Letters in Organic Chemistry

Author(s): Fernanda A. Rosa, Helio G. Bonacorso, Nilo Zanatta, Alex F.C. Flores, Gabriela F. Fiss, Daniel J. Emmerich, Elisandra Scapin, Marcos A.P. Martins and Wilson Cunico

DOI: 10.2174/157017806776611962

Microwave-Assisted Regiospecific Synthesis of 2-Trifluoromethyl-7- Trihalomethylated Pyrazolo[1,5-a]Pyrimidines

Page: [358 - 362] Pages: 5

  • * (Excluding Mailing and Handling)

Abstract

The reaction of 5-trifluoromethyl-3-aminopyrazole with 1,1,1-trihalo-4-alkoxy-3-alken-2-ones CX3C (O)C(R2) = C(R1)OR, [where R2 = H, Me; R1 = H, alkyl, aryl, OEt and R = alkyl] both in the presence of environmentally benign microwave induced techniques and by the conventional method furnished eleven regiospecific halomethylated pyrazolo[1,5-a]pyrimidines. 1H- and 13C-NMR spectroscopy established that the 7-hydroxy-5-ethoxy-pyrazolo[1,5-a]-6,7-dihydropyrimidine intermediate was also formed.

Keywords: green chemistry, microwave irradiation, enones, pyrazoles, Pyrimidines