SYNTHESIS OF AN ASYMMETRICAL TRIPODAL TETRAAMINE LIGAND AND ITS 5-COORDINATE COPPER(II) COMPLEX

A simple synthesis has been devised for the tripodal 3,3,4-tetraamine ligand N{(CH2)(3)NH2}(2){(CH2)(4)NH2} (L). This ligand forms a copper( II) complex, [Cu (LH)Cl-2]ClO4 (7), the structure of which has been de termined by X-ray diffraction. The cation contains a five-coordinate c opper atom, bonded to two chloride ions, the two propylamine groups an d the tertiary nitrogen atom of the ligand; the arrangement is a disto rted trigonal bipyramid, in which the two primary amine groups occupy the axial positions. The butylamine group of the ligand does not coord inate to copper but is protonated. It is involved in hydrogen bonding to the perchlorate ion. The e.p.r. spectrum of [Cu(dpt)Cl-2] is very s imilar to that of (7), suggesting that it also has a trigonal bipyrami dal structure.