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Theorthometalated [1-(dimethylamino)ethyl]naphthalene platinum(II) complexhas been used successfully to promote the asymmetric cycloadditionreaction between 3,4-dimethyl-1-phenylphosphole and sulfoxide in highselectivity. The exo-cycloadduct coordinated to theplatinum template as bidentate chelates via their phosphorus and sulfuratoms. The dichloro platinum complexes could be crystallized and werestable in the solid state as well as in solution. Optically pure P–Sbidentate ligands could be liberated from these dichloro complexesby treatment with aqueous potassium cyanide. The study also highlightsthe difference in reactivity and mode of substrate activation betweenan earlier study involving a Pd analogue of the template and the currentresults. [ABSTRACT FROM AUTHOR]

The organopalladium complex containing ortho-metallated (S)-[1-(dimethylamino)ethyl]naphthalene as a chiral auxiliary has been successfully employed to promote the asymmetric cycloaddition reaction between 3,4-dimethyl-1-phenylarsole and diphenylvinylarsine. In the intramolecular cycloaddition reaction, a pair of separable diastereomeric palladium complexes was obtained in the ratio of 6:1. The chiral naphthylamine auxiliary could be removed chemoselectively from the template by treatment with HCl and subsequently NaI to generate the neutral diiodo complex [(As-As)PdI2]. Treatment of the diiodo complex with KCN gave the enantiomerically pure As-As bidentate ligand in quantitative yield. In contrast to the reported similar P-P and As-P analogues, both arsenic donors in the diiodo complex could be readily eliminated to produce a structurally novel dimetallic complex. [ABSTRACT FROM AUTHOR]

The asymmetric cycloaddition reactions of 3,4-dimethyl-1-phenylarsole and (Z/E)-diphenyl-1-propenylphosphine/diphenyl-1-styrylphosphine promoted by a chiral organopalladium(ii) complex derived from (S)-[1-(dimethylamino)ethyl]naphthalene proceeded stereoselectively to generate different exo/endo-products. The reactions involving the (Z/E)-methyl substituted phosphines gave the individual optically pure exo- and endo-cycloadducts in very high stereoselectivity (33 : 1). However, when the methyl group was replaced by a Ph moiety both (Z/E)-phenyl substituted phosphines produced the same endo-cycloadduct in a stereoselectivity of 15 : 1. Every reaction produced five new chiral centers (four of them are sterically independent) in a single step and all three optically pure As–P heterobidentate ligands were obtained in high yields. The mechanism involved in the conversion of exo- to endo-product was investigated viadensity functional theory calculations. Computational results were consistent with the experimentally observed endo/exo-selectivity. [ABSTRACT FROM AUTHOR]

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 an air-sensitive solid by treatment of the complex with aqueous potassium cyanide. [ABSTRACT FROM AUTHOR]

The organopalladium complex containing ortho-metalated (S)-[1-(dimethylamino)ethyl]phenylene as the chiral auxiliary has been used as the chiral template to promote the asymmetric cycloaddition reaction between diphenylvinyiphos- phine and 3,4-dimethyl-1-phenylarsole. A diphenylphosphino-substituted asymmetrical heterobidentate arsanorbornene (As-P) ligand was obtained stereoselectively on the chiral palladium template in moderate yield. The chiral benzylamine auxiliary could be removed chemoselectively from the template by treatment with HCl to produce the neutral complex [(As-P)PdCl2]. In contrast to their reported P-P analogue, the arsenic donor in the dichloro complex could be eliminated stereospecifically under mild reaction conditions to generate the corresponding 1-(diphe- nylphosphino)-3,4-dimethyl-2,4-cyclohexadiene, which remained as a bidentate ligand at the PdCl2 unit via phosphorus and the η²-C4-C5 double bond. The arsenic-elimination process was found to be influenced by the halo ligand in [(As-P)PdX2]. A similar process was observed with the analogous dibromo complex, but the corresponding diiodo species did not show similar reactivity. All of the novel As-Pd complexes have been characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Compared with extensively applied lithium-ion batteries, potassium-ion batteries (PIBs) exhibit similar working principles, comparable energy densities but low costs and thus great potential in grid-scale energy storage applications. However, the K-storage performance of PIBs is significantly limited by the serious structure stress in electrode materials due to the large radius of K+ as well as poor electrolyte design principles to match the novel energy storage system. This review summarizes recent advances in material design of cathode and anode electrodes as well as electrolyte engineering for the novel electrochemical K-storage system. Especially the rational manipulation of the solid electrolyte interphase by electrolyte design to achieve satisfactory K-storage performance is emphasized. Furthermore, the guidelines and improved strategies are proposed for developing advanced PIBs for nextgeneration energy storage technologies. [ABSTRACT FROM AUTHOR]

Transformation of multifunctional materials with control over site-selectivity and chemical diversity remains challenging. Herein, we present a metal-free, one-pot strategy for the defluorophosphorylation of polyfluoroalkyl peroxides that enables expedient construction of structurally diverse phosphoryl-containing heterocyclic libraries. By judicious choice of reaction conditions, C3,4-diphosphoryl furans and C4-monophosphoryl furans can be easily accessed. In addition, synthetic derivatization of the obtained organophosphorus heteroarenes to value-added monodentate and bidentate phosphines has been demonstrated. Mechanistic studies revealed that regioselective defluorophosphorylation allows divergent product formation in two reaction modes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The well-defined heavy rare-earth ytterbium iodide complex 1 (L2YbI) has been successfully employed as an efficient catalyst for the hydroboration of a wide range of aldehydes and ketones with pinacolborane (HBpin) at room temperature. The protocol requires low catalyst loadings (0.1-0.5 mol %) and proceeds rapidly (>99% conversion in <10 min). Additionally, catalyst 1 shows a good functional group tolerance even toward the hydroxyl and amino moieties and displays chemoselective hydroboration of aldehydes over ketones under mild conditions. [ABSTRACT FROM AUTHOR]