Iron Corrole-Catalyzed Intramolecular Amination Reactions of Alkyl Azides. Spectroscopic Characterization and Reactivity of [Fe(Cor)(NAd)].

As nitrogen analogues of iron-oxo species, high-valent iron-imido species have attracted great interest in the past decades. Fe-alkylimido species are generally considered to be key reaction intermediates in Fe(III)-catalyzed C(sp)─H bond aminations of alkyl azides but remain underexplored. Here, it is reported that iron-corrole (Cor) complexes can catalyze a wide range of intramolecular C─H amination reactions of alkyl azides to afford a variety of 5-, 6- and 7-membered N-heterocycles, including alkaloids and natural product derivatives, with up to 3880 turnover numbers (TONs) and excellent diastereoselectivity (>99:1 d.

Effect of intercropping and biochar amendments on lead removal capacity by Corchorus olitorius and Zea mays.

Intercropping is a sustainable strategy recognized for boosting crop production and mitigating heavy metal toxicity in contaminated soils. This study investigates the effects of biochar amendments on Pb-contaminated soil, utilizing monocropping and intercropping techniques with C. olitorius and Z.

Integrative analysis of the transcriptome and metabolome reveals Bacillus atrophaeus WZYH01-mediated salt stress mechanism in maize (Zea mays L.).

Maize is an important food crop that is affected by salt stress during growth, which can hinder plant growth and result in a significant decrease in yield. The application of plant growth-promoting rhizobacteria can improve this situation to a certain extent. However, the gene network of rhizosphere-promoting bacteria regulating the response of maize to salt stress remains elusive.

Application of rhizobacteria to improve microbial community structure and maize (Zea mays L.) growth in saline soil.

The utilization of plant growth-promoting rhizobacteria (PGPR) has emerged as a prominent focus in contemporary research on soil microbiology, microecology, and plant stress tolerance. However, how PGPR influence the soil bacterial community and related ecological functions remains unclear. The aim of this study was to investigate the effects of three natural PGPR inoculations (YL07, Planococcus soli WZYH02; YL10, Bacillus atrophaeus WZYH01; YL0710, Planococcus soli WZYH02 and Bacillus atrophaeus WZYH01) on maize (Zea mays L.

Ruthenium(v) terminal arylimido corroles: isolation, spectroscopic characterization and reactivity.

Terminal Ru(v)-imido species are thought to be as reactive to group transfer reactions as their Ru(v)-oxo homologues, but are less studied. With the electron-rich corrole ligand, relatively stable and isolable Ru(v)-arylimido complexes [Ru(Bu-Cor)(NAr)] (H(Bu-Cor) = 5,15-diphenyl-10-(-butylphenyl)corrole, Ar = 2,4,6-MeCH (Mes), 2,6-(Pr)CH (Dipp), 2,4,6-(Pr)CH (Tipp), and 3,5-(CF)CH (BTF)) can be prepared from [Ru(Bu-Cor)] under strongly reducing conditions. This type of Ru(v)-monoarylimido corrole complex with = ½ was characterized by high-resolution ESI mass spectrometry, X-band EPR, resonance Raman spectroscopy, magnetic susceptibility, and elemental analysis, together with computational studies.

Effects of multiwalled carbon nanotube and application on crop root zone thermal characteristics of saline farmland.

Presently, the effects of crop roots on crop root zone thermal characteristics are poorly understood, and new fertilizers are rarely considered from the perspective of changing crop root zone thermal characteristics. This study explored the effect of applying two new fertilizers, multiwalled carbon nanotubes (MWCNTs) and (B. atrophaeus), on the crop root zone thermal characteristics of saline farmland soils through in situ measurements.

A Convergent, Modular Approach to Trifluoromethyl-Bearing 5-Membered Rings via Catalytic C(sp )-H Activation.

