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The emerging potassium-ion batteries (PIBs) have been placing stratospheric expectations for realizing grid-scale electrochemical storage of renewable energy. However, the unsatisfactory K-storage of PIB anode materials, especially promising carbonaceous materials, significantly limited the development of PIBs. Here, a molecular design strategy was proposed to realize controllable structure transformation of soft carbon (SC) materials for enhanced K-storage performance. The optimized SC-PCN material delivered a high reversible K-storage capacity of 838 mAh/g at 50 mA/g, outstanding rate capability (213 mAh/g at 1000 mA/g), and excellent long-term cycling performance (301 mAh/g maintained after 300 cycles at 500 mA/g), superior to most previously reported carbon-based PIB anodes materials. Reaction kinetic analysis revealed that the proposed molecular design strategy can achieve the transformation from a surface capacitive-dominated mechanism to a capacitive-diffusion hybrid mechanism for SC-PCN, benefiting from its unique microstructures with highly defective surface generated via the synergistic effect from template removal, N doping, and surface reconstruction. The optimal hybrid K-storage mechanism should be responsible for the excellent K-storage properties of the prepared SC-PCN.

The direct cross-couplings of diaryl sulfoxides with aryl bromides via C-S bond cleavage could be readily accomplished using nickel(II) as the catalyst, 1,2-bis(diphenylphosphino)ethane (dppe) as the ligand, and magnesium turnings as the reducing metal in THF, leading to the corresponding biaryls in moderate to good yields. The reaction exhibited a broad substrate scope and could be applied to a gram-scale synthesis. The "one-pot" reaction, which avoids the utility of presynthesized and moisture-labile organometallic compounds, is operationally simple and step-economic.

The efficient palladium-catalyzed synthesis of esters from readily available arenes has been developed. These C-H bond esterifications were achieved relying on the regioselective thianthrenation to generate the aryl-TT salts, which were treated as reactive electrophilic substrates to couple with phenol formate and

Diverse 2,3-substituted indanones are accessed in an efficient and robust protocol by a rhodium-catalyzed tandem carborhodium/cyclization and intramolecular proton shift pathway. The reaction is compatible with a broad range of functional internal acetylenes, especially for natural and functionalized alkynes derivatives, affording the desired indanones in good to excellent yields. Remarkably, this reaction features very mild and sustainable conditions using water as the sole solvent and without exogenous ligands. Control studies support that indanone is formed through the intramolecular proton transfer process from the key intermediate indenol.

We report a general, scalable, and convenient photochemical process for diversities of distal oxygenated nitriles from corresponding less-strained ketoxime esters allowing one-step introductions of ether and cyano groups, which avoids the utilization of toxic cyanide reagents. A wide range of ketoxime esters involving five-membered to eight-membered cycloketoxime esters and linear ketoxime esters participate smoothly under operately simple and mild conditions, affording structurally variable ring-opening products.

The simple, commercially available ZnBr2 has been successfully employed as a highly efficient and chemoselective catalyst for the dehydrogenative borylation of terminal alkynes with HBpin under mild conditions. It shows a good tolerance toward various functional groups such as aryl, alkyl, heteroaryl, etc. The plausible reaction mechanism has been investigated based on the corresponding stoichiometric experiments and DFT calculations.

A nickel-catalyzed direct reductive cross-coupling of disubstituted cycloalkyl iodides with aryl iodides was developed. The one-pot reaction, which is simple to operate, was capable of proceeding efficiently in a stereocontrolled manner to afford a variety of cross-coupled products with high diastereoselectivity and wide functional group tolerance.

The orthometalated [1-(dimethylamino)ethyl]naphthalene platinum(II) complex has been used successfully to promote the asymmetric cycloaddition reaction between 3,4-dimethyl-1-phenylphosphole and sulfoxide in high selectivity. The exo-cycloadduct coordinated to the platinum template as bidentate chelates via their phosphorus and sulfur atoms. The dichloro platinum complexes could be crystallized and were stable in the solid state as well as in solution. Optically pure P–S bidentate ligands could be liberated from these dichloro complexes by treatment with aqueous potassium cyanide. The study also highlights the difference in reactivity and mode of substrate activation between an earlier study involving a Pd analogue of the template and the current results.

The organopalladium complex containing ortho-metalated (S)-[1-(dimethylamino)ethyl]naphthalene as the chiral auxiliary has been used successfully to promote the asymmetric cycloaddition reaction between 3,4-dimethyl-1-phenylarsole and diphenylvinylphosphine oxide in high stereoselectivity (only one isomer). However, the neutral dichloro palladium complex obtained upon removal of the auxiliary is very unstable and instantly decomposed to produce the arsenic elimination reaction product (3,4-dimethyl-2,4-cyclohexadienyl)diphenylphosphine oxide. However when the same reaction was promoted by the analogous platinum complex, only one stereoisomer was again obtained, but the resulting dichloro platinum complex is very stable in the solid state as well as in solution and coordinates to the platinum center as a As−O bidentate ligand, as confirmed by 1H NMR and single-crystal X-ray analysis. The enantiomerically pure As P═O hetero-bidentate ligand could be readily liberated from the dichloro platinum complex as a...

Ester- and keto-functionalized allylic monophosphine palladium complexes containing ortho-metalated (R)-(1-(dimethylamino)ethyl)naphthalene as the chiral auxiliary were synthesized via a versatile one-pot process. Subsequent asymmetric hydrophosphination of the coordinated allylic substrates promoted by the chiral auxiliary gave the corresponding functionalized chiral 1,2-bis(diphenylphosphino)ethane ligands in high yields under mild conditions. The coordination properties and absolute configurations of the resultant diphosphine ligands were established by single-crystal X-ray crystallography. The coordinated 1,2-diphosphine ligands could be subsequently liberated stereospecifically to yield enantiomerically pure functionalized diphosphines in high yields.

A series of amine bis(phenolato)lanthanide methyl and amido complexes were synthesized by general salt metathesis reaction in this paper. The reaction of anhydrous lanthanide trichlorides with 1 equiv of sodium amine bis(phenolate) LNa2 [L = Me2NCH2CH2N{CH2-(2-O-C6H2-But2-3,5)}2] in THF at room temperature gave the amine bis(phenolate) lanthanide chlorides LLnCl(THF) (Ln = Yb (1), Ln = Er (2)). Complexes 1 and 2 can be used as starting materials to prepare amine bis(phenolate) lanthanide derivatives. Complexes 1 and 2 reacted with lithium methyl and lithium amide, respectively, to give the corresponding lanthanide methyl and amido products LLnMe(THF) (Ln = Yb (3), Ln = Er (4)) and LLnNPh2(THF) (Ln = Yb (5), Ln = Er (6)). These complexes were well characterized by elemental analyses and IR spectra. The definitive molecular structures of complexes 1, 2, 3, 5, and 6 were provided by single-crystal X-ray analyses. Reactivity studies of complexes 3, 5, and 6 have shown them to be efficient initiators for the r...