Compounds containing sulfonyl‐derived functional groups have received intensive attention owing to their widespread applications in life science, pharmaceuticals and materials science. To access this ...type of compounds, the multi‐component sulfonylation reactions relying on sulfur dioxide (SO2) insertion strategy have emerged as novel and attractive approaches in the past decade. The utilization of SO2 surrogates for SO2 insertion in the multicomponent reactions (MCRs) have improved reaction flexibility and step economy. Moreover, some advances have been achieved in the challenging but practical asymmetric MCRs for the construction of high value‐added chiral sulfones. This review aims to summarize the progress made in the MCRs involving SO2 surrogates from 2019 to 2022, and point out the potentials and challenges in this field.
Multicomponent reactions (MCRs) have become popular tools for the efficient generation of sulfonyl‐containing molecules. Compared with gaseous SO2, the solid and stable sulfur dioxide surrogates are more convenient to handle. This significantly promotes the development of multi‐component sulfonylation reactions, and some advances have been achieved in the asymmetric MCRs for the construction of high value‐added chiral sulfones.
The evaluation of childhood trauma is essential for the treatment of schizophrenia. The short form of Childhood Trauma Questionnaire (CTQ-SF) is a widely used measure of the experience of childhood ...trauma in the general population. Nevertheless, data regarding the psychometric property of CTQ-SF for assessing childhood trauma of patients with schizophrenia are very limited.
Two hundred Chinese inpatients with schizophrenia completed the Chinese CTQ-SF, the Child Psychological Maltreatment Scale (CPMS), the Impact of Events Scale-Revised (IES-R), and the Dissociative Experiences Scale-II (DES-II). To assess test-retest reliability of the CTQ-SF, all patients completed the CTQ-SF again two weeks later. Concurrent and convergent validity was assessed by analyzing Pearson bivariate correlation coefficients between CTQ-SF and CPMS, IES-R, and DES-II.
The Cronbach's α coefficient of the Chinese CTQ-SF was 0.81, and the two-week re-test reliability was 0.81 (P<0.01). The criterion-related validity coefficients of CTQ-SF with the CMPS, IES-R and DES-II were 0.61, 0.41, and 0.51, respectively.
The Chinese CTQ-SF has satisfactory psychometric properties to measure childhood abuse or neglect in Chinese inpatients with schizophrenia.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A method for direct access to enantioenriched benzylic amides and carbamate‐protected primary benzylamines by C−H functionalization is reported. The C−H substrate is used as limiting reagent with ...only a small excess of the unactivated amide or carbamate nucleophile. The enantioselective intermolecular dehydrogenative C−N bond formation is enabled by a combination of a chiral copper catalyst, a photocatalyst, and an oxidant, and it takes place under mild conditions, which allow for a broad substrate scope. The method is compatible with late‐stage C−H functionalization, and it provides easy access to 15N‐labeled amides and amines starting from cheap 15NH4Cl.
A method for enantioselective intermolecular benzylic C−H amidation and amination is reported. This dehydrogenative C−N bond formation displays broad substrate scope and good atom economy, is amenable to late‐stage C−H functionalization, and enables easy access to 15N‐labeling from cheap 15N‐NH4Cl.
Abstract
We present a time-resolved spectral analysis of bright X-ray flares observed by Swift X-ray telescope from 2004 December to 2021 December. We selected 58 bright flares from 56 gamma-ray ...burst X-ray afterglows to perform time-resolved spectral analysis. We find that there is a strong spectral evolution in X-ray flares. Spectral evolution exists in all the X-ray flares. We have not found flares without spectral evolutions in our samples. The spectrum of an X-ray afterglow is dominated by the flare when it exists. Four spectral evolution patterns were found, i.e., hard-to-soft, intensity tracking, soft-to-hard, and anti-intensity tracking. Most of the flares (46 flares, 79.3%) show a spectral evolution from hard to soft. Five (8.6%) flares are intensity tracking. Two (3.5%) flares show soft-to-hard. Five (8.6%) flares show anti-intensity tracking. Therefore, hard-to-soft spectral evolution patterns dominate the spectral evolutions of X-ray flares. In other words, the hard-to-soft spectral evolution pattern is the main evolution pattern of X-ray flares. Hard-to-soft, intensity tracking, and soft-to-hard spectral evolution patterns are the same as prompt emission spectral evolutions, indicating that the origin of flares should be the same as prompt emissions and the flares are the lower energy band emissions of the prompt emissions. The spectral evolution intensities are independent of the peak time and FWHM of the flares. In other words, the spectral evolution intensity is irrelevant to the flare occurrence time and its duration but related to the peak fluxes of flares. This means that the more luminous the flares, the stronger the spectral evolutions.
An extremely stable hydrogen-bonded organic framework, HOF-8, was fabricated. HOF-8 is not only thermally stable but also stable in water and common organic solvents. More interestingly, desolvated ...HOF-8 exhibits high CO2 adsorption as well as highly selective CO2 and C6H6 adsorption at ambient temperature.
A nickel‐catalyzed aryl thioether metathesis has been developed to access high‐value thioethers. 1,2‐Bis(dicyclohexylphosphino)ethane (dcype) is essential to promote this highly ...functional‐group‐tolerant reaction. Furthermore, synthetically challenging macrocycles could be obtained in good yield in an unusual example of ring‐closing metathesis that does not involve alkene bonds. In‐depth organometallic studies support a reversible Ni0/NiII pathway to product formation. Overall, this work not only provides a more sustainable alternative to previous catalytic systems based on Pd, but also presents new applications and mechanistic information that are highly relevant to the further development and application of unusual single‐bond metathesis reactions.
