One-pot synthesis of fluorinated 2-amino-pyrimidine-N-oxides. Competing pathways in the four-atom side-chain rearrangements of 1,2,4-oxadiazoles
作者:Silvestre Buscemi、Andrea Pace、Antonio Palumbo Piccionello、Nicolò Vivona、Marcella Pani
DOI:10.1016/j.tet.2005.10.071
日期:2006.2
2-(hydroxyamino)-pyrimidine from the reaction mixture evidenced the presence of a competing pathway where the N(4) nitrogen of the oxadiazole is involved in the formation of a regioisomeric pyrimidinium salt. The effect of the trifluoromethylgroup on the product distribution is discussed. By X-ray analysis, the crystal structure of two different N-oxide regioisomers has been unambiguously ascertained