Synthesis of 3-trifluoroacetamidobenzoyltrifluoroacetone and its luminescent europium complexes

Abstract

Reaction of 3-aminoacetophenone with excess of methyl trifluoroacetate proceeds in two stages and leads to the formation of 3-trifluoroacetamidobenzoyltrifluoroacetone 3-CF3C(O)NHC6H4C(O)CH2C(O)CF3 instead of the expected 3-aminobenzoyltrifluoroacetone 3-NH2C6H4C(O)CH2C(O)CF3. The cause is the readily proceeding reaction of CF3COOCH3 with amine group of the source 3-aminoacetophenone and the initial formation of 3-trifluoroacetamidoacetophenone. On the basis of the synthesized β-diketone the luminescent complexes were synthesized: europium(III) tris(3-trifluoroacetamidobenzoyltrifluoroacetonate) trihydrate and europium(III) tris(3-trifluoroacetamidobenzoyltrifluoroacetonate)(phenanthroline). The trifluoroacetylamide group is converted into the primary amine by treatment the solutions of the europium complexes with aqueous alkali. The molecular and crystal structures of 3-trifluoroacetamidoacetophenone were investigated.