Abstract: A novel chiral Salen 1 and its dinuclear Salen Mn complex 2 (host) were synthesized and characterized by elemental analysis,1H NMR,FT-IR,UV-Vis, and CD spectra. The molecular recognition of 2 with imidazoles and pydines were studied by method of UV-Vis spectrophotometric titration, and it seems that the binding constants are in the orders of K(Im) > K(2-MeIm) > K(N-MeIm) (imidazoles), K(4-MePy) > K(3-MePy) > K(Py) (pydines). All of them have a coordination number of two. The thermodynamic functions ΔrHmθ,ΔrSmθ were also calculated. The results indicated that the processes were exothermic and entropy decreasing. CD spectra of recognition process were studied and the results were consistent with those of thermodynamics. Moreover, the lowest energy configurations of host-guest were obtained by simulated annealing, and quantum chemical calculation was performed based on these configurations. The experimental phenomena were confirmed by the results of quantum chemical calculation.

Key words: Dinuclear chiral Salen Mn complex, Molecular recognition, CD spectra, 　Quantum chemical calculation