Synthesis and Characterisation of Chromium (III) Compounds with Tetradentate N4 Macrocyclic Ligands

Abstract

Tetraamidemacrocyclic Ligands (N₄L¹ to N₄L⁴⁴) have been prepared by the condensation of various primary diamines i.e.- 1, 2- diaminoethane (NH­_2­CH₂CH₂NH₂), 1, 3-diaminopropane (NH₂CH­₂CH₂CH₂NH₂), 2-methyl-1,3-diaminopropane(NH₂CH₂CH(CH)₃CH₂NH₂),2,2-dimethyl1,3-diaminopropane (NH₂CH₂C(CH₃)₂CH₂NH₂), diethylenetriamine (NH₂(CH₂)₂NH(CH₂)₂NH₂)1,6 diaminohexanei.e.NH₂(CH₂)₆NH­₂,1,7-diaminoheptaneNH₂(CH₂)₇NH₂,1,8-diaminooctane. H₂(CH₂)₈NH₂, 1,9-diaminononane NH₂(CH₂)₉NH₂, 1,10-diaminodecane NH₂(CH₂)₁₀NH₂ and 1, 12-diaminododecane NH₂(CH₂)₁₂NH₂with various dicarboxylic acids i.e. malonic  (COOH)CH₂(COOH), succinic acid (COOH)CH₂CH₂(COOH), glutaric-(COOH)CH₂CH₂CH₂(COOH), and adipic (COOH)CH₂CH₂CH₂CH₂(COOH). in the presence of condensing reagents dicyclohexylcarbodiimide and 4- dimethyl aminopyridine, which on reduction give a new series of tetrazamacrocycles (MacL¹ to MacL⁴⁴) which forms complexes with CrCl₃.XH₂O These all complexes were characterized by various physicochemical techniques e.g. elemental analysis, molar conductance, UV- visible, IR, ¹H NMR, magnetic moment and XPS data and an octahedral geometry were established for these prepared [Cr(MacL)Cl₂]Cl complexes.