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Metal‐free, visible light‐induced difunctionalizations of α‐CF3 styrenes with aryl diazonium salts and various hetero nucleophiles (ROH, H2O, N3− and F−) are described. This concise protocol provided easy access to the α‐CF3 tertiary alkyl ethers, alcohol and fluorides with good yields and excellent functional group tolerance. In addition, the four‐component "SO2" insertion reaction also worked efficiently to produce the α‐CF3, β‐sulfonyl ethers in moderate to good yields. A radical‐polar crossover coupling pathway was proposed for the C−O bond formation. [ABSTRACT FROM AUTHOR]

Both organic radicals and organoboron reagents have been broadly investigated, but the combination of them via direct C−H borylation as organic radical building blocks has never been achieved. Herein, a series of organoradical boron reagents, such as TTM‐Bpin and TTM‐BOH, were synthesized through the key step of C−H borylation of substrate TTM‐H ((2,6‐dichlorophenyl) bis(2,4,6‐trichlorophenyl)methyl) radical for the first time. They are air stable enough to be stored in the solid state for several months under dark conditions, and fully investigated through single crystal analysis, EPR and DFT calculations. Furthermore, they can smoothly work in the standard Suzuki–Miyaura coupling (SMC) reaction with retention of the carbon radical center. Meanwhile, these radical species bearing different boron units display fluorescent character and are potentially applied for the collective synthesis of luminescent organic radicals, as well as other functionalized open‐shell materials. [ABSTRACT FROM AUTHOR]

The TTG (tonalite‐trondhjemite‐granodiorite) rock suites are major building blocks of the Archean continental crust and their timing of formation and petrogenetic evolution are important keys to understanding the growth of continents in the Early Earth. Here we investigate trondhjemites from the Qiangxi Complex in the North China Craton and present petrological, geochemical and zircon U–Pb, REE and Lu–Hf data to understand the timing of their formation and petrogenetic history. The trondhjemites in our study belong to typical Archean Na‐rich TTG rocks and their geochemical features are similar to high‐Al TTG rocks. The geochemical characteristics of these rocks and the associated amphibolite indicate derivation from a subduction‐related hydrous basalt. The magmatic zircon grains from the trondhjemite samples show a peak 207Pb/206Pb age around 2,515 Ma. Magmatic zircon in the associated amphibolite also shows a similar age representing the timing of the protolith formation. Both the trondhjemites and amphibolite also contain metamorphic zircon grains which constrain the timing of metamorphism as 2,451–2,490 Ma, suggesting high‐grade metamorphism closely following the magmatism, associated with the assembly of the microblocks in the NCC. The geochemical characteristics and zircon age data presented in this study, in conjunction with those in previous studies from the Qiangxi Complex, suggest subduction‐related arc building occurred dominantly during 2.6–2.5 Ga. The Lu‐Hf isotope data from zircon grains in the trondhjemite and amphibolite samples of this study show dominantly positive εHf(t) values, indicating that the protolith magma was derived from juvenile components or depleted mantle. Our new results in conjunction with the data reported in earlier studies indicate a major crust‐building event through multiple magmatism during Neoarchean. The depleted mantle ages (TDM) of zircon in our samples range from 2,857 Ma to 2,605 Ma indicating that active subduction might have initiated in the late Mesoarchean, with the peak of magmatism during 2.6–2.5 Ga, followed by metamorphism at ca. 2.45–2.49 Ga. [ABSTRACT FROM AUTHOR]

An efficient iron‐catalyzed allylation of cycloalkyl hydroperoxides with allylic sulfones via C−C bond cleavage is presented. This protocol provides an efficient approach to a wide range of distally allylated ketones with good functional group tolerance and high regioselectivity under redox‐neutral conditions. Preliminary mechanistic study implies a radical process might be involved in this reaction. [ABSTRACT FROM AUTHOR]

