1-ethoxycarbanyl-3-ferrocenyl-propane-1,3-dion and ferrocene-1,1 '-bis(2,4-dioxobutanoic acid ethylester) as ligands for transition metal ions. Crystal structure of bis(1-ethoxycarbonyl-3-ferrocenyl-propane-1,3-dionato)copper(II)

The ligands 1-ethoxycarbonyl-3-ferrocenyl-propane-1,3-dion and ferrocene-1, 1'-bis(2,4-dioxo-butanoic acid ethylester) have been prepared by reaction o f acetylferrocene or 1,1'-diacetylferrocene and diethyl oxalate. They yield neutral chelates with Cu-II, Ni-II, Zn-II, Co-II, and Mn-II. The acid diss ociation constants of the ligands and the stability constants of their meta l complexes including Fe-II complexes are reported. The structure of bis(1- ethoxycarbonyl-3-ferrocenyl-propane-1,3-dionato)copper(II) was determined b y Xray structure analysis. A cis arrangement with a nearly square planar co ordination sphere at the Cu atom is found.