Trifluoromethyl-bearing 5-membered rings are prevalent in bioactive molecules, but modular approaches to these compounds by functionalization of robust C(sp )-H bonds in a direct and selective manner are extremely challenging. Herein we report the rhodium-catalyzed α-CF -α-alkyl carbene insertion into C(sp )-H bonds of a broad range of substrates to access 7 types of CF -bearing saturated 5-membered carbo- and heterocycles. The reaction is particularly effective for benzylic C-H insertion exerting good site-, diastereo- and enantiocontrol, and applicable to the synthesis of chiral CF analogues of bioactive molecules.

ChromosomeNet: A massive dataset enabling benchmarking and building basedlines of clinical chromosome classification.

Chromosome karyotyping analysis is a vital cytogenetics technique for diagnosing genetic and congenital malformations, analyzing gestational and implantation failures, etc. Since the chromosome classification as an essential stage in chromosome karyotype analysis is a highly time-consuming, tedious, and error-prone task, which requires a large amount of manual work of experienced cytogenetics experts. Many deep learning-based methods have been proposed to address the chromosome classification issues.

WZYH01 and WZYH02 Improve Salt Tolerance of Maize ( L.) in Saline Soil.

With the increasing shortage of land resources and people's attention to the ecological environment, the application of microbial fertilizer with natural soil microorganisms as the main component has attracted increasing attention in saline agriculture. In this study, two salt-tolerant strains, YL07 () and YL10 (), were isolated from maize ( L.) rhizosphere soil with a saturated conductivity (EC) of 6.

Self-Assembly of Molecular Trefoil Knots Featuring Pentadecanuclear Homoleptic Au -, Au /Ag -, or Au /Cu -Alkynyl Coordination.

Metal-free and metal-containing molecular trefoil knots are fascinating ensembles that are usually covalently assembled, the latter requiring the rational design of di- or multidentate/multipodal ligands as connectors. In this work, we describe the self-assembly of pentadecanuclear Au trefoil knots [Au (C≡CR) ] from monoalkynes HC≡CR (R=9,9-X -fluorenyl with X=nBu, n-hexyl) and [Au (THT)Cl]. Hetero-bimetallic counterparts [Au M (C≡CR) ] (M=Cu/Ag) were self-assembled by reactions of [Au (C≡CR) ] with [Cu(MeCN) ] /AgNO and HC≡CR.

Responses of the Soil Microbial Community to Salinity Stress in Maize Fields.

To investigate the diversity and structure of soil bacterial and fungal communities in saline soils, soil samples with three increasing salinity levels (S1, S2 and S3) were collected from a maize field in Yanqi, Xinjiang Province, China. The results showed that the K, Na, Ca and Mg values in the bulk soil were higher than those in the rhizosphere soil, with significant differences in S2 and S3 ( < 0.05).

Iron-Catalyzed Highly Enantioselective Addition of Silyl Enol Ethers to α,β-Unsaturated 2-Acyl Imidazoles.

A chiral Fe(N4) complex (N4 = (,)-,'-bis(2-isopropylquinolin-8-yl)-1,2-diphenylethane-1,2-diamine) was developed for the asymmetric conjugate addition of silyl enol ethers, including both acyclic ones and cyclohexenone-derived ones, to α,β-unsaturated 2-acyl imidazoles. This Fe complex is an effective chiral Lewis acid and was applied in the synthesis of an array of chiral 1,5-dicarbonyl synthons and cyclohexenone derivatives with high yields and enantioselectivities (up to 99% ee).

Ru -Acylimido Intermediate in [Ru (Por)Cl ]-Catalyzed C-N Bond Formation: Spectroscopic Characterization, Reactivity, and Catalytic Reactions.

Metal-catalyzed C-N bond formation reactions via acylnitrene transfer have recently attracted much attention, but direct detection of the proposed acylnitrenoid/acylimido M(NCOR) (R=aryl or alkyl) species in these reactions poses a formidable challenge. Herein, we report on Ru(NCOR) intermediates in C-N bond formation catalyzed by [Ru (Por)Cl ]/N COR, a catalytic method applicable to aziridine/oxazoline formation from alkenes, amination of substituted indoles, α-amino ketone formation from silyl enol ethers, amination of C(sp )-H bonds, and functionalization of natural products and carbohydrate derivatives (up to 99 % yield). Experimental studies, including HR-ESI-MS and EPR measurements, coupled with DFT calculations, lend evidence for the formulation of the Ru(NCOR) acylnitrenoids as a Ru -imido species.