Ch‐ch‐change S: A nickel‐catalyzed aryl thioether metathesis with high functional‐group tolerance was developed, with bis(dicyclohexylphosphino)ethane (dcype) being essential to promote the reaction. Synthetically challenging macrocycles were obtained in good yield in an unusual example of ring‐closing metathesis that does not involve alkene bonds. In‐depth organometallic studies support a reversible Ni0/NiII pathway to product formation.
ABSTRACT X-ray flares are generally supposed to be produced by later activities of the central engine, and may share a similar physical origin with the prompt emission of gamma-ray bursts (GRBs). In ...this paper, we have analyzed all significant X-ray flares from the GRBs observed by Swift from 2005 April to 2015 March. The catalog contains 468 bright X-ray flares, including 200 flares with redshifts. We obtain the fitting results of X-ray flares, such as start time, peak time, duration, peak flux, fluence, peak luminosity, and mean luminosity. The peak luminosity decreases with peak time, following a power-law behavior . The flare duration increases with peak time. The 0.3-10 keV isotropic energy of the distribution of X-ray flares is a log-normal peaked at erg. We also study the frequency distributions of flare parameters, including energies, durations, peak fluxes, rise times, decay times, and waiting times. Power-law distributions of energies, durations, peak fluxes, and waiting times are found in GRB X-ray flares and solar flares. These distributions could be well explained by a fractal-diffusive, self-organized criticality model. Some theoretical models based on magnetic reconnection have been proposed to explain X-ray flares. Our result shows that the relativistic jets of GRBs may be dominated by Poynting flux.
Due to the sparsity of space probes, it is still not clear on how the magnetic structure of the magnetotail looks like and how it evolves when the interplanetary magnetic field (IMF) directs ...northward. This simulation study uses two different global magnetosphere magnetohydrodynamics (MHD) models to simulate two northward IMF events and study the evolution of the magnetotail. Both models show that the magnetotail may form a structure that is composed of a dawnside tail lobe and a duskside tail lobe, under northward IMF conditions with significant By, instead of a northern tail lobe and a southern tail lobe under southward IMF conditions. In this magnetic configuration, a tail lobe extends a domain from northern (southern) cusp to southern (northern) IMF. The larger the magnitude of IMF clock angle, the longer and wider the magnetotail. Such magnetic configuration suggests that magnetotail reconnection is possible to occur when the dawnside tail lobe contacts with the duskside tail lobe and thus a substorm is also possible to occur under northward IMF conditions with significant By.
Plain Language Summary
The Earth's magnetosphere is a vast space with certain magnetic structure and plasma material and is directly affected by solar wind and its embedded magnetic field named interplanetary magnetic field (IMF). Due to the sparsity of space probes, it is still not clear on how the magnetic structure of the magnetosphere looks like and how it evolves, especially when the IMF arriving the magnetosphere directs northward with a significant dawn‐dusk component, By. This simulation study uses two different global magnetosphere models to simulate the magnetosphere for two periods with northward IMF and show that the magnetotail (tail of magnetosphere) may form a structure that is composed of a dawnside tail lobe and a duskside tail lobe instead of a northern tail lobe and a southern tail lobe under southward IMF conditions. In this magnetic configuration, a tail lobe extends a domain from northern (southern) cusp to southern (northern) IMF. The larger the IMF By, the longer and wider the magnetotail. Such magnetic configuration suggests that magnetotail reconnection is possible to occur when the dawnside tail lobe contacts with the duskside tail lobe, and thus a substorm is also possible to occur under northward IMF conditions with significant By.
Key Points
A dawnside tail lobe and a duskside tail lobe may form in the magnetotail under northward interplanetary magnetic field (IMF) conditions with significant By
The larger the magnitude of IMF clock angle, the longer and wider the magnetotail
Magnetotail reconnection may occur when the dawnside tail lobe contacts with the duskside tail lobe, and is possible to cause substorm
Cross‐electrophile coupling reactions are efficient for the construction of carbon‐carbon bonds under relatively mild conditions, and hence widely used for making new molecules. Among various ...electrophiles, the cross‐electrophile coupling reaction between two different tosylates has been rarely studied. Herein, we present a cross‐electrophile coupling of gem‐difluoroalkenyl tosylate (C(sp2)−OTs) and α‐CF3 benzyl tosylate (C(sp3)−OTs) by nickel/palladium cooperative catalysis. Mechanistic investigation indicated that the activation of C(sp2)−OTs bond and C(sp3)−OTs bond was facilitated by nickel and palladium respectively.
A cross‐electrophile coupling reaction of gem‐difluoroalkenyl tosylate with α‐CF3 benzyl tosylate is presented. This protocol is the first example of cross‐electrophile coupling between two different tosylates by Pd/Ni cooperative catalysis.
Compounds bearing aryl-sulfur and aryl-phosphorus bonds have found numerous applications in drug development, organic materials, polymer science, and homogeneous catalysis. We describe ...palladium-catalyzed metathesis reactions of both compound classes, each of which proceeds through a reversible arylation manifold. The synthetic power and immediate utility of this approach are demonstrated in several applications that would be challenging to achieve by means of traditional cross-coupling methods. The C(sp²)–S bond metathesis protocol was used in the depolymerization of a commercial thermoplastic polymer and in the late-stage derivatization of a drug. The C(sp²)–P variant led to the convenient preparation of a variety of phosphorus heterocycles, including a potential chiral ligand and fluorescent organic materials, via a ring-closing transformation.
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