids (PA, 3a-3h) as genuine ligands. The formation of SPOs 3a-3h occurred first through nucleophilic attack on the imine carbon atom, then by the addition of RPCl2 (R = Ph, Cy, τBu, or iPr), and work-up under acidic conditions. The P-N bond in the newly prepared SPOs is evident from the crystal structures of SPOs 3d and 3h. Reactions of SPOs 3f, 3g,or 3h with Pd(COD)Cl2 (COD = cyclooctadiene) yielded palladium complexes 6f, 6g,or 6h. In these crystal structures, PAs 3f, 3g, and 3h act as didentate ligands through P and N donors. Intriguingly, the reaction of SPO 3f with Pd(COD)Cl2 also gave rise to palladium complexes 7fa, 7fb, and 8f. The crystal structures of 7fa and 7fb show that the palladium atom is chelated by PA 3f and coordinated by a phosphine-like ligand fragmented from SPO 3f through C--N bond dissociation. Finally, the syntheses of carbazole derivatives were pursued in Catellani reactions with SPOs 3g and 3h as pre-ligands. A mechanism is proposed to account for the catalytic reaction (see the Supporting Information). The optimized conditions for Suzuki reactions using selected SPO ligands are also reported. [ABSTRACT FROM AUTHOR]

A series of cyclohexane-1,2-diamine ( 3a- 3d) and benzene-1,2-diamine derivatives ( 3e- 3h) were pre- pared. Followed by hydrolysis, the reaction of 3a- 3c with PCl3 successfully led to the formation of cor- responding metastable saturated heteroatom-substituted secondary phosphine oxides (HASPO 4a- 4c), a tautomer of the saturated heteroatom-substituted phosphinous acid (HAPA). Whereas ambient-stable diamine-coordinated palladium complexes were obtained, HAPA-coordinated palladium complexes were not successfully synthesized. The molecular structures of HASPO 4c, Pd(OAc)2(3a), PdBr2(3b) and Pd(OAc)2(3c) and [Cu(NO3)(3d)+][NO3 − ] were determined by single-crystal X-ray diffraction method. Catalysis of in-situ Suzuki-Miyaura cross-coupling reactions for aryl bromides and phenylboronic acid using diamine 3a as ancillary ligand showed that the optimized reaction condition at 60 °C is the combination of 2 mmol % 3a/3.0 mmol KOH/1.0 mL 1,4-dioxane/1 mmol % Pd(OAc)2. Moreover, moderate reactivity was observed when using aryl chlorides as substrates (supporting infor- mation). When diamine 3d was employed in Heck reaction, good tolerance of functional groups of aryl bromides were observed while using 4-bromoanisole and styrene as substrates. The optimized condi- tion for Heck reaction at 100 °C is 3 mmol % 3d/3.0 mmol CsF/1.0 mL toluene/3 mmol % Pd(OAc)2. In general, cyclohexane-1,2-diamine derivatives exhibited better catalytic properties than those of benzene-1,2-diamines. [ABSTRACT FROM AUTHOR]

The inner C-benzyl- and C-o-xylyl (or m-xylyl, p-xylyl)-substituted cobalt(ii) complexes of a 2-N-substituted N-confused porphyrin were synthesized from the reaction of 2-NC3H5NCTPPH (1) and CoCl2·6H2O in toluene (or o-xylene, m-xylene, p-xylene). The crystal structures of diamagnetic chloro(2-aza-2-allyl-5,10,15,20-tetraphenyl-21-hydrogen-21-carbaporphyrinato-N,N′,N′′)zinc(ii) [Zn(2-NC3H5-21-H-NCTPP)Cl; 3 ] and paramagnetic chloro(2-aza-2-allyl-5,10,15,20-tetraphenyl-21-benzyl-21-carbaporphyrinato-N,N′,N′′)cobalt(ii) [Co(2-NC3H5-21-CH2C6H5NCTPP)Cl; 7], and chloro(2-aza-2-allyl-5,10,15,20-tetraphenyl-21-Y-xylyl-21-carbaporphyrinato-N,N′,N′′)cobalt(ii) [Co(2-NC3H5-21-Y-CH2C6H4CH3NCTPP)Cl] [Y = o (8), m (9), p (10)] were determined. The coordination sphere around the Zn2+ (or Co2+) ion in 3 (or 7–10) is a distorted tetrahedron (DT). The free energy of activation at the coalescence temperature Tc for the exchange of phenyl ortho protons o-H (26) with o-H (22) in 3 in a CDCl3 solvent is found to be ΔG‡293 = 61.4 kJ mol−1 through 1H NMR temperature-dependent measurements. The axial zero-field splitting parameter ☋D☋ was found to vary from 35.6 cm−1 in 7 (or 30.7 cm−1 in 8) to 42.0 cm−1 in 9 and 46.9 cm−1 in 10 through paramagnetic susceptibility measurements. The magnitude of ☋D☋ can be related to the coordination sphere at the cobalt sites. [ABSTRACT FROM AUTHOR]

Thionation and fluorination of pyromellitic diimides (PyDIs) increased the electron mobility and on/off ratio of the original diimides by two orders of magnitude and improved the threshold voltage and air-stability of diimide compounds. [ABSTRACT FROM AUTHOR]

A new route to the direct preparation of H-phosphinate esters has been explored. The ring-opening reaction of cyclic ether (tetrahydrofuran or tetrahydropyrane) was carried out with magnesium halide in the presence of phosphine halide (PRCl2 or PCl3). The process is straightforward and all the reagents are relatively cheap and readily available. Magnesium halide-mediated THF ring-opening (SN2@C) and the subsequent SN2@P elementary reactions that giving rise to the intermediate of haloalkyl phosphinates have been discussed based on our experimental findings ( Path I: SN2@C−+SN2@P). Another possible route, the direct SN2 between THF (nucleophile) and phosphine halide (electrophile) that followed by THF ring opening by halide dissociated from phosphine halide ( Path II: SN2@P−+SN2@C), was also proposed. However, path II is the least likely reaction path because neutral THF is not a good nucleophile. H-phosphinate esters could be readily available in the subsequent hydrolysis process. Considering the ionic bond strength in magnesium halides and the nucleophilicity of halides dissociated from MgX2 in protic solvents like water, MgBr2 is recommended for ring-opening reactions of cyclic ethers. [ABSTRACT FROM AUTHOR]

A ball screw is a typical mechanical part that experiences wear-out and is widely used in computer numerical control machine tools to control the movement of processing targets and spindles. These types of parts need frequent checks so that they are replaced before excessive wear occurs. Until now, there was no simple way to measure directly the state of wear quantitatively. An indirect approach is logging the signals (vibration, temperature, and preload change) during the operation of mechanical parts. This information can be used to construct a wear model for estimating its remaining lifetime. For embedding sensors into mechanical devices, wireless sensors bring advantages in that they may be installed freely without constraints from data or power cables. However, wireless transmission is subjected to interference. To make wireless sensors that can be used practically within an industrial environment, we propose a wireless sensor system that: 1) emphasizes low-power and low cost in hardware design; 2) logs the signals during the operation of a mechanical part that could experience wear; and 3) guarantees that all the logged data can be wirelessly delivered to the data server. To our knowledge, this is the first wireless sensor system for measurement of mechanical operation signals that guarantees complete data delivery and correctness. We designed, implemented, and evaluated this system in real environments. This ensures that the design is practical. We envision that a miniature version of our design could be embedded in the ball screw shaft and gearbox reducer for logging signals to enable the building of a wear model to estimate the part's lifetime. [ABSTRACT FROM PUBLISHER]