Synthesis And Properties Of The New Aza-crown Ether Compounds And Complexes

Aza-crown ethers are well known to have strong coordination ability for alkali and alkaline earth ions and to have excellent coordination ability for transition metal ions or ammonium ions. Therefore, aza-crown ethers have received much attention as receptors. For further investigation in this field, in this paper, we synthesized a series of new aza-crown ether compounds and their transition mental ion complexes. All of the aza-crown ethers and their complexes were characterized by EA, IR, UV, 1H NMR, 13C NMR. The antibacterial activities of the aza-crown ethers and complexes were also studied.1. Six kinds of new aza-crown ethers were prepared by using the p-chloronitrobenzene, diethanolamine, salicylaldehyde, diamine as materials. The syntheses of the new kinds of aza-crown ethers (L1-L6) are shown as follows.N-(p-Nitrophenyl)diethanolamine ( I ) was obtained by the reaction of 4-chloronitrobenzene with diethanolamine at 130C(oil bath). The reaction of ( I ) with p-toluenesulfonyl chloride gave N-(p-nitrophenyl)diethanoIamine di(p-toluenesulfonate) (II). Dialdehyde (III) was perepared by the reaction of (II) with salicylaldehyde in the presence of anhydrous K2CO3 in N,N-dimethylformide. In the syntheses of L1-L6, the dialdehyde (III) was condensed with different diamines in the mixture solution of methanol and trichloromethane. The corresponding Schiff base derivatives were not isolated, but instead of reduction which was carried out by slow addition of sodium borohydride to the reaction mixture. It is not necessary to carry out the ring closure step either under high dilution conditions or in the presence of template ions.Furthermore, A new Schiff base type macrocycle compound (L7) was prepared by the reaction of dialdehyde (III) with 1,3-phenylenediamine. In the synthesis of L4, a Schiff base derivative (L8) was also isolated.The structures proposed for the new macrocycles are consistent with the data obtained from their EA, IR, UV, 1H NMR, 13C NMR.2. Twenty eight complexes of the aza-crown ethers (L1-L6) with transition metal chlorides (CdCl2, MnCl2, CoCl2, NiCl2, CuCl2, ZnCl2) were prepared and characterized by EA, IR, UV and molar conductivity. The compositions of the complexes can be defined as MLCl2 nH2O (M = Cd, Mn, Co, Ni, Cu, Zn, L = L1- L6, n = 0-4).By contrasting the 1R spectra of aza-crown ethers and complexes, it was found that the vibration absorption of C-O-C and C-N had obvious shifts. The UV spectra of the ligands and metal complexes shown that the maximal absorption wavelengths also had obvious shirts. These results denote that the oxygen and nitrogen atoms in the aza-crown ethers coordinate with the transition metal ions. The molar conductance values indicate that the complexes of aza-crown ethers with transition metal chlorides are non-eletrolytes. These results show that both of the two chloride anions coordinated to the metal ions.3. The antibacterial activities of the aza-crown ethers and complexes were determined. The study results show that all compounds have antibacterial activities, and some compounds have excellent antibacterial activities. These results will provide some useful information for the syntheses of powerful bactericides.