RESUMO
Formylations of fluorine-containing aromatic compounds with dichloromethyl alkyl ethers have been investigated. Dichloromethyl propyl ether and dichloromethyl butyl ether have been applied for the formylation of fluorine-containing anisoles to give the corresponding aldehydes in good yields. Application of these ethers is preferable to that of methyl ether, which is prepared from volatile methyl formate. Reaction of fluorine-containing phenols with these dichloromethyl alkyl ethers did not give salicylaldehyde derivatives, leading instead to corresponding aryl formates in high yields. A plausible mechanism is discussed.
Assuntos
Éter Bisclorometílico/química , Flúor/química , Aldeídos/química , Derivados de Benzeno/química , Éteres/química , Ácidos de Lewis/químicaRESUMO
A topological surface state that is protected physically under the Bi2Te3-like five-layer block has been revealed on the Pb-based topological insulator (TI) PbBi4Te7 by bulk sensitive angle-resolved photoelectron spectroscopy (ARPES). Furthermore, conservation of the spin polarization of the hidden topological surface states is directly confirmed by bulk-sensitive spin ARPES observation. This finding paves the way to realize the real spintronics devices by TIs that are operable in the real environment.