Regiospecific Allylic Mono- and Dibromination of 4-Methoxy-1,1,1-trihalo-3-alken-2-ones and 5-Methoxy-1,1,1,2,2-pentafluoro-4-hexen-2-one, and their Applications to the Synthesis of Heterocycles - Martins, Marcos A P; Sinhorin, Adilson P; da Rosa, Adriano; Flores, Alex F C; Wastowski, Arci D; Pereira, Claudio M P; Flores, Darlene C; Beck, Paulo; Freitag, Rogerio A; Brondani, Sergio; Cunico, Wilson; Bonacorso, Helio G; Zanatta, Nilo (Synthesis, 2002)