Structures of the yttrium complexes of 1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid (H4dota) and N,N″-bis(benzylcarbamoylmethyl)diethylenetriamine-N,N′,N″-triacetic acid and the solution structure of a zirconium complex of H4dota
Abstract
The solid-state crystal structure of Na[Y(dota)(H2O)]·4H2O (H4dota = 1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid) at 115 K has been obtained together with the solution structure of the neutral zirconium complex. The yttrium complex shows a mono-capped (H2O) square-antiprismatic structure while the solution 1H NMR spectra of [Zr(dota)(H2O)] suggest that a structure of lower symmetry is adopted and a minor isomer is observed. The crystal structure of the yttrium complex of N,N″-bis(benzylcarbamoylmethyl)diethylenetriamine-N,N′,N″-triacetic acid has revealed amide carbonyl ligation in a distorted mono-capped square-antiprismatic structure, with one metal-bound water molecule.