Tesis
Síntese de 1,1,1-trifluoro-4-metoxi-3-alquen-2-onas funcionalizadas e 1,2-azóis derivados
Fecha
2014-03-03Registro en:
KUHN, Bruna Pereira. Synthesis of 1,1,1-trifluoro-4-methoxy-3-alquen-2-ones
functionalized and 1,2-azole derivatives. 2014. 180 f. Dissertação (Mestrado em Química) - Universidade Federal de Santa Maria, Santa Maria, 2014.
Autor
Kuhn, Bruna Pereira
Institución
Resumen
This work describes the application of the method of trifluoroacetic anhydride acetal
acylation to four new functionalized ketones: 6-methyl-5-hepten-2-one, 4-phenyl-4-
oxobutanoic acid (3-benzoylpropionic acid), 5-bromo-2-acetylthiophene and 2-
propionylthiophene. The acylated products were obtained as β-trifluoromethyl ketones
alkoxyvinyl and β-diketones. The product derived from 2-propionylthiophene was
obtained as dihydrate, 3,3-dihydroxy-4,4,4-trifluoro-1-(2-thienyl)-2-butanone, its structure
was confirmed by X-ray diffraction crystallography. The acylated dielectrophilic
precursors were cyclized with dinucleophiles hydroxylamine, hydrazine, semicarbazide
and thiosemicarbazide to form the corresponding 5-trifluoromethyl-4,5-dihydroisoxazoles,
5-trifluoromethyl-4,5-dihydro-1H-pyrazoles and trifluoromethyl-1H-pyrazole
in good yields (>80%). The molecular structure of the synthesized products were
assigned based on the data of 1H NMR, 13C and X-ray diffraction.