[Source Apportionment of Ozone Pollution in Guangzhou: Case Study with the Application of Lagrangian Photochemical Trajectory Model].

A six-day ozone pollution episode in Guangzhou in early October 2018 was analyzed with the application of a Lagrangian photochemical trajectory model to trace the sources of ozone, quantify the contributions of different regions, and evaluate the effects of emission reduction measures targeted at different emission sectors and different precursors on ozone pollution. The results showed that during the ozone pollution episode, the maximum daily 8 h ozone exceeded 160 μg·m and the highest value reached 271 μg·m. The average concentrations of nitrogen oxides and volatile organic compounds (VOCs) were (77.

Iron-Catalyzed Highly Enantioselective cis-Dihydroxylation of Trisubstituted Alkenes with Aqueous H O.

Reliable methods for enantioselective cis-dihydroxylation of trisubstituted alkenes are scarce. The iron(II) complex cis-α-[Fe (2-Me -BQPN)(OTf) ], which bears a tetradentate N ligand (Me -BQPN=(R,R)-N,N'-dimethyl-N,N'-bis(2-methylquinolin-8-yl)-1,2-diphenylethane-1,2-diamine), was prepared and characterized. With this complex as the catalyst, a broad range of trisubstituted electron-deficient alkenes were efficiently oxidized to chiral cis-diols in yields of up to 98 % and up to 99.

Stable group 8 metal porphyrin mono- and bis(dialkylcarbene) complexes: synthesis, characterization, and catalytic activity.

Alkyl-substituted carbene (CHR or CR, R = alkyl) complexes have been extensively studied for alkylcarbene (CHR) ligands coordinated with high-valent early transition metal ions (a.k.a.

Development and environmental implication of pedotransfer functions of Cd desorption rate coefficients in historically polluted soils.

The desorption rate is an important factor determining cadmium (Cd) ecotoxicity and pollution remediation in soils. The pedotransfer functions (PTFs) of desorption rate coefficients of fresh Cd in soils have been developed in literature. We hypothesized that the aging of Cd pollution would alter Cd desorption process.

Solvent-Induced Cluster-to-Cluster Transformation of Homoleptic Gold(I) Thiolates between Catenane and Ring-in-Ring Structures.

Supramolecular ensembles adopting ring-in-ring structures are less developed compared with catenanes featuring interlocked rings. While catenanes with inter-ring closed-shell metallophilic interactions, such as d -d Au -Au interactions, have been well-documented, the ring-in-ring complexes featuring such metallophilic interactions remain underdeveloped. Herein is described an unprecedented ring-in-ring structure of a Au -thiolate Au cluster formed by recrystallization of a Au -thiolate Au [2]catenane from alkane solvents such as hexane, with use of a bulky dibutylfluorene-2-thiolate ligand.

Intramolecular Nitrene Insertion into Saturated C-H-Bond-Mediated C-N Bond Cleavage of a Coordinated NHC Ligand.

Ruthenium(II) complexes bearing a tridentate bis(N-heterocyclic carbene) ligand reacted with iminoiodanes (PhI=NR) resulting in the formation of isolable ruthenium(III)-amido intermediates, which underwent cleavage of a C-N bond of the tridentate ligand and formation of an N-substituted imine group. The Ru -amido intermediates have been characterized by H NMR, UV/Vis, ESI-MS, and X-ray crystallography. DFT calculations were performed to provide insight into the reaction mechanism.

Ruthenium(II) Porphyrin Quinoid Carbene Complexes: Synthesis, Crystal Structure, and Reactivity toward Carbene Transfer and Hydrogen Atom Transfer Reactions.