Summary: The relative abundance of Acidobacteriia correlated positively with the concentrations of arsenic (As), mercury (Hg), chromium (Cr), copper (Cu) and other metals, suggesting their adaptation of the metal‐rich environments. Metagenomic binning reconstructed 29 high‐quality metagenome‐assembled genomes (MAGs) associated with Acidobacteriia, providing an opportunity to study their metabolic potentials. These MAGs contained genes to transform As, Hg and Cr through oxidation, reduction, efflux and demethylation, suggesting the potential of Acidobacteriia to transform such metal(loid)s. Additionally, genes associated with alleviation of acidic and metal stress were also detected in these MAGs. Acidobacteriia may have the capabilities to resist or transform metal(loid)s in acidic metal‐contaminated sites. Moreover, these genes encoding metal transformation could be also identified in the Acidobacteriia‐associated MAGs from five additional metal‐contaminated sites across Southwest China, as well as Acidobacteriia‐associated reference genomes from the NCBI database, suggesting that the capability of metal transformation may be widespread among Acidobacteriia members. This discovery provides an understanding of metabolic potentials of the Acidobacteriia in acidic metal‐rich sites. [ABSTRACT FROM AUTHOR]

The majority of patients with microsatellite stable (MSS) colorectal cancer (CRC) do not benefit from the immunotherapies directed at rescuing T‐cell functions. Therefore, complete understanding of T‐cell phenotypes and functional status in the CRC microenvironment is desirable. Here, we applied single‐cell mass cytometry to mold the T‐cell phenotype in 18 patients with MSS CRC for better understanding of CRC as a systemic disease and to search for tumor‐driven T‐cell profile changes. We show interpatient and intrapatient phenotypic diversity of T‐cell subsets. We revealed increased immunosuppressive/exhausted T‐cell phenotypes at tumor lesions. CD8+ CD28− immunosenescent T cells with impaired proliferation capacity dominate the T‐cell compartment. As per the transcriptome and quantitative real time‐PCR analysis, the accumulation of immunosuppressive cells is driven by the tumor microenvironment. T‐cell profiles are similar between patients at early and late stages, indicating that the immunosuppressive microenvironment is formulated early during CRC development. Mapping of T‐cell infiltration and understanding of the mechanisms underlying their regulation may provide valuable information to boost the immune response in patients with MSS CRC. What's new? Most patients with microsatellite stable (MSS) colorectal cancer (CRC) do not benefit from current immunotherapies. T cell phenotypes and functional status in the CRC microenvironment remain poorly understood, however. Here, the authors mapped T cell phenotypes in tumor lesions, non‐tumorous adjacent tissues, and matched blood samples using single‐cell mass cytometry. They revealed interpatient T cell heterogeneity and increased immunosuppressive T cell phenotypes at tumor lesions. Moreover, the tumor microenvironment hosted chemokines/cytokines that likely recruit immunosuppressive/exhausted T cell subsets. Mapping T cell infiltration and better understanding T cell regulation mechanisms may help boost the immune response in patients with MSS CRC. [ABSTRACT FROM AUTHOR]

Crystal density is a basic and important parameter for predicting the detonation performance of explosives. In this study, the densities of 35 cyclic organic fluorides, a kind of compounds with wide applications, are investigated using three density functionals (B3LYP, B3PW91, M06‐2X) and six basis sets (such as 6–31G*, 6–31+G* and 6–31G**) via two approaches (A and B). Compared with the experimental results, the calculated densities by various methods are all overestimated. However, the densities obtained by M06‐2X/6‐31G* via the approach A show a good linear correlation with the experimental values, therefore, they can be systematically corrected using the correlation equation to reproduce the experimental crystal densities satisfactorily. In addition, the effects of various groups (−NO2, −CH2−, −CF(NO2)2, −CNF2(NO2)2, −CF3, −SF5, and −NF2) on the densities of organic fluorides, which is helpful for the design of new fluorine‐containing molecules in terms of requirement, have also been discussed. [ABSTRACT FROM AUTHOR]

