RESUMO
A combination of dimethylzinc, perfluoroalkyl iodide, and LiCl afforded a new type of perfluoroalkyl (RF ) zinc ate complex. These complexes show much greater thermal stability than conventional perfluorinated metal species, such as RF -lithium species and Grignard reagents, and they can be used at room temperature or higher. The results of DFT calculations on the origin of the enhanced stability are reported and the synthetic utility of RF -zincate complexes is demonstrated.
Assuntos
Complexos de Coordenação/química , Fluorocarbonos/química , Compostos Organometálicos/química , Zinco/química , Complexos de Coordenação/síntese química , Fluorocarbonos/síntese química , Iodetos/síntese química , Iodetos/química , Compostos Organometálicos/síntese químicaRESUMO
A highly chemoselective perfluoroalkylation reaction of aromatic halides is reported. Thermally stable perfluoroalkylzinc reagents, generated by a rapid halogen-zinc exchange reaction between diorganozinc and perfluoroalkyl halide species, couple with a wide range of aryl halides in the presence of a copper catalyst, in moderate to high yields. Good stability of the perfluoroalkylzinc species was indicated by DFT calculation and the reagents were storable for at least three months under argon without loss of activity. This method is applicable to gram-scale synthesis, and its functional group tolerance compares favorably with reported protocols.