Abstract: The ligand-exchange equilibria that are establishcd in Al(Ttfac)₃-acac and Al(Ttfac)₃ systems,where Ttfac=Theonyltrifluoroaeetone,acac=aeetylaeetonate,have been studied by means of ¹⁹F NMR spcctroscopy. For Al(Ttfac)₃-acac system,it is found that the distribution of complexes in mixtures accords with the statistical be-havior, For Al(Ttfac)₃-Al(acac)₃ systcm, the ligand-exchange equlibria may be des-cribed in terms of three indcpendent cqulibria.Equlilbrium constants have been deter-mined in chloroform solution, The relationship between the structure of complexes and energy is discussed in this paper.

Key words: Al (III) comlpexes of Ttfac and acac, ¹⁹F NMR, Ligand-dxchange reaction