Nitrogen‐rich compounds involving the cyclo‐pentazole anion (cyclo‐N5−) have attracted extensive attention due to higher energy release and environmental friendliness than traditional high energy density materials (HEDMs). However, the synthesis of stable HEDMs with cyclo‐N5− is still a challenge. In this study, the effect of nine solvents on the geometrical and electronic structures and solvation energies of Zn(N5)2, one of the recently synthesized nitrogen‐rich compounds, was studied using the density functional theory and the polarized continuum model. The results indicated an increase in the stability of Zn(N5)2 in the solution phase compared to the vacuum phase, and the stability of Zn(N5)2 increases with increasing dielectric constants. The energy gap of frontier molecular orbitals and the absolute value of total energy in water are the largest, revealing that Zn(N5)2 is more stable in water than in other solvents. To understand the stabilization mechanism of Zn(N5)2 by water, further studies were performed with the natural bond orbital (NBO) analysis and the quantum theory of atoms in molecules (QTAIM) analysis using the explicit solvent model. The charge transfer and the hydrogen bonds are observed between Zn(N5)2 and water, which are beneficial to improvement of the stability of Zn(N5)2. This may indicate the solvents that have strong interactions with the cyclo‐N5− candidate may improve the possibility of success of synthesis. [ABSTRACT FROM AUTHOR]

Ocean island basalts (OIBs) and associated sedimentary units form part of the ocean plate stratigraphy accreted onto island arcs or continental arcs and provide important insights into convergent margin processes. Here, we investigate some of the typical localities of Sanpozan, Shirakidani, and Kamiananai within the Chichibu composite belt in Kochi, SW Japan, where the accretionary complexes incorporate OIBs and sedimentary rocks that preserve the travelogue of an oceanic plate from a mid‐oceanic ridge (MOR) to subduction zone. We present petrology and geochemistry, as well as zircon U–Pb geochronology and REE data of the accreted OIB and sedimentary formations from Sanpozan, Shirakidani, and Kamiananai. The OIBs are enriched in LILE and LREE and depleted in HREE. The chondrite‐normalised REE patterns of zircon grains from OIBs and sedimentary rocks display LREE depletion and HREE enrichment, sharply positive Ce and Sm anomalies and negative Pr and Eu. LA‐ICP‐MS U–Pb geochronology of zircon grains from the OIBs shows three major populations with 206Pb/238U mean ages of 164–456, 724–955, and 1,638–2,202 Ma. The diverse ages suggest heterogeneous recycled source components in the plume‐related upwellings that generated the OIBs, as well as different times of formation and accretion of the Palaeozoic and Mesozoic oceanic islands. The dominant population of zircon grains from the sedimentary units shows 206Pb/238U mean ages of 147 and 288 Ma and indicate a major change in the provenance regime with subduction and the disappearance of older arcs attesting to the destruction of continental crust in convergent margins. [ABSTRACT FROM AUTHOR]

A method for the construction of boron‐substituted quaternary carbons or diarylquaternary carbons by arylboration of highly substituted alkenylarenes is presented. A wide range of alkenes and arylbromides can participate in this reaction thus allowing for a diverse assortment of products to be prepared. In addition, a solvent dependent regiodivergent arylboration of 1,2‐disubstituted alkenylarenes is presented, thus greatly increasing the scope of products that can be accessed. [ABSTRACT FROM AUTHOR]

Abstract: An iron‐catalyzed radical allylation of cyclobutanone oxime esters with allylic sulfones via C−C bond cleavage is reported. This protocol provides a straight‐forward approach to cyanoalkylated alkenes with good functional group tolerance and high regioselectivity. Furthermore, this reaction can be further expanded to ring‐opening of less‐strained cyclopentanone oxime esters, leading to desired cyanoalkylated alkenes in good yields. [ABSTRACT FROM AUTHOR]

A practical and efficient approach for the synthesis of various sulfonyl-substituted vinyl arenes is reported. In the process, hydrazones provide coupling partners for the Pd-catalyzed cross-coupling with aryl halides and sulfinate salts as nucleophiles, which realizes minimal waste and excellent atom economy. [ABSTRACT FROM AUTHOR]

