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In contrast with the well‐established C(sp2)−SCF3 cross‐coupling to forge the Ar−SCF3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp3)−SCF3 bond has remained largely unexplored. We herein disclose a copper‐catalyzed enantioselective radical C(sp3)−SCF3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me4N)SCF3 reagent. The key to the success lies in the utilization of chiral phosphino‐oxazoline‐derived anionic N,N,P‐ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp3)−SCF3 cross‐coupling of racemic benzyl halides and three‐component 1,2‐carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF3‐containing molecules of interest in organic synthesis and medicinal chemistry. [ABSTRACT FROM AUTHOR]

In contrast with the well‐established C(sp2)−SCF3 cross‐coupling to forge the Ar−SCF3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp3)−SCF3 bond has remained largely unexplored. We herein disclose a copper‐catalyzed enantioselective radical C(sp3)−SCF3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me4N)SCF3 reagent. The key to the success lies in the utilization of chiral phosphino‐oxazoline‐derived anionic N,N,P‐ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp3)−SCF3 cross‐coupling of racemic benzyl halides and three‐component 1,2‐carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF3‐containing molecules of interest in organic synthesis and medicinal chemistry. [ABSTRACT FROM AUTHOR]

The enantioconvergent radical Suzuki–Miyaura cross-coupling of racemic alkyl halides represents a powerful approach for the construction of valuable C(sp3)–C bonds. In this regard, the earth-abundant first-row transition metal (Ni, Fe, Co, and Cu) catalyst possesses a good single-electron transfer ability and can easily convert racemic alkyl halides to the prochiral alkyl radicals, providing an ideal solution for enantioconvergence. The utilization of chiral ligands would further facilitate the realization of enantioselective control over the prochiral alkyl radicals. This Perspective will discuss the advances and anticipate further development in this burgeoning field. [ABSTRACT FROM AUTHOR]

In this study, the reaction interfaces of four kinds of oxide refractories (corundum, spinel, mullite, and zirconia) with lanthanum oxide (La2O3) and lanthanum aluminate (LaAlO3) under different atmospheres at high temperatures (1550°C) were analyzed. The results show that the four oxides have a strong reaction with La2O3, and the corresponding rare earth aluminate, rare earth silicate, and rare earth zirconate are formed respectively. The reaction with LaAlO3 is weak, and almost no reaction occurs. Mullite has poor structural stability in a high‐temperature reduction atmosphere, easy decomposition, and strong reaction with La2O3. This study provides an important reference for the study of the reaction mechanism between rare earth steel and lining materials and the research and development of special lining materials for rare earth steel. [ABSTRACT FROM AUTHOR]

In contrast with the well‐established C(sp2)−SCF3 cross‐coupling to forge the Ar−SCF3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp3)−SCF3 bond has remained largely unexplored. We herein disclose a copper‐catalyzed enantioselective radical C(sp3)−SCF3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me4N)SCF3 reagent. The key to the success lies in the utilization of chiral phosphino‐oxazoline‐derived anionic N,N,P‐ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp3)−SCF3 cross‐coupling of racemic benzyl halides and three‐component 1,2‐carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF3‐containing molecules of interest in organic synthesis and medicinal chemistry. [ABSTRACT FROM AUTHOR]

In contrast with the well‐established C(sp2)−SCF3 cross‐coupling to forge the Ar−SCF3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp3)−SCF3 bond has remained largely unexplored. We herein disclose a copper‐catalyzed enantioselective radical C(sp3)−SCF3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me4N)SCF3 reagent. The key to the success lies in the utilization of chiral phosphino‐oxazoline‐derived anionic N,N,P‐ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp3)−SCF3 cross‐coupling of racemic benzyl halides and three‐component 1,2‐carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF3‐containing molecules of interest in organic synthesis and medicinal chemistry. [ABSTRACT FROM AUTHOR]

