RESUMO
MOF (metal organic framework) materials have been used as functional materials in a number of fields due to their diverse spatial tunability, which produces rich porous structures with stable and continuous pores and a high specific surface area. A triboelectric nanogenerator can convert trace mechanical energy into electrical energy, and the application of MOF materials to triboelectric nanogenerators has been intensively studied. In this work, we report on two MOFs with similar spatial structures, and the modulation of the end microstructures was achieved using the difference in F content. The output performance of friction power generation increases with the increase in F content, and the obtained polyacidic ligand materials can be used to construct self-powered corrosion protection systems, which can effectively protect metallic materials from corrosion.
RESUMO
A palladium-catalyzed asymmetric [3+2] cycloaddition reaction of vinylaziridines with α,ß-unsaturated ketones, wherein the alkenes have a single activator, is realized in high diastereo- and enantioselectivity, thus affording 3,4-disubstituted pyrrolidines in high yields with excellent eeâ values. The introduction of a methyl group at C1 of the vinyl group the vinylaziridines greatly improves the stereochemistry of the reaction. A plausible transition state is proposed.
Assuntos
Aziridinas/química , Cetonas/química , Paládio/química , Alcenos/química , Catálise , Reação de Cicloadição , EstereoisomerismoRESUMO
A highly regioselective palladium-catalyzed allylic alkylation of dienyl esters with nitromethane has been developed, providing selective access to the C-5 attacked products. The structures of the ligands as well as the steric effect of the substrates are important factors in determining the regiochemical outcome of the reaction.
RESUMO
Desymmetrization of carbon nucleophiles by palladium-catalyzed asymmetric allylic alkylation has been realized for the first time. Products with three chiral centers were obtained in good yield and with high diastereo- and enantioselectivity. The method offers an efficient access to optically active tropane derivatives.