In the last few years, the development of versatile methodologies to incorporate trifluoromethyl groups into organic molecules has attracted significant attention in synthetic chemistry. This review gives an overview over the development on the trifluoromethylation of alkynes, which have not been solely discussed before. Formation of diverse C(sp, sp2, sp3)CF3 bonds are all covered in this review. [ABSTRACT FROM AUTHOR]

A copper-catalyzed difunctionalizing trifluoromethylation of activated alkynes with the cheap reagent sodium trifluoromethanesulfinate (NaSO2CF3 or Langlois' reagent) has been developed incorporating a tandem cyclization/dearomatization process. This strategy affords a straightforward route to synthesis of 3-(trifluoromethyl)-spiro[4.5]trienones, and presents an example of difunctionalization of alkynes for simultaneous formation of two carbon-carbon single bonds and one carbon-oxygen double bond. [ABSTRACT FROM AUTHOR]

Keratin biosorbents were prepared by reprocessing the deposits produced from chicken feathers after soluble keratin extraction. Biosorption of Cr(VI) ions onto the obtained biosorbents from aqueous solution was studied. Experimental factors affecting biosorption process such as pH and initial concentration of Cr(VI) ions were investigated. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models were used to describe the biosorption process for Cr(VI) ions. The results showed that Langmuir model better fit the experimental data than the Freundlich and D-R models, and the maximum monolayer biosorption capacity for Cr(VI) ions was found to be 21.35 mg/g at pH 6, 200 mg/L initial concentration of Cr(VI) ions and 30°C. The free energy was calculated as 11.35 kJ/mol from the D-R model, indicating that the biosorption of Cr(VI) occurred chemically. This result was also confirmed by scanning electron microscopy and Fourier transform infrared regarding the changes in morphology and surface structure of the biosorbents before and after Cr(VI) biosorption. Overall, the deposits generated from chicken feathers after soluble keratin extraction, which currently treated as wastes, should be regarded as a favorable alternative for the removal of Cr(VI) ions from aqueous solution. [ABSTRACT FROM AUTHOR]

A novel copper-catalyzed one-pot functionalization of homopropargylic alcohols that involves trifluoromethylation, aryl migration, and formation of a carbonyl moiety has been developed. This reaction constitutes the first direct conversion of homopropargylic alcohols into CF3-containing 3-butenal or 3-buten-1-one derivatives in a regioselective manner. Mechanistic studies indicate that the 1,4-aryl migration proceeds through a radical pathway. [ABSTRACT FROM AUTHOR]

Regioselective trifluoromethylation–cyclization: A method for copper‐catalyzed trifluoromethylation–cyclization of simple enynes using the CC triple bond as a nucleophile is reported for the first time (see scheme). The reaction proceeds efficiently in a highly regioselective manner to give various 5‐ or 6‐exo‐dig carbocycles and heterocycles in moderate to high yields. [ABSTRACT FROM AUTHOR]

Acrylic acid graft onto corn starch with excellent water holding capacity were successfully synthesized and employed for copper ions removal in aqueous solution. N, N′-methylenebisacrylamide and potassium persulfate effectively worked as cross-linking agent and the reaction initiator for copolymerization reaction, respectively. The data of FTIR confirmed that acrylic acid has been grafted onto starch. The effect of time on the water holding performance was investigated, and its maximum value was 96.6 g/g. The copolymers were dispersed in aqueous solution of Cu2+ ions and form polymer-copper ions complex. The copper ions removal capacity of grafted starch was investigated by UV-visible spectrophotometry as a function of pH, water holding capacity, the content of NaCl, and the initial concentration of copper ions. In the presence of NaCl, the highest copper ions removal capacity was 2.56 mmol copper ions per gram of grafted starch, and 85.3% of copper ions have been removed. The isothermal study indicated that the adsorption data could be well modeled by Langmuir isotherms. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of the MeOH extract of Valeriana fauriei Briq. roots resulted in the isolation of two new sesquiterpenes, isovalerianin A (=(1 β,4 Z,6 β,8 α)-8-(acetyloxy)-1,10-dihydroxy-6,11-cyclogermacr-4-en-15-al= rel-(1 R,2 Z,6 S,7 R,9 R,10 S)-9-(acetyloxy)-6,7-dihydroxy-7,11,11-trimethylbicyclo[8.1.0]undec-2-ene-3-carboxaldehyde; 1) and valerianin C (=(2 α,3 α,6 α,8 α)-3-(acetyloxy)-2,4,8-trihydroxyguai-1(10)-ene-12,6-lactone= rel-(3 R,3a S,4 R,7 S,8 S,9 R,9a R,9b R)-8-(acetyloxy)-3a,4,5,7,8,9,9a,9b- octahydro-4,7,9-trihydroxy-3,6,9-trimethylazuleno[4,5- b]furan-2(3 H)-one; 2), together with six known compounds, i.e., camphor, methyl 4-hydroxybenzoate, 2-methoxybenzoic acid, benzoic acid, quercetin, and kaempferol. The structures of the compounds were established by detailed spectral analysis and comparison with previously reported data. [ABSTRACT FROM AUTHOR]