Reactivity study of novel metal carbene complexes can offer new opportunities in catalytic carbene transfer reactions as well as in other synthetic protocols. Metal complexes with quinoid carbene (QC) ligands are assumed to be key intermediates in a variety of metal-catalyzed QC transfer reactions using diazo quinones, which demands development of the chemistry of QC transfer of well characterized metal-QC complexes. Herein we report the isolation and QC transfer of ruthenium porphyrins [Ru(Por)(QC)] which contribute the first examples of (i) structurally characterized metal-QC complex (by X-ray crystallography) and (ii) isolated metal-QC complex that undergoes QC transfer reaction.

Stable iridium(iv) complexes supported by tetradentate salen ligands. Synthesis, structures and reactivity.

A series of trans-dichloroiridium(iv)-salen complexes were synthesized and structurally characterized by spectroscopic means and X-ray crystal structures. These Ir(iv) complexes are able to catalyze intramolecular C-H amination of aryl azides. The catalytic amination was drastically accelerated under microwave-assisted conditions, and possibly involves Ir-imido intermediates as supported by high-resolution ESI-MS analysis.

-Oxoruthenium complexes supported by chiral tetradentate amine (N) ligands for hydrocarbon oxidations.

We report the first examples of ruthenium complexes -[(N)RuCl] and -[(N)Ru(OH)] supported by chiral tetradentate amine ligands (N), together with a high-valent -dioxo complex -[(N)Ru(O)] supported by the chiral N ligand mcp (mcp = ,'-dimethyl-,'-bis(pyridin-2-ylmethyl)cyclohexane-1,2-diamine). The X-ray crystal structures of -[(mcp)RuCl](ClO) (), -[(Memcp)RuCl]ClO () and -[(pdp)RuCl](ClO) () (Memcp = ,'-dimethyl-,'-bis((6-methylpyridin-2-yl)methyl)cyclohexane-1,2-diamine, pdp = 1,1'-bis(pyridin-2-ylmethyl)-2,2'-bipyrrolidine)) show that the ligands coordinate to the ruthenium centre in a -α configuration. In aqueous solutions, proton-coupled electron-transfer redox couples were observed for -[(mcp)Ru(OCCF)]ClO () and -[(pdp)Ru(OSCF)]CFSO ().

cis-Dioxorhenium(V/VI) Complexes Supported by Neutral Tetradentate N Ligands. Synthesis, Characterization, and Spectroscopy.

A series of cis-dioxorhenium(V) complexes containing chiral tetradentate N ligands, including cis-[Re(O)(pyxn)] (1; pyxn = N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)cyclohexane-1,2-diamine), cis-[Re(O)(6-Mepyxn)] (cis-2), cis-[Re(O)(R,R-pdp)] (3; R,R-pdp = 1,1'-bis((R,R)-2-pyridinylmethyl)-2,2'-bipyrrolidine), cis-[Re(O)(R,R-6-Mepdp)] (4), and cis-[Re(O)(bqcn)] (5; bqcn = N,N'-dimethyl-N,N'-di(quinolin-8-yl)cyclohexane-1,2-diamine), were synthesized. Their structures were established by X-ray crystallography, showing Re-O distances in the range of 1.740(3)-1.

Assembly of strongly phosphorescent hetero-bimetallic and -trimetallic [2]catenane structures based on a coinage metal alkynyl system.

Homo-metallic metal alkynyl complexes exhibit interesting catenane structures, but their hetero-metallic catenane counterparts are under-developed. In this work, we report rare examples of bimetallic Au-Cu (DtbpC[triple bond, length as m-dash]C ligand; Dtbp = 3,5-di--butylphenyl), Au-Ag ( BuC[triple bond, length as m-dash]C ligand), and Au-Cu, Au-Ag (C6-FluoC[triple bond, length as m-dash]C ligand; C6-Fluo = 9,9-dihexyl-9-fluoren-2-yl) complexes as well as a trimetallic Au-Ag-Cu (C6-FluoC[triple bond, length as m-dash]C ligand) complex, which feature [2]catenane structures. The formation of the [2]catenane structure is significantly affected by the coinage metal ion(s) and change of the structure of the alkynyl ligand.