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
Here the aromatic formylation mediated by TiCl4 and dichloromethyl methyl ether previously described by our group has been explored for a wide range of aromatic rings, including phenols, methoxy- and methylbenzenes, as an excellent way to produce aromatic aldehydes. Here we determine that the regioselectivity of this process is highly promoted by the coordination between the atoms present in the aromatic moiety and those in the metal core.
Assuntos
Éter Bisclorometílico/química , Hidrocarbonetos Policíclicos Aromáticos/química , Titânio/química , Modelos Químicos , Modelos Moleculares , Estrutura MolecularRESUMO
A silver trifluoromethanesulfonate (AgOTf)-promoted direct and mild formylation of benzenes has been developed. The reaction utilizing dichloromethyl methyl ether (Cl2CHOMe) and AgOTf powerfully formylated various substituted benzenes under temperature conditions as low as -78 °C without losing the protecting groups on the phenolic hydroxyl group.
Assuntos
Derivados de Benzeno/síntese química , Éter Bisclorometílico/análogos & derivados , Éter Bisclorometílico/química , Mesilatos/química , Derivados de Benzeno/química , Estrutura MolecularAssuntos
Éter Bisclorometílico/toxicidade , Éteres Metílicos/toxicidade , Alquilantes/síntese química , Alquilantes/química , Alquilantes/farmacologia , Alquilantes/toxicidade , Animais , Éter Bisclorometílico/síntese química , Éter Bisclorometílico/química , Éter Bisclorometílico/farmacologia , Testes de Carcinogenicidade , Carcinógenos/síntese química , Carcinógenos/química , Carcinógenos/farmacologia , Carcinógenos/toxicidade , Cricetinae , Feminino , Guias como Assunto , Humanos , Masculino , Éteres Metílicos/química , Éteres Metílicos/classificação , Éteres Metílicos/farmacologia , Camundongos , Modelos Biológicos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/legislação & jurisprudência , RatosRESUMO
Experimental details are presented for the introduction and application of pi-allyloxymethyl protection for histidine side-chains.