Tetrahedron Letters, Vol. 34, No. 48. PP. 7731-174Q. 1993 P&cd in Great Britain ... Synthesis of Some Fluorinated Nitrogen Heterocycles from (Diethylaminomethylene)Hexafluoroacetylacetone ... Mustapha Soufyane, Catherine Mirand and Jean Levy* ... Laboratoire de Transformations