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An N-heterocyclic carbene (NHC)-catalyzed strategy has been developed to address the issue of using toxic transitional metals in the field of C-C bond activation. The novel reaction mode enables an efficient docking between the cyanoalkyl from the cycloketone oxime derivative and the acyl group from the aldehyde, affording ketonitrile in moderate to good yields, which is one kind of useful building block for synthesizing nitrogen-containing pharmacophores.

A new general de novo synthesis of pharmaceutically important α-aryl β-perfluoroalkyl ketones has been disclosed. Compared with trifluoromethylation-initiated radical 1,2-aryl migration of α,α-diaryl allylic alcohols, this protocol employs a new strategy of biomimetic carbene catalysis to assemble alkene, aldehyde and perfluoroalkyl reagents, providing access to products with excellent flexibility of the aryl unit and perfluoroalkyl group. This method also demonstrates excellent functional group compatibility, including some Grignard reagent sensitive groups.

A nickel-catalyzed 1,2-aminoarylation of oxime-ester-tethered alkenes with boronic acids was developed. A variety of pyrroline derivatives were synthesized in good yields via the successive formation of C(sp3)–N and C(sp3)–C(sp2) bonds. For cyclobutanone-derived oxime esters, the reaction provided aliphatic nitriles incorporating an aromatic group in the γ-position. A mechanism involving iminyl radical and carbon-centered radical intermediates was proposed.

Aiming at the problem that the amount of calculation of correlation energy analysis is too large in the process of attacking multiple S-box corresponding keys, this paper proposes a multiple S-box correlation energy analysis model based on particle swarm optimization. The particle swarm optimization algorithm has the characteristics of simple structure, fast search speed and memory, therefore, our model simultaneously attacks multiple S-boxes, which can reduce the amount of calculation, thereby achieving the goal of recovering the key efficiently and correctly. Finally, experimental analysis and verification results of the DES algorithm indicate that our new energy analysis model has about 55% improvement in efficiency and 30% improvement in accuracy over traditional energy analysis models.

A new method for the direct functionalization of diamondoids has been developed using photoredox and H-atom transfer catalysis. This C–H alkylation reaction has excellent chemoselectivity for the strong 3º C–H bonds of adamantanes in polyfunctional molecules. In substrate competition reactions, a reversal in selectivity is observed for the new H-atom transfer catalyst reported here when compared to six known photochemical systems. Derivatization of a broad scope of diamondoids and adamantane-containing drugs highlights the versatility and functional group tolerance of this C–H functionalization strategy.

A redox-economical strategy for the synthesis of trifluoromethylated enamides using copper catalysis is reported. The reaction employs the inexpensive Langlois reagent (CF3SO2Na) and takes place without the need of an external oxidant. The trifluoromethylated enamide products can easily be converted into the corresponding ketone, saturated amide or oxazole.

An iron-catalyzed coupling reaction of O-acyloximes and O-benzoyl amidoximes with silyl enol ethers is reported. The protocol provides access to functionalized pyrroles, 1,6-ketonitriles, pyrrolines and imidazolines via carbon-centered radicals generated from an initially formed iminyl radical. The intramolecular cyclization and ring-opening processes of the iminyl radical take place preferentially over reactions that proceed through a 1,3-hydrogen transfer, providing insights into iron-catalyzed reactions with oxime derivatives. The cheap and environmentally friendly iron catalyst, the broad substrate scope and the functional group compatibility make this protocol useful for synthesis of valuable nitrogen-containing products.

Biological treatment played an important role in the treatment of landfill leachate. In the current study, acid mine drainage (AMD) was used as a source of sulfate to strengthen the anaerobic treatment of landfill leachate. Effects of chemical oxygen demand (COD) and SO42- mass concentration ratio on the decomposition of organic matter, methane production and sulfate reduction were investigated and the microbial community was analyzed using the high throughout methods. Results showed that high removal efficiency of COD, methane production and heavy metal removal was achieved when the initial COD/SO42- ratio (based on mass) was set at 3.0. The relative abundance of anaerobic hydrogen-producing bacteria (Candidatus Cloacamonas) in the experimental group with the addition of AMD was significantly increased compared to the control. Abundance of hydrogenotrophic methanogens of Methanosarcina and Methanomassiliicoccus was increased. Results confirmed that AMD could be used as sulfate resource to strengthen the biological treatment of landfill leachate.

A novel intramolecular oxycyanation of methylenecyclopropanes is reported that proceeds through oxidative cleavage of the N-CN bond and subsequent palladium transfer from N to O of the amide group. A range of substituted benzo[d][1,3]oxazines with a cyano group are readily furnished by this newly developed oxycyanation reaction. Tris(4-trifluoromethylphenyl)phosphine as a ligand has been found to be crucial to effectively promote the transformation with high chemo- and regioselectivity. Moreover, the reaction outcome can be significantly affected by the electronic effect of the acyl group attached to the nitrogen atom of methylenecyclopropanes. When R(3) is a chloromethyl group, the pyrrolo[2,3-b]quinoline derivative is obtained by thermal-induced [3+2] cycloaddition of methylenecyclopropane to the methanediimine intermediate.