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
The title compound [Zn(Him2Py)(N3)2]2 (Zn2C26H38N18O2, Mr = 765.48) has been prepared and structurally characterized by X-ray diffraction methods. It crystallizes in monoclinic, space group P21/n with a = 10.989(3), b...The title compound [Zn(Him2Py)(N3)2]2 (Zn2C26H38N18O2, Mr = 765.48) has been prepared and structurally characterized by X-ray diffraction methods. It crystallizes in monoclinic, space group P21/n with a = 10.989(3), b = 11.519(3), c = 13.812(4) ? b = 101.700(5), V = 1711.9(9) ?, Z = 2, Dc = 1.485 g/cm3, m(MoKa) = 1.456 mm~1, F(000) = 792, the final R = 0.0401 and wR = 0.0861 for 2054 observed reflections with I>2s(I). The imino nitroxide 2-(3- methyl-2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl (im2Py) was reduced to obtain 2-(3-methyl -2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-ydroxy (Him2Py) coordinating to the zinc (II) ion, around which the coordination geometry is a square-based pyramid with a terminal nitrogen atom located at the apical position. The four basal sites are occupied by two m1,1 nitrogen atoms from two different bridging azide ions and two nitrogen atoms from Him2Py. The units of [Zn(Him2Py)(N3)2]2 were connected as two dimension planes by intermolecular hydrogen bonds.展开更多
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.
基金This work was supported by the National Natural Science Foundation of China (No. 20171025 and No. 90101028)
文摘The title compound [Zn(Him2Py)(N3)2]2 (Zn2C26H38N18O2, Mr = 765.48) has been prepared and structurally characterized by X-ray diffraction methods. It crystallizes in monoclinic, space group P21/n with a = 10.989(3), b = 11.519(3), c = 13.812(4) ? b = 101.700(5), V = 1711.9(9) ?, Z = 2, Dc = 1.485 g/cm3, m(MoKa) = 1.456 mm~1, F(000) = 792, the final R = 0.0401 and wR = 0.0861 for 2054 observed reflections with I>2s(I). The imino nitroxide 2-(3- methyl-2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl (im2Py) was reduced to obtain 2-(3-methyl -2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-ydroxy (Him2Py) coordinating to the zinc (II) ion, around which the coordination geometry is a square-based pyramid with a terminal nitrogen atom located at the apical position. The four basal sites are occupied by two m1,1 nitrogen atoms from two different bridging azide ions and two nitrogen atoms from Him2Py. The units of [Zn(Him2Py)(N3)2]2 were connected as two dimension planes by intermolecular hydrogen bonds.