The residual amount of halogenated solvents in olive oil is an important indicator of its quality. The National Olive Oil Quality Standard GB/T 23347-2021 states that the residual amount of individual halogenated solvents in olive oil should be ≤0.1 mg/kg and that the total residual amount of halogenated solvents should be ≤0.2 mg/kg. COI/T.20/Doc. No. 8-1990, which was published by the International Olive Council, describes the standard method used for the determination of halogenated solvents in olive oil. Unfortunately, this method is cumbersome, has poor repeatability and low automation, and is unsuitable for the detection and analysis of residual halogenated solvents in large quantities of olive oil. At present, no national standard method for determining residual halogenated solvents in olive oil is available in China. Thus, developing simple, efficient, accurate, and stable methods for the determination of residual halogenated solvents in olive oil is imperative. In this paper, a method based on automatic headspace gas chromatography was established for the determination of residual halogenated solvents, namely, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, dibromochloromethane, tetrachloroethylene, and bromoform, in olive oil. The samples were processed as follows. After mixing, 2.00 g (accurate to 0.01 g) of the olive oil sample was added into a 20 mL headspace injection bottle and immediately sealed for headspace gas chromatography analysis. Blank virgin olive oil was used to prepare a standard working solution and the external standard method for quantification. The solvents used in the preparation of halogenated solvent standard intermediates were investigated and methanol was selected as a replacement for N , N -dimethylacetamide to prepare a halogenated solvent standard intermediate owing to its safety. The effects of different injection times (1, 2, 3, 4, 5, 6 s), equilibration temperatures (60, 70, 80, 90, 100, 110, 120 ℃), and equilibration times (4, 5, 8, 10, 20, 30, 40 min) of the headspace sampler on the detection of the residual amounts of the six halogenated solvents were investigated. The optimal injection time and equilibration temperature were 3 s and 90 ℃, respectively. The method demonstrated good analytical performance for the six halogenated solvents when the equilibration time was 30 min. A methodological study was conducted on the optimized method, and the results showed that the six halogenated solvents exhibited good linear relationships in the range of 0.002-0.200 mg/kg, with correlation coefficients of ≥0.9991. The limits of detection (LODs) and quantification (LOQs) of 1,1,1-trichloroethane and bromoform were 0.0006 and 0.002 mg/kg, respectively. The LODs and LOQs of chloroform, carbon tetrachloride, dibromochloromethane, and tetrachloroethylene were 0.0003 and 0.001 mg/kg, respectively. The average recoveries under different spiked levels were 85.53%-115.93%, and the relative standard deviations ( n =6) were 1.11%-8.48%. The established method was used to analyze 13 olive oil samples available in the market. Although no halogenated solvents were detected in these samples, a limited number of samples does not represent all olive oils. Hence, monitoring residual halogenated solvents in olive oil remains necessary for its safe consumption. The LOQs of the method for the six halogenated solvents were significantly lower than that of the COI/T.20/Doc. No. 8-1990 standard method (0.02 mg/kg). In addition, the developed method can be conducted under short operation times with high precision and degree of automation as well as good accuracy. Thus, the proposed method is suitable for the determination and analysis of the residues of the six halogenated solvents in large batches of olive oil samples.

An efficient and green method for synthesizing 3-methyl-4-(hetero) arylmethylene isoxazole-5(4H)-ones was developed using a recyclable and environmental-friendly catalyst, Na 2 S 2 O 3 , and 16 target compounds were successfully synthesized under the obtained optimal reaction condition. Using rifampicin as a positive control, the antibacterial activity of all synthesized compounds was tested by micro dilution method, among them, 3-methyl-4-[(2,4-dimethoxyphenyl) methylene]-isoxazole-5-one (4 m) presented wonderful antimicrobial activity, which may contribute to the development of anti-tuberculosis drugs., (© 2024 Wiley‐VHCA AG, Zurich, Switzerland.)

In contrast with the well-established C(sp 2 )-SCF 3 cross-coupling to forge the Ar-SCF 3 bond, the corresponding enantioselective coupling of readily available alkyl electrophiles to forge chiral C(sp 3 )-SCF 3 bond has remained largely unexplored. We herein disclose a copper-catalyzed enantioselective radical C(sp 3 )-SCF 3 coupling of a range of secondary/tertiary benzyl radicals with the easily available (Me 4 N)SCF 3 reagent. The key to the success lies in the utilization of chiral phosphino-oxazoline-derived anionic N,N,P-ligands through tuning electronic and steric effects for the simultaneous control of the reaction initiation and enantioselectivity. This strategy can successfully realize two types of asymmetric radical reactions, including enantioconvergent C(sp 3 )-SCF 3 cross-coupling of racemic benzyl halides and three-component 1,2-carbotrifluoromethylthiolation of arylated alkenes under mild reaction conditions. It therefore provides a highly flexible platform for the rapid assembly of an array of enantioenriched SCF 3 -containing molecules of interest in organic synthesis and medicinal chemistry., (© 2024 Wiley-VCH GmbH.)