A platinum-catalyzed cascade heterocyclization and formal [3+2] cycloaddition reaction of 2-(1-alkynyl)-3-aryl-2-propenals and arylethenes has been developed. This cyclization reaction shows excellent regioselectivity to obtain highly substituted 4 H-cyclopenta[ b]furans in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

Two new abietane-type diterpenoids, named triptobenzene R ( 1) and triptobenzene S ( 2), together with three known abietane-type diterpenoids, triptophenolide ( 3), triptonodiol ( 4), and triptonoterpene methyl ether ( 5), were isolated from the roots of Tripterygium wilfordii Hook. f. Their structures and relative configurations were established by detailed spectral studies, including 1D- and 2D-NMR (HSQC, HMBC, and NOESY), and HR-ESI-TOF-MS, and by comparison with published data. Their absolute configurations were assigned by the CD technique, applied for the first time to abietane diterpenes from Tripterygium wilfordii. Compound 2 is the first abietane-type norditerpenoid isolated from the genus Tripterygium. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the main components and mass percentage of resol through liquid chromatography-mass spectrograph (LC-MS). Formation of resol can be examined by analyzing the sum of percentage of formaldehyde, phenol, and first formed addition products. Synthesis of resol with hydroxymethyl yielded condensation compounds of low molecular weight with kinetics of the synthesis derived from three producing and condensation stages of the hydroxymethylphenol groups.

Chemical equations are presented for the article "AgSCF3-Mediated Oxidative Trifluoromethythiolation of Alkynes with Dearomatization to Synthesize SCF3-Substituted Spiro[4,5]trienones" by D.-P. Jin and colleagues, published in the periodical "Organic Letters."

The presented approach can be scaled up to gram quantities in satisfactory yields. [ABSTRACT FROM AUTHOR]

The title compounds are obtained from unprotected homopropargylic alcohols with high regioselectivity. [ABSTRACT FROM AUTHOR]

Review: 49 refs. [ABSTRACT FROM AUTHOR]

Abstract: The scalable iron‐catalyzed aerobic oxidative reaction is influenced by the steric hindrance of the substrates′ aryl substituents. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Copper(II)-Catalyzed Direct Thiolation of C-H Bonds in Aromatic Amides with Aryl and Aliphatic Thiols" by X.-B. Yan and others, published in the periodical "Tetrahedron" in 2014.

The article presents chemical equations related to the article "Copper-Catalyzed Trifluoromethylation-Cyclization of Enynes: Highly Regioselective Construction of Trifluoromethylated Carbocycles and Heterocycles" by P. Gao and others, published in the "Chemistry: A European Journal" in 2013.

Cu2Cl(OH)3 microspheres are obtained by freeze drying of a frozen solution of CuCl2 in EtOH/H2O (3.5:1) with a 10 fold amount of propylene oxide (12 h of stirring under ambient conditions, cooling to -196 °C). [ABSTRACT FROM AUTHOR]

The article presents a diagram of the regioselective synthesis of highly substituted 4H-cyclopenta[b]furans using platinum (IV) catalysts through cascade heterocyclization of 2-(1-alkynyl)-3-aryl-2-propenals with arylethenes.