37 research outputs found

    Palladium-Catalyzed Direct Intermolecular α‑Arylation of Amides with Aryl Chlorides

    No full text
    An efficient catalytic system for the direct intermolecular α-arylation of acetamide derivatives with aryl chlorides is presented. Chemoselectivities up to 10:1 in the mono- and diarylation of acetamides were achieved by careful selection of bases, solvents, and stoichiometry. Bis-arylated amides were prepared in up to 95% yield

    Palladium-Catalyzed Direct α‑Arylation of Methyl Sulfones with Aryl Bromides

    No full text
    A direct and efficient approach for palladium-catalyzed arylation of aryl and alkyl methyl sulfones with aryl bromides has been developed. The catalytic system affords arylated sulfones in good to excellent yields (73–90%)

    Engineering the Work Function of Buckled Boron α‑Sheet by Lithium Adsorption: A First-Principles Investigation

    No full text
    First-principles density functional theory calculations were performed to study the effect of Li adsorption on the structural and electronic properties, particularly the work function, of boron α-sheet. The calculated binding energies indicated that boron α-sheet could be well stabilized by the adsorption of Li atoms. Furthermore, the work functions of Li-adsorbed boron α-sheets were observed to decrease drastically with increasing Li coverage. The work functions are lower than that of Mg and even, for some of them, lower than that of Ca, indicating a considerable potential application of Li-adsorbed boron α-sheets as field-emission and electrode materials. Based on the calculated geometric and electronic structures, we discuss in details some possible aspects affecting the work function. The Li coverage dependence of the work functions of Li-adsorbed boron α-sheets was further confirmed by electrostatic potential analyses. The relationship between the work function variation and the Fermi and vacuum energy level shifts was also discussed, and we observed that the variation of the work function is primarily associated with the shift of the Fermi energy level. It is the surface dipole formed by the interaction between adatoms and substrate that should be responsible for the observed variation of the work function, whereas the increasing negative charge and rumpling for boron α-sheet only play minor roles. Additionally, the effect of Li adatoms on the work function of boron α-sheet was confirmed to be much stronger than that of graphene or a graphene double layer
    corecore