Studies On Metal Complexes Based On Aminobenzoic Acids And Their Schiff Bases

In recent years, a considerable interest has been focused on the novel coordination compounds because of their fascinating structural and topological features, and their potential application in functional materials and molecular recognition. Aminobenzoic acids and their Schiff bases are the polydentate organic ligands containing N,O atoms, which can coordinate to several metallic ions and may exhibit various coordination modes, so they are the good ligands to design and synthesize novel complexes. In this paper, we reviewed the previous work based on aminobenzoic acids and their Schiff bases in details. We synthesized 15 unreported coordination compounds by using 3,5-diaminobenzoic acid (3,5-diabaH),4-N(2'-pyridylimine) benzoic acid (HL1),3-N(2'-pyridylimine) benzoic acid (HL2) as ligands. The compounds have been characterized by IR,elemental analysis and single crystal X-ray diffraction,the magnetic properties of some complexes have been studied as well. The main works is as follows:1. Three-dimensional cadmium and manganese polymers [Cd(3,5-diaba)(μ1,1-N3)]n (1),[Mn(3,5-diaba)(μ1,3-N3)]n (2) have been prepared by using 3,5-diaminobenzoic acid (3,5-diabaH) as ligand and N3ˉas counter-anion. The compounds have been characterized by IR,elemental analysis. The single crystal X-ray diffraction shows that complex (1) crystallized in monoclinic, space group P21/c with a = 8.3972(13),b = 16.135(2),c = 7.0043(11) A;β= 112.921(2) A. Complex (2) crystallized in orthorhombic, space group Pbca with a = 12.6897(9),b = 8.6978(6),c = 15.9901(11) A. Deprotonated 3,5-diabaH acted both as aμ4- bridging ligand linking four metal ions in two complexes, and the N3ˉexhibitedμ-1,1 andμ-1,3 coordination mode in (1) and (2), respectively.2. Two mononuclear complexes [Cu(HL1)2]·(ClO4)2 (3),[Cu(HL1)2SO4]·3H2O (6), one two-dimensional complex [Cu2(L1)2Cl2]n·3H2O (4), one tetranuclear complex [Cu4(L1)2(HL1)2Cl4]·(CH3OH)2·(ClO4)2 (5) have been synthesized by the reaction between 4-N(2'-pyridylimine) benzoic acid (HL1) and different copper salts. The compounds have been characterized by IR,elemental analysis. The single crystal X-ray diffraction shows that complex (3) crystallized in monoclinic, space group C2/c with a = 15.781(2),b = 11.4203(16),c = 16.159(2) A;β=106.303(2)A. Complex (4) crystallized in monoclinic, space group C2/c with a = 17.063(2),b = 7.9450(9),c = 21.097(2) A;β= 95.062(7) A. Complex...