Spectral Studies on Metal Complexes of a Newly Synthesized Azetidinone

Abstract

A dioxane solution of N-(4-amino-5-methyl-3-thiohydroxy-1,2,4- triazole)-3¢-carboxy-2¢-hydroxybenzalideneimine, LH₃ (I) on reacting with chloroacetyl chloride, in the presence of triethylamine, undergoes cyclization to form N-(4-amino-5-methyl-3-thiohydroxy-1,2,4-triazole)- 4-(3'-carboxy-2'-hydroxyphenyl)azetidin-2-one, L'H₃ (II). A methanolic solution of L'H₃ reacts with Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Fe(III), Zr(IV), MoO₂(VI) and UO₂(VI) ions to form the complexes, [M(L'H)·MeOH]₂ [where M = Mn(II), Co(II) or Ni(II)]; [Cu(L'H)]₂; [M(L'H)] [where M = Zn(II), Cd(II), MoO₂(VI) or UO₂(VI)]; [Fe(L'H)Cl]₂ and [Zr(OH)₂(L'H)]₂. The compounds have been characterized on the basis of elemental analyses, molar conductance, molecular weight, spectral (IR, UV-visible) studies and magnetic susceptibility measurements. L'H₃ behaves as a dibasic tridentate OON donor ligand in [Cu(L'H)]₂, while it acts as a dibasic tetradentate OONS donor ligand in rest of the compounds. The complexes, [M(L'H)·MeOH]₂ [M = Mn(II), Co(II) or Ni(II)]; [Cu(L'H)]₂; [Fe(L'H)Cl]₂ and [Zr(OH)₂(L'H)]₂ are dimers, while others are monomers. The dimeric complex, [Cu(L'H)]₂ exhibits subnormal magnetic moment and is involved in antiferromagnetic exchange, while all other complexes are magnetically dilute. The octahedral structure for Mn(II), Co(II), Ni(II), Fe(III), MoO₂(VI) and UO₂(VI) complexes, square planar structure for Cu(II) complex, tetrahedral structure for Zn(II) and Cd(II) complexes and pentagonal bipyramidal structure for Zr(IV) complex have been suggested.