Six novel chiral dinuclear Salen complexes[Cu 2 L 1 ·H 2 O(3a),Cu 2 L 2 (3b),Ni 2 L 1 ·2H 2 O(4a),Ni 2 L 2 (4b),Mn 2 Cl 2 L 1 ·H 2 O(5a),Mn 2 Cl 2 L 2 (5b)]have been synthesized(L 1 and L 2 are chiral d...Six novel chiral dinuclear Salen complexes[Cu 2 L 1 ·H 2 O(3a),Cu 2 L 2 (3b),Ni 2 L 1 ·2H 2 O(4a),Ni 2 L 2 (4b),Mn 2 Cl 2 L 1 ·H 2 O(5a),Mn 2 Cl 2 L 2 (5b)]have been synthesized(L 1 and L 2 are chiral dimeric Salen ligands with different chain length which were synthesized from(R,R) - diaminocyclohexane,salicylaldehyde,4,4 ’- (1,10 - decaneoxy)sali - cylaldehyde,4,4 ’- (1,6 - hexyloxy)salicylaldehyde).These compounds were charactered by elemental analysis,1 H NMR,FT - IR,UV - Vis and CD spectra.The FT - IR,UV - Vis and CD spectra were discussed and compared with those of monomeric ligand and complex in detail.It was found that the spectra properties of compounds of differ - ent chain length were almost alike,and the properties of dimeric and monomeric compound were similar too.Furthermore Cotton effect and Cotton split of CD spectra of these chiral compounds were explained by the exciton interaction theory.It seemed that the direction of Cotton split depend on the configuration of diaminohexane.(R,R) - diaminohexane determine the chirality of Salen compounds as negative,and the positive and negative compo - nent of Cotton split lie at higher and lower energy respectively.展开更多
The macrocyclic ligand(L) and its dinuclear copper(Ⅱ) and zinc(Ⅱ) complexes have been synthesized. The crystal structure of [Cu 2L(Him) 2](ClO 4) 4·2H 2O has been determined by single crystal X ray diffraction....The macrocyclic ligand(L) and its dinuclear copper(Ⅱ) and zinc(Ⅱ) complexes have been synthesized. The crystal structure of [Cu 2L(Him) 2](ClO 4) 4·2H 2O has been determined by single crystal X ray diffraction. It crystallizes in a monoclinic system, the space group P2 1/c , a =0.951 2(2) nm, b =2.010 4(4) nm, c =1.202 5(2) nm, β =98.89(3)°, V =2.271 9(8) nm 3, Z=2, D c=1.599 Mg/m 3 , F (000) = 876 , R =0.059 1, wR =0.173 3, GOF(F)=1.009. The copper(Ⅱ) atom is five coordinated with four nitrogen atoms of the macrocyclic ligand and one nitrogen atom of imidazole. The stepwise stability constants of the 1∶1 and 2∶1 molar ratios of Cu to L and Zn to L complexes were determined by potentiometric titration in KCl supporting electrolyte(0.100 mol/L) at 25 ℃. The results indicated that zinc(Ⅱ) ion can form hydroxide bridged dinuclear complex [Zn 2(OH)L] 3+ , while the copper(Ⅱ) ion can only form dinuclear complex 3+ with macrocyclic ligand.展开更多
文摘Six novel chiral dinuclear Salen complexes[Cu 2 L 1 ·H 2 O(3a),Cu 2 L 2 (3b),Ni 2 L 1 ·2H 2 O(4a),Ni 2 L 2 (4b),Mn 2 Cl 2 L 1 ·H 2 O(5a),Mn 2 Cl 2 L 2 (5b)]have been synthesized(L 1 and L 2 are chiral dimeric Salen ligands with different chain length which were synthesized from(R,R) - diaminocyclohexane,salicylaldehyde,4,4 ’- (1,10 - decaneoxy)sali - cylaldehyde,4,4 ’- (1,6 - hexyloxy)salicylaldehyde).These compounds were charactered by elemental analysis,1 H NMR,FT - IR,UV - Vis and CD spectra.The FT - IR,UV - Vis and CD spectra were discussed and compared with those of monomeric ligand and complex in detail.It was found that the spectra properties of compounds of differ - ent chain length were almost alike,and the properties of dimeric and monomeric compound were similar too.Furthermore Cotton effect and Cotton split of CD spectra of these chiral compounds were explained by the exciton interaction theory.It seemed that the direction of Cotton split depend on the configuration of diaminohexane.(R,R) - diaminohexane determine the chirality of Salen compounds as negative,and the positive and negative compo - nent of Cotton split lie at higher and lower energy respectively.
文摘The macrocyclic ligand(L) and its dinuclear copper(Ⅱ) and zinc(Ⅱ) complexes have been synthesized. The crystal structure of [Cu 2L(Him) 2](ClO 4) 4·2H 2O has been determined by single crystal X ray diffraction. It crystallizes in a monoclinic system, the space group P2 1/c , a =0.951 2(2) nm, b =2.010 4(4) nm, c =1.202 5(2) nm, β =98.89(3)°, V =2.271 9(8) nm 3, Z=2, D c=1.599 Mg/m 3 , F (000) = 876 , R =0.059 1, wR =0.173 3, GOF(F)=1.009. The copper(Ⅱ) atom is five coordinated with four nitrogen atoms of the macrocyclic ligand and one nitrogen atom of imidazole. The stepwise stability constants of the 1∶1 and 2∶1 molar ratios of Cu to L and Zn to L complexes were determined by potentiometric titration in KCl supporting electrolyte(0.100 mol/L) at 25 ℃. The results indicated that zinc(Ⅱ) ion can form hydroxide bridged dinuclear complex [Zn 2(OH)L] 3+ , while the copper(Ⅱ) ion can only form dinuclear complex 3+ with macrocyclic ligand.